System and method for selecting and updating a set of probing devices

Abstract

Systems and methods for Wi-Fi sensing are provided. A Wi-Fi system includes a plurality of networked devices, the plurality of networked devices including a plurality of sensing-enabled devices and an access point. The Wi-Fi system is configured to identify a candidate set of the plurality of networked devices, establish a plurality of candidate sensing links between the plurality of candidate devices and the access point, monitor sensing transmissions transmitted over the plurality of candidate sensing links, identify a set of sensing links according to the sensing transmissions, and transmit the identified set of sensing links to the access point. A plurality of selected sensing links is established between a selected device of the plurality of candidate devices and the access point. The Wi-Fi system is further configured to update the sensing link in accordance with the detected sensing transmission. The Wi-Fi system may be configured to identify sensing links according to sensing probe information and / or a plurality of time domain channel representation information (TD-CRI) profile sets between candidate sensing links.

Description

Technical Field

[0001] The present disclosure generally relates to systems and methods for Wi-Fi sensing. Specifically, the present disclosure relates to systems and methods for selecting and updating a set of probe devices for Wi-Fi sensing. Background Art

[0002] Motion detection systems have been used to detect the movement of objects, such as in indoor or outdoor areas. In some example motion detection systems, infrared or optical sensors are used to detect the movement of objects in the sensor's field of view. Motion detection systems have been used in security systems, automatic control systems, and other types of systems. WLAN sensing systems (which may be referred to as Wi-Fi sensing systems) are a recent addition to motion detection systems. A Wi-Fi sensing system may be a network of Wi-Fi-enabled devices, which may be part of an IEEE 802.11 network. In one example, a Wi-Fi sensing system may be configured to detect features of interest in a sensing space. A sensing space may refer to any physical space in which a Wi-Fi sensing system may operate, such as a residential area, a workplace, a shopping mall, a gymnasium or stadium, a garden, or any other physical space. Features of interest may include motion and motion tracking of objects, presence detection, intrusion detection, gesture recognition, fall detection, respiratory rate detection, and other applications. Summary of the invention

[0003] The present disclosure generally relates to systems and methods for Wi-Fi sensing. In particular, the present disclosure relates to systems and methods for selecting a group of detection devices for Wi-Fi sensing.

[0004] Systems and methods for Wi-Fi sensing are provided. In an example embodiment, a method for Wi-Fi sensing performed by a Wi-Fi system is described, the Wi-Fi system including a plurality of networked devices. The plurality of networked devices include a plurality of sensing-capable devices and an access point. The method includes identifying a candidate set of the plurality of networked devices, the candidate set including a plurality of candidate devices capable of establishing a transmission link with an access point. The method further includes establishing a plurality of candidate sensing links between the plurality of candidate devices and the access point. In some embodiments, the method includes monitoring sensing transmissions sent through the plurality of candidate sensing links. The method further includes identifying a sensing link set based on the sensing transmissions, the sensing link set including a plurality of selected sensing links selected from the plurality of candidate sensing links. In some embodiments, the method includes establishing the plurality of selected sensing links between a selected device from the plurality of candidate devices and an access point.

[0005] In some embodiments, monitoring the sensed transmission includes determining an average power of the sensed transmission over an analysis period.

[0006] In some embodiments, monitoring the sensing transmission includes identifying a plurality of power variations, each power variation being characterized by a grouping of one or more candidate sensing links, the grouping of the one or more candidate sensing links showing a variation in received power compared to an average power of the sensing transmission of the corresponding candidate sensing link for one or more sampling instances during the analysis period.

[0007] In some embodiments, identifying the set of sensing links includes identifying the plurality of sensing links according to a sensing spatial coverage metric.

[0008] In some embodiments, identifying the multiple sensing links based on the sensing space coverage metric includes determining a power variation test set for analysis that includes a subset of power variations selected from the multiple power variations through the sensing space coverage metric; determining a power ratio parameter for test power variations in the power variation test set, comparing the power ratio parameter with a ratio threshold factor; and in response to the power ratio parameter exceeding the ratio threshold factor, selecting selected candidate sensing links from the groupings of the test power variations for inclusion in the sensing link set based on the candidate sensing links appearing in a maximum number of the groupings of the multiple power variations.

[0009] In some embodiments, identifying the multiple sensing links based on the sensing space coverage metric further includes determining additional power ratio parameters for additional power variations in the power variation test set; for each additional power variation in the additional power variations, comparing the additional power ratio parameter with the ratio threshold factor; and for each additional power variation having an additional power ratio parameter that exceeds the ratio threshold factor, selecting additional selected candidate sensing links from each grouping of the additional power variations to be included in the sensing link set based on the candidate sensing links that appear in a maximum number of the multiple power variations.

[0010] In some embodiments, determining the power change test set includes selecting a first power change from the multiple power changes based on the importance levels of the multiple power changes; and selecting a second power change from the remaining power changes in the multiple power changes that does not have a candidate sensing link in common with the first power change based on the importance levels of the remaining power changes in the multiple power changes, wherein the power change test set includes the first power change and the second power change.

[0011] In some embodiments, the power variation test set further comprises one or more additional power variations, such that each candidate sensing link appears in only one group from among the first power variation, the second power variation and the one or more additional power variations.

[0012] In some embodiments, the importance level is determined based on at least one of: a combination length, the combination length representing the number of candidate sensing links that appear in the multiple power changes; a change counter, the change counter representing the number of occurrences of each power change from the multiple power changes; and a maximum string length, the maximum string length representing the maximum number of consecutive occurrences of each power change from the multiple power changes.

[0013] In some embodiments, determining the power ratio parameter includes dividing a first maximum string length by a second maximum string length, wherein the first maximum string length represents a maximum consecutive number of occurrences of a test power change from the power change test set in the analysis period, and the second maximum string length represents a maximum consecutive number of occurrences of a single link power change associated with each candidate sensing link of the grouping of the test power changes in the analysis period.

[0014] In some embodiments, determining the power ratio parameter includes dividing a first change counter representing a number of occurrences of a test power change from the power change test set in the analysis period by a second change counter representing a maximum number of occurrences of a single link power change from each candidate sensing link associated with the group of the test power changes in the analysis period.

[0015] The present disclosure generally relates to systems and methods for Wi-Fi sensing. In particular, the present disclosure relates to systems and methods for updating a set of detection devices.

[0016] Systems and methods for Wi-Fi sensing are provided. In an example embodiment, a method for Wi-Fi sensing performed by a Wi-Fi system is described, the Wi-Fi system including a plurality of networked devices. The plurality of networked devices include a plurality of sensing-capable devices and an access point. The method includes maintaining a plurality of selected sensing links as a sensing link set between a selected device among the plurality of sensing-capable devices and the access point. In some embodiments, the method further includes identifying a plurality of candidate links as a candidate link set between an unselected device among the plurality of sensing-capable devices and the access point, and identifying a plurality of evaluation links from the candidate link set and the sensing link set as an evaluation link set. Additionally, in some embodiments, the method includes determining an allocation of channel resources for the plurality of evaluation links, establishing the plurality of evaluation links according to the allocation, and monitoring sensing transmissions on the plurality of evaluation links during an analysis period. In some embodiments, the method includes identifying an updated sensing link set according to the sensing transmission. The updated sensing link set includes a plurality of updated sensing links selected from the plurality of evaluation links according to a sensing space coverage metric. The method further includes establishing an updated sensing link set.

[0017] In some embodiments, identifying the plurality of candidate links includes performing a discovery process on sensing-capable devices, and including the discovered sensing-capable devices as candidate devices in a candidate link set representing candidate links.

[0018] In some embodiments, identifying the plurality of candidate links includes identifying a fine tuning link that is not included in the sensing link set, and including the fine tuning link as a candidate link in the candidate link set.

[0019] In some embodiments, determining the set of evaluation links includes selecting one or more sensing links of the plurality of sensing links as evaluation links, and selecting a subset of the plurality of candidate links as evaluation links.

[0020] In some embodiments, the method further includes determining that a congestion metric of the access point is above a congestion threshold, and selecting one or more active sensing-capable devices among the candidate devices in the candidate link set for inclusion in the evaluation link set.

[0021] In some embodiments, determining the allocation of the channel resources for the one or more active sensing-capable devices included in the evaluation link set includes maintaining an existing allocation of resource units (RUs) for the one or more active sensing-capable devices included in the evaluation link set.

[0022] In some embodiments, the method further includes determining that a congestion metric of the access point is below a congestion threshold, and selecting one or more idle sensing-capable devices among the candidate devices in the candidate link set for inclusion in the evaluation link set.

[0023] In some embodiments, determining the allocation of the channel resources for the one or more idle sensing-capable devices included in the evaluation link set includes allocating resource units (RUs) to the one or more idle sensing-capable devices included in the evaluation link set.

[0024] In some embodiments, the method further includes selecting one or more active sensing-capable devices among the candidate devices in the candidate link set to be included in the evaluation link set, wherein determining the allocation of the channel resources for the sensing-capable devices included in the evaluation link set includes maintaining an existing allocation of RUs for the selected devices, allocating RUs for the one or more idle sensing-capable devices, and maintaining an existing allocation of RUs for the one or more active sensing-capable devices.

[0025] In some embodiments, the method further comprises determining a reallocation of channel resources for the plurality of evaluation links based on changes in data link bandwidth on the plurality of evaluation links during an analysis period.

[0026] The present disclosure generally relates to systems and methods for Wi-Fi sensing. In particular, the present disclosure relates to systems and methods for adapting the selection of a set of probe devices according to network utilization.

[0027] Systems and methods for Wi-Fi sensing are provided. In an example embodiment, a method for Wi-Fi sensing performed by a Wi-Fi system is described, the Wi-Fi system including a plurality of networked devices. The plurality of networked devices include a plurality of sensing-capable devices and an access point. The method includes obtaining sensing probe information. The sensing probe information includes information about a plurality of power variations in a plurality of candidate sensing links between the plurality of sensing-capable devices and the access point, each power variation being characterized by a grouping of one or more candidate sensing links, the grouping of the one or more candidate sensing links showing a variation in received power compared to an average power of sensed transmissions of the corresponding candidate sensing link during one or more sampling instances of an analysis period. In some embodiments, the method further includes determining a plurality of data usage values ​​corresponding to the plurality of candidate sensing links. The method further includes identifying a sensing link set based on a sensing spatial coverage metric determined from the sensing probe information and the plurality of data usage values. The sensing link set includes a plurality of representative sensing links selected from the plurality of candidate sensing links. In some embodiments, the method includes establishing the plurality of representative sensing links between corresponding sensing-capable devices among the plurality of sensing-capable devices and the access point.

[0028] In some embodiments, obtaining the sensing probe information includes establishing a plurality of candidate sensing links between the plurality of sensing-capable devices and the access point, monitoring sensing transmissions sent via the plurality of candidate sensing links during the analysis period, and identifying the plurality of power changes based on the sensing transmissions.

[0029] In some embodiments, obtaining the sensing detection information includes accessing previously stored sensing information, and the multiple candidate sensing links include original sensing links in a previously established sensing link set and fine-tuning sensing links not included in the previously established sensing link set, and each power change has at least one original sensing link.

[0030] In some embodiments, identifying the set of sensing links includes identifying a congestion sensing link from the original sensing links as having a corresponding data usage value exceeding a congestion threshold from the multiple data usage values; identifying a power change corresponding to the congestion sensing link; identifying one or more fine-tuning sensing links belonging to the power change; and selecting the representative sensing link for the power change from the congestion sensing link and the one or more fine-tuning sensing links.

[0031] In some embodiments, identifying the set of sensing links further includes identifying additional congestion sensing links from the original sensing links based on the multiple data usage values; identifying additional power changes corresponding to the additional congestion sensing links; identifying an additional set of one or more fine-tuning sensing links belonging to the additional power changes; and for each additional power change, selecting a corresponding representative sensing link from the corresponding additional congestion sensing link and the corresponding additional set of one or more fine-tuning sensing links.

[0032] In some embodiments, selecting the representative sensing link further includes selecting the fine-tuning sensing link that appears in a plurality of groups characterizing a maximum number of the plurality of power variations as the representative sensing link.

[0033] In some embodiments, selecting the representative sensing link further includes selecting the fine-tuning sensing link having a lowest data usage value among the plurality of data usage values ​​as the representative sensing link.

[0034] In some embodiments, the representative sensing link for the power variation is selected from the congestion sensing link and the one or more fine tuning sensing links according to a switching factor defined for each of the congestion sensing link and the one or more fine tuning sensing links.

[0035] In some embodiments, the switching factor is defined as the number of occurrences of a link in the plurality of power-varied packets divided by a data usage value corresponding to the link.

[0036] In some embodiments, the power variation includes the congestion sensing link and the non-congestion fine-tuning sensing link, and the representative sensing link is selected from among the congestion sensing link and the non-congestion fine-tuning sensing link according to a highest switching factor.

[0037] In some embodiments, the power variation includes the congestion sensing link and a plurality of non-congestion fine-tuning sensing links, and the representative sensing link is selected from the congestion sensing link and the plurality of non-congestion fine-tuning sensing links according to a highest switching factor.

[0038] In some embodiments, the representative sensing link is further selected from two non-congested fine-tuning sensing links having the same switching factor according to the non-congested fine-tuning sensing link having a lower link number.

[0039] In some embodiments, the representative sensing link for the power variation is selected to balance link loads in the set of sensing links.

[0040] The present disclosure generally relates to systems and methods for Wi-Fi sensing. Specifically, the present disclosure relates to systems and methods for selecting sensing devices using physical parameters of a link.

[0041] Systems and methods for Wi-Fi sensing are provided. In an example embodiment, a method for Wi-Fi sensing performed by a Wi-Fi system is described, the Wi-Fi system including a plurality of networked devices. The plurality of networked devices include a plurality of sensing-capable devices and an access point. The method includes identifying a candidate set of the plurality of networked devices. The candidate set includes a plurality of candidate devices capable of establishing a transmission link with the access point. In some embodiments, the method further includes establishing a plurality of candidate sensing links between the plurality of candidate devices and the access point, and obtaining a plurality of time domain channel representation information (TD-CRI) profile sets corresponding to corresponding candidate sensing links in the plurality of candidate sensing links. In addition, in some embodiments, the method includes identifying a plurality of TD-CRI spans corresponding to corresponding candidate sensing links in the plurality of candidate sensing links according to the plurality of TD-CRI profile sets, and identifying a sensing link set according to the plurality of TD-CRI spans. The sensing link set includes a plurality of selected sensing links selected from the plurality of candidate sensing links. The method also includes establishing the plurality of selected sensing links between selected devices in the candidate devices and the access point.

[0042] In some embodiments, obtaining each TD-CRI profile in the plurality of TD-CRI profile sets for a candidate sensing link in the plurality of candidate sensing links includes obtaining, for each candidate sensing link, a plurality of TD-CRI measurement results at a plurality of sampling instances in a filter window; and applying an averaging filter to the plurality of TD-CRI measurement results to obtain each TD-CRI profile.

[0043] In some embodiments, the averaging filter includes at least one of a low pass filter and an exponential moving average filter.

[0044] In some embodiments, the method further comprises removing a time shift from one or more TD-CRI measurement results of the plurality of TD-CRI measurement results before applying the averaging filter.

[0045] In some embodiments, the multiple TD-CRI profile sets include a TD-CRI profile set for each of the multiple candidate sensing links obtained during the analysis period, wherein each TD-CRI profile set includes multiple TD-CRI profiles, and the multiple TD-CRI profiles each correspond to a filter window in the analysis period.

[0046] In some embodiments, each TD-CRI span of the multiple TD-CRI spans corresponds to a TD-CRI profile set in the multiple TD-CRI profile sets and is selected from a plurality of filter window TD-CRI spans, wherein the plurality of filter window TD-CRI spans correspond to the plurality of TD-CRI profiles in the TD-CRI profile set.

[0047] In some embodiments, selecting the plurality of TD-CRI spans comprises determining each TD-CRI span as a maximum filter window TD-CRI span TD-CRI for each TD-CRI profile set.

[0048] In some embodiments, selecting the plurality of TD-CRI spans comprises determining each TD-CRI span as an average of the plurality of filter window TD-CRI spans for each TD-CRI profile set.

[0049] In some embodiments, each filter window TD-CRI span of the plurality of filter window TD-CRI spans is obtained from a corresponding TD-CRI profile.

[0050] In some embodiments, obtaining the multiple filter window TD-CRI spans includes identifying valid time domain pulses in the corresponding TD-CRI profile as time domain pulses whose amplitude exceeds an amplitude threshold, identifying a first index of a first valid time domain pulse with a lowest time delay among the valid time domain pulses in the corresponding TD-CRI profile, identifying a last index of a last valid time domain pulse with a maximum time delay among the valid time domain pulses in the corresponding TD-CRI profile, and defining each filter window TD-CRI span as the last index of the corresponding TD-CRI profile minus the first index.

[0051] In some embodiments, for each TD-CRI profile, the amplitude threshold is determined as a percentage relative to a maximum amplitude of time domain pulses in the TD-CRI profile.

[0052] In some embodiments, identifying a sensing link set based on the multiple TD-CRI spans includes identifying multiple power variations, each power variation is characterized by a grouping of one or more candidate sensing links, the grouping of the one or more candidate sensing links showing a variation in received power compared to an average power of a sensed transmission of the corresponding candidate sensing link for one or more sampling instances during an analysis period; determining a power variation test set including a subset of power variations selected from the multiple power variations; and for each power variation in the power variation test set, selecting a selected candidate sensing link from the grouping of the test power variations based on the candidate sensing link having the largest TD-CRI span to be included in the sensing link set.

[0053] Other aspects and advantages of the present disclosure will become apparent from the following detailed description taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The foregoing and other objects, aspects, features and advantages of the present disclosure will become more apparent and can be better understood by referring to the following description taken in conjunction with the accompanying drawings, in which:

[0055] Figure 1 is a diagram illustrating an example wireless communication system;

[0056] Figure 2A and Figure 2B is a diagram illustrating example wireless signals transmitted between wireless communication devices;

[0057] Figure 3A and Figure 3B It shows that according to Figure 2A and Figure 2B a plot of an example of a channel response calculated for a wireless signal transmitted between wireless communication devices in;

[0058] Figure 4A and Figure 4B is a diagram illustrating example channel responses associated with motion of objects in different regions of space;

[0059] Figure 4C and Figure 4D It shows Figure 4A and Figure 4B a plot of an example channel response for , the example channel response superimposed on an example channel response associated with no motion in space;

[0060] Figure 5 Describes some architectural implementations of systems for Wi-Fi sensing according to some embodiments;

[0061] Figure 6 An example of a WLAN sensing procedure according to some embodiments is depicted;

[0062] Fig. 7A depicts an example of a sensing measurement setup request frame format according to some embodiments;

[0063] Figure 7B An example of a sensed measurement parameter element according to some embodiments is shown;

[0064] Figure 7C An example of the format of a sensory measurement parameter field according to some embodiments is shown;

[0065] Fig.7D depicts an example of a sensing measurement setup response frame according to some embodiments;

[0066] Fig. 8A Depicting one-to-many and many-to-many aspects of examples of WLAN sensing procedures according to some embodiments;

[0067] Figure 8B depicts paired aspects of an example of a WLAN sensing procedure according to some embodiments;

[0068] Fig. 9 depicts a message flow for a trigger-based (TB) sensing measurement instance of a WLAN sensing procedure consisting of an NDPA probe or a TF probe according to some embodiments;

[0069] Fig. 10A and Fig. 10B depicts an example of a trigger-based (TB) sensing measurement example according to some embodiments;

[0070] Fig.11A and Fig. 11B depicts an example of a single TB sensing measurement instance including a polling phase, a trigger frame detection phase, and an NDPA detection phase according to some embodiments;

[0071] Fig.12 Depicting a message flow for a non-TB sensing measurement example of a WLAN sensing procedure with both uplink sounding and downlink sounding according to some embodiments;

[0072] Fig.13 depicts an example of a single non-TB sensing measurement instance according to some embodiments;

[0073] Fig.14 Depicting an example of a common action frame format of a sensing measurement report frame and sensing measurement report field formats according to some embodiments;

[0074] FIG. 15A to FIG. 15Hdepicts a hierarchy of fields within a sense trigger according to some embodiments;

[0075] Fig.16 Presents a representation of using an active tone bitmap to communicate the location of a selected one or more time-domain pulses from a sensing receiver to a sensing algorithm in accordance with some embodiments;

[0076] Fig.17 Presents a representation of using a full bitmap to communicate the location of a selected one or more time-domain pulses from a sensing receiver to a sensing algorithm in accordance with some embodiments;

[0077] Fig.18 Presents a representation of communicating the position of the selected one or more time domain pulses from a sensing receiver to a sensing algorithm using the positioning of the selected one or more time domain pulses in a full time domain CRI (full TD-CRI) according to some embodiments;

[0078] Fig.19 A management frame carrying sensing measurement parameters for sensing transmission according to some embodiments is shown;

[0079] Fig. 20A shows an example of the format of a control frame according to some embodiments, and Fig. 20B The format of the Sensing Transmission Advertisement Control field of the Control Frame is shown;

[0080] Fig.21A Another example of the format of a control frame according to some embodiments is shown, and Fig. 21B shows the format of the Sensing Measurement Control field of the Control Frame;

[0081] Fig. 22 A management frame carrying a CRI transmission message according to some embodiments is shown;

[0082] Fig.23 depicts a diagram of a filtered time domain CRI (filtered TD-CRI) according to some embodiments;

[0083] Fig.24 depicts an example of a set of altered time domain pulses in a full TD-CRI according to some embodiments;

[0084] Fig.25 depicts another example of a set of altered time domain pulses in a full TD-CRI according to some embodiments;

[0085] Fig.26 depicts an example representation of overlapping coverage areas in a Wi-Fi sensing system according to some embodiments;

[0086] Fig. 27An example of a Wi-Fi sensing system including a plurality of candidate devices is depicted in accordance with some embodiments;

[0087] Fig.28 depicts an example representation of a plurality of links in a sensing space in accordance with some embodiments;

[0088] Fig.29 depicts an example of an updated sensing link established between an access point and a plurality of sensing-capable devices in accordance with some embodiments;

[0089] Fig.30 depicts an example representation of multiple links in a changed sensing space in accordance with some embodiments;

[0090] Fig.31 depicts an example representation of TD-CRI for candidate sensing links for a sampling instance according to some embodiments;

[0091] Fig.32 depicts an example representation of a TD-CRI profile for a candidate sensing link according to some embodiments;

[0092] Fig.33 depicts a flow chart for establishing a plurality of selected sensing links between a selected device from a plurality of candidate devices and an access point in accordance with some embodiments; and

[0093] Fig.34A and Fig.34B Depicted is a flow diagram for establishing a selected candidate sensing link between a selected device among a plurality of candidate devices and an access point in accordance with some embodiments.

[0094] Fig.35A and Fig.35B depicts a flow chart for establishing an updated link set according to some embodiments; and

[0095] Fig.36A and Fig.36B Another flow diagram for establishing an updated link set in accordance with some embodiments is depicted.

[0096] Fig.37 depicts a flow chart for establishing a plurality of representative sensing links between corresponding sensing-capable devices of a plurality of sensing-capable devices and an access point in accordance with some embodiments;

[0097] Fig.38A and Fig.38B depicts a flow chart for establishing a representative sensing link between a corresponding sensing-capable device of a plurality of sensing-capable devices and an access point in accordance with some embodiments; and

[0098] Fig.39A , Fig.39B and Fig.39C Depicted is a flow diagram for establishing a plurality of representative sensing links between corresponding sensing-capable devices of a plurality of sensing-capable devices and an access point in accordance with some embodiments.

[0099] Fig.40A and Fig.40B depicts a flow diagram for establishing a plurality of selected sensing links between selected ones of the candidate devices and an access point in accordance with some embodiments; and

[0100] Fig.41A , Fig.41B and Fig.41C Another flow diagram for establishing a plurality of selected sensing links between selected ones of the candidate devices and an access point is depicted in accordance with some embodiments. DETAILED DESCRIPTION

[0101] Wireless sensing enables a device to obtain sensing measurements of a transmission channel between two or more devices. By executing a wireless sensing program, a device can obtain sensing measurements useful for detecting and tracking environmental changes. In some aspects of the content described herein, a wireless sensing system can be used for various wireless sensing applications by processing wireless signals (e.g., radio frequency (RF) signals) transmitted through the space between wireless communication devices. Example wireless sensing applications include motion detection, which may include the following: detecting the motion of an object in a space, motion tracking, respiration detection, respiration monitoring, presence detection, gesture detection, gesture recognition, human body detection (moving and stationary human body detection), human body tracking, fall detection, speed estimation, intrusion detection, walking detection, step counting, respiration rate detection, apnea estimation, posture change detection, activity recognition, gait rate classification, gesture decoding, sign language recognition, hand tracking, heart rate estimation, respiration rate estimation, room occupancy detection, human body dynamic monitoring and other types of motion detection applications. Other examples of wireless sensing applications include object recognition, voice recognition, keystroke detection and identification, tamper detection, touch detection, attack detection, user authentication, driver fatigue detection, traffic monitoring, smoking detection, campus violence detection, human counting, human recognition, bicycle positioning, human queue estimation, Wi-Fi imaging, and other types of wireless sensing applications. For example, the wireless sensing system can operate as a motion detection system to detect the presence and location of motion based on Wi-Fi signals or other types of wireless signals. As described in more detail below, the wireless sensing system can be configured to control measurement rates, wireless connections, and device participation, for example, to improve system operation or achieve other technical advantages. In an example where the wireless sensing system is used for another type of wireless sensing application, the system improvements and technical advantages achieved when the wireless sensing system is used for motion detection are also achieved.

[0102] In some example wireless sensing systems, the wireless signal contains a component that the wireless device can use to estimate the channel response or other channel information (e.g., a synchronization preamble in a Wi-Fi PHY frame, or another type of component), and the wireless sensing system can detect motion (or another characteristic depending on the wireless sensing application) by analyzing changes in the channel information collected over time. In some instances, the wireless sensing system can operate similar to a bistatic radar system, where a Wi-Fi access point (AP) assumes the role of a receiver and each Wi-Fi device (station (STA), node, or peer) connected to the AP assumes the role of a transmitter. The wireless sensing system can trigger the connected device to generate a transmission and produce channel response measurements at the receiver device. This triggering process can be repeated periodically to obtain a series of time-varying measurements. The wireless sensing algorithm can then receive the time series of generated channel response measurements (e.g., calculated by a Wi-Fi receiver) as input, and through a correlation or filtering process, a determination can then be made (e.g., determining whether there is motion within the environment represented by the channel response based on changes or patterns in the channel estimate, for example). In instances where the wireless sensing system detects motion, the location of the motion within the environment may also be identified based on the motion detection results in the plurality of wireless devices.

[0103] Therefore, the wireless signals received at each wireless communication device in the wireless communication device in the wireless communication network can be analyzed to determine the channel information of various communication links (located between the corresponding wireless communication device pairs) in the network. The channel information can represent the physical medium of the wireless signal that applies the transfer function to the space. In some cases, the channel information includes a channel response. The channel response can characterize the physical communication path, representing the combined effects of scattering, fading and power attenuation in the space between the transmitter and the receiver, for example. In some cases, the channel information includes beamforming state information (e.g., feedback matrix, steering matrix, channel state information, etc.) provided by the beamforming system. Beamforming is a signal processing technique usually used for directional signal transmission or reception in a multi-antenna (multiple input / multiple output (MIMO)) radio system. Beamforming can be achieved by operating the elements in the antenna array in a manner such that the signals at some angles experience constructive interference, while the signals at other angles experience destructive interference.

[0104] The channel information of each of the communication links may be analyzed (e.g., by a hub device or other device in a wireless communication network, or a sensing transmitter, a sensing receiver, or a sensing initiator communicatively coupled to the network) to, for example, detect whether motion has occurred in the space, determine the relative position of the detected motion, or both. In some aspects, the channel information of each of the communication links may be analyzed to detect whether an object is present, for example, when no motion is detected in the space.

[0105] In some cases, the wireless sensing system can control the node measurement rate. For example, the Wi-Fi motion system can configure variable measurement rates (e.g., channel estimation / environmental measurement / sampling rate) based on the standards given by current wireless sensing applications (e.g., motion detection). In some embodiments, for example, when there is no motion or no motion is detected for a period of time, the wireless sensing system can reduce the rate of measuring the environment so that the connected device is triggered or the frequency of sensing transmission or sensing measurement is reduced. In some embodiments, for example, when there is motion, the wireless sensing system can increase the trigger rate or the sensing transmission rate or the sensing measurement rate to produce a time series of measurement results with finer time resolution. Controlling the variable sensing measurement rate can achieve energy saving (via device triggering), reduce processing (reduce the data to be associated or filtered), and improve resolution during a specified time period.

[0106] In some cases, the wireless sensing system can perform band steering or client steering for nodes throughout the wireless network, for example, in a Wi-Fi multi-AP or extended service set (ESS) topology, multiple coordinated wireless APs each provide a basic service set (BSS) that can occupy different frequency bands and allow devices to transparently move from one participating AP to another participating AP (e.g., mesh). For example, in a home mesh network, a Wi-Fi device can connect to any of the APs, but typically selects an AP with good signal strength. The coverage footprint of mesh APs typically overlaps, typically placing each device within communication range or within more than one AP. If the AP supports multiple frequency bands (e.g., 2.4 GHz and 5 GHz), the wireless sensing system can keep the device connected to the same physical AP, but instruct the wireless sensing system to use different frequency bands to obtain more diverse information, thereby helping to improve the accuracy or results of wireless sensing algorithms (e.g., motion detection algorithms). In some embodiments, the wireless sensing system can change a device from connecting to one mesh AP to connecting to another mesh AP. Such device steering may be performed, for example, based on criteria detected in a particular area during wireless sensing (eg, motion detection) to improve detection coverage or better locate motion within an area.

[0107] In some cases, beamforming can be performed between wireless communication devices based on some knowledge of the communication channel (e.g., through feedback properties generated by the receiver), which can be used to generate one or more steering properties (e.g., steering matrices) applied by the transmitter device to shape the transmitted beam / signal in one or more specific directions. Thus, changes in the steering or feedback properties used in the beamforming process indicate changes in the space accessed by the wireless communication system that may be caused by moving objects. For example, motion can be detected by substantial changes in the communication channel over a period of time, for example, as indicated by the channel response, or the steering or feedback properties, or any combination thereof.

[0108] In some embodiments, for example, a steering matrix can be generated at a transmitter device (beamforming transmitting end) based on a feedback matrix provided by a receiver device (beamforming receiving end) based on channel sounding. Because the steering matrix and the feedback matrix are related to the propagation characteristics of the channel, these matrices change as the object moves within the channel. Changes in channel characteristics are reflected in these matrices accordingly, and by analyzing the matrices, motion can be detected and different characteristics of the detected motion can be determined. In some embodiments, a spatial map can be generated based on one or more beamforming matrices. The spatial map can indicate the approximate direction of an object in space relative to a wireless communication device. In some cases, many beamforming matrices (e.g., feedback matrices or steering matrices) can be generated to represent multiple directions in which an object can be positioned relative to a wireless communication device. These many beamforming matrices can be used to generate a spatial map. The spatial map can be used to detect the presence of motion in space or to detect the location of a detected motion.

[0109] In some cases, the motion detection system can control the variable device measurement rate during the motion detection process. For example, a feedback control system for a multi-node wireless motion detection system can adaptively change the sampling rate based on environmental conditions. In some cases, such control can improve the operation of the motion detection system or provide other technical advantages. For example, the measurement rate can be controlled in a manner that optimizes or otherwise improves the use of air interface time relative to the detection capability applicable to a wide range of different environments and different motion detection applications. The measurement rate can be controlled in a manner that reduces the redundant measurement data to be processed, thereby reducing the processor load / power requirements. In some cases, the measurement rate is controlled in an adaptive manner, for example, adaptive sampling can be controlled separately for each participating device. The adaptive sampling rate can be used for different use cases or device characteristics together with a tuning control loop.

