System and method for disambiguation of multi-link device identities for WLAN sensing operation

Abstract

Systems and methods are disclosed for disambiguation of multi-link device (MLD) identities for WLAN sensing operation. The method includes receiving a first Association Request frame from a first non-AP MLD and assigning a first Link Group ID to the first non- Access Point (AP) MLD, transmitting a first Association Response frame to the first non-AP MLD and receiving a second Association Request frame from a second non-AP MLD. Thereafter, the method includes assigning a second Link Group ID to the second non-AP MLD and transmitting a second Association Response frame to the second non-AP MLD and transmitting a first Sensing Measurement Request frame to a first station affiliated with the first non-AP MLD to establish a first sensing measurement session and transmitting a second Sensing Measurement Request frame to a second station affiliated with the second non-AP MLD to establish a second sensing measurement session.

Description

SYSTEM AND METHOD FOR DISAMBIGUATION OF MULTI-LINK DEVICE IDENTITIES FOR WLAN SENSING OPERATION TECHNICAL FIELD

[0001] The present disclosure generally relates to systems and methods for wireless local area (WLAN) sensing. In particular, the present disclosure relates to systems and methods for disambiguation of multi-link device identities for WLAN sensing operation.BACKGROUND OF THE DISCLOSURE

[0002] Motion detection systems have been used to detect movement, for example, of objects in a room or an outdoor area. In some example motion detection systems, infrared or optical sensors are used to detect movement of objects in the sensor’s field of view. Motion detection systems have been used in security systems, automated control systems, and other types of systems. A WLAN sensing system (which may be referred to as a Wi-Fi sensing system) is one recent addition to motion detection systems. The WLAN sensing system may be a network of Wi-Fi-enabled devices that may be a part of an Institute for Electrical and Electronics Engineers (IEEE) 802.11 network. For example, the WLAN sensing system may be configured to detect features of interest in a sensing space. The sensing space may refer to any physical space in which the WLAN sensing system may operate, such as a place of residence, a place of work, a shopping mall, a sports hall or sports stadium, a garden, or any other physical space. Features of interest may include motion of objects and motion tracking, presence detection, intrusion detection, gesture recognition, fall detection, breathing rate detection, and other applications.

[0003] Furthermore, the motion is determined in the sensing space by a sensing application / technique on a device detecting perturbation in the local environment based on analysis of sensing measurements (channel state information) over time. Furthermore, a sensing transmission is sent from a sensing transmitter. Furthermore, a sensing receiver performs a sensing measurement at the Physical (PHY) layer and Media Access Control (MAC) layer and passes this sensing measurement up to the sensing agent or sensing application at a higher layer to detect motion.

[0004] Furthermore, a basic service set (BSS) is a set of an Access Point Station (AP STA, or simply AP), and non-AP STAs associated together at the PHY / MAC layers to form a wireless network. The BSS comprises a single device acting as an access point (AP or AP STA) and one or more devices connected to and controlled by the AP (non-AP STA, or simply STAwhere the access point is AP). A BSS is identified in IEEE 802.11 by a basic service set identifier (BSSID). Furthermore, an extended services set (ESS) is a set of STAs that includes a set of APs and forms a single logical service set. The ESS is a group of two or more BSSs and is logically identified by a service set identifier (SSID) representing the overall wireless network. The ESS allows client devices to roam between different BSSs while maintaining connectivity to the network.BRIEF SUMMARY OF THE DISCLOSURE

[0005] The present disclosure generally relates to systems and methods for establishing a WLAN sensing network. In particular, the present disclosure relates to systems and methods for disambiguation of multi-link device identities for WLAN sensing operation.

[0006] Methods are provided to perform sensing measurements. In an example, a method for disambiguation of multi-link device identities for WLAN sensing operation is described. The method is carried out by an access point multi-link device (AP MLD) including a transmitting antenna, a receiving antenna, a plurality of radios, and at least one processor configured to execute instructions. The method includes receiving a first Association Request frame from a first non-AP multi-link device (MLD). Furthermore, the method includes assigning a first Link Group ID to the first non-AP MLD. The method further includes transmitting a first Association Response frame to the first non-AP MLD, the first Association Response frame including the first Link Group ID. Furthermore, the method includes receiving a second Association Request frame from a second non-AP MLD. Thereafter, the method includes assigning a second Link Group ID to the second non-AP MLD. Furthermore, the method includes transmitting a second Association Response frame to the second non-AP MLD, the second Association Response frame including the second Link Group ID. The method also includes transmitting a first Sensing Measurement Request frame to a first station affiliated with the first non-AP MLD to establish a first sensing measurement session. The method further includes transmitting a second Sensing Measurement Request frame to a second station affiliated with the second non-AP MLD to establish a second sensing measurement session.