[0110] In some cases, the wireless sensing system may allow a device to dynamically indicate its wireless sensing capability or willingness to sense wirelessly and transmit it to the wireless sensing system. For example, sometimes a device may not want to be periodically interrupted or triggered to transmit a wireless signal that will allow the AP to generate channel measurements. For example, if the device is in a sleep state, frequently waking up the device to transmit or receive wireless sensing signals may consume resources (e.g., causing the cell phone battery to discharge faster). These and other events may make the device willing or unwilling to participate in the wireless sensing system operation. In some cases, a cell phone running on a battery may not want to participate, but when the cell phone is plugged into a charger, the cell phone may be willing to participate. Therefore, if the cell phone is unplugged, the wireless sensing system may be indicated to exclude the cell phone from participating; and if the cell phone is plugged in, the wireless sensing system may be indicated to include the cell phone in the wireless sensing system operation. In some cases, if the device is under load (e.g., the device is streaming audio or video) or is busy performing a primary function, the device may not want to participate; and when the load of the same device is reduced and participation does not interfere with the primary function, the device can indicate to the wireless sensing system that it is willing to participate.

[0111] An example wireless sensing system is described below in the context of motion detection (detecting motion of objects in space, motion tracking, respiration detection, respiration monitoring, presence detection, gesture detection, gesture recognition, human detection (moving and stationary human detection), human tracking, fall detection, speed estimation, intrusion detection, walking detection, step counting, respiration rate detection, apnea estimation, posture change detection, activity recognition, gait rate classification, gesture decoding, sign language recognition, hand tracking, heart rate estimation, respiration rate estimation, room occupancy detection, human dynamics monitoring, and other types of motion detection applications). However, the operations, system improvements, and technical advantages achieved when the wireless sensing system operates as a motion detection system are also applicable to instances where the wireless sensing system is used for another type of wireless sensing application.

[0112] In various embodiments of the present disclosure, non-limiting definitions of one or more terms that will be used in the description are provided below.

[0113] The term "measurement campaign" may refer to a bidirectional series of one or more sensing transmissions between a sensing receiver and a sensing transmitter that allows a series of one or more sensing measurements to be calculated.

[0114] A wireless access point (WAP) or simply access point (AP) is a networking device in a WLAN network that allows other networking devices in the WLAN network to connect to a wired network. In an example, an AP creates a wireless local area network.

[0115] A station (STA) is any device connected to a WLAN network and having an 802.11-compatible MAC and PHY interface with a wireless medium. A STA can be a laptop, desktop computer, smartphone, or smart appliance. A STA can be fixed, mobile, or portable. A STA that does not act as an AP role can be referred to as a non-AP STA.

[0116] The term "transmission opportunity (TXOP)" may refer to a negotiated time interval during which a particular quality of service (QoS) station (e.g., a STA, an AP, or a STA or AP, e.g., acting as a sensing initiator, a sensing responder, a sensing transmitter, or a sensing receiver) may have the right to initiate frame exchanges on the wireless medium. The QoS access category (AC) of the transmission opportunity may be requested as part of a service or session negotiation. In an example, a TXOP may be a time period for transmission (e.g., data transmission or sensing transmission).

[0117] The term "Quality of Service (QoS) Access Category (AC)" may refer to an identifier of a frame that classifies the transmission priority required for the frame. In one example, four QoS access categories are defined, namely, AC_VI: video service; AC_VO: voice service; AC_BE: best effort transmission and AC_BK: background traffic. In addition, each QoS access category may have different TXOP parameters defined therefor.

[0118] The term "Short Interframe Space (SIFS)" may refer to a period of time during which a processing element (e.g., a microprocessor, dedicated hardware, or any such element) within a device of a Wi-Fi sensing system is able to process data presented to it in a frame. In one example, the short interframe space may be 10 milliseconds.

[0119] The term "PHY layer protocol data unit (PPDU)" may refer to a data unit including a preamble and a data field. The preamble field may contain transmission vector format information, and the data field may contain a payload and a higher layer header.

[0120] The term "Null Data PPDU (NDP)" may refer to a PPDU that does not contain a data field. In one example, a Null Data PPDU may be used for a sensing transmission, where the MAC header of the NDP contains information required by a sensing receiver to perform sensing measurements on the sensing transmission.

[0121] The term "transmission parameters" may refer to a set of IEEE 802.11 PHY transmitter configuration parameters that are defined as part of a transmission vector (TXVECTOR) corresponding to a specific PHY and may be configured for each PHY layer PPDU transmission or each Null Data PPDU (NDP) transmission.

[0122] The term "resource unit (RU)" may refer to an allocation of an Orthogonal Frequency Division Multiplexing (OFDM) channel that may be used to carry a modulated signal. Depending on the mode of the modem, a RU may contain a variable number of carriers.

[0123] The term "sensing target" may refer to the target of a sensing activity. A sensing target is not static and may change from time to time. In an example, a sensing target may require sensing measurements of a specific type, a specific format, or a specific precision, resolution, or accuracy that are usable by a sensing algorithm.

[0124] The term "sensing space" may refer to any physical space in which a Wi-Fi sensing system may operate.

[0125] The term "sensing measurement result" may refer to a measurement result of a wireless channel state between a transmitter device (e.g., a sensing transmitter) and a receiver device (e.g., a sensing receiver) derived from a sensing transmission. In one example, the sensing measurement result may also be referred to as a channel response measurement result.

[0126] The term "sensing algorithm" may refer to a computational algorithm that implements a sensing goal. The sensing algorithm may be executed on any device in a Wi-Fi sensing system.

[0127] A sensing receiver is a station (STA) that receives a sensing transmission (e.g., a PPDU or any other transmission containing a data transmission that may be opportunistically used as a sensing transmission) sent by a sensing transmitter and performs sensing measurements as part of a WLAN sensing procedure. An AP is an example of a sensing receiver. In some examples, a STA may also be a sensing receiver.

[0128] A sensing transmitter is a station (STA) that sends a sensing transmission (e.g., PPDU or any other transmission) for sensing measurement results (e.g., channel state information) in a WLAN sensing procedure. In one example, a STA is an example of a sensing transmitter. In some examples, an AP can be a sensing transmitter for Wi-Fi sensing purposes, such as where a STA acts as a sensing receiver.

[0129] The sensing initiator is a station (STA) that initiates the WLAN sensing procedure. The role of the sensing initiator can be assumed by a sensing receiver, a sensing transmitter, or a separate device (eg, a remote processing device) that contains a sensing algorithm.

[0130] A sensing responder is a station (STA) that participates in a WLAN sensing procedure initiated by a sensing initiator. The role of a sensing responder can be assumed by a sensing receiver, a sensing transmitter, or a separate device (e.g., a remote processing device) that contains a sensing algorithm. In an example, multiple sensing responders can participate in a Wi-Fi sensing session.

[0131] The algorithm agent can be part of the sensing algorithm. In an example, the algorithm agent can discover a sensing initiator that is part of a Wi-Fi sensing system. In some examples, the algorithm agent can report sensing results generated by the sensing algorithm and available to Wi-Fi devices.

[0132] An initiator agent may be run on a device capable of acting as a sensing initiator. In an instance where there are multiple Wi-Fi devices in a Wi-Fi sensing system capable of acting as a sensing initiator, an instance of the initiator agent may be run on each of the multiple Wi-Fi devices. The initiator agent may be configured to discover one or more sensing responders and details of the one or more sensing responders (e.g., whether they are associated with a sensing initiator or whether they actively generate sensing measurements with the sensing initiator), and the initiator agent may open a sensing session with the one or more sensing responders. In an instance, the initiator agent may declare that its host device is capable of becoming a sensing initiator. The initiator agent may discover the capabilities of the sensing responders with which the initiator agent can open a sensing session. In an instance, the initiator agent may request a capability report from the sensing responder.

[0133] The responder proxy may run on a device capable of acting as a sensing responder. In instances where there are multiple Wi-Fi devices in a Wi-Fi sensing system capable of acting as sensing responders, an instance of the responder proxy may run on each of the multiple Wi-Fi devices. The responder proxy may report its presence in the Wi-Fi sensing system and may report the capabilities of the sensing responder.

[0134] The term "sensing-capable device" may refer to a device that is capable of participating in a sensing session. In one example, a sensing-capable device may be an AP or a non-AP STA. The role of a sensing-capable device may be assumed by a sensing receiver, a sensing transmitter, or a separate device (e.g., a remote processing device) that includes a sensing algorithm.

[0135] The term "sensing transmission" may refer to any transmission from a sensing transmitter to a sensing receiver that may be used to make a sensing measurement. In one example, the sensing transmission may also be referred to as a wireless sensing signal or a wireless signal.

[0136] The term "sensing trigger message" may refer to a message sent from a sensing initiator to a sensing transmitter to initiate or trigger one or more sensing transmissions.

[0137] The term "sensing response message" may refer to a message contained within a sensing transmission from a sensing transmitter to a sensing receiver. The sensing receiver may use the sensing transmission containing the sensing response message to perform sensing measurements.

[0138] The term "sensing response announcement" may refer to a message contained within a sensing transmission from a sensing transmitter to a sensing receiver that announces that a sensing response NDP will follow within a short interframe space (SIFS). An example of a sensing response announcement is an NDP announcement or NDPA. In an example, a sensing response NDP may be transmitted using the requested transmission configuration.

[0139] The term "sensing announcement" may refer to a message contained within a sensing transmission from a sensing transmitter to a sensing receiver that announces that a sensing NDP will follow within a short interframe space (SIFS). An example of a sensing announcement is an NDP announcement or NDPA. In an example, a sensing NDP may be transmitted using a requested transmission configuration.

[0140] The term "sensing response NDP" or "sensing NDP" may refer to a response transmitted by a sensing transmitter and used for sensing measurements at a sensing receiver. In an example, a sensing response NDP may be used when the requested transmission configuration is incompatible with the transmission parameters required for successful non-sensing message reception. The sensing response NDP may be advertised via a sensing response announcement. In an example, the sensing response NDP may be implemented with an empty data PPDU. In some examples, the sensing response NDP may be implemented with a frame that does not contain any data.

[0141] A "transmission channel" may refer to a tunable channel on which a sensing receiver performs sensing measurements and / or on which a sensing transmitter performs sensing transmissions.

[0142] The term “clear to send (CTS)” may refer to a function that may be used to let an AP know that a STA is ready (or allowed if there is no channel conflict) to send or receive data.

[0143] The term "link" may refer to a connection between a sensing-capable device and an access point, and may be represented as "Ln", where "n" is defined as a link number. In one example, multiple links may be numbered by link number as L1, L2, ..., Ln.

[0144] The term "sensing link" may refer to a link between a sensing-capable device and an access point that may be used for sensing transmissions.

[0145] The term "fine tuning link" may refer to a link between a sensing-capable device and an access point that is not selected for sensing transmissions.

[0146] The term “sensing link set” may refer to a steady-state sensing link set of a Wi-Fi system at a given point in time.

[0147] The term "candidate sensing link" may refer to a link between a sensing-capable device and an access point that is not currently used for sensing transmissions but may be used for sensing transmissions later.

[0148] The term "link combination" may be defined as a group of links that have a large coverage overlap in physical space. Due to the coverage overlap, one link of the link combination may be used for sensing measurements.

[0149] The term "essential link" may refer to a link that has no overlapping coverage area or has minimal overlapping coverage area with other links.

[0150] The term "sampling instance" may be defined as an instance (or small time period) at which a receiver samples (or measures) one or more sensing transmissions from one or more links. A sampling instance may be denoted as "s".

[0151] The term "coverage area" may refer to an area where motion may be detected through sensing transmissions between sensing-capable devices and access points.

[0152] The term "analysis period" may refer to a period that includes multiple sampling instances for sensing link analysis.

[0153] The term "average received power" may refer to the power P0 of the link received at the receiver without any motion in the sensing space, so that the power will be stable as long as the topology of the sensing space does not change.

[0154] The term "power variation of a link" can be defined as the difference between the received power at a sampling instance P(s) of the link and the average received power of the link, i.e., p(s) = P0-P(s). If motion affects the received power of multiple links at the same sampling instance s, the affected received power can be defined as the "power variation of the link combination".

[0155] The "Combo or Not" parameter may be used to indicate whether the power change affects a single link (Not) or more than one link (Combo).

[0156] The term "variation counter" may be defined as the number of occurrences of a particular power variation of a link or link combination during all sampling instances in an analysis period.

[0157] The term "train" may refer to power variations of a link or combination of links occurring at consecutive sampling instances.

[0158] The term "string counter" may be defined as the number of times a power change of a link or combination of links occurs within a string.

[0159] The term "string length" may be defined as the value of the final string counter of a string.

[0160] The term "maximum string length" may be defined as the maximum number of string lengths.

[0161] The term "in-combo counter" for a link may be defined as the number of times the link appears in all power variations of the link combination during all sampling instances in the analysis period.

[0162] The term "combined link" may be defined as any link that is part of at least one power variation of a link combination.

[0163] The term "combination length" may be defined as the number of links in a power variation of a link combination.

[0164] The term "power variation test set" may refer to a power variation set of link combinations selected for analysis to determine which links are selected as sensing links.

[0165] "Sensing spatial coverage metric" may refer to the parameters and methods used to determine which links to select as sensing links from a power variation test set.

[0166] The term "single link power variation" may refer to a power variation of a link within a link combination.

[0167] The term "data link" may refer to a link between a sensing-capable device and an access point for data transmission.

[0168] The term "candidate link" may refer to a link that may be established between a sensing-capable device and an access point for sensing transmissions but that was not used for sensing transmissions prior to an analysis period.

[0169] The term "candidate link set" may refer to a group of candidate links.

[0170] The term "evaluate link" may refer to a link established between a sensing-capable device and an access point that is evaluated during an analysis period.

[0171] The term "evaluation link set" may refer to a group of evaluation links being evaluated to determine whether one or more of the links can be fine-tuned to form a sensing link set at the end of an analysis period. The evaluation link set may contain the sensing link set established when the analysis period begins.

[0172] The term "idle sensing-capable device" may refer to a sensing-capable device that is capable of participating in a sensing session or a data session but is not currently in an active sensing or data session.

[0173] The term "channel representation information (CRI)" may refer to a collection of sensing measurements that together represent the state of a channel between two devices. Examples of CRI are channel state information (CSI) and full time domain channel representation information (full TD-CRI).

[0174] The term "channel state information (CSI)" may refer to a property of a communication channel that is either known or measured through channel estimation techniques.

[0175] The term "time domain channel representation information (TD-CRI)" may be a series of complex time domain pulse pairs created by performing an inverse fast Fourier transform (IFFT) on CSI values ​​(eg, CSI calculated by a baseband receiver processor).

[0176] The term "sensing measurement poll" may refer to a message sent from a sensing transmitter to a sensing receiver to request transmission of channel representative information that has been determined by the sensing receiver.

[0177] The term "reconstructed filtered time-domain channel representation information (reconstructed filtered TD-CRI)" may refer to a version of the full TD-CRI created from the filtered TD-CRI.

[0178] The term "full time domain channel representation information (full TD-CRI)" may refer to a series of complex time domain pulse pairs created by performing an inverse fast Fourier transform (IFFT) on CSI values ​​(eg, CSI calculated by a baseband receiver).

[0179] The term "filtered time domain channel representation information (filtered TD-CRI)" may refer to a condensed series of complex time domain pulse pairs created by applying an algorithm to the full TD-CRI. The algorithm may select some time domain pulses and reject other time domain pulses. The filtered TD-CRI contains information correlating the selected time domain pulses with corresponding time domain pulses in the full TD-CRI.

[0180] The term "channel representation information transmission message" may refer to a message sent by a sensing receiver that has performed sensing measurements on a sensing transmission, wherein the sensing receiver sends a CRI to a sensing initiator or a sensing algorithm manager.

[0181] The term "reconstructed CSI (R-CSI)" may refer to a representation of the original CSI values ​​as measured by a baseband receiver, where the R-CSI is calculated by taking the original CSI values ​​(frequency domain), performing an IFFT to convert those values ​​to the time domain, selecting a number of time domain pulses, nulling or zeroing the time domain tones excluding the selected time domain pulses, and performing an FFT. The resulting frequency domain complex value is the R-CSI.

[0182] The term "sensing footprint" may refer to a steady-state or semi-static representation of a propagation channel between a sensing receiver and a sensing transmitter in a sensing space computed by the sensing receiver in the form of a time-domain channel impulse response.

[0183] The term "delivered transmission configuration" may refer to transmission parameters applied by a sensing transmitter for a sensing transmission.

[0184] The term "requested transmission configuration" may refer to requested transmission parameters of a sensing transmitter to be used when sending a sensing transmission.

[0185] The term "footprint delta" may refer to a single-dimensional matrix of complex values ​​representing the difference between a time-domain channel impulse response generated by converting CSI measurements to the time domain using an IFFT and a stored sensing footprint.

[0186] The term "measurement footprint delta threshold" may refer to a minimum difference between a TD-CRI value and a corresponding sensing footprint value for which a sensing receiver or a sensing algorithm manager considers that there is a change in the propagation characteristics of a propagation channel.

[0187] The term "measurement footprint increment count" may refer to the number of times a measurement footprint increment threshold is exceeded before a sensing receiver or a sensing algorithm manager deems that there is a change in the propagation characteristics of a propagation channel.

[0188] The term "footprint delta derivative period" may refer to the period that a footprint delta derivative must remain below a footprint delta derivative threshold before a sensing receiver or sensing algorithm manager may determine that a new sensing footprint needs to be calculated.

[0189] The term "imprint delta derivative" may refer to the rate at which the imprint delta changes over one or more pitches and one or more frames.

[0190] The term "imprint delta derivative threshold" may refer to the maximum value of the velocity footprint delta derivative at which a sensing receiver or sensing algorithm manager considers that there is ongoing movement or motion in the sensing space. If the footprint delta derivative drops below the footprint delta derivative threshold, the sensing receiver or sensing algorithm manager may determine that a new sensing footprint needs to be calculated.

[0191] The term “steady state footprint delta threshold” may refer to the maximum difference between a TD-CRI value and a corresponding sensing footprint value at which the sensing receiver or sensing algorithm manager considers that the TD-CRI has not returned to its steady state (ie, the stored sensing footprint).

[0192] The term "sensing footprint average count" may refer to a plurality of sensing measurements that may be averaged to generate a sensing footprint.

[0193] The term "analysis period" may be defined as a period consisting of a number of sampling instances for sensing link analysis. Typically, an analysis period may be long, covering in instances an hour, half a day, a day, or longer.

[0194] The term "TD-CRI profile" is the TD-CRI at the output of the filter window.

[0195] The term "filter window" is the time period over which a stable TD-CRI profile is generated. In an example, the filter window may consist of multiple TD-CRI sampling instances. For example, since CSI is generated from a 64-point FFT in the frequency domain, the filter window may be set to 64 TD-CRI sampling instances.

[0196] The term "TD-CRI profile set" is a collection of TD-CRI profiles for a link within an analysis period.

[0197] The term "phase shift" may be the difference between the actual phase of the TD-CRI without the receiver time delay and the phase of the TD-CRI with the receiver time delay. The phase shift may also be referred to as a time shift.

[0198] The term "wireless local area network (WLAN) sensing session" or "Wi-Fi sensing session" may refer to a period of time during which objects in a physical space may be detected, detected, and / or characterized. In one example, during a WLAN sensing session, several devices participate and thereby contribute to the generation of sensing measurements. In one example, measurement activities may be performed within a WLAN sensing session.

[0199] For the purpose of reading the description of the following various embodiments, the following description of the various parts of the specification and their corresponding contents may be helpful:

[0200] Section A describes wireless communication systems, wireless transmissions, and sensing measurements that can be used to practice the embodiments described herein.

[0201] Section B describes systems and methods useful for a wireless sensing system configured to send sensing transmissions and make sensing measurements.

[0202] Section C describes embodiments of systems and methods for selecting a set of probe devices for Wi-Fi sensing.

[0203] A. Wireless communication systems, wireless transmission and sensing measurements

[0204] Figure 1A wireless communication system 100 is shown. The wireless communication system 100 includes three wireless communication devices: a first wireless communication device 102A, a second wireless communication device 102B, and a third wireless communication device 102C. The wireless communication system 100 may include additional wireless communication devices and other components (e.g., additional wireless communication devices, one or more network servers, network routers, network switches, cables or other communication links, etc.).

[0205] The wireless communication devices 102A, 102B, 102C may operate in a wireless network, for example, in accordance with a wireless network standard or another type of wireless communication protocol. For example, the wireless network may be configured to operate as a wireless local area network (WLAN), a personal area network (PAN), a metropolitan area network (MAN), or another type of wireless network. Examples of WLANs include networks configured to operate in accordance with one or more standards in the 802.11 family of standards developed by the IEEE (e.g., Wi-Fi networks), etc. Examples of PANs include networks configured to operate in accordance with short-range communication standards (e.g., Networks that operate with near field communication (NFC), ZigBee), millimeter wave communication, etc.

[0206] In some embodiments, the wireless communication devices 102A, 102B, 102C may be configured to communicate in a cellular network, for example, according to a cellular network standard. Examples of cellular networks include networks configured according to 2G standards such as Global System for Mobile (GSM) and Enhanced Data Rates for GSM Evolution (EDGE) or EGPRS; 3G standards such as Code Division Multiple Access (CDMA), Wideband Code Division Multiple Access (WCDMA), Universal Mobile Telecommunications System (UMTS), and Time Division Synchronous Code Division Multiple Access (TD-SCDMA); 4G standards such as Long Term Evolution (LTE) and Advanced LTE (LTE-A); 5G standards, etc.

[0207] exist Figure 1In the example shown, the wireless communication devices 102A, 102B, 102C may be standard wireless network components, or the wireless communication devices may include standard wireless network components. For example, the wireless communication devices 102A, 102B, 102C may be commercially available Wi-Fi APs or another type of wireless access point (WAP) that performs one or more operations as described herein embedded as instructions (e.g., software or firmware) on a modem of the WAP. In some cases, the wireless communication devices 102A, 102B, 102C may be nodes of a wireless mesh network, such as commercially available mesh network systems (e.g., Plume Wi-Fi, Google Wi-Fi, Qualcomm Wi-Fi SoN, etc.). In some cases, another type of standard or conventional Wi-Fi transmitter device may be used. In some cases, one or more of the wireless communication devices 102A, 102B, 102C may be implemented as a WAP in a mesh network, while other wireless communication devices 102A, 102B, 102C are implemented as leaf devices (e.g., mobile devices, smart devices, etc.) that access the mesh network through one of the WAPs. In some cases, one or more of the wireless communication devices 102A, 102B, 102C are mobile devices (e.g., smart phones, smart watches, tablet computers, laptop computers, etc.), wireless-enabled devices (e.g., smart thermostats, Wi-Fi-enabled cameras, smart TVs), or another type of device that communicates in a wireless network.

[0208] The wireless communication devices 102A, 102B, 102C may be implemented without a Wi-Fi component; for example, other types of standard or non-standard wireless communications may be used for motion detection. In some cases, the wireless communication devices 102A, 102B, 102C may be a dedicated motion detection system, or the wireless communication devices may be part of a dedicated motion detection system. For example, a dedicated motion detection system may include a hub device and one or more beacon devices (as remote sensor devices), and the wireless communication devices 102A, 102B, 102C may be the hub device or the beacon device in the motion detection system.

[0209] like Figure 1 As shown, the wireless communication device 102C includes a modem 112, a processor 114, a memory 116, and a power supply unit 118; any wireless communication device 102A, 102B, 102C in the wireless communication system 100 may include the same, additional, or different components, and the components may be configured as follows. Figure 1In some embodiments, the modem 112, processor 114, memory 116, and power supply unit 118 of the wireless communication device are housed together in a common housing or other assembly. In some embodiments, one or more of the components of the wireless communication device may be housed separately, for example, in separate housings or other assemblies.

[0210] The modem 112 may communicate (receive, transmit, or both) wireless signals. For example, the modem 112 may be configured to communicate RF signals formatted according to a wireless communication standard (e.g., Wi-Fi or Bluetooth). The modem 112 may be implemented as Figure 1 The example wireless network modem 112 shown may be implemented in another way, such as by using other types of components or subsystems. In some embodiments, the modem 112 includes a radio subsystem and a baseband subsystem. In some cases, the baseband subsystem and the radio subsystem may be implemented on a common chip or chipset, or the baseband subsystem and the radio subsystem may be implemented in a card or another type of assembled device. The baseband subsystem may be coupled to the radio subsystem, for example, by leads, pins, wires, or other types of connections.

[0211] In some cases, the radio subsystem in modem 112 may include one or more antennas and RF circuit systems. The RF circuit system may include, for example, a circuit system for filtering, amplifying or otherwise adjusting an analog signal, a circuit system for up-converting a baseband signal to an RF signal, a circuit system for down-converting an RF signal to a baseband signal, etc. Such circuit systems may include, for example, filters, amplifiers, mixers, local oscillators, etc. The radio subsystem may be configured to transmit a radio frequency wireless signal on a wireless communication channel. For example, the radio subsystem may include a radio chip, an RF front end, and one or more antennas. The radio subsystem may include additional or different components. In some embodiments, the radio subsystem may be or may include a radio electronic device (e.g., an RF front end, a radio chip, or similar components) from a conventional modem (e.g., from a Wi-Fi modem, a micro base station modem, etc.). In some embodiments, the antenna includes multiple antennas.

[0212] In some cases, the baseband subsystem in modem 112 may include, for example, a digital electronic device configured to process digital baseband data. For example, the baseband subsystem may include a baseband chip. The baseband subsystem may include additional or different components. In some cases, the baseband subsystem may include a digital signal processor (DSP) device or another type of processor device. In some cases, the baseband system includes digital processing logic to operate a radio subsystem, transmit wireless network traffic through the radio subsystem, detect motion based on a motion detection signal received by the radio subsystem, or perform other types of processes. For example, the baseband subsystem may include one or more chips, chipsets, or other types of devices, which are configured to encode signals and deliver the encoded signals to the radio subsystem for transmission, or identify and analyze data encoded in the signal from the radio subsystem (e.g., by decoding the signal according to a wireless communication standard, by processing the signal according to a motion detection process, or by other means).

[0213] In some cases, the radio subsystem in modem 112 receives a baseband signal from a baseband subsystem, up-converts the baseband signal to an RF signal, and wirelessly transmits the RF signal (e.g., via an antenna). In some cases, the radio subsystem in modem 112 receives an RF signal wirelessly (e.g., via an antenna), down-converts the RF to a baseband signal, and sends the baseband signal to the baseband subsystem. The signals exchanged between the radio subsystem and the baseband subsystem may be digital signals or analog signals. In some instances, the baseband subsystem includes a conversion circuit system (e.g., a digital-to-analog converter, an analog-to-digital converter) and exchanges analog signals with the radio subsystem. In some instances, the radio subsystem includes a conversion circuit system (e.g., a digital-to-analog converter, an analog-to-digital converter) and exchanges digital signals with the baseband subsystem.

[0214] In some cases, the baseband subsystem of modem 112 can transmit wireless network traffic (e.g., data packets) in the wireless communication network through the radio subsystem on one or more network traffic channels. The baseband subsystem of modem 112 can also transmit or receive (or both) signals (e.g., motion detection signals or motion detection signals) through the radio subsystem on a dedicated wireless communication channel. In some cases, the baseband subsystem generates a motion detection signal for transmission, such as to detect motion in space. In some cases, the baseband subsystem processes the received motion detection signal (a signal based on the motion detection signal transmitted through space), such as to detect the motion of an object in space.

[0215] Processor 114 can execute instructions, for example, to generate output data based on data input. Instructions can include programs, codes, scripts or other types of data stored in memory. Additionally or alternatively, instructions can be encoded as pre-programmed or reprogrammable logic circuits, logic gates or other types of hardware or firmware components. Processor 114 can be or include a general-purpose microprocessor, such as a dedicated coprocessor or another type of data processing device. In some cases, processor 114 performs high-level operations of wireless communication device 102C. For example, processor 114 can be configured to execute or interpret software, scripts, programs, functions, executable files or other instructions stored in memory 116. In some embodiments, processor 114 can be included in modem 112.

[0216] The memory 116 may include a computer-readable storage medium, such as a volatile memory device, a non-volatile memory device, or both. The memory 116 may include one or more read-only memory devices, random access memory devices, buffer memory devices, or a combination of these and other types of memory devices. In some cases, one or more components of the memory may be integrated with or otherwise associated with another component of the wireless communication device 102C. The memory 116 may store instructions that may be executed by the processor 114. For example, the instructions may include instructions for using an interference buffer and a motion detection buffer to time-align signals as by one or more of the operations of the example processes disclosed herein.

[0217] The power supply unit 118 provides power to other components of the wireless communication device 102C. For example, the other components may operate based on power provided by the power supply unit 118 through a voltage bus or other connection. In some embodiments, the power supply unit 118 includes a battery or battery system, such as a rechargeable battery. In some embodiments, the power supply unit 118 includes an adapter (e.g., an alternating current (AC) adapter) that receives an external power signal (from an external source) and converts the external power signal to an internal power signal regulated for the components of the wireless communication device 102C. The power supply unit 118 may include other components or operate in another manner.

[0218] exist Figure 1In the example shown, wireless communication devices 102A, 102B transmit wireless signals (e.g., according to a wireless network standard, motion detection protocol, or other). For example, wireless communication devices 102A, 102B may broadcast wireless motion detection signals (e.g., reference signals, beacon signals, status signals, etc.), or the wireless communication devices may send wireless signals addressed to other devices (e.g., user equipment, client devices, servers, etc.), and other devices (not shown) and wireless communication device 102C may receive the wireless signals transmitted by wireless communication devices 102A, 102B. In some cases, the wireless signals transmitted by wireless communication devices 102A, 102B are repeated periodically, such as according to wireless communication standards or other conditions.

[0219] In the example shown, the wireless communication device 102C processes the wireless signals from the wireless communication devices 102A, 102B to detect the motion of an object in the space accessed by the wireless signals, determine the location of the detected motion, or both. For example, the wireless communication device 102C may perform the following steps with respect to Fig.33 , Fig.34A , Fig.34B , Fig.35A , Fig.35B , Fig.36A , Fig.36B , Fig.37 , Fig.38A , Fig.38B , Fig.39A , Fig.39B , Fig.39C , Fig.40A , Fig.40B , Fig.41A , Fig.41B , Fig.41C One or more operations of the described example processes or another type of process for detecting motion or determining the location of detected motion. The space accessed by the wireless signal can be an indoor or outdoor space, which can include, for example, one or more fully or partially enclosed areas, open areas without enclosures, etc. The space can be or can include the interior of a room, multiple rooms, a building, etc. In some cases, the wireless communication system 100 can be modified, for example, so that the wireless communication device 102C can transmit wireless signals, and the wireless communication devices 102A, 102B can process the wireless signals from the wireless communication device 102C to detect motion or determine the location of detected motion.

[0220] The wireless signal used for motion detection may include, for example, a beacon signal (e.g., a Bluetooth beacon, a Wi-Fi beacon, other wireless beacon signals), another standard signal generated for other purposes according to a wireless network standard, or a non-standard signal generated for motion detection or other purposes (e.g., a random signal, a reference signal, etc.). In an example, motion detection may be performed by analyzing one or more training fields carried by the wireless signal or by analyzing other data carried by the signal. In some examples, data will be added for the explicit purpose of motion detection, or the data used will nominally be used for another purpose and reused or reused for motion detection purposes. In some examples, the wireless signal propagates through an object (e.g., a wall) before or after interacting with a mobile object, which may allow the movement of the mobile object to be detected without an optical line of sight between the mobile object and the transmission or reception hardware. Based on the received signal, the wireless communication device 102C may generate motion detection data. In some cases, the wireless communication device 102C may transmit the motion detection data to another device or system, such as a security system, which may include a control center for monitoring movement within a space such as a room, a building, an outdoor area, etc.

[0221] In some embodiments, the wireless communication devices 102A, 102B may be modified to transmit a motion detection signal (which may include, for example, a reference signal, a beacon signal, or another signal for detecting motion space) on a wireless communication channel (e.g., a frequency channel or a coding channel) that is separate from the wireless network traffic signal. For example, the modulation applied to the payload of the motion detection signal and the type of data or data structure in the payload may be known by the wireless communication device 102C, which may reduce the amount of processing performed by the wireless communication device 102C for motion sensing. The header may include additional information, such as an indication of whether another device in the communication system 100 has detected motion, an indication of the modulation type, an identification of the device transmitting the signal, etc.

[0222] exist Figure 1In the illustrated example, the wireless communication system 100 is a wireless mesh network having a wireless communication link between each of the wireless communication devices 102. In the illustrated example, the wireless communication link between the wireless communication device 102C and the wireless communication device 102A can be used to detect the motion detection field 110A, the wireless communication link between the wireless communication device 102C and the wireless communication device 102B can be used to detect the motion detection field 110B, and the wireless communication link between the wireless communication device 102A and the wireless communication device 102B can be used to detect the motion detection field 110C. In some cases, each wireless communication device 102 detects motion in the motion detection field 110 accessed by the device by processing a received signal that is based on a wireless signal transmitted by the wireless communication device 102 through the motion detection field 110. For example, when Figure 1 As the person 106 is shown moving in the motion detection field 110A and the motion detection field 110C, the wireless communication device 102 may detect motion based on signals it receives based on wireless signals transmitted through the corresponding motion detection field 110. For example, the wireless communication device 102A may detect motion of the person 106 in the motion detection fields 110A, 110C, the wireless communication device 102B may detect motion of the person 106 in the motion detection field 110C, and the wireless communication device 102C may detect motion of the person 106 in the motion detection field 110A.

[0223] In some cases, motion detection field 110 may include, for example, air, a solid material, a liquid, or another medium through which wireless electromagnetic signals may propagate. Figure 1 In the example shown, motion detection field 110A provides a wireless communication channel between wireless communication device 102A and wireless communication device 102C, motion detection field 110B provides a wireless communication channel between wireless communication device 102B and wireless communication device 102C, and motion detection field 110C provides a wireless communication channel between wireless communication device 102A and wireless communication device 102B. In some aspects of operation, wireless signals transmitted on a wireless communication channel (separate or shared with a wireless communication channel used for network traffic) are used to detect movement of objects in space. The objects can be any type of static or movable object, and can be animate or inanimate. For example, the object can be a person (e.g., Figure 1The motion information from the wireless communication device may be analyzed to determine the location of the detected motion. For example, as further described below, one of the wireless communication devices 102 (or another device communicatively coupled to the wireless communication device 102) may determine that the detected motion is located near a particular wireless communication device.

[0224] Figure 2A and Figure 2B is a diagram showing example wireless signals transmitted between wireless communication devices 204A, 204B, 204C. The wireless communication devices 204A, 204B, 204C may be, for example Figure 1 The wireless communication devices 102A, 102B, 102C or other types of wireless communication devices are shown. The wireless communication devices 204A, 204B, 204C transmit wireless signals through the space 200. The space 200 can be completely or partially closed or open at one or more boundaries. In an example, the space 200 can be a sensing space. The space 200 can be or can include the interior of a room, multiple rooms, a building, an indoor area, an outdoor area, etc. In the example shown, the first wall 202A, the second wall 202B and the third wall 202C at least partially enclose the space 200.

[0225] exist Figure 2A and Figure 2B In the example shown, the wireless communication device 204A may be configured to repeatedly (e.g., periodically, intermittently, at predetermined intervals, non-predetermined intervals, or random intervals, etc.) transmit wireless signals. The wireless communication devices 204B and 204C may be configured to receive signals based on the signals transmitted by the wireless communication device 204A. The wireless communication devices 204B and 204C may each have a modem (e.g., Figure 1 ), which is configured to process received signals to detect movement of objects in the space 200.

[0226] As shown in the figure, the object is located Figure 2A The first position 214A in the Figure 2B The second positioning 214B in Figure 2A and Figure 2B In the figure, the moving object in the space 200 is represented as a person, but the moving object may be another type of object. For example, the moving object may be an animal, an inorganic object (e.g., a system, a device, a device, or an assembly), an object that defines all or part of the boundaries of the space 200 (e.g., a wall, a door, a window, etc.), or another type of object.

[0227] like Figure 2A and Figure 2B 2, multiple example paths of wireless signals transmitted from the wireless communication device 204A are illustrated by dashed lines. Along a first signal path 216, a wireless signal is transmitted from the wireless communication device 204A and reflected from the first wall 202A toward the wireless communication device 204B. Along a second signal path 218, a wireless signal is transmitted from the wireless communication device 204A and reflected from the second wall 202B and the first wall 202A toward the wireless communication device 204C. Along a third signal path 220, a wireless signal is transmitted from the wireless communication device 204A and reflected from the second wall 202B toward the wireless communication device 204C. Along a fourth signal path 222, a wireless signal is transmitted from the wireless communication device 204A and reflected from the third wall 202C toward the wireless communication device 204B.

[0228] exist Figure 2A In FIG. 2 , along fifth signal path 224A, a wireless signal is transmitted from wireless communication device 204A and reflected from an object at first location 214A toward wireless communication device 204C. Figure 2A and Figure 2B During the time period, the surface of the object moves from the first location 214A to the second location 214B (e.g., a certain distance from the first location 214A) in the space 200. Figure 2B In the sixth signal path 224B, the wireless signal is transmitted from the wireless communication device 204A and reflected from the object at the second location 214B toward the wireless communication device 204C. As the object moves from the first location 214A to the second location 214B, Figure 2B The sixth signal path 224B depicted in FIG. Figure 2A . In some instances, signal paths may be added, removed, or otherwise modified due to movement of objects in space.

[0229] Figure 2A and Figure 2B The example wireless signal shown may experience attenuation, frequency shift, phase shift, or other effects through its respective path, and may have a portion propagating in another direction, for example, through the first wall 202A, the second wall 202B, and the third wall 202C. In some examples, the wireless signal is a radio frequency (RF) signal. The wireless signal may include other types of signals.

[0230] exist Figure 2A and Figure 2B In the example shown, the wireless communication device 204A can repeatedly transmit wireless signals. Specifically, Figure 2A shows a wireless signal transmitted from the wireless communication device 204A at a first time, and Figure 2BThe same wireless signal is shown transmitted from the wireless communication device 204A at a second later time. The transmitted signal may be transmitted continuously, periodically, at random or intermittent times, etc., or a combination thereof. The transmitted signal may have multiple frequency components in a frequency bandwidth. The transmitted signal may be transmitted from the wireless communication device 204A in an omnidirectional manner, a directional manner, or in other ways. In the example shown, the wireless signal traverses multiple corresponding paths in the space 200, and the signal along each path may be attenuated due to path loss, scattering, reflection, etc. and may have a phase or frequency offset.

[0231] like Figure 2A and Figure 2B As shown, the signals from the first to sixth paths 216, 218, 220, 222, 224A and 224B are combined at the wireless communication device 204C and the wireless communication device 204B to form the received signal. Due to the influence of multiple paths in the space 200 on the transmitted signal, the space 200 can be represented as a transfer function (e.g., a filter) in which the transmitted signal is input and the received signal is output. When an object moves in the space 200, the attenuation or phase shift affecting the signal in the signal path may change, and therefore, the transfer function of the space 200 may change. Assuming that the same wireless signal is transmitted from the wireless communication device 204A, if the transfer function of the space 200 changes, the output of the transfer function - the received signal - will also change. The change in the received signal can be used to detect the movement of the object.

[0232] Mathematically, the transmitted signal f(t) transmitted from the first wireless communication device 204A can be described according to equation (1):

[0233]

[0234] where ω n represents the frequency of the nth frequency component of the transmitted signal, c n represents the complex coefficient of the nth frequency component, and t represents time. In the case where f(t) is transmitted from the first wireless communication device 204A, the output signal r from the path k is k (t) can be described according to equation (2):

[0235]

[0236] where α n,k represents the attenuation factor (or channel response; e.g., due to scattering, reflection, and path loss) of the nth frequency component along k, and φ n,krepresents the phase of the signal along the nth frequency component of k. Then, the received signal R at the wireless communication device can be described as the sum of all output signals R from all paths to the wireless communication device, which is shown in equation (3):

[0237] R=∑ k r k (t)…(3)

[0238] Substituting equation (2) into equation (3) yields the following equation (4):

[0239]

[0240] R at the wireless communication device can then be analyzed. For example, R at the wireless communication device can be transformed to the frequency domain using a fast Fourier transform (FFT) or another type of algorithm. The transformed signal can represent R as a series of R complex values, with each frequency component in the corresponding frequency components having a complex value (at R frequencies R). For frequency ω n The frequency component at , complex value ω n It can be expressed as the following equation (5):

[0241]

[0242] For a given ω n , H n Instructions n The relative amplitude and phase shift of the received signal at the location. When the object moves in space, H n Due to the spatial variation of H n Therefore, the changes detected in the channel response can indicate the movement of objects in the communication channel. In some cases, noise, interference or other phenomena may affect the channel response detected by the receiver, and the motion detection system can reduce or isolate these effects to improve the accuracy and quality of the motion detection capability. In some embodiments, the overall channel response can be expressed as follows Equation (6):

[0243]

[0244] In some cases, the spatial channel response h can be determined, for example, based on the mathematical theory of the estimate ch For example, the candidate R "# To modify the reference signal R "# , and then the maximum likelihood method can be used to select the signal that matches the received signal (R "# ) is the best matching candidate channel. In some cases, With candidate The estimated received signal is obtained by convolution And then change The channel coefficients are The square error of is minimized. This can be mathematically described as follows:

[0245]

[0246] The optimization criterion is shown in equation (8):

[0247]

[0248] The minimization or optimization process can utilize adaptive filtering techniques such as least mean square (LMS), recursive least squares (RLS), batch least squares (BLS), etc. The channel response can be a finite impulse response (FIR) filter, an infinite impulse response (IIR) filter, etc. As shown in the above equation, the received signal can be considered as the convolution of the reference signal and the channel response. The convolution operation means that the channel coefficients have a certain degree of correlation with each delayed copy of the delayed copy of the reference signal. Therefore, the convolution operation shown in the above equation indicates that the received signal appears at different delay points, and each delayed copy is weighted by the channel coefficient.

[0249] Figure 3A and Figure 3B It shows that according to Figure 2A and Figure 2B Graphs of examples of channel responses 360, 370 calculated for wireless signals transmitted between wireless communication devices 204A, 204B, 204C in FIG. Figure 3A and Figure 3B Also shown is a frequency domain representation 350 of the initial wireless signal transmitted by the wireless communication device 204A. In the example shown, Figure 3A The channel response 360 ​​in represents the signal received by the wireless communication device 204B when there is no motion in the space 200, and Figure 3B The channel response 370 in FIG. 2 represents the channel response 370 after the object moves in the space 200. Figure 2B The signal received by the wireless communication device 204B in.

[0250] exist Figure 3A and Figure 3B In the example shown, for purposes of illustration, wireless communication device 204A transmits a signal having a flat frequency distribution (the amplitude of each frequency component f3, f1, and f4 is the same), as shown in frequency domain representation 350. Due to the interaction of the signal with space 200 (and objects therein), the signal received at wireless communication device 204B based on the signal sent from wireless communication device 204 is different from the transmitted signal. In this example, the received signal represents the channel response of space 200 where the transmitted signal had a flat frequency distribution. Figure 3A and Figure 3B As shown, the channel responses 360, 370 are different from the frequency domain representation 350 of the transmitted signal. When motion occurs in the space 200, the channel response will also change. For example, Figure 3B As shown, channel response 370 associated with motion of an object in space 200 is different from channel response 360 ​​associated with no motion in space 200 .

[0251] In addition, when an object moves within space 200, the channel response may be different from channel response 370. In some cases, space 200 may be divided into unique regions, and the channel responses associated with each region may share one or more characteristics (e.g., shape), as described below. Thus, the motion of an object within different unique regions may be distinguished, and the location of the detected motion may be determined based on analysis of the channel response.

[0252] Figure 4A and Figure 4B 401, 403 are diagrams showing example channel responses 401, 403 associated with motion of an object 406 in distinct regions 408, 412 of a space 400. In the example shown, the space 400 is a building, and the space 400 is divided into a plurality of distinct regions: a first region 408, a second region 410, a third region 412, a fourth region 414, and a fifth region 416. In some cases, the space 400 may contain additional or fewer regions. Figure 4A and Figure 4B As shown, the regions within space 400 may be defined by walls between rooms. Additionally, the regions may be defined by ceilings between floors of a building. For example, space 400 may include additional floors with additional rooms. Additionally, in some cases, the multiple regions of the space may be or include multiple floors in a multi-story building, multiple rooms in a building, or multiple rooms on a particular floor of a building. Figure 4A In the illustrated example, although the object positioned in the first area 408 is represented as a person 406, the moving object may be another type of object, such as an animal or an inorganic object.

[0253] In the example shown, wireless communication device 402A is positioned in fourth region 414 of space 400, wireless communication device 402B is positioned in second region 410 of space 400, and wireless communication device 402C is positioned in fifth region 416 of space 400. Wireless communication devices 402 may be positioned in a manner similar to that of FIG. Figure 1The wireless communication device 402 may operate in the same or similar manner as the wireless communication device 102 of the space 400. For example, the wireless communication device 402 may be configured to transmit and receive wireless signals, and detect whether motion has occurred in the space 400 based on the received signals. For example, the wireless communication device 402 may periodically or repeatedly transmit a motion detection signal through the space 400, and receive a signal based on the motion detection signal. The wireless communication device 402 may analyze the received signals to detect whether the object has moved in the space 400, for example, by analyzing a channel response associated with the space 400 based on the received signals. In addition, in some embodiments, the wireless communication device 402 may analyze the received signals to identify the location of the detected motion within the space 400. For example, the wireless communication device 402 may analyze the characteristics of the channel response to determine whether the channel response shares the same or similar characteristics with the channel responses known to be associated with the first to fifth regions 408, 410, 412, 414, 416 of the space 400.

[0254] In the example shown, one (or more) of the wireless communication devices 402 repeatedly transmits a motion detection signal (e.g., a reference signal) through the space 400. In some cases, the motion detection signal may have a flat frequency distribution, where the amplitudes of f3, f1, and f4 are the same or nearly the same. For example, the motion detection signal may have a frequency distribution similar to Figure 3A and Figure 3B The frequency domain shown represents the frequency response of 350. In some cases, the motion detection signal may have a different frequency distribution. Due to the interaction of the reference signal with the space 400 (and the objects therein), the signal received at the other wireless communication device 402 based on the motion detection signal transmitted from the other wireless communication device 402 is different from the transmitted reference signal.

[0255] Based on the received signals, wireless communication device 402 can determine a channel response for space 400. When motion occurs in a unique region within the space, unique characteristics can be seen in the channel response. For example, while the channel response may be slightly different for motion within the same region of space 400, the channel responses associated with motion in the unique region can generally share the same shape or other characteristics. For example, Figure 4A The channel response 401 represents an example channel response associated with the motion of the object 406 in the first region 408 of the space 400, while Figure 4B The channel response 403 of φ represents an example channel response associated with the motion of the object 406 in the third region 412 of the space 400. The channel responses 401, 403 are associated with signals received by the same wireless communication device 402 in the space 400.

[0256] Figure 4C and Figure 4D It shows Figure 4A and Figure 4B 400. A plot of channel responses 401, 403 of a signal transmitted over a channel response 460 associated with no motion occurring in space 400 is shown. In the example shown, wireless communication device 402 transmits a motion detection signal having a flat frequency distribution, as shown in frequency domain representation 450. When motion occurs in space 400, a change in the channel response will occur relative to channel response 460 associated with no motion, and thus, motion of objects in space 400 can be detected by analyzing the change in the channel response. Additionally, the relative location of the detected motion within space 400 can be identified. For example, the shape of the channel response associated with the motion can be compared to reference information (e.g., using a trained artificial intelligence (AI) model) to classify the motion as having occurred within a unique region of space 400.

[0257] When there is no motion in the space 400 (e.g., when the object 406 is not present), the wireless communication device 402 can calculate a channel response 460 associated with no motion. The channel response may vary slightly due to a variety of factors; however, multiple channel responses 460 associated with different time periods may share one or more characteristics. In the example shown, the channel response 460 associated with no motion has a decreasing frequency distribution (the amplitude of each of f3, f1, and f4 is less than the previous one). In some cases (e.g., based on different room layouts or placement of the wireless communication device 402), the distribution of the channel response 460 may be different.

[0258] When motion occurs in space 400, the channel response will change. For example, Figure 4C and Figure 4D In the example shown, the channel response 401 associated with the motion of the object 406 in the first area 408 is different from the channel response 460 associated with no motion, and the channel response 403 associated with the motion of the object 406 in the third area 412 is different from the channel response 460 associated with no motion. The channel response 401 has a concave parabolic frequency distribution (the amplitude of the intermediate frequency component f1 is smaller than the external frequency components f1 and f3), while the channel response 403 has a convex asymptotic frequency distribution (the amplitude of the intermediate frequency component f2 is larger than the external frequency components f3 and f4). In some cases (e.g., based on different room layouts or placement of the wireless communication device 402), the distributions of the channel responses 401, 403 may be different.

[0259] Analyzing the channel response can be considered similar to analyzing a digital filter. The channel response can be formed by reflections of objects in space and by reflections generated by moving or stationary people. When a reflector (e.g., a person) moves, it changes the channel response. This may translate into changes in the equivalent taps of a digital filter, which can be considered to have poles and zeros (poles amplify the frequency components of the channel response and appear as peaks or highs in the response, while zeros attenuate the frequency components of the channel response and appear as troughs, lows, or zeros in the response). The changing digital filter can be characterized by the location of its peaks and troughs, and the channel response can be similarly characterized by its peaks and troughs. For example, in some embodiments, motion can be detected by analyzing the zeros and peaks in the frequency components of the channel response (e.g., by marking their location on the frequency axis and their amplitude).

[0260] In some embodiments, motion can be detected using time series aggregation. Time series aggregation can be performed by observing the characteristics of the channel response on a moving window and by aggregating the results of windowing using statistical metrics (e.g., mean, variance, principal component, etc.). During an instance of motion, due to the continuous change of the scattering scene, a typical digital filter feature will be displaced in position and flipped between some values. That is, the equivalent digital filter exhibits a range of values ​​for its peak and zero values ​​(due to motion). By looking at this range of values, a unique profile can be identified for a unique region in space (in an example, a profile can also be referred to as a signature).

[0261] In some embodiments, an AI model can be used to process data. AI models can be of various types, such as linear regression models, logistic regression models, linear discriminant analysis models, decision tree models, naive Bayes models, K nearest neighbor models, learning vector quantization models, support vector machines, bagging and random forest models, and deep neural networks. In general, all AI models are designed to learn functions that provide the most accurate correlation between input values ​​and output values, and are trained using historical input and output sets that are known to be relevant. In an example, artificial intelligence can also be referred to as machine learning.

[0262] In some embodiments, the distribution of channel responses associated with motion in unique regions of space 400 may be learned. For example, machine learning may be used to classify channel response characteristics where object motion is located within unique regions of space. In some cases, a user associated with wireless communication device 402 (e.g., an owner or other occupant of space 400) may assist in the learning process. For example, referring to Figure 4A and Figure 4BIn the example shown, the user can move in each of the first through fifth regions 408, 410, 412, 414, 416 during the learning phase and can indicate (e.g., via a user interface on the mobile computing device) that he / she is moving in one of the particular regions in the space 400. For example, when the user moves through the first region 408 (e.g., Figure 4A ), a user may indicate on a mobile computing device that he / she is located in a first area 408 (and the area may be named "bedroom," "living room," "kitchen," or another type of room of a building, as appropriate). As the user moves through the area, a channel response may be obtained and the channel response may be "tagged" with the location (area) indicated by the user. The user may repeat the same process for other areas of space 400. The term "tagging," as used herein, may refer to marking and identifying a channel response with a location indicated by the user or any other information.

[0263] The labeled channel responses can then be processed (e.g., by machine learning software) to identify unique characteristics of the channel responses associated with motion in a unique area. Once identified, the identified unique characteristics can be used to determine the location of the detected motion for the newly calculated channel response. For example, the labeled channel responses can be used to train the AI ​​model, and once trained, the newly calculated channel response can be input to the AI ​​model, and the AI ​​model can output the location of the detected motion. For example, in some cases, the average, range, and absolute value are input to the AI ​​model. In some cases, the amplitude and phase of the complex channel response itself can also be input. These values ​​allow the AI ​​model to design arbitrary front-end filters to select the features most relevant to making accurate predictions of motion in a unique area of ​​space. In some embodiments, the AI ​​model is trained by performing stochastic gradient descent. For example, the most active channel response changes during a certain area can be monitored during training, and specific channel changes can be heavily weighted (by training and adjusting the weights in the first layer to be related to those shapes, trends, etc.). Weighted channel changes can be used to create a measure that is activated when a user appears in a certain area.

[0264] For the extracted features, such as channel response zeros and peaks, a time series (of zeros / peaks) can be created using aggregation within a moving window, taking snapshots of a few features in the past and present, and using the aggregated values ​​as input to the network. Thus, the network will try to aggregate the values ​​in a certain area while adjusting its weights to cluster the values, which can be done by creating a decision surface based on a logistic classifier. The decision surface divides different clusters, and subsequent layers can form categories based on a single cluster or a combination of clusters.

[0265] In some embodiments, the AI ​​model includes two or more layers of inference. The first layer is used as a logical classifier, which can divide values ​​of different concentrations into separate clusters, and the second layer combines some of these clusters together to create categories for unique regions. In addition, subsequent layers can help expand unique regions to clusters of more than two categories. For example, a fully connected AI model may include an input layer corresponding to the number of features tracked, an intermediate layer corresponding to the number of valid clusters (by iterating between selections), and a final layer corresponding to different regions. In the case where the complete channel response information is input to the AI ​​model, the first layer can be used as a shape filter that can correlate certain shapes. Therefore, the first layer can be locked to a certain shape, the second layer can generate a measure of the changes that occur in those shapes, and the third and subsequent layers can create a combination of those changes and map the changes to different regions in space. The outputs of different layers can then be combined by a fusion layer.

[0266] B. Wi-Fi Sensing System Example Method and Apparatus

[0267] Section B describes systems and methods useful for a wireless sensing system configured to send sensing transmissions and make sensing measurements.

[0268] Figure 5 Some architectural implementations of an implementation of a system 500 for Wi-Fi sensing in accordance with some embodiments are depicted.

[0269] The system 500 may include a plurality of networked devices including a plurality of sensing-capable devices and a plurality of access points. In one example, the system 500 may include a plurality of sensing receivers 502-(1-M), a plurality of sensing transmitters 504-(1-N), a remote processing device 506, and a network 560 that enables communication between system components for information exchange. In one example, any of the sensing receivers 502-(1-M) or any of the sensing transmitters 504-(1-N) may be a sensing-capable device. The system 500 may be an example or instance of the wireless communication system 100, and the network 560 may be an example or instance of a wireless network or a cellular network, details of which are described in detail in detail in the accompanying drawings. Figure 1 and the accompanying description.

[0270] According to an embodiment, the plurality of sensing receivers 502-(1-M) may be configured to receive one or more sensing transmissions (e.g., from one or more sensing transmitters of the plurality of sensing transmitters 504-(1-N)) and perform one or more measurements useful for Wi-Fi sensing (e.g., channel representation information (CRI) measurements, such as channel state information (CSI) or time domain channel representation information (TD-CRI)). In an example, these measurements may be referred to as sensing measurements. The sensing measurements may be processed to achieve the sensing objectives of the system 500. In an embodiment, one or more sensing receivers of the plurality of sensing receivers 502-(1-M) may be an AP. In some embodiments, one or more sensing receivers of the plurality of sensing receivers 502-(1-M) may be a non-AP STA. In some embodiments, one or more sensing receivers of the plurality of sensing receivers 502-(1-M) may function as a sensing initiator and / or a sensing responder.

[0271] According to one embodiment, one or more of the plurality of sensing receivers 502-(1-M) may be provided by: Figure 1 In some embodiments, one or more of the plurality of sensing receivers 502-(1-M) may be implemented by a wireless communication device 102 or the like. Figure 2A and Figure 2B In addition, one or more of the plurality of sensing receivers 502-(1-M) may be implemented by a wireless communication device 204 or the like. Figure 4A and Figure 4BThe system 500 may be implemented by a device such as the wireless communication device 402 shown. In one embodiment, one or more sensing receivers among the plurality of sensing receivers 502-(1-M) may coordinate and control the communication between the plurality of sensing transmitters 504-(1-N). According to one embodiment, one or more sensing receivers among the plurality of sensing receivers 502-(1-M) may be enabled to control a sensing measurement session including one or more sensing measurement instances to ensure that the required sensing transmission is performed at the required time and to ensure accurate determination of one or more sensing measurement results. In some embodiments, one or more sensing receivers among the plurality of sensing receivers 502-(1-M) may process the sensing measurement results to achieve the sensing objectives of the system 500. In one embodiment, one or more sensing receivers among the plurality of sensing receivers 502-(1-M) may be STAs. In one embodiment, one or more sensing receivers among the plurality of sensing receivers 502-(1-M) may be APs. In some embodiments, one or more sensing receivers of the plurality of sensing receivers 502 -( 1 -M) may be configured to transmit sensing measurements to a remote processing device 506 , and the remote processing device 506 may be configured to process the sensing measurements to achieve sensing objectives of the system 500 .

[0272] Reference again Figure 5 In some embodiments, one or more of the plurality of sensing transmitters 504-(1-N) may be configured to send one or more sensing transmissions to one or more of the plurality of sensing receivers 502-(1-M), based on which one or more sensing measurements may be performed for Wi-Fi sensing. In one embodiment, one or more of the plurality of sensing transmitters 504-(1-N) may be STAs. In one embodiment, one or more of the plurality of sensing transmitters 504-(1-N) may be APs. In some embodiments, one or more of the plurality of sensing transmitters 504-(1-N) may function as sensing initiators and / or sensing responders.

[0273] According to one embodiment, one or more of the plurality of sensing transmitters 504-(1-N) may be provided by: Figure 1 In some embodiments, one or more of the plurality of sensing transmitters 504-(1-M) may be implemented by a wireless communication device 102 as shown. Figure 2A and Figure 2B In addition, one or more of the plurality of sensing transmitters 504-(1-M) may be implemented by a wireless communication device 204 or the like. Figure 4A and Figure 4BIn some embodiments, the communication between one or more sensing receivers in the plurality of sensing receivers 502-(1-M) and one or more sensing transmitters in the plurality of sensing transmitters 504-(1-N) may be performed via a station management entity (SME) and a MAC layer management entity (MLME) protocol.

[0274] In some embodiments, the remote processing device 506 may be configured to receive sensing measurements from one or more of the plurality of sensing receivers 502-(1-M) and process the sensing measurements. In one example, the remote processing device 506 may process and analyze the sensing measurements to identify one or more features of interest. According to some embodiments, the remote processing device 506 may include / execute a sensing algorithm. In one embodiment, the remote processing device 506 may be a STA. In some embodiments, the remote processing device 506 may be an AP. According to one embodiment, the remote processing device 506 may be a processor such as a processor. Figure 1 In some embodiments, the remote processing device 506 may be implemented by a device such as the wireless communication device 102 shown in FIG. Figure 2A and Figure 2B The remote processing device 506 may be implemented by a wireless communication device 204 or the like as shown in FIG. Figure 4A and Figure 4B The remote processing device 506 may be implemented by a device such as the wireless communication device 402 shown in FIG. In some embodiments, the remote processing device 506 may be any computing device, such as a desktop computer, a laptop computer, a tablet computer, a mobile device, a personal digital assistant (PDA), or any other computing device. In an embodiment, the remote processing device 506 may function as a sensing initiator, where a sensing algorithm determines a Wi-Fi sensing session and sensing measurement results required to complete the measurement activity. In an example, the remote processing device 506 may transmit sensing measurement parameters and / or transmission parameters required to initiate a Wi-Fi sensing session to one or more sensing receivers of the plurality of sensing receivers 502-(1-M) and / or one or more sensing transmitters of the plurality of sensing transmitters 504-(1-N) to coordinate and control sensing transmissions for performing sensing measurements.

[0275] For more details, refer to Figure 5 , the sensing receiver 502-1 (which is an example of one or more sensing receivers in the plurality of sensing receivers 502-(1-M)) may include a processor 508-1 and a memory 510-1. For example, the processor 508-1 and the memory 510-1 of the sensing receiver 502-1 may be respectively as follows: Figure 1The processor 114 and memory 116 shown. In one embodiment, the sensing receiver 502-1 may further include a transmitting antenna 512-1, a receiving antenna 514-1, and a sensing agent 516-1. In some embodiments, the antenna may be used to transmit and receive signals in a half-duplex format. When the antenna is transmitting, the antenna may be referred to as a transmitting antenna 512-1, and when the antenna is receiving, the antenna may be referred to as a receiving antenna 514-1. It should be understood by those of ordinary skill in the art that the same antenna may be a transmitting antenna 512-1 in some cases and a receiving antenna 514-1 in other cases. In the case of an antenna array, one or more antenna elements may be used to transmit or receive signals, for example, in a beamforming environment. In some instances, a group of antenna elements for transmitting a composite signal may be referred to as a transmitting antenna 512-1, and a group of antenna elements for receiving a composite signal may be referred to as a receiving antenna 514-1. In some examples, each antenna is equipped with its own transmit and receive paths that can be alternately switched to connect to the antenna depending on whether the antenna is operating as a transmit antenna 512-1 or a receive antenna 514-1.

[0276] In one embodiment, the sensing agent 516-1 may be responsible for causing the sensing receiver 502-1 to receive the sensing transmission and the associated sensing measurement parameters and / or transmission parameters to calculate the sensing measurement results. In an example, the sensing agent 516-1 may be responsible for processing the sensing measurement results to achieve the sensing goal. In some embodiments, receiving the sensing transmission and optionally associated sensing measurement parameters and / or transmission parameters and calculating the sensing measurement results may be performed by the sensing agent 516-1 running in the medium access control (MAC) layer of the sensing receiver 502-1, and processing the sensing measurement results to achieve the sensing goal may be performed by an algorithm (e.g., sensing algorithm 518-1) running in the application layer of the sensing receiver 502-1. In an example, the sensing algorithm 518-1 running in the application layer of the sensing receiver 502-1 may be referred to as a Wi-Fi sensing agent, a sensing application, or a sensing algorithm. In an example, the sensing algorithm 518-1 may include and / or execute the sensing agent 516-1. According to some embodiments, the sensing agent 516-1 may include and / or execute a sensing algorithm 518-1. In some embodiments, the sensing agent 516-1 running in the MAC layer of the sensing receiver 502-1 and the sensing algorithm 518-1 running in the application layer of the sensing receiver 502-1 may run separately on the processor 508-1. In one embodiment, the sensing agent 516-1 may pass one or more of the sensing measurement parameters, transmission parameters, or physical layer parameters (e.g., such as channel representation information, examples of which are CSI and TD-CRI) between the MAC layer of the sensing receiver 502-1 and the application layer of the sensing receiver 502-1. In one example, the sensing agent 516-1 in the MAC layer or the sensing algorithm 518-1 in the application layer may operate on the physical layer parameters, for example, to detect one or more features of interest. In an example, the sensing algorithm 518-1 may form a service or feature that can be presented to an end user. According to one embodiment, the communication between the MAC layer of the sensing receiver 502-1 and other layers or components (including the application layer) of the sensing receiver 502-1 can be based on communication interfaces such as MLME interfaces and data interfaces. In an example, the sensing agent 516-1 can be configured to determine the number and timing of sensing transmissions and sensing measurements for the purpose of Wi-Fi sensing. In some embodiments, the sensing agent 516-1 can be configured to transmit the sensing measurement results to multiple sensing transmitters 504-(1-N) and / or remote processing devices 506 for further processing. In one embodiment, the sensing agent 516-1 can be configured to cause at least one of the transmitting antennas 512-1 to send a message to one or more sensing transmitters or remote processing devices 506 in the multiple sensing transmitters 504-(1-N).In addition, the sensing agent 516-1 can be configured to receive messages from one or more of the plurality of sensing transmitters 504-(1-N) or the remote processing device 506 via at least one of the receiving antennas 514-1. In one example, the sensing agent 516-1 can be configured to perform sensing measurements based on sensing transmissions received from one or more of the plurality of sensing transmitters 504-(1-N).

[0277] In some embodiments, the sensing receiver 502-1 may include a sensing measurement storage device 520-1. In one embodiment, the sensing measurement storage device 520-1 may store sensing measurement results calculated by the sensing receiver 502-1 based on the received sensing transmission. In one example, the sensing measurement results stored in the sensing measurement storage device 520-1 may be updated periodically or dynamically as needed. In some embodiments, the sensing receiver 502-1 may include a sensing measurement parameter storage device 522-1. In one embodiment, the sensing measurement parameter storage device 522-1 may store sensing measurement parameters and / or transmission parameters applicable to one or more sensing measurement establishments. In one embodiment, the sensing measurement parameter storage device 522-1 may store sensing measurement parameters and / or transmission parameters applicable to one or more sensing measurement sessions. In one embodiment, the sensing measurement parameter storage device 522-1 may store sensing measurement parameters and / or transmission parameters applicable to one or more sensing measurement instances. In one example, the sensing measurement parameters and / or transmission parameters stored in the sensing measurement parameter storage device 522-1 may be updated periodically or dynamically as needed. In one embodiment, the sensory measurement storage device 520 - 1 and the sensory measurement parameter storage device 522 - 1 may include any type or form of storage device, such as a database or a file system, or be coupled to the memory 510 - 1 .

[0278] Reference again Figure 5 , the sensing transmitter 504-1 (which is an example of one or more sensing transmitters in the plurality of sensing transmitters 504-(1-N)) may include a processor 528-1 and a memory 530-1. For example, the processor 528-1 and the memory 530-1 of the sensing transmitter 504-1 may be, respectively, Figure 1 The processor 114 and the memory 116 are shown. In one embodiment, the sensing transmitter 504-1 may further include a transmitting antenna 532-1, a receiving antenna 534-1, and a sensing agent 536-1.

[0279] The sensing agent 536-1 can be configured to cause at least one of the transmitting antennas 532-1 and at least one of the receiving antennas 534-1 to exchange messages with one or more of the sensing receivers 502-(1-M) or the remote processing device 506. In some embodiments, the antenna can be used to transmit and receive in a half-duplex format. When the antenna is transmitting, the antenna can be referred to as a transmitting antenna 532-1, and when the antenna is receiving, the antenna can be referred to as a receiving antenna 534-1. It should be understood by those of ordinary skill in the art that the same antenna can be a transmitting antenna 532-1 in some cases and a receiving antenna 534-1 in other cases. In the case of an antenna array, one or more antenna elements can be used to transmit or receive signals, for example, in a beamforming environment. In some instances, a group of antenna elements for transmitting a composite signal can be referred to as a transmitting antenna 532-1, and a group of antenna elements for receiving a composite signal can be referred to as a receiving antenna 534-1. In some examples, each antenna is equipped with its own transmit and receive paths, which can be alternately switched to connect to the antenna depending on whether the antenna is operating as a transmit antenna 532-1 or a receive antenna 534-1.

[0280] In one embodiment, the sensing agent 536-1 can be responsible for causing the sensing transmitter 504-1 to send a sensing transmission, and in an example, receiving associated sensing measurements from one or more sensing receivers of the plurality of sensing receivers 502-(1-M). In an example, the sensing agent 536-1 can be responsible for processing the sensing measurements to achieve the sensing goal. In some embodiments, the sensing agent 536-1 can run in the medium access control (MAC) layer of the sensing transmitter 504-1, and processing the sensing measurements to achieve the sensing goal can be performed by a sensing algorithm 538-1, which can run in an application layer in the sensing transmitter 504-1 in an example. In an example, the sensing algorithm 538-1 running in the application layer of the sensing transmitter 504-1 is referred to as a Wi-Fi sensing agent, a sensing application, or a sensing algorithm. In an example, the sensing algorithm 538-1 can include and / or execute the sensing agent 536-1. According to some embodiments, the sensing agent 536-1 can include and / or execute the sensing algorithm 538-1. In some embodiments, the sensing agent 536-1 may run in the MAC layer of the sensing transmitter 504-1, and the sensing algorithm 538-1 may run in the application layer of the sensing transmitter 504-1. In some embodiments, the sensing agent 536-1 and the sensing algorithm 538-1 of the sensing transmitter 504-1 may run separately on the processor 528-1. In one embodiment, the sensing agent 536-1 may pass sensing measurement parameters, transmission parameters, or physical layer parameters between the MAC layer of the sensing transmitter 504-1 and the application layer of the sensing transmitter 504-1. In one example, the sensing agent 536-1 in the MAC layer or the sensing algorithm 538-1 in the application layer may control physical layer parameters, such as physical layer parameters for generating one or more sensing transmissions. In an example, the sensing algorithm 538-1 may form a service or feature that may be presented to an end user. According to one embodiment, the communication between the MAC layer of the sensing transmitter 504-1 and other layers or components (including the application layer) of the sensing transmitter 504-1 can be based on communication interfaces such as MLME interfaces and data interfaces. In an example, the sensing agent 536-1 can be configured to determine the number and timing of sensing transmissions for the purpose of Wi-Fi sensing. In some embodiments, the sensing agent 536-1 can be configured to cause the sensing transmitter 504-1 to send the sensing transmission to one or more sensing receivers in the plurality of sensing receivers 502-(1-M). In one embodiment, the sensing agent 536-1 can be configured to cause at least one transmitting antenna in the transmitting antenna 532-1 to send a message to one or more sensing receivers in the plurality of sensing receivers 502-(1-M) or the remote processing device 506.Additionally, the sensing agent 536 - 1 may be configured to receive messages from one or more of the plurality of sensing receivers 502 -( 1 -M) or the remote processing device 506 via at least one of the receiving antennas 534 - 1 .

[0281] In some embodiments, the sensing transmitter 504-1 may include a sensing measurement storage device 540-1. In one embodiment, the sensing measurement storage device 540-1 may store sensing measurement results calculated by one or more sensing receivers of the plurality of sensing receivers 502-(1-M) based on sensing transmissions sent by the sensing transmitter 504-1 and sent to the sensing transmitter 504-1 by one or more sensing receivers of the plurality of sensing receivers 502-(1-M). In one example, the sensing measurement results stored in the sensing measurement storage device 540-1 may be updated periodically or dynamically as needed. In one embodiment, the sensing measurement storage device 540-1 may include any type or form of storage device, such as a database or file system, or be coupled to the memory 530-1.

[0282] In some embodiments, the sensing transmitter 504-1 may include a sensing measurement parameter storage device 542-1. In one embodiment, the sensing measurement parameter storage device 542-1 may store sensing measurement parameters and / or transmission parameters applicable to one or more sensing measurement sessions. In one embodiment, the sensing measurement parameter storage device 542-1 may store sensing measurement parameters and / or transmission parameters applicable to one or more sensing measurement establishments. In one embodiment, the sensing measurement parameter storage device 542-1 may store sensing measurement parameters and / or transmission parameters applicable to one or more sensing measurement instances. In one instance, the sensing measurement parameters and / or transmission parameters stored in the sensing measurement parameter storage device 542-1 may be periodically or dynamically updated as needed. In one embodiment, the sensing measurement storage device 540-1 and the sensing measurement parameter storage device 542-1 may include any type or form of storage device, such as a database or file system, or be coupled to the memory 530-1.

[0283] For more details, refer to Figure 5 , the remote processing device 506 may include a processor 548 and a memory 550. For example, the processor 548 and the memory 550 of the remote processing device 506 may be respectively Figure 1The processor 114 and memory 116 shown. In one embodiment, the remote processing device 506 may further include a transmitting antenna 552, a receiving antenna 554, a sensing agent 556, and a sensing algorithm 558. In some embodiments, the antenna can be used to transmit and receive signals in a half-duplex format. When the antenna is transmitting, the antenna can be referred to as a transmitting antenna 552, and when the antenna is receiving, the antenna can be referred to as a receiving antenna 554. It should be understood by those of ordinary skill in the art that the same antenna can be a transmitting antenna 552 in some cases and a receiving antenna 554 in other cases. In the case of an antenna array, one or more antenna elements can be used to transmit or receive signals, for example, in a beamforming environment. In some instances, a group of antenna elements for transmitting a composite signal can be referred to as a transmitting antenna 552, and a group of antenna elements for receiving a composite signal can be referred to as a receiving antenna 554. In some instances, each antenna is equipped with its own transmit and receive paths, and depending on whether the antenna is operated as a transmitting antenna 552 or a receiving antenna 554, the transmit and receive paths can be alternately switched to connect to the antenna.

[0284] In one embodiment, the sensing agent 556 may be responsible for determining the sensing measurement parameters and / or transmission parameters for establishing one or more sensing measurements. In an example, the sensing agent 556 may receive the sensing measurement parameters and / or transmission parameters for establishing one or more sensing measurements from the sensing algorithm 558. In an example, the sensing agent 556 may receive sensing measurement results from one or more sensing receivers of the plurality of sensing receivers 502-(1-M), and may process the sensing measurement results to achieve the sensing target. In an example, the sensing agent 556 may receive channel representation information (such as CSI or TD-CRI) from one or more sensing receivers of the plurality of sensing receivers 502-(1-M), and may process the channel representation information to achieve the sensing target. In an embodiment, the sensing agent 556 may receive the sensing measurement results or channel representation information, and may provide the received sensing measurement results or channel representation information to the sensing algorithm 558, and the sensing algorithm 558 may receive the sensing measurement results or channel representation information from the sensing agent 556, and may process the information to achieve the sensing target.

[0285] In some embodiments, receiving the sensing measurements may be performed by an algorithm running in a medium access control (MAC) layer of the remote processing device 506, and processing the sensing measurements to achieve the sensing goal may be performed by an algorithm running in an application layer of the remote processing device 506. In an example, the algorithm running in the application layer of the remote processing device 506 may be referred to as a Wi-Fi sensing agent, a sensing application, or a sensing algorithm. In some embodiments, the algorithm running in the MAC layer of the remote processing device 506 and the algorithm running in the application layer of the remote processing device 506 may run separately on the processor 548. In one embodiment, the sensing agent 556 may pass physical layer parameters (e.g., such as channel representation information, examples of which are CSI and TD-CRI) from the MAC layer of the remote processing device 506 to the application layer of the remote processing device 506, and may use the physical layer parameters to detect one or more features of interest. In one example, the application layer may operate on the physical layer parameters and form a service or feature that may be presented to an end user. According to one embodiment, the communication between the MAC layer of the remote processing device 506 and other layers or components of the remote processing device 506 can be based on a communication interface such as an MLME interface and a data interface. According to some embodiments, the sensing agent 556 can include / execute a sensing algorithm 558. In one embodiment, the sensing agent 556 can use the sensing algorithm 558 to process and analyze the sensing measurement results and identify one or more features of interest. In addition, the sensing agent 556 can be configured to determine the number and timing of sensing transmissions and sensing measurements for the purpose of Wi-Fi sensing. In some embodiments, the sensing agent 556 can be configured to cause one or more sensing transmitters in the plurality of sensing transmitters 504-(1-N) to send the sensing measurement results to one or more sensing receivers in the plurality of sensing receivers 502-(1-M).

[0286] In some embodiments, the system 500 may include a power change information storage device 562. In one embodiment, the power change information storage device 562 may store information related to power changes of links and link combinations. In one example, the information related to power changes of links and link combinations stored in the power change information storage device 562 may be updated periodically or dynamically as needed. Although the power change information storage device 562 has been described as being implemented outside the multiple sensing receivers 502-(1-M) and the multiple sensing transmitters 504-(1-N), in some embodiments, the power change information storage device 562 may be implemented within each of the multiple sensing receivers 502-(1-M) and / or each of the multiple sensing transmitters 504-(1-N).

[0287] In some embodiments, the system 500 may include a sensing information storage device 564. In one embodiment, the sensing information storage device 564 may store sensing probe information. In an example, the sensing probe information may include information about multiple power changes in multiple candidate sensing links between multiple sensing-capable devices and an access point. Each power change may be characterized by a grouping of one or more candidate sensing links that shows a change in received power compared to an average power of a sensing transmission of the corresponding candidate sensing link during one or more sampling instances of an analysis period. In one example, the sensing probe information stored in the sensing information storage device 564 may be updated periodically or dynamically as needed. Although the sensing information storage device 564 has been described as being implemented externally to the multiple sensing receivers 502-(1-M) and the multiple sensing transmitters 504-(1-N), in some embodiments, the sensing information storage device 564 may be implemented within each sensing receiver in the multiple sensing receivers 502-(1-M) and / or each sensing transmitter in the multiple sensing transmitters 504-(1-N). For ease of explanation and understanding, the description provided above may refer to the sensing receiver 502-1 and / or the sensing transmitter 504-1, however, the description is also applicable to one or more sensing receivers among multiple sensing receivers 502-(1-M) and / or one or more sensing transmitters among multiple sensing transmitters 504-(1-N).

[0288] According to one or more embodiments, communications in network 560 may be governed by one or more standards in the 802.11 family of standards developed by IEEE. Some example IEEE standards may include IEEE 802.11-2020, IEEE 802.11ax-2021, IEEE 802.11me, IEEE 802.11az, and IEEE 802.11be. IEEE 802.11-2020 and IEEE 802.11ax-2021 are fully ratified standards, while IEEE 802.11me reflects ongoing maintenance updates to the IEEE 802.11-2020 standard, and IEEE 802.11be defines the next generation standard. IEEE 802.11az is an extension of the IEEE 802.11-2020 and IEEE 802.11ax-2021 standards that adds new functionality. In some embodiments, communications may be governed by other standards (other or additional IEEE standards or other types of standards). In some embodiments, the portion of the system 500 of the network 560 that does not need to be governed by one or more standards in the 802.11 family of standards can be implemented by an instance of any type of network, including a wireless network or a cellular network. In addition, IEEE 802.11ax includes OFDMA, which allows the sensing receiver 502 to send data to all participating devices (such as multiple sensing transmitters 504-(1-N)) simultaneously using a single transmission opportunity TXOP, and vice versa. The efficiency of OFDMA depends on how the sensing receiver 502 reserves channel resources (interchangeably referred to as RUs) and configures transmission parameters between multiple sensing transmitters 504-(1-N). According to one embodiment, the system 500 can be a system that supports OFDMA.

[0289] Return to reference Figure 5According to one or more embodiments, the system 500 may participate in a sensing session. In an example, the sensing session may be a protocol between a sensing initiator and a sensing responder to participate in a WLAN sensing procedure (also referred to as a Wi-Fi sensing procedure). In an example, sensing measurement parameters associated with the sensing session may be determined by the sensing initiator and may be exchanged between the sensing initiator and the sensing responder. In an example, the sensing initiator may be a sensing transmitter 504-1, and the sensing responder may be a sensing receiver 502-1. In an example, the sensing initiator may be a sensing receiver 502-1, and the sensing responder may be a sensing transmitter 504-1. In an example, the sensing initiator may be a remote processing device 506, and both the sensing transmitter 504-1 and the sensing receiver 502-1 may be sensing responders. In an example, the sensing transmitter 504-1 may participate in multiple sensing sessions as a sensing initiator or as a sensing responder. In an example, the sensing receiver 502-1 may participate in multiple sensing sessions as a sensing initiator or as a sensing responder. In an example, the remote processing device 506 may participate in multiple sensing sessions as a sensing initiator.

[0290] Figure 6 An example of a WLAN sensing procedure (also referred to as a Wi-Fi sensing procedure) according to some embodiments is presented. In an example, the WLAN sensing procedure allows a STA to perform WLAN sensing. In an example, the WLAN sensing procedure enables a STA to obtain one or more sensing measurement results of a wireless transmission channel between two or more STAs and / or a wireless transmission channel between a receiving antenna and a transmitting antenna of a STA. In an example, the WLAN sensing procedure consists of one or more of the following: sensing session establishment, sensing measurement establishment, one or more sensing measurement instances, sensing measurement establishment termination, and sensing session termination.

[0291] Figure 6 A sensing session establishment is shown with a STA having MAC ADDR=A and AID=1. In an example, the sensing session establishment establishes a sensing session. In an example, the sensing session may be identified by the AIDs of the STAs involved in the sensing session. Figure 6 The sensing measurement establishment procedure of a STA with MAC ADDR=A is shown, where the sensing measurement establishment ID=1.

[0292] In an example, the sensing measurement setup allows a sensing initiator and a sensing responder to exchange and agree on operational attributes associated with a sensing measurement instance. The sensing initiator may transmit a sensing measurement setup request frame to a sensing responder, the sensing responder intending to perform a sensing measurement setup using the sensing measurement setup request frame. Fig. 7AAn example of a sensing measurement setup request frame is provided in FIG. In the example, the sensing measurement setup request frame is a public action frame and is identified by a public action field value in the example. Fig. 7A As shown in the example shown in , in an embodiment, the sensing measurement setup request frame format may include one or more of the following: a category field, a public action field, a dialog token field, a measurement setup ID field, a DMG sensing measurement setup element field, and a sensing measurement parameter element. In the example, a category value code is defined for a "protected sensing frame". In an embodiment, the protected sensing action field is defined in an octet immediately following the category field to distinguish the protected sensing frame format from the public sensing frame format.

[0293] Figure 7B An example of a sensing measurement parameter element according to some embodiments is shown. In the example, the sensing measurement parameter element indicates an operational attribute of a corresponding sensing measurement instance. In the example, the sensing measurement parameter element includes a sensing measurement parameter field. Figure 7C An example of the format of a sensing measurement parameter field according to some embodiments is shown. In one example, the sensing measurement parameter field includes a sensing transmitter subfield. The sensing transmitter subfield can be set to 1 to indicate that the sensing responder assumes the sensing transmitter role, such as sensing transmitter 504-1. In one example, the sensing responder assumes the sensing transmitter role according to the sensing transmitter subfield of the sensing measurement establishment ID associated with the sensing measurement parameter field. In one example, the sensing measurement parameter field includes a sensing receiver subfield. The sensing receiver subfield can be set to 1 to indicate that the sensing responder assumes the sensing receiver role, such as sensing receiver 502-1. In one example, the sensing responder assumes the sensing receiver role according to the sensing receiver subfield of the sensing measurement establishment ID associated with the sensing measurement parameter field.

[0294] Reference again Figure 7C In an example, if the sensing receiver subfield indicates that the sensing responder should assume the sensing receiver role, the sensing measurement parameter field format includes a sensing measurement report subfield. In an example, the sensing measurement report subfield may indicate whether the sensing responder sends a sensing measurement report frame in a sensing measurement instance generated by the sensing measurement setup.

[0295] Reference again Figure 7C In an example, the sensing measurement parameter field format includes a measurement report type subfield. In an example, the measurement report type subfield indicates the type of measurement result reported in the sensing measurement instance corresponding to the sensing measurement establishment ID, for example, when the sensing initiator is a sensing transmitter (such as the sensing transmitter 504-1).

[0296] In an example, after the sensing responder receives the sensing measurement setup request frame, the sensing responder may send a sensing measurement setup response frame. Fig.7D An example of a sensing measurement setup response frame is provided in the embodiment. In an example, a sensing responder may use a status code field in a sensing measurement setup response frame to indicate whether the sensing responder accepts the requested sensing measurement setup parameters in a received sensing measurement setup request frame. In an embodiment, the status code field may be set to 0, which indicates a successful sensing measurement setup, wherein the sensing responder accepts the operational attributes contained in the sensing measurement setup request frame. In an example, the sensing responder may indicate in a sensing measurement setup response frame that the operational attributes contained in the sensing measurement setup request frame sent by the sensing initiator are not accepted, for example by setting the status code field to a non-zero value. In an example, the sensing responder may indicate preferred sensing measurement parameters in a sensing measurement setup response frame, for example to indicate to the sensing initiator one or more operational attributes preferred by the sensing responder. In an example, the sensing responder may indicate to the sensing initiator that the preferred sensing measurement parameters are contained in the sensing measurement setup response frame by setting the status code field to a non-zero value.

[0297] In an example, the sensing initiator may assign a role to the sensing responder as part of the sensing measurement setup sent in the sensing measurement setup request frame. For example, the sensing initiator may indicate to the sensing responder that the sensing responder will assume the role of a sensing receiver (such as the sensing receiver 502-1) or the role of a sensing transmitter (such as the sensing transmitter 504-1) or the role of the sensing receiver 502-1 and the sensing transmitter 504-1. In an example, the sensing initiator may indicate to the sensing responder whether the sensing responder sends a sensing measurement report frame in the sensing measurement instance. In an embodiment, the role assigned to the sensing responder and / or whether the sensing responder sends a sensing measurement report frame persists until the sensing measurement setup is terminated.

[0298] Reference again Figure 6 A sensing session with a STA identified by STA AID with MAC ADDR=A, AID=1, the sensing measurement establishment is followed by one or more sensing measurement instances and measurement report instances, which may be performed based on a defined set of operational attributes. Figure 6 In the example shown, the one or more sensing measurement instances of the STA with MAC ADDR=A may be assigned a sensing measurement instance ID, for example, the first sensing measurement instance may be assigned a sensing measurement instance ID=1, and the second measurement instance may be assigned a sensing measurement instance ID=2. In the example, the sensing measurement instance may be uniquely associated with the sensing measurement establishment.

[0299] Reference again Figure 6, a second sensing measurement establishment may be initiated for the STA with MAC ADDR=A, which may be identified as sensing measurement establishment ID=2. Like sensing measurement establishment ID=1, sensing measurement establishment ID=2 may be associated with a second set of operational attributes. In an example, after the second sensing measurement establishment, any subsequent one or more sensing measurement instances may be performed based on the first set of operational attributes (sensing measurement establishment ID=1) or the second set of operational attributes (sensing establishment measurement ID=2).

[0300] Reference again Figure 6 , Figure 6 A sensing session establishment is shown with a STA with MAC ADDR=B and UID=2. In an example, the sensing session may be identified by the UID of the STA with MAC ADDR=B. Figure 6 Further illustrated is a sensing measurement setup for a STA with MAC ADDR=B. In the example, the set of operational attributes for the sensing measurement setup for the STA with MAC ADDR=B is the same as the second set of operational attributes established with the STA with MAC ADDR=A, and the sensing measurement setup ID is used for both the STA with MAC ADDR=A and the STA with MAC ADDR=B. That is, the sensing measurement setup ID (which may also be referred to as a sensing measurement setup tag) may be applied to one or more STAs. In the example according to Figure 6 In the example, a subsequent sensing measurement instance associated with sensing measurement establishment ID=2 may be associated with a STA with MAC ADDR=A, a STA with MAC ADDR=B, or both a STA with MAC ADDR=A and a STA with MAC ADDR=B. Figure 6 An example of a one-to-many trigger is shown in , where both AID=1 and UID=2 are associated with a single measurement instance and measurement report (measurement instance ID=2 and measurement setup ID=2).

[0301] In an example, the set of operational attributes of a sensing session may be terminated by executing a sensing measurement setup termination procedure, such as Figure 6 As shown, for a STA with sensing measurement establishment ID=1 and MAC ADDR=A. In this example, the sensing measurement establishment ID of the terminated sensing measurement establishment may be used for subsequent sensing measurement establishments. Figure 6 , where after terminating the sensing measurement establishment ID=1 with the STA of MAC ADDR=A, a sensing measurement establishment ID=1 is established for the STA of MAC ADDR=B. In some embodiments, the sensing session may be terminated using a sensing session termination procedure, such as Figure 6 shown.

[0302] Fig. 8AAn exchange between a sensing initiator and a sensing responder is shown that can be one-to-many or many-to-one. In an example, a measurement instance and / or a measurement report can have a one-to-one (single device to single device) notification or trigger, or can have a one-to-many (single device to multiple devices) notification or trigger. In an example, a measurement instance can have a one-to-one, one-to-many, or many-to-one (many devices to a single device) detection.

[0303] As previously described, a sensing session is a protocol between a sensing initiator and a sensing responder to participate in a WLAN sensing procedure, i.e., a sensing session is paired and, in an instance, may be identified by the MAC addresses of the sensing initiator and sensing responder or by associated AID / UID. Figure 8B Examples of paired exchanges or procedures that may be conducted between a sensing initiator and a sensing responder in relation to a sensing session are shown, including sensing session establishment, sensing measurement establishment, sensing measurement establishment termination, and sensing session termination.

[0304] In an example, the sensing measurement instance of the WLAN sensing procedure may be a triggered based (TB) sensing measurement instance. Fig. 9 Depicted is a message flow of a sensing session of a WLAN sensing procedure according to some examples, the WLAN sensing procedure including a sensing measurement establishment procedure, followed by one or more trigger-based (TB) sensing measurement instances consisting of NDPA probes or trigger frame (TF) probes, followed by a sensing measurement establishment termination procedure. In an example, a TB sensing measurement instance may be used, where a sensing initiator is an AP and one or more non-AP STAs are sensing responders. In an example, a TB sensing measurement instance may include a polling phase, an NDPA probe phase, a trigger frame (TF) probe phase, and a reporting phase.

[0305] Fig. 10A and Fig. 10B Five examples of TB sensing measurement instances are shown. Fig. 10A Example 1 of FIG. 1 shows an example of a TB sensing measurement instance including a polling phase, an NDPA detection phase, and a reporting phase. Fig. 10A Example 2 of FIG. 1 shows an example of a TB sensing measurement example including a polling phase and a TF detection phase. Fig. 10A Example 3 and Fig. 10B Example 4 of FIG. 4 shows two examples of TB sensing measurement instances including a polling phase, an NDPA detection phase, a TF detection phase, and a reporting phase. Fig. 10BExample 5 of shows two TB sensing measurement instances, wherein the first TB sensing measurement instance includes a polling phase, an NDPA detection phase, and a TF detection phase, and the second TB sensing measurement instance includes a polling phase and a reporting phase. In the instance, the TF detection phase of the TB sensing measurement instance may precede the NDPA detection phase of the TB sensing measurement instance, for example, as in Example 4. In the instance, the NDPA detection phase of the TB sensing measurement instance may precede the NDPA detection phase of the TB sensing measurement instance, for example, as in Example 3. In some embodiments, the reporting phase of the second TB sensing measurement instance in Example 5 may be addressed to a sensing responder other than the sensing responder involved in the TF detection phase or the NDPA detection phase of the first TB measurement instance.

[0306] Fig.11A and Fig. 11B 1 is an example of a TB sensing measurement instance with a single AP acting as a sensing initiator and five STAs (referred to as STA 1, STA 2, STA 3, STA 4, and STA 5) that are all sensing responders in the example. In the example, the TB sensing measurement instance includes a polling phase, a TF detection phase, and an NDPA detection phase. In the example, STA 1 and STA 2 are sensing transmitters, such as sensing transmitter 504-1 and sensing transmitter 504-2. Fig.11A and Fig. 11B In the example, STA3, STA 4 and STA 5 are sensing receivers, such as sensing receiver 502-1, sensing receiver 502-2 and sensing receiver 502-3. In the example, during the polling phase, the AP as a sensing initiator transmits a sensing polling trigger frame to STA 1, STA 2, STA3, STA 4 and STA 5. In one embodiment, the sensing transmitter STA 1 (504-1) and the sensing transmitter STA 2 (504-2) respond to the sensing polling trigger frame with an indication that the STA can be used to participate in the sensing measurement instance. In the example, the indication is a CTS-to-self frame. In one embodiment, the sensing receiver STA 3 (502-1) and the sensing receiver STA 4 (502-2) respond to the sensing polling trigger frame with an indication that the STA can be used to participate in the sensing measurement instance. In the example, the indication is a CTS-to-self frame. In the example, the sensing receiver STA 5 (502-3) does not respond to the sensing polling trigger frame sent by the AP as the sensing initiator, which indicates that STA 5 (502-3) will not participate in the sensing measurement instance.

[0307] Fig.11A and Fig. 11BThe sensing measurement instance includes a TF detection phase. In the instance, in the TF detection phase, the AP as a sensing initiator sends a sensing detection trigger frame to the sensing transmitter STA 1 (504-1) and the sensing transmitter STA 2 (504-2). In the instance, before sending the sensing detection trigger frame, one or more SIFS periods pass between the AP receiving CTS-to-self frames from STA 1, STA 2, STA 3 and STA 4. In the instance, in response to receiving the sensing detection trigger frame, the sensing transmitter STA 1 (504-1) and the sensing transmitter STA 2 (504-2) send a sensing transmission to the AP. In the instance, the sensing transmission may include an NDP transmission. In the instance, one or more NDP transmissions in the NDP transmission to the AP may be an R2INDP transmission (such as Fig.11A and Fig. 11B ). In the example, one or more SIFS periods of time pass between the sensing transmitter STA 1 (504-1) receiving the sensing detection trigger frame and transmitting the sensing transmission, and in the example, one or more SIFS periods of time pass between the sensing transmitter STA 2 (504-2) receiving the sensing detection trigger frame and transmitting the sensing transmission. In the example, the AP can assume the role of the sensing receiver 502-4, and the AP can perform sensing measurements on the sensing transmissions from the sensing transmitter STA 1 (504-1) and the sensing transmitter STA 2 (504-2).

[0308] Reference again Fig.11A and Fig. 11B , in the NDPA detection phase, the AP acting as a sensing initiator assumes the role of a sensing transmitter (504-3). In an example, the AP as a sensing transmitter 504-3 sends a sensing transmission. In an example, the sensing transmission may be a broadcast transmission. In an example, the sensing transmission may be a unicast transmission to one or more STAs (e.g., to sensing receiver STA 3 (502-1) and / or to sensing receiver STA 4 (502-2)). In an example, one or more SIFS periods have passed between when the AP as a sensing transmitter 504-3 sends a sensing NDPA frame and when the AP as a sensing transmitter 504-3 sends one or more sensing transmissions. In an example, one or more sensing transmissions in the sensing transmission may be full-bandwidth NDP frames. In an example, one or more sensing transmissions in the sensing transmission may be partial-bandwidth NDP frames. In an example, one or more NDP frames in the NDP frame may be I2R NDP frames.

[0309] In an example, the sensing measurement instance of the WLAN sensing procedure may be a non-trigger based (non-TB) sensing measurement instance. Fig.12Depicted is a message flow of a sensing measurement setup procedure according to some embodiments, followed by one or more non-TB sensing measurement instances of a WLAN sensing procedure consisting of one or more of downlink sounding or uplink sounding, followed by a sensing measurement setup termination procedure according to some instances. In an instance, a non-TB sensing measurement instance may be used where the sensing initiator is a non-AP STA and the AP is a sensing responder. In an example, Fig.12 In the example of uplink sounding shown, a sensing initiator (non-AP STA) acting as a sensing transmitter (e.g., sensing transmitter 504-1) sends a sensing announcement frame followed by a sensing transmission. In an example, the sensing announcement frame can be an NDPA frame. In an example, the sensing transmission can be an NDP frame. In an example, in response to receiving the sensing transmission, an AP acting as a sensing receiver (e.g., sensing receiver 502-1) can send a sensing measurement report to the sensing initiator (non-AP STA acting as sensing transmitter 504-1), such as one or more sensing measurement report frames. In the example of uplink sounding shown, a sensing initiator (non-AP STA acting as sensing transmitter 504-1) sends a sensing announcement frame followed by a sensing transmission. In the example, the sensing announcement frame can be an NDPA frame. In the example, the sensing transmission can be an NDP ... Fig.12 In the example of downlink sounding shown, a sensing initiator (non-AP STA) acting as a sensing receiver (e.g., sensing receiver 502-1) sends a sensing announcement frame. In an example, the sensing announcement frame can be an NDPA frame. In an example, in response to receiving the sensing announcement frame, an AP acting as a sensing transmitter (e.g., sensing transmitter 504-1) can send one or more sensing transmissions. In an example, one or more of the sensing transmissions can be NDP frames. In an example, in response to receiving the sensing transmission, a non-AP STA acting as a sensing receiver (502-1) can perform sensing measurements on the sensing transmission. In an example, the sensing measurement establishment can be terminated by a sensing initiator or a sensing responder that sends a SENS measurement establishment termination frame. In an example, the sensing responder or the sensing initiator (respectively) can respond with an acknowledgment.

[0310] Fig.13A detailed example of a non-TB sensing measurement example according to some embodiments is shown. In the example, STA 1 acting as a sensing initiator and a sensing transmitter (such as sensing transmitter 504-1) sends a sensing announcement frame. In the example, the sensing announcement frame may be a sensing NDPA frame. In the example, one or more SIFS may have passed after STA 1 acts as a sensing initiator and a sensing transmitter (such as sensing transmitter 504-1) sends one or more sensing transmissions. In the example, one or more sensing transmissions in the sensing transmission may be an NDP frame. In an example. STA 1 acting as a sensing initiator and a sensing receiver (such as sensing receiver 502-1) sends a sensing announcement frame. In the example, the sensing announcement frame may be a sensing NDPA frame. In the example, one or more SIFS may have passed after AP 1 acts as a sensing responder and a sensing transmitter (such as sensing transmitter 504-1) sends one or more sensing transmissions. In the example, one or more sensing transmissions in the sensing transmission may be an NDP frame.

[0311] Fig.14 An example of a sensing measurement report frame is shown. In some embodiments, the sensing measurement report frame is a public action category or a public action unconfirmed category. In some examples, the sensing measurement report frame can be transmitted to provide WLAN sensing measurement results, for example, to a sensing agent or a sensing algorithm of a sensing initiator. In an example, the sensing measurement report frame can include one or more sensing measurement report elements. In some embodiments, the sensing measurement report element can include a single sensing measurement report. In an example, the sensing measurement report element can include a sensing measurement report type field, and the sensing measurement report type field can contain a number identifying the type of the sensing measurement report. For example, a value of 0 can indicate that the sensing measurement type is a CSI measurement result, and a non-zero value can indicate that the sensing measurement type is a TD-CRI measurement result.

[0312] Reference again Fig.14 In an embodiment, the sensing measurement report element may include a sensing measurement report control field. In an example, the sensing measurement report control field may contain information required to interpret the sensing measurement report field. For example, the sensing measurement report control field format may include one or more subfields. In an embodiment, one or more subfields of the sensing measurement report control field may contain PHY layer parameters used by a sensing receiver when performing sensing measurements, such as receiver antenna beamforming or spatial layer information.

[0313] In a sensing session, transmissions may be exchanged between one or more sensing receivers of the plurality of sensing receivers 502-(1-M) and one or more sensing transmitters of the plurality of sensing transmitters 504-(1-N). In one instance, the MAC layer of the IEEE 802.11 stack may be utilized to control these transmissions. According to one embodiment, one or more sensing receivers of the plurality of sensing receivers 502-(1-M) may protect a TXOP that may be allocated to one or more sensing transmissions by one or more sensing transmitters of the plurality of sensing transmitters 504-(1-N). According to one embodiment, one or more sensing receivers of the plurality of sensing receivers 502-(1-M) may allocate channel resources (or RUs) within a TXOP to one or more sensing transmitters of the plurality of sensing transmitters 504-(1-N). In one example, one or more of the plurality of sensing receivers 502-(1-M) may allocate channel resources to one or more of the plurality of sensing transmitters 504-(1-N) by allocating time and bandwidth within a TXOP to the one or more of the plurality of sensing transmitters 504-(1-N).

[0314] According to one embodiment, FIG. 15A to FIG. 15H An example 1500 of a field hierarchy within a sensing trigger message is shown.

[0315] like Fig.15A As described, the common information field may contain information that is common to one or more of the plurality of sensing transmitters 504-(1-N). According to one embodiment, the requirement for an NDPA prior to an NDP may be optional. This may be indicated to one or more of the plurality of sensing transmitters 504-(1-N), and may be encoded, for example, in a "trigger-related common information" field if the requirement is common to the plurality of sensing transmitters 504-(1-N), or may be encoded in a "trigger-related user information" field if the requirement is specific to one or more of the plurality of sensing transmitters 504-(1-N). According to one example, the requirement for a sensing announcement (e.g., and NDPA) prior to a sensing response NDP may be encoded by a single bit, where 0 (bit clear) indicates that the sensing announcement is optional, and 1 (bit set) indicates that the sensing announcement is required.

[0316] like Fig. 15BAs described, a trigger type representing a sensing trigger message (within B0..3 of the "common information" field) can be defined. In an example, the trigger type subfield value of any reserved value of the sensing trigger message can be 9-15, for example, the trigger type subfield value of the sensing trigger message can be 9. In an example of triggering a sensing transmission from a sensing transmitter 504-1, the trigger-related user information field can contain sensing trigger message data. In one embodiment, a time-synchronized sensing transmission in response to a sensing trigger message from multiple sensing transmitters 504-(1-N) may be required. In an example, a requirement for one or more time-synchronized sensing transmissions can be encoded into the trigger-related public information field. According to an example, a requirement for one or more time-synchronized sensing transmissions can be encoded by a single bit, where 0 (bit clear) represents a request for a normal or non-time-synchronized response, and 1 (bit set) represents a request for a time-synchronized response. In some examples, a method of time synchronization can be requested in a sensing trigger. In an example, the method of time synchronization to be requested can be encoded into the trigger-related public information field. In an example, the encoding can use two bits as shown in the following table.

[0317] coding method describe 00 A The Sensing Advertisement is followed by the Sensing NDP. 01 B The padding is followed by the Sensing Response message. 10 C NDP is sensed without an initial sense announcement. 11 not applicable For future use or expansion.

[0318] like Fig. 15C As described above, the sensing trigger message may have an uplink bandwidth (UL BW) subfield value of 0, 1, 2, or 3 corresponding to a bandwidth of 20 MHz, 40 MHz, 80 MHz, or 80+80 MHz (160 MHz).

[0319] like Fig.15D The user information list contains information specific to each sensing transmitter in the plurality of sensing transmitters 504-(1-N). In an example, the user information list may include the AID of the sensing transmitter, the RU allocation for the sensing transmitter, and other trigger-related user information.

[0320] like Fig.15E As stated, Fig.15D The AID12 subfield of the user information list shown in may be used to address a specific sensing transmitter among the plurality of sensing transmitters 504 -( 1 -N).

[0321] like Fig.15F and Figure 15G The RU allocation subfield is used to allocate a resource unit (RU) to each of the plurality of sensing transmitters 504-(1-N).

[0322] like Fig.15HThe trigger-related user information subfield may be used to request a transmission configuration and / or a steering matrix configuration of one or more sensing transmitters among the plurality of sensing transmitters 504-(1-N) being triggered by the sensing trigger message.

[0323] In the following description, reference is made to the sensing algorithm 558 on the remote processing device 506 in the processing of channel representation information. In all instances, the processing of channel representation information may alternatively or additionally be performed by a sensing agent 556 on the remote processing device 506 and / or by a sensing agent 516-(1-M) and / or a sensing algorithm 518-(1-M) on one or more of the plurality of sensing receivers 502-(1-M) and / or by a sensing agent 536-(1-N) and / or a sensing algorithm 538-(1-N) on one or more of the plurality of sensing transmitters 504-(1-N).

[0324] Fig.16 A representation 1600 is shown of communicating the location of one or more selected time domain pulses from one or more of the plurality of sensing receivers 502-(1-M) to a sensing algorithm 558 on a remote processing device 506 using an active tone bitmap. Fig.28 In the example of , the active tone bitmap sent from one or more of the plurality of sensing receivers 502-(1-M) to the sensing algorithm 558 is 10 bits long, corresponding to 10 pilot and data tones for a 16-point FFT. The value “1110111011” of the active tone bitmap indicates that 8 filtered time domain channel representation information (TD-CRI) values ​​will follow (because there are 8 “1”s in the active tone bitmap), and the sensing algorithm 558 should arrange the received filtered TD-CRI in 10 tones by applying each filtered TD-CRI to the reconstructed filtered TD-CRI tone in sequence according to the active tone bitmap, i.e., TD-CRI 1 in tone 1, TD-CRI 2 in tone 2, TD-CRI 3 in tone 3, null in tone 4, TD-CRI 4 in tone 5, TD-CRI 5 in tone 6, TD-CRI 6 in tone 7, null in tone 8, TD-CRI 7 in tone 9, and TD-CRI 8 in tone 10.

[0325] Fig.17A representation 1700 is shown of using a full bitmap to communicate the location of one or more selected time domain pulses from one or more sensing receivers 502-(1-M) to a sensing algorithm 558. In one example, the full bitmap can be equal to the total number of tones in the full TD-CRI, including guard tones and DC tones, i.e., 64 bits for a 20 MHz channel bandwidth and 128 bits for a 40 MHz channel bandwidth. In the example, some of the most significant bits (MSBs) will be "0" to account for guard tones, and some of the least significant bits (LSBs) will also be "0" to account for direct current (DC) tones and guard tones. Fig.17 In the 16-point Fast Fourier Transform (FFT) example shown, zeros are placed in the first three positions of the full bitmap, followed by eight TD-CRI positions, followed by another three zeros.

[0326] According to some embodiments, for each filtered TD-CRI, one or more of the plurality of sensing receivers 502-(1-M) may send three values ​​instead of two values ​​(the first value is the amplitude of the complex number, and the second value is the phase of the complex number) to the sensing algorithm 558 on the remote processing device 506. In one example, the third value may represent the location of the filtered TD-CRI value in the reconstructed filtered TD-CRI. In one example, the number of bits used to represent the third value may vary according to the channel bandwidth and therefore may vary according to the number of points in the full TD-CRI. For example, if the channel bandwidth is 20MHz, a 64-point FFT may be required, and therefore the additional value may be 6 bits long. If the channel bandwidth is 40MHz, a 128-point FFT is required, and therefore the additional value may be 7 bits long. In one example, the additional value may precede the value of the filtered TD-CRI. In some examples, the additional value may follow the value of the filtered TD-CRI. In one example, the number of bits used for the filtered TD-CRI can be determined based on the resolution of the actual CSI output by the baseband receiver.

[0327] Fig.18 A representation 1800 is shown of communicating the location of the selected one or more time domain pulses (filtered TD-CRI) from one or more of the plurality of sensing receivers 502-(1-M) to a sensing algorithm 558 on a remote processing device 506 using the location of the selected one or more time domain pulses (filtered TD-CRI) in the full TD-CRI in accordance with some embodiments. Fig.18 In the example of , the numbering of symbols has been moved to start at "0" and end at "15" to facilitate mapping the symbols to the third value. Figures 16 to 18An example of transmitting selected one or more time-domain pulse signaling using a 16-point FFT with 3 guard tones on either side (leaving 10 tones for pilot and data symbols) is shown, however, the description is equally applicable to 32-point FFTs, 64-point FFTs, 128-point FFTs, 256-point FFTs, 512-point FFTs, 1024-point FFTs, and any other number of points in the FFT and a variable number of guard tones.

[0328] According to one embodiment, in response to receiving a representation of the position of one or more selected time domain pulses in the full TD-CRI, the sensing algorithm 558 on the remote processing device 506 can be configured to construct a reconstructed filtered TD-CRI before performing an FFT to create a reconstructed CSI (R-CSI). In one example, the correctly located reconstructed filtered TD-CRI creates an R-CSI when converted back to the frequency domain by an FFT. In one embodiment, since the filtered TD-CRI is much less than the CSI value, the amount of information that needs to be transmitted to the sensing algorithm 558 as CRI in the air is significantly reduced without losing the fidelity of the information that would impair the performance of the sensing algorithm 558. For example, for 52 CSI values ​​(representing a 20MHz channel bandwidth), 10 to 15 time domain pulses in the filtered TD-CRI can be used to accurately represent the transmission channel with minimal loss of fidelity. Therefore, minimizing the amount of information that needs to be sent minimizes the overhead placed on the network 560 by the system 500.

[0329] According to aspects of the present disclosure, the amount of information passed from one or more of the sensing receivers 502-(1-M) to the sensing algorithm 558 on the remote processing device 506 can be significantly reduced by sending filtered time domain values ​​(filtered TD-CRI, one complex value per time domain pulse) instead of the frequency domain CSI values ​​provided by the baseband receiver. In addition, the number of time domain pulses that need to be sent can be about 25% or less of the CSI value for the minimum channel bandwidth (e.g., 20MHz channel bandwidth). In addition, this percentage may decrease significantly as the total channel bandwidth increases.

[0330] According to one embodiment, a sensing agent (e.g., a sensing agent 516-(1-M) on one or more of the plurality of sensing receivers 501-(1-M) or a sensing agent 556 on the remote processing device 506) may store the set of time domain pulses constituting the full TD-CRI of the filtered TD-CRI as a difference between the set of time domain pulses of the full TD-CRI and the corresponding time domain pulses of the sensing imprint as an imprint increment defining the filtered TD-CRI. In one embodiment, the imprint increment values ​​constituting the filtered TD-CRI may be represented by a digital format having fewer bits than required to represent the complete time domain pulses of the filtered TD-CRI. According to one example, since the range of the represented values ​​is reduced by the difference operation, there may be no or little loss of precision.

[0331] In one embodiment, once the fingerprint increment is obtained, the sensing agent (e.g., the sensing agent 516-(1-M) on one or more of the multiple sensing receivers 502-(1-M) or the sensing agent 556 on the remote processing device 506) can evaluate the fingerprint increment separately for each time domain pulse of the full TD-C506RI. According to one embodiment, the sensing agent (e.g., the sensing agent 516-(1-M) on one or more of the multiple sensing receivers 502-(1-M) or the sensing agent 556 on the remote processing device 506) can compare each time domain pulse difference (i.e., the difference between the time domain pulse of the full TD-CRI and the time domain pulse of the sensing fingerprint) with a measured fingerprint increment threshold for amplitude or for phase or for both amplitude and phase. Based on the comparison result, the sensing agent (e.g., the sensing agent 516-(1-M) on one or more of the multiple sensing receivers 502-(1-M) or the sensing agent 556 on the remote processing device 506) can determine that the time domain pulse of the full TD-CRI has changed. In one instance, when the measurement mark increment threshold is exceeded only once, the sensing agent (e.g., the sensing agent 516-(1-M) on one or more of the multiple sensing receivers 502-(1-M) or the sensing agent 556 on the remote processing device 506) can determine that the time domain pulse of the full TD-CRI has changed. According to one embodiment, the measurement mark increment threshold must exceed the measurement mark increment count of the subsequent measurement before the time domain pulse of the full TD-CRI is considered different from the time domain pulse of the sensing mark. In one instance, the measurement mark increment count may refer to the number of times the measurement mark increment threshold is exceeded before the time domain pulse of the full TD-CRI is considered different from the time domain pulse of the sensing mark. Any of the previously described functions may alternatively or additionally be performed by a sensing algorithm (e.g., a sensing algorithm 518-(1-M) on one or more of the plurality of sensing receivers 502-(1-M) or a sensing algorithm 558 on the remote processing device 506).

[0332] In one embodiment, the measurement imprint increment threshold and the measurement imprint increment count may be configured by the sensing receiver 502-1. In some embodiments, the measurement imprint increment threshold and the measurement imprint increment count may be configured by the sensing algorithm 558. According to one embodiment, the sensing algorithm 558 may send one or more measurement imprint increment thresholds and corresponding one or more measurement imprint increment counts to the sensing receiver 502-1. According to one embodiment, when the sensing receiver 502-1 is initially associated with the sensing algorithm 558, the sensing algorithm 558 may transmit one or more measurement imprint increment thresholds and corresponding one or more measurement imprint increment counts to the sensing receiver 502-1 for use in future Wi-Fi sensing sessions. In one instance, the one or more measurement imprint increment thresholds may be associated with a specific sensing imprint. For example, the measurement imprint increment threshold may be associated with a sensing imprint for an uplink path between the sensing transmitter 504-1 and the sensing receiver 502-1 in a specific channel bandwidth and a sensing imprint for a specific delivered transmission configuration.

[0333] According to an embodiment, as a representation of the reflection of the propagation channel between the sensing receiver 502-1 and the sensing transmitter 504-1 for Wi-Fi sensing, the sensing receiver 502-1 may send a filtered TD-CRI to the sensing algorithm 558. In an embodiment, the sensing agent 516-1 may send the filtered TD-CRI to the sensing algorithm 558 via a CRI transmission message. In an example embodiment, the sensing agent 516-1 may send a CRI transmission message containing the filtered TD-CRI to the sensing algorithm 558 via the transmit antenna 512-1. In an example, the filtered TD-CRI may contain a time domain pulse of the full TD-CRI to the sensing algorithm 558, which is determined to have changed from the sensing footprint (the time domain pulse of the full TD-CRI that is different from the sensing footprint may be transmitted to the sensing algorithm 558). In some instances, the filtered TD-CRI may contain a fingerprint delta value representing a time domain pulse of the full TD-CRI that is determined to have changed from the sensing fingerprint (the fingerprint delta of the changed time domain pulse of the full TD-CRI may be transmitted to the sensing algorithm 558).

[0334] According to an embodiment, the sensing agent 516-1 may indicate to the sensing algorithm 558 the location of a time domain pulse within the filtered TD-CRI that represents a reflection in the propagation channel (ie, a time domain pulse or a time domain tone represented by a footprint increment).

[0335] In one embodiment, to avoid using a longer data field (e.g., a media access control protocol data unit (MPDU)) than necessary to send the filtered TD-CRI from the sensing receiver 502-1 to the sensing algorithm 558, the filtered TD-CRI time domain pulses or footprint increment values ​​can be arranged continuously in the data message without gaps or nulls between them. However, there may be gaps between the actual updated or selected full TD-CRI time domain pulses, and therefore the original position of the selected full TD-CRI time domain pulses must be signaled from the sensing receiver 502-1 to the sensing algorithm 558. In one example, the updated or selected full TD-CRI time domain pulses can refer to time domain pulses of the full TD-CRI that are different from the sensing footprint.

[0336] According to one embodiment, the sensing agent 516-1 can transmit a location bitmap indicating the location of the first time domain pulse in the full TD-CRI to the sensing algorithm 558. In one example, the first time domain pulse can be a series of time domain pulses from within the full TD-CRI that have changed compared to the sensing footprint and will be processed by the sensing algorithm 558 to determine the current sensing measurement result. Therefore, each time domain pulse must be identified to allow the generation of a reconstructed full TD-CRI and reconstruction of the sensing measurement at the sensing algorithm 558.

[0337] Fig.23 A diagram 2300 of a filtered TD-CRI according to some embodiments is depicted. An example of a time domain pulse in a sensing footprint is shown using a solid arrow (denoted as "2302"), and an example variation of the sensing footprint in three time domain pulses is shown using a dashed arrow (denoted as "2304"). For clarity, the Fig.23 In an example, a series of selected full TD-CRI time domain values ​​other than the sensing footprint are located within a window denoted as "2306". In an example, the bandwidth of the propagation channel between the sensing receiver 502-1 and the sensing transmitter 504-1 may be 20 MHz and may be represented by 52 complex time domain pulses in the full TD-CRI.

[0338] According to one embodiment, the sensing agent 516-1 can create a bitmap representing the length required for all time domain pulses carrying data. In one example, the bitmap can be 52 bits long. In other examples, the bitmap can be 104 bits long. In one example, the sensing agent 516-1 can fill the bitmap with "1" when a time domain pulse has been selected and exists, and fill the bitmap with "0" when a time domain pulse has not been selected and does not exist. In one example, the MSB of the bitmap refers to the first time domain tone, and the LSB of the bitmap refers to the last time domain tone.

[0339] refer to Fig.23 In the example, a 52-bit long bitmap (or 52-bit bitfield) is created as follows:

[0340] 0000000000000000110100000000000000000000000000000000

[0341] In one embodiment, three updated time domain pulses (amplitude and phase) are transmitted in sequence. In one example, the updated time domain pulses can be passed as the value of the corresponding value in the alternative sensing imprint. In some examples, the imprint increment can be passed to apply as the change of the corresponding value in the sensing imprint. The type of the update transmitted can be signaled by the additional bit in the bit field. In one example, the value of the additional MSB can represent the type of the update transmitted. According to one embodiment, in order to utilize the potential of the low information content in the bit field, the sensing agent 516-1 can use a lossless data compression algorithm to reduce the number of bits transmitted. An example of a lossless data compression algorithm is run length encoding.

[0342] In one example, the bitmap may be equal to the number of tones in the FFT including the guard tone and the DC tone, i.e., 64 bits for the example of a 20 MHz propagation channel bandwidth and 128 bits for the example of a 40 MHz propagation channel bandwidth. In the example, the first digit of the MSB will be "0" to account for the guard tone, and the second digit of the LSB will also be "0" to account for the DC tone and the guard tone. According to one embodiment, it may be assumed that the MSB of the bitmap maps to the first symbol of the FFT. Based on the assumption, the time domain pulse or stamp increment value may be filled in according to the bitmap.

[0343] According to some embodiments, for each time domain pulse in the filtered TD-CRI, the sensing agent 516-1 may send three values ​​instead of two values, wherein one of the three values ​​may represent the location of the time domain pulse or the imprint increment value in the full TD-CRI. In one instance, the number of bits used to represent the additional value (i.e., the third value) or the size of the additional value may change according to the propagation channel bandwidth and the number of time domain pulses in the TD-CRI. For example, if the propagation channel bandwidth is 20MHz and a 64-point FFT is required, the additional value may be 6 bits long. If the propagation channel bandwidth is 40MHz and a 128-point FFT is required, the additional value may be 7 bits long. In an example, the additional value may precede the value of the time domain pulse or the imprint increment value. In some instances, the additional value may follow the value of the time domain pulse or the imprint increment value.

[0344] In one example, the type of the values ​​of the filtered TD-CRI passed (i.e., those values ​​that replace the corresponding time-domain pulse values ​​in the sensing imprint or those values ​​that reflect changes to the corresponding values ​​in the sensing imprint) is signaled by a dedicated type update field that is passed along with the value itself.

[0345] Fig.24 depicts an example of a set 2400 (selected time domain pulses) of altered time domain pulses in a full TD-CRI according to some embodiments, and Fig.25 Another example of a set 2500 (stamp increment) of a changed time domain pulse in a full TD-CRI is depicted. In one example, it can be assumed that there are no guard tones or DC tones before the start of the time domain representation. In both depictions, parameters representing the positions of the changed time domain pulses in the TD-CRI are transmitted together with the changed time domain pulses.

[0346] According to one embodiment, the sensing algorithm 558 may receive a filtered TD-CRI from the sensing receiver 502-1. In one instance, the filtered TD-CRI may include multiple time domain pulses. In one embodiment, the sensing algorithm 558 may receive a sensing imprint indicator and the filtered TD-CRI. In one instance, the sensing imprint indicator may refer to a version number or unique identifier of the sensing imprint used by the sensing receiver 502-1 to calculate the filtered TD-CRI. In one embodiment, the sensing algorithm 558 may also receive a position bitmap indicating the position of the corresponding time domain pulses in the sensing imprint. In some embodiments, the sensing algorithm 558 may receive a cryptographic hash of the sensing imprint used by the sensing receiver 502-1 to calculate the filtered TD-CRI and the filtered TD-CRI to allow the sensing algorithm 558 to determine which sensing imprint to use.

[0347] According to one embodiment, upon receiving the filtered TD-CRI and the sensing imprint indicator and / or the cryptographic hash, the sensing algorithm 558 may obtain the sensing imprint (or a copy of the sensing imprint) from the data storage device according to the sensing imprint indicator and / or the cryptographic hash. In one embodiment, the sensing algorithm 558 may generate a reconstructed TD-CRI from the filtered TD-CRI and the sensing imprint. According to one embodiment, the sensing algorithm 558 may generate a reconstructed TD-CRI by replacing the corresponding time domain pulses of the sensing imprint with the multiple time domain pulses received in the filtered TD-CRI. The sensing algorithm 558 may then perform an FFT on the resulting time domain signal to obtain a nearly accurate frequency domain CSI. Subsequently, the sensing algorithm 558 may detect the features of interest in the sensing space according to the reconstructed frequency domain channel representation.

[0348] In some embodiments, the filtered TD-CRI may include a footprint increment that stores the time domain pulse difference. Upon receiving the filtered TD-CRI, the sensing algorithm 558 may generate a reconstructed TD-CRI by adding the time domain pulse difference to the corresponding time domain pulse of the sensing footprint. In one instance, the sensing algorithm 558 may use phasor addition to add the footprint increment to the corresponding time domain pulse in the sensing footprint. The phasor addition operation is opposite to the phasor subtraction operation. In one instance, when the numerical representation of the footprint increment is modified to reduce the number of bits to be transmitted, the footprint increment is then first converted to the numerical format and resolution of the corresponding time domain pulse in the stored copy of the sensing footprint to allow phasor addition without numerical errors. Thereafter, the sensing algorithm 558 may perform an FFT on the resulting time domain signal to obtain a nearly accurate frequency domain CSI. Subsequently, the sensing algorithm 558 may detect the features of interest in the sensing space based on the reconstructed frequency domain channel representation.

[0349] In instances where the sensing algorithm 558 (whether the sensing imprint indicator or the cryptographic hash) cannot identify the sensing imprint for determining the filtered TD-CRI, then the time domain pulse or the imprint delta value may be discarded. In some embodiments, the sensing algorithm 558 may send a message to the sensing receiver 502-1 to invalidate the stored sensing imprint. In some embodiments, if the sensing algorithm 558 (whether the sensing imprint indicator or the cryptographic hash) cannot identify the sensing imprint for determining the filtered TD-CRI and sends the time domain pulse (instead of the imprint delta value), the sensing algorithm 558 may use a lossy time domain compression technique instead of a lossless time domain compression technique.

[0350] According to one embodiment, it may be necessary to recalculate or update the sensing footprint used by the sensing algorithm 518-1 to calculate the reconstructed TD-CRI or the sensing footprint used by the sensing receiver 502-1 to calculate the filtered TD-CRI, for example, a scenario in which the sensing receiver 502-1 detects a moving object in the propagation channel between the sensing receiver 502-1 and the sensing transmitter 504-1, thereby generating a footprint increment between the full TD-CRI and the sensing footprint, and then the object causing the footprint increment stops moving but stays in the sensing space. In such scenarios, the baseline sensing footprint formed before the object enters the sensing space is no longer valid. When the object is no longer moving, the footprint increment is likely to change very little from one sensing measurement to another, and therefore there will be repeated transmissions of the same or similar information from the sensing receiver 502-1 to the sensing algorithm 558. In such scenarios, a new sensing footprint can be determined. In one example, updating the sensing footprint can result in the creation of a new sensing footprint.

[0351] According to one embodiment, when a new sensing footprint is needed, the sensing receiver 502-1 can generate a new sensing footprint based on a sensing transmission that normally occurs and is not specifically requested for the purpose of generating a new sensing footprint. In one example, where the sensing footprint includes versions for multiple delivered transmission configurations, the sensing receiver 502-1 can only update the version of the sensing footprint corresponding to the delivered transmission configuration in use. In some examples, the sensing receiver 502-1 can determine that the complete sensing footprint between the sensing receiver 502-1 and the sensing transmitter 504-1 (i.e., for all delivered transmission configurations) is to be updated. In such a scenario, the sensing receiver 502-1 can request a sensing transmission with the required requested transmission configuration.

[0352] In one embodiment, when the sensing receiver 502-1 determines that a new sensing footprint is needed, the new sensing footprint can be determined as the channel impulse response at the point where the rate of change of the footprint increment of the time domain pulse drops below the footprint increment derivative threshold to reach the required footprint increment derivative period. In some instances, the new sensing footprint can be the average of the sensing footprint average count channel impulse response after the rate of change of the footprint increment drops below the footprint increment derivative threshold. In one embodiment, the sensing algorithm 518-1 can configure the sensing footprint average count of the sensing measurements made on the sensing transmission from the sensing transmitter 504-1, and the sensing transmission shares a commonly delivered transmission configuration that is averaged to reduce noise (e.g., measurement noise). The resulting average full TD-CRI can become the sensing footprint for the delivered transmission configuration and the sensing transmitter 504-1 that generated the sensing transmission on which the sensing measurement was made.

[0353] According to one embodiment, if it is determined that the sensing receiver 502-1 or the sensing transmitter 504-1 has moved (e.g., based on detecting a complete change in the footprint increment, or by detecting a power outage event, or due to a change in the media access control (MAC) address of the sensing receiver 502-1 or the sensing transmitter 504-1), the sensing algorithm 558 may create one or more new sensing footprints for the propagation channels involving the reconfigured sensing receiver 502-1 or the sensing transmitter 504-1. Additionally, in the event that a new sensing transmitter is added to the system 500, the sensing algorithm 558 may create one or more new sensing footprints for the propagation channels involving the new sensing transmitter.

[0354] Some embodiments of the present disclosure as described above define sensing message types for Wi-Fi sensing, namely, a sensing configuration message, a sensing configuration response message, an incremental CRI message, and a sensing imprint transmission message.

[0355] In one example, the sensing configuration message and the sensing configuration response message are carried in a new extension to management frames of the type described in IEEE 802.11. Fig.19 An example of components of a management frame carrying a sensing transmission is shown. In one example, the system 500 may require an acknowledgment frame and the management frame carrying the sensing message may be implemented as an action frame, and in another example, the system 500 may not require an acknowledgment frame and the management frame carrying the sensing message may be implemented as an action No Ack frame.

[0356] In one embodiment, the information content of all sensor message types can be expressed as follows: Fig.19 In some examples, such as Fig.19 The transmission configuration, timing configuration, steering matrix configuration, and TD-CRI configuration described in are implemented as IEEE 802.11 elements. In some examples, the TD-CRI configuration element is part of the transmission configuration element.

[0357] In one or more embodiments, according to some embodiments, the sensing message type may be identified by a message type field, and each sensing message type may carry other identified elements.

[0358] In one example, the data may be encoded as an element for inclusion in a sensing message between a sensing receiver 502-1, a sensing transmitter 504-1, and a sensing algorithm 558. In a measurement activity involving multiple sensing receivers and multiple sensing transmitters, these parameters may be defined for all sensing receiver-sensing transmitter pairs. In one example, when these parameters are transmitted from the sensing algorithm 558 or the sensing transmitter 504-1 including the sensing algorithm 558 to the sensing receiver 502-1, then these parameters configure the sensing receiver 502-1 to process the sensing transmission and calculate the sensing measurement results. In some examples, when these parameters are transmitted from the sensing receiver 502-1 to the sensing algorithm 558 or the sensing transmitter 504-1 including the sensing algorithm 558, then these parameters report the configuration used by the sensing receiver 502-1.

[0359] According to some embodiments, the sensing transmission announcements may be carried in new extensions to control frames of the type described in IEEE 802.11. In some embodiments, the sensing transmission announcements may be carried in new extensions to control frame extensions described in IEEE 802.11. Fig. 20A shows an example of the format of a control frame, and Fig. 20BThe format of the sensing transmission control field of the control frame is shown. In one example, the STA information field of the sensing transmission control field can address up to n sensing receivers by their association ID (AID). In an example embodiment, the sensing transmission announcement can address n sensing receivers required to make sensing measurements and relay channel representation information back to the sensing initiator.

[0360] According to some embodiments, the Sensing Measurement Poll may be carried in a new extension to a control frame of the type described in IEEE 802.11. In some embodiments, the Sensing Measurement Poll may be carried in a new extension to a control frame extension described in IEEE 802.11. Fig.21A shows an example of the format of a control frame, and Fig. 21B The format of the Sensing Measurement Control field of the Control frame is shown.

[0361] According to some embodiments, when the sensing receiver 502-1 has calculated the sensing measurements and created the channel representation information (e.g., in the form of a filtered TD-CRI), it may be desirable for the sensing receiver 502-1 to transmit the channel representation information to the sensing algorithm 558 or the sensing transmitter 504-1 including the sensing algorithm 558. In an example, the sensing measurements may be processed as described to form the channel representation information in the form of a sensing footprint and subsequently a footprint increment.

[0362] In one embodiment, in order to provide a baseline for the filtered TD-CRI, the sensing algorithm 558 requires a version of the sensing footprint. In one example, the sensing footprint can be delivered by a management frame, and in one example, a message type representing a sensing footprint transmission message can be defined.

[0363] In one example, the filtered TD-CRI may be delivered by a management frame. In one example, a message type may be defined to represent a delta-CRI message.

[0364] Fig. 22 An example of components of a management frame 1300 carrying a CRI transmission message according to some embodiments is shown. In one example, the system 500 may require an acknowledgment frame and the management frame carrying the CRI transmission message may be implemented as an action frame, and in another example, the system 500 may not require an acknowledgment frame and the management frame carrying the CRI transmission message may be implemented as an action No Ack frame.

[0365] In an example, the DeltaCRI message element conveys the TD-CRI using a bit field to represent the active (included / selected) time domain pulses, taking into account the DC tone and guard tones. Other examples of data representation were described earlier, and in examples, the DeltaCRI message element can be adjusted to reflect those data schemes.

[0366] In one example, the sensing footprint transfer message element transfers the sensing footprint from the sensing receiver 502-1 to the sensing algorithm 558 or the sensing transmitter 504-1 including the sensing algorithm 558. In one example, the data structure can be passed through the sensing footprint transfer message element, or the data structure can be compressed using any available lossless compression technique before transmission. In one example, the data describing the sensing footprint is accompanied by a header that describes the format of the data and the device and configuration with which the data is associated.

[0367] In one embodiment, when the sensing algorithm 558 is implemented on a separate device (i.e., not implemented within the sensing transmitter 504-1), management frames may not be necessary, and the sensing footprint and TD-CRI may be encapsulated in a standard IEEE 802.11 data frame and passed to the sensing algorithm 558. In one example, a proprietary header or descriptor may be added to the data structure to allow the sensing algorithm 558 to detect that the data structure is in the form of a sensing footprint transmission message element or a delta-CRI message element. In one example, the data may be transmitted in the form of a sensing footprint transmission message element or a delta-CRI message element. Fig. 22 The format shown is passed, and the sensing algorithm 558 can be configured to interpret the message type values ​​representing the sensing imprint transmission message element and the incremental CRI message element.

[0368] C. System and method for selecting and updating a set of detection devices

[0369] The present disclosure generally relates to systems and methods for Wi-Fi sensing. Specifically, the present disclosure relates to systems and methods for selecting and updating a set of probe devices, adapting the selection of a set of probe devices according to network utilization, and selecting sensing devices using physical parameters of a link.

[0370] A Wi-Fi sensing system may be configured to detect features of interest in a sensing space. A Wi-Fi sensing system may be a network of Wi-Fi enabled devices that is part of an IEEE 802.11 network, sometimes referred to as a basic service set (BSS) or an extended service set (ESS). Features of interest may include motion and movement tracking of objects, presence detection, intrusion detection, gesture recognition, fall detection, breathing rate detection, and other applications. A sensing space may refer to any physical space in which a Wi-Fi sensing system may operate, and may include a residence, a workplace, a shopping mall, a gymnasium or stadium, a garden, or any other physical space.

[0371] Currently, IEEE 802.11 physical channels consist of multiple orthogonal frequency division multiplexing (OFDM) tones or carriers depending on the total bandwidth of the channel and the revision of the specification. For example, 52 data and pilot carriers can be used for a 20 MHz channel bandwidth, and 104 data and pilot carriers can be used for a 40 MHz channel bandwidth. The baseband Wi-Fi receiver can calculate a sensing measurement (e.g., a channel state measurement (CSI)) consisting of a real part and an imaginary part for each element, and the sensing measurement can be passed to a sensing algorithm to determine whether there is motion or movement in the sensing space. In an example, the motion in the sensing space can be determined by the sensing algorithm by looking for disturbances in the local environment (e.g., on a transmission path (link) between one or more transmitter devices (e.g., a sensing transmitter) and one or more receiver devices (e.g., a sensing receiver)).

[0372] In an example, a BSS or ESS constituting a Wi-Fi sensing network in a sensing space may include multiple sensing-capable devices. In one example, with the popularity of the Internet of Things, a large number of sensing-capable devices supporting Wi-Fi may exist in various areas of a home. In one example, detecting motion in a sensing space requires sending sensing transmissions between devices with Wi-Fi sensing capabilities and performing sensing measurements on received sensing transmissions (which may be referred to as detection). In addition, devices with Wi-Fi sensing capabilities that participate in performing sensing transmissions may be referred to as detection devices. Typically, detecting the sensing space between paired Wi-Fi sensing-capable devices may take time because some or all detections may occur sequentially rather than in parallel. In addition, detection using dedicated sensing transmissions (e.g., sensing NDPs) requires bandwidth available for sensing transmissions, which may not be the case in congested networks. Therefore, there is a need for a method for selecting a subset of Wi-Fi sensing devices required for comprehensive detection of a sensing space in a Wi-Fi sensing network.

[0373] In a Wi-Fi sensing system, motion in a sensing space can cause interference on one or more links (transmission paths) between one or more sensing transmitters and one or more sensing receivers simultaneously. If some links have a large amount of coverage overlap, one of the links can be selected to sense the overlapping coverage area in the sensing space. The present disclosure describes a solution to determine which links are necessary links for sensing the sensing space and which links can be removed or fine-tuned by analyzing interference on the links.

[0374] In a Wi-Fi sensing system, there may be multiple sensing-capable devices communicating with an access point. In an example, all or some of the multiple sensing-capable devices may be used for Wi-Fi sensing. In an embodiment, the access point may be a sensing transmitter (e.g., sensing transmitter 504-1), and the multiple sensing-capable devices may be multiple sensing receivers (e.g., multiple sensing receivers 502-(1-M)). According to an implementation, the access point (e.g., sensing transmitter 504-1) may send a sensing advertisement message followed by a sensing null data PPDU (NDP) to a sensing-capable device (e.g., sensing receiver 502-1) of the multiple sensing-capable devices (e.g., multiple sensing receivers 502-(1-M)). The sensing-capable device (e.g., sensing receiver 502-1) may perform sensing measurements. In addition, the access point (e.g., the sensing transmitter 504-1) may send a sensing measurement polling message to a sensing-capable device (e.g., the sensing receiver 502-1) to trigger the sensing-capable device to send sensing measurement results back to the access point (e.g., the sensing transmitter 504-1). According to some embodiments, the access point may be a sensing receiver (e.g., the sensing receiver 502-1), and the multiple sensing-capable devices may be multiple sensing transmitters (e.g., multiple sensing transmitters 504-(1-N)). According to one implementation, the access point (e.g., the sensing receiver 502-1) may send a sensing trigger frame to a sensing-capable device (e.g., the sensing transmitter 504-1) among the multiple sensing transmitters (e.g., the multiple sensing transmitters 504-(1-N)). In this scenario, the sensing-capable device (e.g., the sensing transmitter 504-1) may perform a sensing transmission, and the access point (e.g., the sensing receiver 502-1) may perform sensing measurements on the sensing transmission. In Fig.11A , Fig. 11B and Fig.12 An example in which the access point and the one or more sensing-capable devices communicate with each other is explained in detail.

[0375] According to one embodiment, the connection between a sensing-capable device (hereinafter referred to as "device") and an access point may be referred to as a link and may be represented as "Ln", where "n" is defined as a link number. For example, the link number of L1 is 1, and the link number of L2 is 2. In one example, the link may be a sensing link that may be used for sensing transmission. In some examples, the link may be a data link that may be used for data transmission. In some examples, the link may be both a data link and a sensing link. A link combination may include two or more links having similar coverage in a sensing space and may be interchangeably used to sense motion in the sensing space. There may be several link combinations in the sensing space. In addition, there may be an area referred to as a sensing coverage area, in which motion may be detected by sensing transmission between a sensing-capable device and an access point. In some scenarios, motion in the sensing space may cause interference on multiple links at the same time. If some links have a large number of overlapping coverage areas, one or more links may be selected to sense the overlapping coverage areas in the sensing space. In one example, the one or more links selected for sensing the overlapping coverage areas may be referred to as sensing links. A sensing link may be used to detect a sensing space over a period of time. In an example, during the selection of a sensing link, one or more feasible, implementable, or non-essential links may be fine-tuned (i.e., not selected for sensing). In an example, the one or more links that are fine-tuned may be referred to as fine-tuning links. Examples of determining sensing links and fine-tuning links are described in detail below.

[0376] In a Wi-Fi sensing system, data transmission or sensing transmission may occur at different transmission opportunities (TXOPs) on a link. In an example, a Wi-Fi sensing system may utilize an orthogonal frequency division multiple access (OFDMA) TXOP not used for data transmission for Wi-Fi sensing.

[0377] Fig.26 An example representation 2600 of overlapping coverage areas in a Wi-Fi sensing system (e.g., system 500) is depicted in accordance with some embodiments. Fig.26 As shown, the Wi-Fi sensing system includes an access point 2602 and two devices with sensing capabilities (hereinafter referred to as "devices"), namely a first device 2604-1 and a second device 2604-2. Fig.26 , two links (depicted by dashed lines) are shown between the access point 2602 and two devices (i.e., the first device 2604-1 and the second device 2604-2). In the example, L1 represents the link between the access point 2602 and the first device 2604-1, and L2 represents the link between the access point 2602 and the second device 2604-2. Fig.26Further shown is coverage area 1 of the first device 2604-1 (indicated by reference numeral 2606) and coverage area 2 of the second device 2604-2 (indicated by reference numeral 2608). In addition, there is a large overlapping coverage area of ​​coverage area 1 and coverage area 2 (indicated by reference numeral 2610). Fig.26 Three motions are also shown, referred to as m1, m2, and m3. Motion m1 occurs only in coverage area 1, motion m2 occurs only in coverage area 2, and motion m3 occurs in the overlapping coverage area of ​​coverage area 1 and coverage area 2. In an example, motion m3 can be detected by link L1 or link L2. In order to simplify the sensing measurement process and reduce the number of sensing devices required for the sensing measurement process, either link L1 or L2 may be required. In an example, if link L1 is retained for sensing while link L2 is removed, link L1 may not detect motion m2 because it does not occur in coverage area 1. However, the portion of coverage area 2 that is not located in the overlapping coverage area of ​​coverage area 1 and coverage area 2 may be very small, so motions such as m2 that are only in coverage area 2 may be very small, and therefore, the removal of link L2 may be acceptable to the Wi-Fi sensing system. Therefore, link L1 can be selected as a sensing link, and link L2 can be fine-tuned, that is, not selected as a sensing link.

[0378] As can be inferred from the above, for Wi-Fi sensing purposes (e.g., motion detection or positioning), not all links within a link combination are necessary due to coverage overlap. Sensing on the links with all sensing-capable devices requires time, processing power, and bandwidth. Therefore, there is a need to fine-tune the links down to only those links that are critical for effectively detecting motion in the sensing space. Specifically, there is a need for a method for selecting sensing links within a link combination based on physical (PHY) layer criteria. The present disclosure describes a solution for determining which sensing links should be selected to effectively detect movement in the sensing space with the least number of sensing-capable devices.

[0379] Examples of determining links that are necessary links for sensing a sensing space and links that may be fine-tuned are described in detail below. In examples where two or more sensing links are within a link combination, the links may be fine-tuned based on PHY layer criteria.

[0380] According to one embodiment, an access point (which may be a sensing initiator) may be configured to discover or identify a candidate set of the plurality of networked devices. In one instance, the plurality of networked devices may include a plurality of sensing-capable devices to support Wi-Fi sensing. Additionally, in one instance, the candidate set may include a plurality of candidate devices that are capable of establishing a transmission link with the access point. In an instance, the plurality of candidate devices may include one or more sensing-capable devices from a plurality of sensing-capable devices. According to one instance, a candidate set may refer to a discovered set of sensing-capable devices that are not currently part of a sensing link set. Additionally, individual sensing-capable devices in the candidate set may be referred to as candidate devices. According to an example implementation, the access point may use Fig. 9 The multiple candidate devices are identified by the procedure described in. For example, the access point can determine the existence of the multiple candidate devices by sending a setup request (SENS measurement setup request frame), and the multiple candidate devices can respond to the setup request with a SENS measurement setup response frame. In an example, the access point can also check the availability of each candidate device to participate in the sensing session by sending a sensing poll (SENS Poll frame), and the available candidate devices can respond to the sensing poll with a CTS-to-self frame. Therefore, the access point can know the multiple candidate devices that can establish a transmission link or a sensing link with the access point.

[0381] According to one embodiment, the access point may be configured to establish multiple candidate sensing links between the multiple candidate devices and the access point (eg, for initiating a sensing session). In an example, the access point may be based on Figure 6 The WLAN sensing procedure (also referred to as Wi-Fi sensing procedure) described in the specification establishes the plurality of candidate sensing links between the plurality of candidate devices and the access point. Figure 6, describes a scenario in which an access point performs simultaneous Wi-Fi sensing with three candidate devices (e.g., a first device, a second device, and a third device). In an example, initially, a sensing session establishment procedure may be performed between the access point and the first device (sensing transmitter 504-1), the sensing session establishment procedure establishing a sensing session identified by the AID (AID 1) of the sensing transmitter 504-1. In addition, when the access point and the first device still have an active sensing session, a new sensing session establishment procedure may be performed between the access point and the second device, the new sensing session establishment procedure establishing a sensing session identified by the UID (UID 2) of the second device. In addition, when the access point and the second device still have an active sensing session, a new sensing session establishment procedure may be performed between the access point and the third device, the new sensing session establishment procedure establishing a sensing session identified by the AID (AID 3) of the third device. In this way, each device has a different sensing session establishment. In one embodiment, after the multiple links are established between the multiple devices and the access point, the access point may select one or more links from the multiple links as sensing links and fine-tune the remaining links.

[0382] Additionally, according to an embodiment, the access point may be configured to monitor sensing transmissions sent over the plurality of candidate sensing links during an analysis period.In an embodiment, the access point may identify a plurality of power changes based on received power in the plurality of candidate sensing links based on the sensing transmissions.

[0383] Fig. 27 An example 2700 of a Wi-Fi sensing system (eg, system 500) including multiple candidate devices is depicted in accordance with some embodiments. Fig. 27 As shown, the Wi-Fi sensing system includes an access point 2702 and six devices, namely a first device 2704-1, a second device 2704-2, a third device 2704-3, a fourth device 2704-4, a fifth device 2704-5 and a sixth device 2704-6. In addition, Fig. 27 Two reflectors are shown, referred to as first reflector 2706-1 and second reflector 2706-2. Fig. 27, six links (depicted by dashed lines) are shown between the access point 2702 and six devices (i.e., the first device 2704-1, the second device 2704-2, the third device 2704-3, the fourth device 2704-4, the fifth device 2704-5, and the sixth device 2704-6). In the example, L1 represents the link between the access point 2702 and the first device 2704-1, L2 represents the link between the access point 2702 and the second device 2704-2, L3 represents the link between the access point 2702 and the third device 2704-3, L4 represents the link between the access point 2702 and the fourth device 2704-4, L5 represents the link between the access point 2702 and the fifth device 2704-5, and L6 represents the link between the access point 2702 and the sixth device 2704-6. In an example, each of the links L1 , L2 , L3 , L4 , L5 , and L6 may be a candidate sensing link that may be selected as a sensing link or fine-tuned to not be a sensing link.

[0384] According to one embodiment, the access point may be configured to monitor the sensing transmissions sent through the multiple candidate sensing links. In one embodiment, the access point may be configured to determine the average power of the sensing transmissions within an analysis period. In one example, the analysis period may be one hour, half a day, one day, etc. In an example, each of the sensing transmissions sent through the multiple candidate sensing links is received at the access point with a received power. The power received from the multiple candidate sensing links at the sampling instance (s) at the access point may be defined as P1(s) of link L1, P2(s) of link L2, ..., Pn(s) of link Ln.

[0385] In one embodiment, the access point can identify multiple power changes based on the power received from the multiple candidate sensing links. In one instance, each power change can be characterized by a grouping of one or more candidate sensing links, and the grouping of the one or more candidate sensing links shows the change in received power compared to the average power of the sensing transmission of the corresponding candidate sensing link for one or more sampling instances (s) during the analysis period. In an example, the power change from one or more sampling instances (s) can be defined as p1(s) ​​of link L1, p2(s) of link L2, ..., pn(s) of link Ln. According to one embodiment, if the motion affects the received power of multiple candidate sensing links at the same sampling instance (s), the affected received power can be marked as the power change of the link combination of these candidate sensing links. In one instance, the power change of a single candidate sensing link can have a grouping containing only one candidate sensing link. In addition, the power change of the link combination can have a grouping of each candidate sensing link containing the link combination. In one example, if the motion affects the received power of both links L1 and L2 at the same sampling instance (s), it can be noted as the power change of the link combination of L1 and L2 (ie, p1p2(s)).

[0386] According to one embodiment, the access point may be configured to create a power change sequence of links and / or link combinations at different sampling instances (s1, s2, s3, ...) within the analysis period. In an example embodiment, the access point may store the power change sequence of links and / or link combinations in the power change information storage device 562 for future use. In an example, the power change sequence of links and / or link combinations at eleven (11) sampling instances (s1, s2, s3, ..., s11) is shown in Table 1 provided below. In addition, during the sampling instance from s1 to s11 as shown in Table 1, the combined intra-counter of each link is listed in Table 2 provided below.

[0387] Table 1: Power variation of links and / or link combinations over eleven (11) sampling instances

[0388] Sampling Examples Power variation of a link or combination of links Combo or Not Change Counter String Counter s1 p1 N 1 1 s2 p1p2 Y 1 1 s3 p1p2 Y 2 2 s4 p1p2 Y 3 3 s5 p2p3 Y 1 1 s6 p1p2 Y 4 1 s7 p1p2 Y 5 2 s8 p3p4p5 Y 1 1 s9 p3p4p5 Y 2 2 s10 p3p4p5 Y 3 3 s11 p6 N 1 1

[0389] Table 2: Combined intra-counters per link

[0390] link Combination internal counter L1 5 L2 6 L3 4 L4 3 L5 3 L6 0

[0391] In the example of Table 1, the parameter "Combo or Not" indicates whether the power change affects a single link (Not) or more than one link (Combo). For example, as shown in Table 1, for the link combination "p1p2", the power change affects links L1 and L2 (i.e., more than one link). Therefore, the value of the parameter "Combo or Not" of the link combination "p1p2" is yes (Y). In addition, the parameter "Change Counter" indicates the number of occurrences of a specific power change of a link or link combination during all sampling instances in the analysis cycle. In the example, each time a power change of a link or link combination occurs, the change counter of the power change of the link or link combination will increase by 1. In addition, the parameter "String Counter" indicates the number of times a power change of a link or link combination occurs within a string. In an example, if a power change of a link or link combination occurs once within a string, the string counter will increase by 1. In some examples, if the power change of a link or link combination changes at the next sampling instance, the string counter of the power change of the link or link combination will be reset to zero. In the example of Table 2, the parameter "Counter within combination" for a link can be defined as the number of times the link appears in all power changes of the link combination during all sampling instances in the analysis period. For example, as shown in Table 2, the value of the parameter "Counter within combination" for link L5 is 5 because link L5 appears 5 times in all power changes of the link combination during eleven (11) sampling instances in the analysis period. In one embodiment, each power change of a link or link combination can have several strings. For example, for the power changes of the link combination "p1p2" in Table 1, the string length of the first string of p1p2 (covering sampling instances s1, s2, and s3) is 3, and the string length of the second string of p1p2 (covering sampling instances s6 and s7) is 2. Therefore, the maximum string length of p1p2 is 3. In addition, the frequency of the power changes of the link combination is determined by the change counter. In one example, the most frequent power change of the link combination has the largest change counter.

[0392] According to an embodiment, the access point may be configured to identify a sensing link set according to a sensing transmission. In an example, the sensing link set may include a plurality of selected sensing links selected from the plurality of candidate sensing links. According to an embodiment, the access point may be configured to analyze the plurality of power changes to identify the sensing link set. In an embodiment, the access point may analyze the power changes of the link combination so as to remove unnecessary links and retain a single necessary link in the sensing link set to represent the power changes of the link combination. According to an embodiment, the access point may determine the order in which the different power changes of the link combination may be analyzed. In an example, the power changes of the link combination may be analyzed in the order of a change counter, a maximum string length, or a combination length. In an example, the order in which the different power changes of the link combination are analyzed may be referred to as an importance level. For example, the importance level may be determined according to at least one of the combination length representing the number of candidate sensing links that appear in a plurality of power changes, the change counter representing the number of occurrences of each power change from the plurality of power changes, and the maximum string length representing the maximum number of consecutive occurrences of each power change from the plurality of power changes. The power change list of the link combination in the order of the change counter is described as the importance level in Table 3 provided below.

[0393] Table 3: List of power changes of link combinations in order of change counters as importance level

[0394]

[0395]

[0396] In the example of Table 3, the parameter "combination length" indicates the number of links in the power variation of the link combination. For example, as shown in Table 3, the value of the parameter "combination length" of the link combination "p3p4p5" is 3.

[0397] According to one embodiment, the access point may be configured to identify a sensing link set according to a sensing space coverage metric. In one embodiment, the access point may determine a power variation test set containing a subset of power variations selected from the multiple power variations for analysis by the sensing space coverage metric. In an example, the power variation test set may be defined as a group of power variations selected from a combination of links of the multiple power variations for analysis to determine which links are selected as sensing links. According to the power variation test set, the access point may select a first power variation from the multiple power variations according to the importance level of the multiple power variations. In addition, the access point may select a second power variation that does not have a candidate sensing link in common with the first power variation from the remaining power variations in the multiple power variations according to the importance level of the remaining power variations in the multiple power variations. In an example, the power variation test set may include a first power variation and a second power variation. In one embodiment, the power variation test set may further include one or more additional power variations so that each candidate sensing link appears only in a group from the first power variation, the second power variation, and the one or more additional power variations. According to some embodiments, the power variation test set may include a single power variation.

[0398] In an example embodiment, the access point may analyze the multiple power changes of the link combinations in order of combination length as the importance level for identifying the sensing link set. The analysis of the power changes of the link combinations in order of combination length as the importance level is described in Table 4 provided below.

[0399] Table 4: Analysis of power variation of link combinations in order of combination length as importance level

[0400]

[0401] In the example of Table 4, the parameter "whether selected" indicates whether the power variation of the link combination is selected for analysis as a member of the power variation test set. In one example, the parameter "cover all combined links" indicates whether all combined links are included in the selected power variation of the link combination. Once all combined links are covered, no further power variations of the link combination are analyzed.

[0402] In the example, in Table 4, the power variation of the link combination "p3p4p5" with the maximum combined length (i.e., three) is first selected. The next power variation of the link combination "p1p2" is selected because the link combination has the next maximum combined length (i.e., two) in the unselected combination (e.g., p1p2, p2p3, ...) and the link combination does not contain any previously selected combined links. As shown in Table 4, since link L3 (or p3) has been included in the selected power variation of the link combination "p3p4p5", the power variation of the link combination "p2p3" is not selected. In the example, after the second selection, all combined links (e.g., L1, L2, L3, L4, and L5) are included in the selected power variation of the link combination (e.g., "p3p4p5" and "p1p2"), so the selection is completed. Therefore, the power variation test set contains the first power variation (i.e., "p3p4p5") and the second power variation (i.e., "p1p2").

[0403] According to one embodiment, once a power variation test set is determined, the access point may be configured to determine a power ratio parameter (R ) for a test power variation in the power variation test set. combo ). In one example, the power ratio parameter may represent a ratio of a parameter of the power variation of the link combination (e.g., maximum string length, variation counter, etc.) to a corresponding parameter of a single link power variation of one of the candidate sensing links of the link combination power variation. In one example, a single link power variation may refer to a power variation associated with one of the candidate sensing links of the grouping of power variations that occurs in the absence of other candidate sensing links of the grouping. For example, the candidate sensing links L2, L3, and L4 of the power variation represented by the grouping p2p3p4 may have associated single link power variations p2, p3, and p4, respectively.

[0404] In one embodiment, the access point may determine the power ratio parameter (R) by dividing the first maximum burst length by the second maximum burst length. combo ), the first maximum string length represents the maximum consecutive number of occurrences of the test power change from the power change test set in the analysis period, and the second maximum string length represents the maximum consecutive number of occurrences of the single link power change associated with each candidate sensing link of the group of the test power change in the analysis period. The power ratio parameter (R) determined based on the parameter "maximum string length" combo ) is expressed in equation (9) as follows:

[0405]

[0406] For example,

[0407]

[0408] In some embodiments, the access point may determine a power ratio parameter (R ) based on dividing the first change counter by the second change counter. combo ), the first change counter represents the number of occurrences of the test power changes from the power change test set in the analysis period, and the second change counter represents the maximum number of occurrences of the single link power changes associated with each candidate sensing link of the group of the test power changes in the analysis period. The power ratio parameter (R) determined based on the parameter "change counter" combo ) is expressed in equation (10) as follows:

[0409]

[0410] For example,

[0411]

[0412] According to one embodiment, the access point may determine an additional power ratio parameter for additional power changes of the power change test set. In addition, the access point may compare the additional power ratio parameter with a ratio threshold factor (r) for each of the additional power changes. th In one embodiment, the access point may compare the ratio of the access point to the access point having a ratio factor exceeding the threshold factor (r th ), selecting, from each grouping of the additional power changes, additional selected candidate sensing links for inclusion in the sensing link set based on the candidate sensing links that appear in a maximum number of the plurality of power changes.

[0413] According to one embodiment, in determining a power ratio parameter (R) for a test power variation in a power variation test set, combo ), the access point can be configured to set the power ratio parameter (R combo ) and the ratio threshold factor (r th ) is compared. In an example, a ratio threshold factor (r) may be defined for equation (9) or equation (10) th ), where the ratio threshold factor (r th ) is the minimum power ratio parameter (R combo In one embodiment, the ratio threshold factor (r th In one example, the ratio threshold factor (r th ) can have a value of 5. This indicates that if the coverage area of ​​the power variation of the link combination is five times the coverage area of ​​each combined link of the power variation of the link combination, then one or more links can be removed from the power variation of the link combination. In the example, if the ratio threshold factor (rth ) is too low, removing the link may result in less accurate motion detection. In one embodiment, the access point may optimize the ratio threshold factor (r) over time based on successful motion detection. th ). In this example, the ratio threshold factor (rh) needs to be increased until the best motion detection success rate is achieved.

[0414] According to one embodiment, the access point may respond to the power ratio parameter (R combo ) exceeds the ratio threshold factor (r th ), select the selected candidate sensing link from the test power variation group according to the candidate sensing link appearing in the largest number of the plurality of power variation groups to be included in the sensing link set. Referring to Table 4, the parameter "above ratio threshold factor (rh)" indicates the power ratio parameter (R) of the power variation of the link combination. combo ) (e.g., as calculated using equation (9)) is greater than the ratio threshold factor (r th In this example, if the power ratio parameter (R combo ) is greater than the ratio threshold factor (rh), there may be significant overlap between the links in the power variation of the link combination. For example, as shown in Table 4, for the power variation of the link combination "p3p4p5", the power ratio parameter (R combo ) is greater than the ratio threshold factor (r th ). Therefore, there may be significant overlap between links L3, L4, and L5. In an example, within this power variation of link combination "p3p4p5", the link with the largest intra-combination counter (i.e., link L3) may represent the power variation of link combination "p3p4p5" and may be added to the sensed link set, while the other links (i.e., links L4 and L5) are removed.

[0415] In one embodiment, the access point may retain links that are not represented in any power change of the link combination. In one example, the retained links are sensing links. In the example of Table 1, link L6 is not represented in any power change of the link combination.

[0416] In an example, a link may be selected as a sensing link within a link combination if it has the largest "in-combination counter" among all links within the link combination. Other links within the link combination may be fine-tuned. In an example, a first link combination may include links L1 and L2, and a second link combination may include links L3, L4, and L5.

[0417] Table 5 provided below shows the necessary links from the above example. In the example, the necessary links can form a sensing link set that can be used to measure the sensing space. In one embodiment, in the example of Table 5, within the link combination including links L1 and L2, link L2 is selected as the sensing link because link L2 has the largest intra-combination counter and link L1 is fine-tuned. Similarly, within the link combination including links L3, L4 and L5, link L3 is selected as the sensing link because link L3 has the largest intra-combination counter, while the other links L4 and L5 within the link combination are fine-tuned. In addition, link L6 may not be part of the link combination, and therefore link L6 is also maintained as a sensing link.

[0418] Table 5: Necessary links

[0419] link Combination internal counter Remove Necessary links L1 5 Y N L2 6 N Y L3 4 N Y L4 3 Y N L5 3 Y N L6 0 N Y

[0420] In one embodiment, after identifying the sensing link set, the access point can establish a plurality of sensing sessions for the sensing links in the sensing link set for motion detection purposes. In an example, the access point can establish the plurality of selected sensing links between selected devices from the plurality of candidate devices (e.g., one or more sensing-capable devices from the plurality of sensing-capable devices and the access point).

[0421] In one embodiment, after the plurality of links are established between the plurality of devices and the access point, the access point may select one or more links among the plurality of links as sensing links and fine-tune the remaining links.

[0422] From About Fig. 27 The described example continues, Fig.28 Depicted are example representations of the same multiple links in a sensing space in accordance with some embodiments.

[0423] exist Fig.28 In the embodiment, three links, such as links L2, L3 and L6, are selected as sensing links, as shown in solid lines. In one example, the set of sensing links may be referred to as a sensing link set. Referring to the above example, the sensing link set includes links L2, L3 and L6 corresponding to the selected second device 2804-2, the third device 2804-3 and the sixth device 2804-6, respectively. Although other known examples and embodiments of determining a sensing link set are considered herein, these examples and embodiments need not be fully described in the present disclosure.

[0424] In one embodiment, after determining (or identifying) the sensing link set by fine-tuning away non-essential links, the sensing space may change. In one instance, the change in the sensing space may be caused by an object in the sensing space moving from its original position to a new position. For example, a reflector in the sensing space may move from its original position to a new position. In an example, a change in the sensing space or the addition of a new device in the sensing space may change the sensing link set. In some scenarios, some devices that are part of the sensing link set may no longer be suitable (or useful) for sensing and should be removed.

[0425] In some scenarios, after sensing links have been selected, one or more of the sensing links may become congested, leaving little available bandwidth for sensing measurement exchange. As a result, the ability of the Wi-Fi sensing system to effectively probe the sensing space may be impaired. Therefore, a method is needed for detecting congestion conditions that impair sensing of the sensing space and replacing the sensing links with fine-tuned links without losing sensing fidelity.

[0426] In addition, in an example, the multiple candidate sensing links may include original sensing links in a previously established sensing link set (also referred to as an original sensing link set) and fine-tuning sensing links that are not included in the previously established sensing link set. In an example, each power change may have at least one original sensing link. According to an embodiment, the access point may access previously stored sensing detection information. In an example, the access point may obtain or retrieve sensing detection information from the sensing information storage device 562. In some embodiments, in order to obtain the sensing detection information, the access point may be configured to establish multiple candidate sensing links between the multiple devices and the access point, such as with respect to Fig. 27 In an example, the access point can be based on Figure 6 The WLAN sensing procedure (also referred to as Wi-Fi sensing procedure) described in the embodiment establishes the plurality of candidate sensing links between the plurality of devices and access points. Fig. 27 In the example shown in , the multiple devices may include six devices, referred to as a first device, a second device, a third device, a fourth device, a fifth device, and a sixth device. In addition, in an example, there may be six candidate sensing links between the access point and the device. The six candidate sensing links may include links L1, L2, L3, L4, L5, and L6. In an example, among links L1, L2, L3, L4, L5, and L6, links L2, L3, and L6 may be original sensing links, and links L1, L4, and L5 may be original fine-tuning sensing links. In addition, according to an embodiment, the access point may be configured to monitor sensing transmissions sent through the multiple candidate sensing links during an analysis period. In an embodiment, the access point may identify multiple power changes in the multiple candidate sensing links based on the sensing transmissions.

[0427] According to one embodiment, after obtaining the sensing detection information, the access point can be configured to determine a plurality of data usage values corresponding to the plurality of candidate sensing links. In one example, the data usage rate can indicate how many TXOPs are used for data transmission within X TXOPs. In an example, if a link is not used for data transmission during the relevant period, the data usage rate of the link can be zero. In an example, the data usage value of a link can be mathematically expressed as:

[0428] Data usage rate = (Number of TXOPs used for data transmission) / X...(11)

[0429] In one embodiment, the access point can use equation (11) to determine the plurality of data usage values corresponding to the plurality of candidate sensing links.

[0430] According to one embodiment, the access point can be configured to identify a set of sensing links based on a sensing space coverage metric determined from the sensing detection information and the plurality of data usage values. In an example, the set of sensing links can include a plurality of representative sensing links selected from the plurality of candidate sensing links. In one embodiment, the access point can determine a power change test set including a subset of power changes selected from the plurality of power changes for analysis through the sensing space coverage metric. In an example, the power change test set can be defined as a set of power changes of a link combination selected from the plurality of power changes for analysis to determine which links are selected as sensing links. Examples of identifying the set of sensing links are described in detail below.

[0431] In one embodiment, the access point can identify a congested sensing link among the original sensing links as having a corresponding data usage value exceeding a congestion threshold T from the plurality of data usage values. In an example, the congestion threshold T can indicate whether the data usage rate of a link is high or low. For example, for a link, if the data usage rate >= T (e.g., 90%), the link can be defined as a congested link. Similarly, for a link, if the data usage rate < T (e.g., 90%), the link can be defined as a non-congested link. In an example, during a TXOP not used for data transmission, a non-congested link can be used for sensing transmission. In an example, among the original sensing links L2, L3, and L6, the data usage value of link L3 may exceed the congestion threshold T. For example, the data usage value of link L3 can be 91%. Therefore, link L3 can be identified as a congested sensing link.

[0432] In one embodiment, when identifying a congestion sensing link, the access point may be configured to identify a power change corresponding to the congestion sensing link based on the above method. In addition, according to one embodiment, the access point may be configured to identify one or more fine-tuning sensing links that belong to a power change corresponding to the congestion sensing link. In one example, fine-tuning sensing links L4 and L5 may be identified as belonging to a power change corresponding to the congestion sensing link L3.

[0433] In one embodiment, the access point may select a representative sensing link for power variation from the congestion sensing link and the one or more fine-tuning sensing links. According to one embodiment, the access point may select a representative sensing link for power variation to balance the link loads in the sensing link set. In an example, the link load of a link may be mathematically represented as shown in Equation 12.

[0434] Link load = (number of TXOPs used for data transmission +

[0435] Number of TXOPs used for sensing transmission) / X…(12)

[0436] Wherein, “the number of TXOPs used for sensing transmission) / X” represents the sensing utilization rate of the link.

[0437] According to some embodiments, the access point may be configured to identify additional congestion sensing links from the original sensing links based on the multiple data usage values. In addition, the access point may be configured to identify additional power changes corresponding to the additional congestion sensing links. The access point is further configured to identify additional sets of one or more fine-tuning sensing links belonging to the additional power changes. For each additional power change, the access point may be configured to select a corresponding representative sensing link from the corresponding additional congestion sensing link and the corresponding additional set of one or more fine-tuning sensing links.

[0438] In an example embodiment, the access point may select a fine tuning sensing link (from the one or more fine tuning sensing links) that appears in a plurality of groups characterizing a maximum number of the plurality of power changes as a representative sensing link. In other words, a fine tuning sensing link with a highest intra-combination counter among the one or more fine tuning sensing links of a link combination may be selected as a representative sensing link. In some example embodiments, the access point may select a fine tuning sensing link (from the one or more fine tuning sensing links) with a lowest data usage value among the plurality of data usage values ​​as a representative sensing link.

[0439] According to some embodiments, the access point may select a representative sensing link for power variation from the congestion sensing link and the one or more fine-tuning sensing links according to a switching factor defined for each of the congestion sensing link and the one or more fine-tuning sensing links. In an example, the switching factor may be defined as the number of occurrences of a link in the plurality of power variation groups divided by a data usage value corresponding to the link. The switching factor may be mathematically represented as shown in Equation 13.

[0440] Switching factor = (counter within combination) / (data usage %) ... (13)

[0441] In one embodiment, the power change may include a congestion sensing link and a non-congestion fine-tuning sensing link. According to one embodiment, the access point may select a representative sensing link among the congestion sensing link and the non-congestion fine-tuning sensing link according to the highest switching factor. According to one embodiment, a switching action may occur between the congestion sensing link and the non-congestion fine-tuning sensing link according to the highest switching factor. In one example, the switching action may be defined as an action of switching the congestion sensing link to one of the multiple non-congestion fine-tuning sensing links within the same link combination. In an example embodiment, if the sensing link coincides with the congestion link and the other fine-tuning sensing links are also on the congestion link, the switching action may not occur. In one example, if the non-congestion fine-tuning sensing link has the highest switching factor, the access point may select the non-congestion fine-tuning sensing link as the representative sensing link. This means that the congestion sensing link (congested original sensing link) can be switched to the non-congestion fine-tuning sensing link (that is, the congestion sensing link can be replaced by the non-congestion fine-tuning sensing link). Therefore, the non-congestion fine-tuning sensing link is an updated sensing link.

[0442] Fig.29 The updated sensing link is shown in Fig.29 , a Wi-Fi sensing system including multiple candidate devices according to some embodiments is shown (e.g., Fig. 27 500 as shown in FIG. Fig.29 As shown, the Wi-Fi sensing system includes an access point 2902 and six devices, namely a first device 2904-1, a second device 2904-2, a third device 2904-3, a fourth device 2904-4, a fifth device 2904-5 and a sixth device 2904-6. Fig.29 Two reflectors are shown, referred to as first reflector 2906-1 and second reflector 2906-2. Fig.29, six links (depicted by dashed lines) are shown between the access point 2902 and six devices (i.e., the first device 2904-1, the second device 2904-2, the third device 2904-3, the fourth device 2904-4, the fifth device 2904-5, and the sixth device 2904-6). In the example, L1 represents the link between the access point 2902 and the first device 2904-1, L2 represents the link between the access point 2902 and the second device 2904-2, L3 represents the link between the access point 2902 and the third device 2904-3, L4 represents the link between the access point 2902 and the fourth device 2904-4, L5 represents the link between the access point 2902 and the fifth device 2904-5, and L6 represents the link between the access point 2902 and the sixth device 2904-6. In the example, each of the links L1, L2, L3, L4, L5, and L6 is a candidate sensing link.

[0443] An example of updated sensing links is described in Table 6 provided below. The solid lines on L2, L4 and L6 represent updated sensing links after a switching action occurs.

[0444] Table 6: Updated sensing links

[0445]

[0446] In the example of Table 6, in the link combination including links L3, L4, and L5, link L3 is a congestion sensing link (original sensing link) having a data usage value of 91%, link L4 is a non-congestion fine-tuning sensing link having a data usage value of 60%, and link L5 is a congestion fine-tuning sensing link having a data usage value of 95%. In addition, as shown in Table 6, the switching factor of link L3 is 4.40, and the switching factor of link L4 is 5.00. Since the switching factor of link L4 is higher than the switching factor of link L3, a switching action may occur between link L3 and link L4. Therefore, link L4 is an updated sensing link.

[0447] Other examples of updated sensing links are described in Table 7 provided below.

[0448] Table 7: Updated sensing links

[0449]

[0450] In the example of Table 7, in the link combination including links L3, L4, and L5, link L3 is a congestion sensing link (congested original sensing link) having a data usage value of 91%, link L4 is a non-congestion fine-tuning sensing link having a data usage value of 60%, and link L5 is a congestion fine-tuning sensing link having a data usage value of 95%. In addition, in the example shown in Table 7, the switching factor of link L3 is 4.40, and the switching factor of link L4 is 3.75. Since the switching factor of link L4 is not higher than the switching factor of link L3, the switching action between link L3 and link L4 may not occur, and the updated sensing link is the same as the original sensing link.

[0451] In some embodiments, the power variation may include a congestion sensing link and a plurality of non-congestion fine-tuning sensing links. According to one embodiment, the access point may select a representative sensing link from the congestion sensing link and the plurality of non-congestion fine-tuning sensing links according to the highest switching factor. In some embodiments, the access point may further select a representative sensing link from two non-congestion fine-tuning sensing links having the same switching factor according to a non-congestion fine-tuning sensing link having a lower link number.

[0452] In one example, if the congestion sensing link and one of the plurality of non-congestion fine-tuning sensing links are present in the same link combination, a switching action may occur between the congestion sensing link and one of the plurality of non-congestion fine-tuning sensing links. In some examples, if the switching factor of one of the plurality of non-congestion fine-tuning sensing links is higher than that of the congestion sensing link, a switching action may occur between the congestion sensing link and the non-congestion fine-tuning sensing link having the higher switching factor. In some examples, if the switching factor of one of the plurality of non-congestion fine-tuning sensing links is higher than that of the congestion sensing link and is also the highest among all non-congestion fine-tuning sensing links in the same link combination, a switching action may occur between the congestion sensing link and the non-congestion fine-tuning sensing link having the highest switching factor. In some examples, if the congestion sensing link and the plurality of non-congestion fine-tuning sensing links are present in the same link combination and two or more non-congestion fine-tuning sensing links have the same switching factor, a switching action may occur between the congestion sensing link and the non-congestion fine-tuning sensing link having a lower link number.

[0453] Other examples of updated sensing links are described in Table 8 provided below.

[0454] Table 8: Updated sensing links

[0455]

[0456] In the example of Table 8, within the link combination including links L3, L4, and L5, link L3 is a congestion sensing link (congested original sensing link) with a data usage value of 91%, link L4 is a non-congestion fine-tuning sensing link with a data usage value of 60%, and link L5 is a congestion fine-tuning sensing link with a data usage value of 60%. In addition, in the example shown in Table 8, the switching factor of link L3 is 4.40, the switching factor of link L4 is 5.00, and the switching factor of link L5 is also 5.00. Since the switching factors of link L4 and link L5 are the same and higher than the switching factor of link L3, and the link number of link L4 is less than the link number of link L5, a switching action may occur between link L3 and link L4. Therefore, the updated sensing link (or representative sensing link) is different from the original sensing link. It can be understood that after the switching action, the sensing link set is updated.

[0457] The updated sensing link (or representative sensing link) is different from the original sensing link. It can be understood that after the switching action, the sensing link set is updated. The updated sensing link set contains the updated sensing link. Fig.29 An updated sensing link is shown after a switching action occurs between link L3 and link L4. Fig.29 2 shows three updated sensing links (i.e., link L2, link L4, and link L6) identified after a switching action occurs between link L3 and link L4. Fig.29 As shown in the solid line. Fig.29 See (and with Fig.28 Compared with , the congested original sensing link L3 is replaced by the non-congested fine-tuning sensing link L4.

[0458] According to one embodiment, due to the switching action between link L3 and link L4, the link load between link L3 and link L4 is balanced. For example, before the switching action, the link load of link L3 = data usage + sensing usage (e.g., 5%) = 91% + 5% = 96%, and the link load of link L4 = data usage + sensing usage = 60% + 0 = 60%, so the link load between link L3 and link L4 is unbalanced (95% vs. 60%). However, after the switching action, the link load of link L3 = data usage + sensing usage = 91% + 0 = 91%, and the link load of link L4 = data usage + sensing usage = 60% + 5% = 65%, and the link load between L3 and L4 is more balanced than before (91% vs. 65%).

[0459] In one embodiment, the sensing link set identified by the access point (updated sensing link set) may include the multiple representative sensing links (e.g., links L2, L4, and L6) selected from the multiple candidate sensing links. According to one embodiment, the access point may be configured to establish the multiple representative sensing links between the corresponding devices in the multiple devices and the access point. According to one embodiment, the access point may establish multiple sensing sessions for the multiple representative sensing links in the sensing link set for motion detection purposes. In some embodiments, the sensing session may be measured at one or more sampling instances of the analysis period.

[0460] Fig.30 An example representation of multiple links in a sensing space according to some embodiments is depicted. Fig.30 In the example of Fig.29 ) to a new location. Fig.30 As shown, a new device (seventh device 3004-7) has been installed in the sensing space and is an idle device.

[0461] According to one embodiment, the access point may be configured to maintain a plurality of selected sensing links as a set of sensing links between selected devices of the plurality of devices and the access point. As previously described, after the sensing link set is established, changes may occur in the sensing space. In order to determine which devices to use to sense the changed sensing space, the access point may periodically check the sensing space to determine whether there are devices that are not currently part of the sensing link set but can be used to sense the changed sensing space. In some embodiments, the access point may be configured to determine the devices, for example, by association or by a discovery process as described previously. In an instance, the result of the discovery process causes the access point to know all devices that can form a sensing link with the access point. In one instance, reference Fig.30 , the discovered devices may include unselected devices (or fine-tuned devices) among the multiple devices (e.g., the first device 3004-1, the fourth device 3004-4, and the fifth device 3004-5) and / or new devices that have been installed in the sensing space (e.g., the seventh device 3004-7).

[0462] In one embodiment, the access point may be configured to identify multiple candidate links as a set of candidate links between unselected devices in the multiple devices and the access point. In one embodiment, the access point may identify a fine-tuning link that is not included in the sensing link set and include the fine-tuning link in the candidate link set as a candidate link. In some embodiments, the access point may include the discovered device as a candidate device in the candidate link set representing the candidate links. In an example, the candidate link set may include candidate links and / or fine-tuning links (already known to the access point but not currently part of the sensing link set) that can be established with the device discovered by the discovery process (where no sensing link existed prior to the analysis period).

[0463] Reference again Fig.30 , data links (depicted by solid lines) between the access point 3002 and six devices (i.e., the first device 3004-1, the second device 3004-2, the third device 3004-3, the fourth device 3004-4, the fifth device 3004-5, and the sixth device 3004-6) are ongoing. In addition, three links (e.g., link L2, link L3, and link L6 between the access point 3002 and the second device 3004-2, the third device 3004-3, and the sixth device 3004-6, respectively) are also sensing links (depicted by dotted lines) of the sensing link set. In the example, the data links and the sensing links (link L2, link L3, and link L6) are on different TXOPs. Reference Fig.30 The candidate link set may include devices that fine-tune the links (eg, a first device 3004-1 that fine-tunes link L1, a fourth device 3004-4 that fine-tunes link L4, and a fifth device 3004-5 that fine-tunes link L5) and an idle device (a seventh device 3004-7).

[0464] According to one embodiment, the access point can be configured to identify multiple evaluation links as the evaluation link set from the candidate link set and the original sensing link set within the analysis period (or analysis period). In one embodiment, the access point can select one or more sensing links in the multiple sensing links as the evaluation link. In some embodiments, the access point can select a subset of the multiple candidate links as the evaluation link. In an example, since the evaluation link set includes the sensing link set, there is continuity in the sensing of the sensing space. Table 9 provided below shows an example of an evaluation link.

[0465] Table 9: Evaluation links

[0466] link Original sensing link Evaluation Link L1 N N L2 Y Y L3 Y Y L4 N Y L5 N N L6 Y Y L7 N N

[0467] In the example of Table 9, sensing links L2, L3 and L6 are selected as evaluation links. In addition, fine-tuning link L4 is also selected as evaluation link.

[0468] According to some embodiments, the access point may be configured to determine whether the congestion metric of the access point is above a congestion threshold. In response to determining that the congestion metric of the access point is above the congestion threshold, the access point may select one or more active devices (fine-tuning devices) from the candidate devices in the candidate link set to be included in the evaluation link set. In an example, if the access point determines that its bandwidth is fully occupied, the access system may select one or more devices that are only involved in the established data link. These devices are referred to as active devices. Since the data link already has a negotiated bandwidth associated with it, additional bandwidth is not required. In one embodiment, the number of idle devices that can be added to the evaluation link set may depend on the overall congestion of the access point and / or the congestion of each data link in the ongoing data link.

[0469] In some embodiments, the access point may be configured to determine whether a congestion metric of the access point is below a congestion threshold. In response to determining that the congestion metric of the access point is below the congestion threshold, the access point may select one or more idle devices among the candidate devices in the candidate link set to include in the evaluation link set. In an example, if the access point determines that its bandwidth is not fully occupied, the access point may add the one or more idle devices to the evaluation link set using bandwidth allocations that are not yet occupied, optionally in addition to including one or more active devices among the candidate devices in the evaluation link set.

[0470] In an example, the congestion of an access point can be determined as a combination of the congestion of the access point's links, for example using the method described previously with respect to Fig.29 A measure of congestion of a data link as described and as described in Equation 11 is “data usage rate”.

[0471] In an example, the measure of the congestion of the sensing link may be a “sensing usage rate”. In an example, the sensing usage rate of the sensing link may be mathematically expressed as shown in Equation 14:

[0472] Sensing utilization rate = (number of TXOPs used for sensing transmission) / X (14)

[0473] In an example, for a link used for both data transmission and sensing transmission, a measure of congestion may be “link load.” In an example, link load may be mathematically represented as shown in Equation 15:

[0474] Link load = (number of TXOPs used for data transmission +

[0475] Number of TXOPs used for sensing transmission) / X…(15)

[0476] In one embodiment, the access point may calculate a measure of congestion as a combination of the congestion of the access point's links. In one example, the access point may calculate or determine congestion based on averaging the data usage, sensing usage, and link load usage of all links currently in use at the access point. In an example, the congestion of the access point may be determined using a congestion metric "AP link load". In one embodiment, the AP link load may be mathematically represented as shown in Equation 16:

[0477] AP link load = ∑ 所有链路 (The number of TXOPs used for data transmission

[0478] + the number of TXOPs used for sensing transmission) / X…(16)

[0479] In an example, the number of idle devices added to the evaluation link set can be a function of the AP congestion metric. In an example, the AP congestion metric can be normalized relative to a range of 0 to 100, where 0 means the access point is completely idle and 100 means every possible TXOP of the access point is used. In an example, thresholds (e.g., AP congestion thresholds) at which additional idle devices can be added to the evaluation link can be defined. Examples of these thresholds are shown in Table 10 provided below.

[0480] Table 10: Thresholds

[0481] AP congestion threshold The number of idle devices that can be added to the evaluation link set More than 80 none Between 60 and 80 Up to 2 Between 40 and 60 Up to 4 Below 40 The maximum value that can be supported depends on the available access point bandwidth.

[0482] According to one embodiment, once the evaluation link set is determined, the access point can be configured to determine the allocation of channel resources (i.e., transmission bandwidth) for the multiple evaluation links in the evaluation link set so as to establish the multiple evaluation links. In one embodiment, the access point can be configured to determine the allocation of channel resources for the device included in the evaluation link set. In an example embodiment, the access point can be configured to determine the allocation of channel resources for the selected device of the sensing link set included in the evaluation link set (i.e., the sensing device in the current sensing link set). In some example embodiments, the access point can be configured to determine the allocation of channel resources for the one or more active devices included in the evaluation link set. In some example embodiments, the access point can be configured to determine the allocation of channel resources for the one or more idle devices included in the evaluation link set. According to one embodiment, the access point can maintain the existing allocation of resource units (RUs) for the selected device and the one or more active devices included in the evaluation link set. In addition, in one embodiment, the access point can allocate RUs to the one or more idle devices included in the evaluation link set. In an example, for the evaluation link as the selected sensing link in the current sensing link set, the allocation of channel resources can remain unchanged during the analysis period. Additionally, in an example, for evaluation links that are not sensing links in the current sensing link set but are currently data links (i.e., fine-tuning links), the access point may use the channel resource allocation allocated for the data link (prior to establishing the analysis period) during the analysis period. Additionally, in an example, for idle devices added to the evaluation link set, the access point may determine an allocation of channel resources for the evaluation link established for each idle device. In an example, the allocation of channel resources may depend on different factors, including the available bandwidth of the access point, the number of idle devices added to the evaluation link set by the access point, and the resolution at which the access point attempts to establish an evaluation link with each idle device added to the evaluation link set (e.g., scanning mode versus detection mode.) In some examples, the access point may add as many idle devices as possible to the evaluation link set, for example, by assigning a small (or minimum) channel resource allocation to each idle device included in the evaluation link set.

[0483] In one embodiment, the access point can establish the multiple evaluation links according to the allocation of the analysis period. In some scenarios, there may be system changes during the analysis period, and the RU allocation for the evaluation link may need to be adjusted accordingly. In some embodiments, the access point can determine the reallocation of channel resources for the multiple evaluation links according to the change of the data link bandwidth on the multiple evaluation links during the analysis period. In an example, if the RU allocation of one or more data links for the access point changes during the analysis period, then for the evaluation link that is also a data link, the access point can continue to align the RU allocation for the evaluation with the RU allocation of the ongoing data link (that is, the evaluation link bandwidth is the same as the updated data link bandwidth). In some instances, if the RU allocation of one or more data links for the access point (regardless of whether they are evaluation links) increases during the analysis period, or if a new data link is established with a device that is not part of the evaluation link set, the access point may need to reduce the RU allocation of the evaluation link established with the idle device added to the evaluation link set, for example, within the duration of the analysis period, or until more bandwidth is available again.

[0484] In an example, if the RU allocation for one or more data links of the access point changes during an analysis period such that insufficient RUs are available to perform sensing measurement sessions with all devices in the evaluation link set (even with a minimum RU allocation), the access point may interrupt sensing measurements on one or more evaluation links (e.g., on one or more previously idle devices) during the analysis period when insufficient RUs are available. If the analysis period when insufficient RUs are available exceeds a threshold, the access point may remove one or more evaluation links from the evaluation link set for the analysis period.

[0485] In some instances, if an evaluation link that was a sensing link and a data link at the start of the analysis period is no longer a data link during the analysis period, the access point may maintain the RU allocation for the evaluation link for the remaining duration of the analysis period, or may choose to increase or decrease the RU allocation for the evaluation link during the time when the evaluation link is also not being used as a data link. In an example, if the access point establishes an evaluation link with an idle device, and during the analysis period the access point establishes a data link with the device, the access point may adjust the RU allocation allocated to the evaluation link to align with the RU allocation established for the data link.

[0486] In an example, during a TXOP in which data communication is not performed with any device of the evaluation set, the access point may perform a sensing measurement session on the evaluation link, and the access point may allocate a predetermined sensing RU allocation to the evaluation link for the sensing measurement session, wherein the predetermined sensing RU allocation may be different from a data RU allocation for the evaluation link that is also a data link. Similarly, the access point may perform a sensing measurement session only on an evaluation link that is available in the TXOP and not on an evaluation link that is not available, such as an evaluation link used for data transmission in the TXOP.

[0487] In a Wi-Fi sensing system, data transmission and sensing transmission may occur at different TXOPs. An access point may utilize bandwidth in a TXOP that is not used for data transmission for Wi-Fi sensing transmission. In general, an access point may attempt to utilize unused bandwidth in a TXOP for sensing transmission. In one example, an access point may perform sensing measurements on some devices of an evaluation link set in one available TXOP, and may perform sensing measurements on other devices of the evaluation link set in one or more different TXOPs, thereby utilizing available bandwidth in the TXOP and not removing any devices (or removing fewer devices) from the evaluation link set.

[0488] After the RU allocation for the evaluation link, the evaluation links in the evaluation link set can be evaluated within the analysis period. In one embodiment, the access point can monitor the sensing transmission on the multiple evaluation links during the analysis period (or analysis period). In addition, in one embodiment, the access point can be configured to identify the updated sensing link set according to the sensing transmission. In an example, the updated sensing link set may include multiple updated sensing links selected from the multiple evaluation links according to the sensing space coverage metric. In an example, the updating of the sensing link set may involve removing one or more sensing links in the sensing link from the existing sensing link set (or the current sensing link set), and may involve adding one or more evaluation links in the evaluation link that is not a sensing link from the existing sensing link set to the updated sensing link set.

[0489] According to an embodiment, the access point may establish an updated set of sensing links. In an example, after the sensing link set has been updated, the access point may establish multiple sensing sessions for the sensing links in the updated set of sensing links for motion detection purposes. In some embodiments, the sensing sessions may be measured at one or more sampling instances.

[0490] According to an embodiment, the access point may be configured to obtain a plurality of time domain channel representation information (TD-CRI) profile sets corresponding to respective candidate sensing links in the plurality of candidate sensing links. In an example, the plurality of TD-CRI profile sets may include one TD-CRI profile set for each candidate sensing link in the plurality of candidate sensing links obtained in an analysis period, wherein each TD-CRI profile set may include a plurality of TD-CRI profiles, each of the plurality of TD-CRI profiles corresponding to a filter window in the analysis period.

[0491] In one embodiment, the access point may be configured to obtain each TD-CRI profile in the plurality of TD-CRI profile sets for a candidate sensing link in the plurality of candidate sensing links based on obtaining a plurality of TD-CRI measurements at a plurality of sampling instances in a filter window for each candidate sensing link and applying an averaging filter to the plurality of TD-CRI measurements to obtain each TD-CRI profile. In some embodiments, the access point may remove a time shift from one or more of the plurality of TD-CRI measurements before applying the averaging filter.

[0492] In an example, the coverage area of ​​each candidate sensing link can be a function of the reflection structure encountered by the electromagnetic wave between the two devices of the candidate sensing link. The reflection structure can be objectively measured by the CSI packet in the frequency domain. In an example, the CSI packet can be converted to TD-CRI in the time domain. In an example, the TD-CRI of the candidate sensing link at the sampling instance can be represented by the amplitude of the multipath time domain pulse and the time delay of the time domain pulse received at the receiver.

[0493] Fig.31 An example representation 3100 of TD-CRI of candidate sensing links for a sampling instance is depicted in accordance with some embodiments. Fig.31 , the X-axis is a representation of the time delay of the time domain pulse, and the Y-axis is a representation of the amplitude of the time domain pulse. Fig.31 It shows multiple time domain pulses from pulse 1 to pulse P and from τ3 and τ Y In one example, pulse 1 is a line-of-sight time domain pulse, and pulse 1 has the lowest time delay compared to the other time domain pulses. In one embodiment, time domain pulses for further calculations may be selected based on the time domain mask. In an example, time domain pulses with amplitudes greater than a predefined threshold may be selected for further calculations. In some examples, time domain pulses with time delays less than a predefined threshold may be selected for further calculations.

[0494] In one embodiment, generating a TD-CRI profile for a candidate sensing link over a period of time can be used as a representation of the reflection structure of the candidate sensing link. In addition, a TD-CRI with a disturbance in the transmission channel can be defined as a stimulated TD-CRI, and a TD-CRI without a disturbance in the transmission channel can be defined as an unstimulated TD-CRI. In a Wi-Fi system, there may be only a few motion instances in the sensing space during a period of time. If the time period is denoted as T, the time when the stimulated TD-CRI appears is denoted as Te, and the time when the unstimulated TD-CRI appears is denoted as Tu, where Te< <Tu。

[0495] As previously described, the access point may be configured to obtain the multiple TD-CRI measurements at the multiple sampling instances in the filter window for each candidate sensing link and apply an average filter to the multiple TD-CRI measurements to obtain each TD-CRI profile. In one example, by averaging the TD-CRI over a period of time, the TD-CRI will converge to a stable TD-CRI profile. The average filter may be used to average the TD-CRI of the candidate sensing link within the filter window. The TD-CRI profile may be a collection of average values ​​of individual time domain pulses of the TD-CRI for each of the multiple sampling instances in the filter window. Fig.32 An example representation 3200 of a TD-CRI profile for a candidate sensing link is depicted in accordance with some embodiments. Fig.32 in, “amplitude a The variable “a” in ” indicates that the amplitude shown for each time domain pulse is the average amplitude of the time domain pulses over the filter window.

[0496] In addition, as described above, there may be a TD-CRI for a candidate sensing link converted from a CSI packet at the receiver. In an instance, the CSI packet detection delay at the receiver may generate a random amount of receiver time delay, which may result in a difference between the actual phase of the TD-CRI without the receiver time delay and the phase of the TD-CRI with the receiver time delay. The difference can be defined as a phase shift. Before applying the averaging filter, it may be necessary to remove the phase shift from the TD-CRI on the sampling instance because the amplitude of the TD-CRI needs to be averaged and the phase shift may cause inaccuracies in the average amplitude in the averaging filter. Therefore, in one embodiment, the access point may remove the phase shift from the TD-CRI before applying the averaging filter.

[0497] In an example, the averaging filter may include at least one of a low-pass filter (in which the TD-CRI at each sampling instance is given equal weight) and an exponential moving average filter (in which the weights of the TD-CRI are such that the TD-CRI from the most recent sampling instance has a greater weight than the TD-CRI from the earlier sampling instance). Other examples of averaging filters not discussed herein are contemplated herein.

[0498] In addition, in an example, the averaging filter may have a number of taps, the number of taps being the filter window, and the number of taps each representing a TD-CRI sampling instance. In an example, the filter window may be aligned with the size of the FFT / IFFT. For example, if the CSI is generated from a 64-point FFT in the frequency domain, the filter window may be set to 64 taps. In this example, the TD-CRI sampling instance may be referred to as s m 、s m+1 ,…,s m+63 , and the TD-CRI measured for each sampling instance can be referred to as TD-CRI(s m )、TD-CRI(s m+1 ),…,TD-CRI(s m+63 Then, the TD-CRI (s ) of the candidate sensing link can be filtered within the filter window. m )、TD-CRI(s m+1 ),…,TD-CRI(s m+63 ) to find the average.

[0499] According to one embodiment, after obtaining the multiple TD-CRI profile sets corresponding to the corresponding candidate sensing links in the multiple candidate sensing links, the access point can be configured to identify multiple TD-CRI spans corresponding to the corresponding candidate sensing links in the multiple candidate sensing links according to the multiple TD-CRI profile sets. In an example, the output of the average filter for each candidate sensing link can be used to determine the TD-CRI span of the candidate sensing link. In an example, each TD-CRI span in the multiple TD-CRI spans can correspond to a TD-CRI profile set in the multiple TD-CRI profile sets and be selected from a plurality of filter window TD-CRI spans, wherein the multiple filter window TD-CRI spans correspond to the multiple TD-CRI profiles in the TD-CRI profile set. In an example, each filter window TD-CRI span in the multiple filter window TD-CRI spans can be obtained from the corresponding TD-CRI profile. In one embodiment, the access point may select the multiple TD-CRI spans based on determining each TD-CRI span as the maximum filter window TD-CRI span for each TD-CRI profile set. In some embodiments, the access point may select the multiple TD-CRI spans based on determining each TD-CRI span as the average of the multiple filter window TD-CRI spans for each TD-CRI profile set. In one instance, the TD-CRI span of the candidate sensing link may be calculated based on the highest (or last) index of the TD-CRI time domain pulse and the first index of the TD-CRI time domain pulse. In one instance, the filter window TD-CRI span may refer to the TD-CRI span of the candidate sensing link may be calculated based on the highest index of the TD-CRI time domain pulse and the first index of the TD-CRI time domain pulse at the output of the averaging filter.

[0500] In one embodiment, the access point may obtain the plurality of filter window TD-CRI spans based on identifying valid time domain pulses in the corresponding TD-CRI profile as time domain pulses whose amplitude exceeds an amplitude threshold. In an example, the access point may determine the amplitude threshold for each TD-CRI profile as a percentage (e.g., 1% or 2%) of the maximum amplitude of the time domain pulses in the TD-CRI profile. In an example, the access point may tune the amplitude threshold based on an acceptable success rate for motion detection (i.e., the number of successful motion detections divided by the number of motions).

[0501] In one embodiment, the access point may identify the first index of the first valid time domain pulse with the lowest time delay among the valid time domain pulses in the corresponding TD-CRI profile. In addition, the access point may be configured to identify the last index of the last valid time domain pulse with the maximum time delay among the valid time domain pulses in the corresponding TD-CRI profile. The access point may define each filter window TD-CRI span as the last index of the corresponding TD-CRI profile minus the first index. In an example, the last index may be the highest index.

[0502] Assuming that the first index of the first valid TD-CRI time domain pulse (i.e., the time domain pulse with the lowest time delay) is "1" and the last index of the last valid TD-CRI time domain pulse (i.e., the time domain pulse with the largest time delay) is "Q", the TD-CRI span is calculated according to the index of the valid TD-CRI time domain pulse, as shown in Equation 17 below:

[0503] TD-CRI span = Q-1…(17)

[0504] In an example, the TD-CRI span of a candidate sensing link may include multiple valid TD-CRI time domain pulses of the candidate sensing link. The TD-CRI span may also represent the delay spread of the transmission channel and the multipath reflection structure of the candidate sensing link. In an example, the TD-CRI span may be considered as a proxy for the measurement of the coverage area. The wider the TD-CRI span of a candidate sensing link, the more reflections (or coverage area) the candidate sensing link has in the sensing space. In an example, a candidate sensing link with a larger coverage area (and therefore a larger TD-CRI span) may be more sensitive to detecting motion in the sensing space and provide better sensing space coverage.

[0505] According to an embodiment, the access point may be configured to identify a sensing link set based on the plurality of TD-CRI spans. In an example, the sensing link set may include a plurality of selected sensing links selected from the plurality of candidate sensing links. Examples of identifying a sensing link set are described in detail below.

[0506] According to an embodiment, the access point may be configured to monitor sensing transmissions sent over the plurality of candidate sensing links during an analysis period, and the access point may identify a plurality of power changes in the plurality of candidate sensing links based on the sensing transmissions as previously described.

[0507] In one embodiment, the access point may determine a power variation test set as previously described. Based on the power variation test set, the access point may select a first power variation from the plurali...

Claims

1. A method for Wi-Fi sensing performed by a Wi-Fi system, the Wi-Fi system comprising a plurality of networked devices, the plurality of networked devices comprising a plurality of sensing-capable devices and access points, the method comprising: identifying a candidate set of the plurality of networked devices, the candidate set comprising a plurality of candidate devices capable of establishing a transmission link with the access point; establishing a plurality of candidate sensing links between the plurality of candidate devices and the access point; monitoring sensing transmissions sent via the plurality of candidate sensing links; identifying a sensing link set according to the sensing transmission, the sensing link set comprising a plurality of selected sensing links selected from the plurality of candidate sensing links; as well as The plurality of selected sensing links are established between selected devices among the plurality of candidate devices and the access point. 2 . The method of claim 1 , wherein monitoring the sense transmission comprises determining an average power of the sense transmission over an analysis period.

3. The method of claim 1 , wherein monitoring the sensing transmission comprises identifying a plurality of power variations, each power variation being characterized by a grouping of one or more candidate sensing links, the grouping of the one or more candidate sensing links exhibiting a variation in received power compared to an average power of the sensing transmission of the corresponding candidate sensing link for one or more sampling instances during the analysis period. The method of claim 3 , wherein identifying the set of sensing links comprises identifying the plurality of sensing links according to a sensing spatial coverage metric.

5. The method of claim 4, wherein identifying the plurality of sensing links according to the sensing spatial coverage metric comprises: determining, by the sensing spatial coverage metric, a power variation test set comprising a subset of power variations selected from the plurality of power variations for analysis; determining a power ratio parameter for a test power variation in the power variation test set; comparing the power ratio parameter to a ratio threshold factor; and In response to the power ratio parameter exceeding the ratio threshold factor, selected candidate sensing links are selected from the test power variation groups for inclusion in the sensing link set based on the candidate sensing links appearing in a greatest number of the plurality of power variation groups.

6. The method of claim 5, wherein identifying the plurality of sensing links according to the sensing spatial coverage metric further comprises: determining an additional power ratio parameter for an additional power variation in the power variation test set; for each of the additional power changes, comparing the additional power ratio parameter to the ratio threshold factor; and For each additional power variation having an additional power ratio parameter that exceeds the ratio threshold factor, selecting additional selected candidate sensing links from each grouping of the additional power variations for inclusion in the set of sensing links based on the candidate sensing links appearing in a maximum number of the plurality of power variations.

7. The method of claim 5, wherein determining the power variation test set comprises: selecting a first power variation from the plurality of power variations according to a level of importance of the plurality of power variations; and selecting, from the remaining power variations among the plurality of power variations, a second power variation that does not have a candidate sensing link in common with the first power variation, according to importance levels of the remaining power variations among the plurality of power variations; The power change test set includes the first power change and the second power change.

8. The method of claim 7, wherein the power variation test set further comprises one or more additional power variations, such that each candidate sensing link appears in only one group from the first power variation, the second power variation and the one or more additional power variations.

9. The method of claim 7, wherein the importance level is determined based on at least one of: a combined length, the combined length representing the number of candidate sensing links present in the plurality of power variations; a change counter indicating a number of occurrences of each power change from the plurality of power changes; and A maximum string length represents a maximum number of consecutive occurrences of each power variation from the plurality of power variations.

10. The method of claim 5, wherein determining the power ratio parameter comprises dividing a first maximum string length representing a maximum number of consecutive occurrences of a test power change from the power change test set in the analysis period by a second maximum string length representing a maximum number of consecutive occurrences of a single-link power change from each candidate sensing link associated with the group of the test power changes in the analysis period.

11. The method of claim 5, wherein determining the power ratio parameter comprises dividing a first change counter representing a number of occurrences of a test power change from the power change test set in the analysis period by a second change counter representing a maximum number of occurrences of a single link power change from each candidate sensing link associated with the group of the test power changes in the analysis period.

12. A system for Wi-Fi sensing, the system comprising a plurality of networked devices, the plurality of networked devices including a plurality of sensing-capable devices and access points, the system being configured to: identifying a candidate set of the plurality of networked devices, the candidate set comprising a plurality of candidate devices capable of establishing a transmission link with the access point; establishing a plurality of candidate sensing links between the plurality of candidate devices and the access point; monitoring sensing transmissions sent via the plurality of candidate sensing links; identifying a sensing link set according to the sensing transmission, the sensing link set comprising a plurality of selected sensing links selected from the plurality of candidate sensing links; as well as The plurality of selected sensing links are established between selected devices among the plurality of candidate devices and the access point.

13. The system of claim 12, wherein monitoring the sensed transmission comprises determining an average power of the sensed transmission over an analysis period.

14. The system of claim 12, wherein monitoring the sensing transmission comprises identifying a plurality of power variations, each power variation being characterized by a grouping of one or more candidate sensing links, the grouping of the one or more candidate sensing links exhibiting a variation in received power compared to an average power of the sensing transmission of the corresponding candidate sensing link for one or more sampling instances during the analysis period.

15. The system of claim 14, wherein identifying the set of sensing links comprises identifying the plurality of sensing links according to a sensing spatial coverage metric.

16. The system of claim 15, wherein identifying the plurality of sensing links according to the sensing spatial coverage metric comprises: determining, by the sensing spatial coverage metric, a power variation test set comprising a subset of power variations selected from the plurality of power variations for analysis; determining a power ratio parameter for a test power variation in the power variation test set; comparing the power ratio parameter to a ratio threshold factor; and In response to the power ratio parameter exceeding the ratio threshold factor, selected candidate sensing links are selected from the test power variation groups for inclusion in the sensing link set based on the candidate sensing links appearing in a greatest number of the plurality of power variation groups.

17. The system of claim 16, wherein identifying the plurality of sensing links according to the sensing spatial coverage metric further comprises: determining an additional power ratio parameter for an additional power variation in the power variation test set; for each of the additional power changes, comparing the additional power ratio parameter to the ratio threshold factor; and For each additional power variation having an additional power ratio parameter that exceeds the ratio threshold factor, selecting additional selected candidate sensing links from each grouping of the additional power variations for inclusion in the set of sensing links based on the candidate sensing links appearing in a maximum number of the plurality of power variations.

18. The system of claim 16, wherein determining the power variation test set comprises: selecting a first power variation from the plurality of power variations according to a level of importance of the plurality of power variations; and selecting, from the remaining power variations among the plurality of power variations, a second power variation that does not have a candidate sensing link in common with the first power variation, according to importance levels of the remaining power variations among the plurality of power variations; The power change test set includes the first power change and the second power change.

19. The system of claim 18, wherein the power variation test set further comprises one or more additional power variations, such that each candidate sensing link appears in only one group from the first power variation, the second power variation, and the one or more additional power variations.

20. The system of claim 18, wherein the importance level is determined based on at least one of: a combined length, the combined length representing the number of candidate sensing links present in the plurality of power variations; a change counter indicating a number of occurrences of each power change from the plurality of power changes; and A maximum string length represents a maximum number of consecutive occurrences of each power variation from the plurality of power variations.

21. A system according to claim 16, wherein determining the power ratio parameter includes dividing a first maximum string length by a second maximum string length, wherein the first maximum string length represents a maximum consecutive number of occurrences of a test power change from the power change test set in the analysis period, and the second maximum string length represents a maximum consecutive number of occurrences of a single link power change associated with each candidate sensing link of the grouping of the test power changes in the analysis period.

22. The system of claim 16, wherein determining the power ratio parameter comprises dividing a first change counter representing a number of occurrences of a test power change from the power change test set in the analysis period by a second change counter representing a maximum number of occurrences of a single link power change from each candidate sensing link associated with the group of the test power changes in the analysis period.

23. A method for Wi-Fi sensing performed by a Wi-Fi system, the Wi-Fi system comprising a plurality of networked devices, the plurality of networked devices comprising a plurality of sensing-capable devices and access points, the method comprising: maintaining a plurality of selected sensing links as a set of sensing links between selected ones of the plurality of sensing-capable devices and the access point; identifying a plurality of candidate links as a set of candidate links between unselected devices of the plurality of sensing-capable devices and the access point; identifying a plurality of evaluation links from the candidate link set and the sensing link set as an evaluation link set; determining an allocation of channel resources for the plurality of evaluation links; establishing the plurality of evaluation links according to the allocation; monitoring sense transmissions on the plurality of evaluation links during an analysis period; identifying an updated set of sensing links according to the sensing transmission, the updated set of sensing links comprising a plurality of updated sensing links selected from the plurality of evaluation links according to a sensing space coverage metric; The updated set of sensing links is established.

24. The method of claim 23, wherein identifying the plurality of candidate links comprises: performing a discovery process on devices having sensing capabilities; and The discovered sensing-capable devices are included as candidate devices in a candidate link set representing candidate links.

25. The method of claim 23, wherein identifying the plurality of candidate links comprises: identifying a fine tuning link not included in the set of sensing links; and The fine-tuning link is included as a candidate link in the candidate link set.

26. The method of claim 23, wherein determining the set of evaluation links comprises: selecting one or more sensing links of the plurality of sensing links as evaluation links; and A subset of the plurality of candidate links is selected as evaluation links.

27. The method of claim 26, further comprising: Determining that a congestion metric of the access point is above a congestion threshold; as well as One or more active sensing-capable devices among the candidate devices in the candidate link set are selected for inclusion in the evaluation link set.

28. A method according to claim 27, wherein determining the allocation of the channel resources for the one or more active sensing-capable devices included in the evaluation link set includes maintaining an existing allocation of resource units (RUs) for the one or more active sensing-capable devices included in the evaluation link set.

29. The method of claim 26, further comprising: Determining that a congestion metric of the access point is below a congestion threshold; as well as One or more idle sensing-capable devices among the candidate devices in the candidate link set are selected for inclusion in the evaluation link set.

30. The method of claim 29, wherein determining the allocation of the channel resources for the one or more idle sensing-capable devices included in the evaluation link set comprises allocating resource units (RUs) to the one or more idle sensing-capable devices included in the evaluation link set.

31. The method of claim 29, further comprising: Selecting one or more active sensing-capable devices among the candidate devices in the candidate link set to include in the evaluation link set, wherein determining an allocation of the channel resources for the sensing-capable devices included in the evaluation link set comprises: Maintain the existing allocation of RUs for the selected devices, allocating RUs for the one or more idle sensing-capable devices, and The existing allocation of RUs is maintained for the one or more active sensing-capable devices.

32. The method of claim 23, further comprising: A reallocation of channel resources is determined for the plurality of evaluation links based on changes in data link bandwidth on the plurality of evaluation links during an analysis period.

33. A system for Wi-Fi sensing, the system comprising a plurality of networked devices, the plurality of networked devices comprising a plurality of sensing-capable devices and access points, the system being configured to: maintaining a plurality of selected sensing links as a set of sensing links between selected ones of the plurality of sensing-capable devices and the access point; identifying a plurality of candidate links as a set of candidate links between unselected devices of the plurality of sensing-capable devices and the access point; identifying a plurality of evaluation links from the candidate link set and the sensing link set as an evaluation link set; determining an allocation of channel resources for the plurality of evaluation links; establishing the plurality of evaluation links according to the allocation; monitoring sense transmissions on the plurality of evaluation links during an analysis period; identifying an updated set of sensing links according to the sensing transmission, the updated set of sensing links comprising a plurality of updated sensing links selected from the plurality of evaluation links according to a sensing space coverage metric; The updated set of sensing links is established.

34. The system of claim 33, wherein identifying the plurality of candidate links comprises: performing a discovery process on devices having sensing capabilities; and The discovered sensing-capable devices are included as candidate devices in a candidate link set representing candidate links.

35. The system of claim 33, wherein identifying the plurality of candidate links comprises: identifying a fine tuning link not included in the set of sensing links; and The fine-tuning link is included as a candidate link in the candidate link set.

36. The system of claim 33, wherein determining the set of evaluation links comprises: selecting one or more sensing links of the plurality of sensing links as evaluation links; and A subset of the plurality of candidate links is selected as evaluation links.

37. The system of claim 36, further comprising: Determining that a congestion metric of the access point is above a congestion threshold; as well as One or more active sensing-capable devices among the candidate devices in the candidate link set are selected for inclusion in the evaluation link set.

38. A system according to claim 37, wherein determining the allocation of the channel resources for the one or more active sensing-capable devices included in the evaluation link set includes maintaining an existing allocation of resource units (RUs) for the one or more active sensing-capable devices included in the evaluation link set.

39. The system of claim 36, wherein the system is further configured to: determining that a congestion metric of the access point is below a congestion threshold; and One or more idle sensing-capable devices among the candidate devices in the candidate link set are selected for inclusion in the evaluation link set.

40. A system according to claim 39, wherein determining the allocation of the channel resources for the one or more idle sensing-capable devices included in the evaluation link set includes allocating resource units (RUs) to the one or more idle sensing-capable devices included in the evaluation link set.

41. The system of claim 39, wherein the system is further configured to: Selecting one or more active sensing-capable devices among the candidate devices in the candidate link set to include in the evaluation link set, wherein determining an allocation of the channel resources for the sensing-capable devices included in the evaluation link set comprises: Maintain the existing allocation of RUs for the selected devices, allocating RUs for the one or more idle sensing-capable devices, and The existing allocation of RUs is maintained for the one or more active sensing-capable devices.

42. The system of claim 33, wherein the system is further configured to: A reallocation of channel resources is determined for the plurality of evaluation links based on changes in data link bandwidth on the plurality of evaluation links during an analysis period.

43. A method for Wi-Fi sensing performed by a Wi-Fi system, the Wi-Fi system comprising a plurality of networked devices, the plurality of networked devices comprising a plurality of sensing-capable devices and access points, the method comprising: obtaining sensing probe information, the sensing probe information comprising information regarding a plurality of power variations in a plurality of candidate sensing links between the plurality of sensing-capable devices and the access point, each power variation being characterized by a grouping of one or more candidate sensing links, the grouping of the one or more candidate sensing links exhibiting a variation in received power compared to an average power of sensed transmissions of the corresponding candidate sensing link during one or more sampling instances of an analysis period; determining a plurality of data usage values ​​corresponding to the plurality of candidate sensing links; identifying a sensing link set according to a sensing spatial coverage metric determined from the sensing probe information and the plurality of data usage values, the sensing link set comprising a plurality of representative sensing links selected from the plurality of candidate sensing links; as well as The plurality of representative sensing links are established between corresponding sensing-capable devices among the plurality of sensing-capable devices and the access point.

44. The method of claim 43, wherein: Obtaining the sensing detection information includes: establishing a plurality of candidate sensing links between the plurality of sensing-capable devices and the access point, monitoring sensing transmissions sent over the plurality of candidate sensing links during the analysis period, and The plurality of power variations are identified based on the sensed transmission.

45. The method of claim 43, wherein: Obtaining the sensing detection information includes accessing previously stored sensing information, and The plurality of candidate sensing links include original sensing links in a previously established sensing link set and fine-tuning sensing links not included in the previously established sensing link set, and each power variation has at least one original sensing link.

46. ​​The method of claim 45, wherein identifying the set of sensing links comprises: identifying a congestion sensing link from among the original sensing links as having a corresponding data usage value from among the plurality of data usage values ​​that exceeds a congestion threshold; identifying a power change corresponding to the congestion sensing link; identifying one or more fine-tuning sensing links belonging to the power variation; as well as The representative sensing link for the power variation is selected from the congestion sensing link and the one or more fine-tuning sensing links.

47. The method of claim 46, wherein identifying the set of sensing links further comprises: identifying additional congestion sensing links from the original sensing links based on the plurality of data usage values; identifying an additional power change corresponding to the additional congestion sensing link; identifying an additional set of one or more fine-tuning sensing links belonging to the additional power variation; as well as For each additional power change, a corresponding representative sensing link is selected from the corresponding additional congestion sensing link and the corresponding additional set of one or more fine-tuning sensing links.

48. The method of claim 46, wherein selecting the representative sensing link further comprises: The fine-tuning sensing link that appears in a plurality of groups representing a maximum number of the plurality of power variations is selected as the representative sensing link.

49. The method of claim 46, wherein selecting the representative sensing link further comprises: The fine-tuning sensing link having the lowest data usage value among the plurality of data usage values ​​is selected as the representative sensing link.

50. The method of claim 46, wherein the representative sensing link for the power variation is selected from the congestion sensing link and the one or more fine-tuning sensing links according to a switching factor defined for each of the congestion sensing link and the one or more fine-tuning sensing links.

51. The method of claim 50, wherein the switching factor is defined as the number of occurrences of a link in the grouping of the plurality of power variations divided by a data usage value corresponding to the link.

52. The method of claim 50, wherein the power variation includes the congestion sensing link and the non-congestion fine-tuning sensing link, and the representative sensing link is selected from the congestion sensing link and the non-congestion fine-tuning sensing link according to a highest switching factor.

53. The method of claim 50, wherein the power variation includes the congestion sensing link and a plurality of non-congestion fine-tuning sensing links, and the representative sensing link is selected from the congestion sensing link and the plurality of non-congestion fine-tuning sensing links according to a highest switching factor.

54. The method of claim 53, wherein the representative sensing link is further selected from two non-congested fine-tuning sensing links having the same switching factor according to the non-congested fine-tuning sensing link having a lower link number.

55. The method of claim 46, wherein the representative sensing link for the power variation is selected to balance link loads in the set of sensing links.

56. A system for Wi-Fi sensing, the system comprising a plurality of networked devices, the plurality of networked devices comprising a plurality of sensing-capable devices and access points, the system being configured to: obtaining sensing probe information, the sensing probe information comprising information regarding a plurality of power variations in a plurality of candidate sensing links between the plurality of sensing-capable devices and the access point, each power variation being characterized by a grouping of one or more candidate sensing links, the grouping of the one or more candidate sensing links exhibiting a variation in received power compared to an average power of sensed transmissions of the corresponding candidate sensing link during one or more sampling instances of an analysis period; determining a plurality of data usage values ​​corresponding to the plurality of candidate sensing links; identifying a sensing link set according to a sensing spatial coverage metric determined from the sensing probe information and the plurality of data usage values, the sensing link set comprising a plurality of representative sensing links selected from the plurality of candidate sensing links; as well as The plurality of representative sensing links are established between corresponding sensing-capable devices among the plurality of sensing-capable devices and the access point.

57. The system of claim 56, wherein: Obtaining the sensing detection information includes: establishing a plurality of candidate sensing links between the plurality of sensing-capable devices and the access point, monitoring sensing transmissions sent over the plurality of candidate sensing links during the analysis period, and The plurality of power variations are identified based on the sensed transmission.

58. The system of claim 56, wherein: Obtaining the sensing detection information includes accessing previously stored sensing information, and The plurality of candidate sensing links include original sensing links in a previously established sensing link set and fine-tuning sensing links not included in the previously established sensing link set, and each power variation has at least one original sensing link.

59. The system of claim 58, wherein identifying the set of sensing links comprises: identifying a congestion sensing link from among the original sensing links as having a corresponding data usage value from among the plurality of data usage values ​​that exceeds a congestion threshold; identifying a power change corresponding to the congestion sensing link; identifying one or more fine-tuning sensing links belonging to the power variation; as well as The representative sensing link for the power variation is selected from the congestion sensing link and the one or more fine-tuning sensing links.

60. The system of claim 59, wherein identifying the set of sensing links further comprises: identifying additional congestion sensing links from the original sensing links based on the plurality of data usage values; identifying an additional power change corresponding to the additional congestion sensing link; identifying an additional set of one or more fine-tuning sensing links belonging to the additional power variation; as well as For each additional power change, a corresponding representative sensing link is selected from the corresponding additional congestion sensing link and the corresponding additional set of one or more fine-tuning sensing links.

61. The system of claim 59, wherein selecting the representative sensing link further comprises: The fine-tuning sensing link that appears in a plurality of groups representing a maximum number of the plurality of power variations is selected as the representative sensing link.

62. The system of claim 59, wherein selecting the representative sensing link further comprises: The fine-tuning sensing link having the lowest data usage value among the plurality of data usage values ​​is selected as the representative sensing link.

63. The system of claim 59, wherein the representative sensing link for the power variation is selected from the congestion sensing link and the one or more fine-tuning sensing links based on a switching factor defined for each of the congestion sensing link and the one or more fine-tuning sensing links.

64. The system of claim 63, wherein the switching factor is defined as the number of occurrences of a link in the grouping of the plurality of power variations divided by a data usage value corresponding to the link.

65. The system of claim 63, wherein the power variation includes the congestion sensing link and the non-congestion fine-tuning sensing link, and the representative sensing link is selected among the congestion sensing link and the non-congestion fine-tuning sensing link according to a highest switching factor.

66. The system of claim 63, wherein the power variation includes the congestion sensing link and a plurality of non-congestion fine-tuning sensing links, and the representative sensing link is selected from the congestion sensing link and the plurality of non-congestion fine-tuning sensing links according to a highest switching factor.

67. The system of claim 66, wherein the representative sensing link is further selected from two non-congested fine-tuning sensing links having the same switching factor according to the non-congested fine-tuning sensing link having a lower link number.

68. The system of claim 63, wherein the representative sensing link for the power variation is selected to balance link loads in the set of sensing links.

69. A method for Wi-Fi sensing performed by a Wi-Fi system, the Wi-Fi system comprising a plurality of networked devices, the plurality of networked devices comprising a plurality of sensing-capable devices and access points, the method comprising: identifying a candidate set of the plurality of networked devices, the candidate set comprising a plurality of candidate devices capable of establishing a transmission link with the access point; establishing a plurality of candidate sensing links between the plurality of candidate devices and the access point; obtaining a plurality of time domain channel representation information (TD-CRI) profile sets corresponding to respective candidate sensing links among the plurality of candidate sensing links; identifying, according to the plurality of TD-CRI profile sets, a plurality of TD-CRI spans corresponding to respective candidate sensing links among the plurality of candidate sensing links; identifying a sensing link set according to the plurality of TD-CRI spans, the sensing link set comprising a plurality of selected sensing links selected from the plurality of candidate sensing links; as well as The plurality of selected sensing links are established between selected ones of the candidate devices and the access point.

70. The method of claim 69, wherein obtaining each TD-CRI profile in the plurality of TD-CRI profile sets for a candidate sensing link in the plurality of candidate sensing links comprises: For each candidate sensing link, at multiple sampling instances in the filter window obtaining multiple TD-CRI measurement results; and An averaging filter is applied to the plurality of TD-CRI measurements to obtain each TD-CRI profile.

71. The method of claim 70, wherein the averaging filter comprises at least one of: Low pass filter and exponential moving average filter.

72. The method of claim 70, further comprising removing time shift from one or more TD-CRI measurements of the plurality of TD-CRI measurements before applying the averaging filter.

73. A method according to claim 69, wherein the multiple TD-CRI profile sets include a TD-CRI profile set for each of the multiple candidate sensing links obtained within an analysis period, wherein each TD-CRI profile set includes multiple TD-CRI profiles, and the multiple TD-CRI profiles each correspond to a filter window in the analysis period.

74. A method according to claim 73, wherein each TD-CRI span of the multiple TD-CRI spans corresponds to a TD-CRI profile set in the multiple TD-CRI profile sets and is selected from a plurality of filter window TD-CRI spans, wherein the plurality of filter window TD-CRI spans correspond to the plurality of TD-CRI profiles in the TD-CRI profile set.

75. The method of claim 74, wherein selecting the plurality of TD-CRI spans comprises: Each TD-CRI span is determined as the maximum filter window TD-CRI span for each TD-CRI profile set.

76. The method of claim 74, wherein selecting the plurality of TD-CRI spans comprises: Each TD-CRI span is determined for each TD-CRI profile set as an average of the plurality of filter window TD-CRI spans.

77. The method of claim 74, wherein each filter window TD-CRI span of the plurality of filter window TD-CRI spans is obtained from a corresponding TD-CRI profile, and obtaining the plurality of filter window TD-CRI spans comprises: Identify a valid time domain pulse in the corresponding TD-CRI profile as a time domain pulse whose amplitude exceeds an amplitude threshold; Identify a first index of a first valid time domain pulse having a lowest time delay among the valid time domain pulses in the corresponding TD-CRI profile; Identifying a last index of a last valid time domain pulse having a maximum time delay among the valid time domain pulses in the corresponding TD-CRI profile; and Each filter window TD-CRI span is defined as the last index of the corresponding TD-CRI profile minus the first index.

78. The method of claim 77, wherein for each TD-CRI profile, the amplitude threshold is determined as a percentage relative to a maximum amplitude of time domain pulses in the TD-CRI profile.

79. The method of claim 69, wherein identifying a set of sensing links according to the plurality of TD-CRI spans comprises: identifying a plurality of power variations, each power variation being characterized by a grouping of one or more candidate sensing links, the grouping of the one or more candidate sensing links exhibiting a variation in received power compared to an average power of sensed transmissions of the corresponding candidate sensing link for one or more sampling instances during an analysis period; determining a power variation test set comprising a subset of power variations selected from the plurality of power variations; and For each power variation in the power variation test set, a selected candidate sensing link is selected from the grouping of the test power variations for inclusion in the sensing link set according to the candidate sensing link having a largest TD-CRI span.

80. A system for Wi-Fi sensing, the system comprising a plurality of networked devices, the plurality of networked devices comprising a plurality of sensing-capable devices and access points, the system being configured to: identifying a candidate set of the plurality of networked devices, the candidate set comprising a plurality of candidate devices capable of establishing a transmission link with the access point; establishing a plurality of candidate sensing links between the plurality of candidate devices and the access point; obtaining a plurality of time domain channel representation information (TD-CRI) profile sets corresponding to respective candidate sensing links among the plurality of candidate sensing links; identifying, according to the plurality of TD-CRI profile sets, a plurality of TD-CRI spans corresponding to respective candidate sensing links among the plurality of candidate sensing links; identifying a sensing link set according to the plurality of TD-CRI spans, the sensing link set comprising a plurality of selected sensing links selected from the plurality of candidate sensing links; and The plurality of selected sensing links are established between selected ones of the candidate devices and the access point.

81. The system of claim 80, wherein obtaining each TD-CRI profile in the plurality of TD-CRI profile sets for a candidate sensing link in the plurality of candidate sensing links comprises: For each candidate sensing link, at multiple sampling instances in the filter window obtaining multiple TD-CRI measurement results; and An averaging filter is applied to the plurality of TD-CRI measurements to obtain each TD-CRI profile.

82. The system of claim 81, wherein the averaging filter comprises at least one of: Low pass filter and exponential moving average filter.

83. The system of claim 81, wherein the system is further configured to remove time shift from one or more TD-CRI measurements of the plurality of TD-CRI measurements before applying the averaging filter.

84. A system according to claim 80, wherein the multiple TD-CRI profile sets include a TD-CRI profile set for each of the multiple candidate sensing links obtained within an analysis period, wherein each TD-CRI profile set includes multiple TD-CRI profiles, and the multiple TD-CRI profiles each correspond to a filter window in the analysis period.

85. A system according to claim 84, wherein each TD-CRI span of the multiple TD-CRI spans corresponds to a TD-CRI profile set in the multiple TD-CRI profile sets and is selected from a plurality of filter window TD-CRI spans, wherein the plurality of filter window TD-CRI spans correspond to the plurality of TD-CRI profiles in the TD-CRI profile set.

86. The system of claim 85, wherein selecting the plurality of TD-CRI spans comprises: Each TD-CRI span is determined as the maximum filter window TD-CRI span for each TD-CRI profile set.

87. The system of claim 85, wherein selecting the plurality of TD-CRI spans comprises: Each TD-CRI span is determined for each TD-CRI profile set as an average of the plurality of filter window TD-CRI spans.

88. The system of claim 85, wherein each filter window TD-CRI span of the plurality of filter window TD-CRI spans is obtained from a corresponding TD-CRI profile, and obtaining the plurality of filter window TD-CRI spans comprises: Identify a valid time domain pulse in the corresponding TD-CRI profile as a time domain pulse whose amplitude exceeds an amplitude threshold; Identify a first index of a first valid time domain pulse having a lowest time delay among the valid time domain pulses in the corresponding TD-CRI profile; Identifying a last index of a last valid time domain pulse having a maximum time delay among the valid time domain pulses in the corresponding TD-CRI profile; and Each filter window TD-CRI span is defined as the last index of the corresponding TD-CRI profile minus the first index.

89. The system of claim 88, wherein for each TD-CRI profile, the amplitude threshold is determined as a percentage relative to a maximum amplitude of time domain pulses in the TD-CRI profile.

90. The system of claim 80, wherein identifying a set of sensing links according to the plurality of TD-CRI spans comprises: identifying a plurality of power variations, each power variation being characterized by a grouping of one or more candidate sensing links, the grouping of the one or more candidate sensing links exhibiting a variation in received power compared to an average power of sensed transmissions of the corresponding candidate sensing link for one or more sampling instances during an analysis period; determining a power variation test set comprising a subset of power variations selected from the plurality of power variations; and For each power variation in the power variation test set, a selected candidate sensing link is selected from the grouping of the test power variations for inclusion in the sensing link set according to the candidate sensing link having a largest TD-CRI span.

Images