[0007] In some embodiments, the first Association Request frame includes first sensing capabilities of one or more non-AP stations affiliated with the first non-AP MLD.

[0008] In some embodiments, the first Link Group ID identifies multi-links between the AP MLD and the first non-AP MLD.

[0009] In some embodiments, the first Link Group ID identifies multi-links that support sensing between the AP MLD and the first non-AP MLD.

[0010] In some embodiments, the method includes generating the first Sensing Measurement Request frame based on the first Link Group ID and generating the second Sensing Measurement Request frame based on the second Link Group ID.

[0011] In some embodiments, the first Association Response frame includes first AP sensing capabilities of one or more APs affiliated with the AP MLD.

[0012] In some embodiments, the first Association Request frame includes first sensing capabilities of one or more non-AP stations affiliated with the first non-AP MLD and the second Association Request frame includes second sensing capabilities of one or more non-AP stations affiliated with the second non-AP MLD. Furthermore, the method includes generating the first Sensing Measurement Request frame based on the first Link Group ID and the first sensing capabilities and generating the second Sensing Measurement Request frame based on the second Link Group ID and the second sensing capabilities.

[0013] In some embodiments, generating the first Sensing Measurement Request frame is further based on a sensing goal.

[0014] In some embodiments, the method includes transmitting a plurality of Beacon frames by the plurality of radios including information about the access point multi-link device (AP MLD). Furthermore, the method includes receiving a Probe Request frame from the first non-AP MLD. The method further includes transmitting a Probe Response frame including sensing capabilities of the AP MLD.BRIEF DESCRIPTION OF THE DRAWINGS

[0015] FIG. 1 is a diagram showing an example wireless communication system.

[0016] FIG. 2A and FIG. 2B are diagrams showing example wireless signals communicated between wireless communication devices.

[0017] FIG. 3 A and FIG. 3B are plots showing examples of channel responses computed from the wireless signals communicated between wireless communication devices in FIG. 2A and FIG. 2B.

[0018] FIG. 4A and FIG. 4B are diagrams showing example channel responses associated with the motion of an object in distinct regions of a space.

[0019] FIG. 4C and FIG. 4D are plots showing the example channel responses of FIG. 4A and FIG. 4B overlaid on an example channel response associated with no motion occurring in the space.

[0020] FIG. 5 depicts an implementation of some of the architecture of a system to perform disambiguation of multi-link device identities for Wireless Local Area Network (WLAN) sensing operation, according to some embodiments.

[0021] FIG. 6 depicts an example of a WLAN sensing procedure, according to some embodiments.

[0022] FIG. 7A depicts an example of a Sensing Measurement Setup Request frame Action field format, according to some embodiments.

[0023] FIG. 7B illustrates an example of a Sensing Measurement Parameters element, according to some embodiments.

[0024] FIG. 7C illustrates an example of a format of a Sensing Measurement Parameters field, according to some embodiments.

[0025] FIG. 7D depicts an example of a Sensing Measurement Setup Response frame Action field format, according to some embodiments.

[0026] FIG. 8A depicts one-to-many and many-to-one aspects of an example of a WLAN sensing procedure, according to some embodiments.

[0027] FIG. 8B depicts pairwise aspects of an example of a WLAN sensing procedure, according to some embodiments.

[0028] FIG. 9A and FIG. 9B depict an example of message flows of a trigger-based (TB) sensing measurement exchange of a WLAN sensing procedure that consists of a sensing measurement setup phase, a Null Data PHY-layer Protocol Data Unit (PPDU) Announcement (NDPA) sounding and reporting phase, a trigger-frame (TF) sounding phase, and a sensing measurement setup termination phase, according to some embodiments.

[0029] FIG. 10A depicts an example of phases of a TB sensing measurement exchange, according to some embodiments.

[0030] FIG. 10B indicates valid combinations of phases of a TB sensing measurement exchange, according to some embodiments.

[0031] FIG. 11 depicts an example of a TB sensing measurement exchange including a polling phase, an NDPA sounding phase, a TF sounding phase, and a reporting phase, according to some embodiments.

[0032] FIG. 12A and FIG. 12B depict a message flow of a non-TB sensing measurement exchange of a WLAN sensing procedure that consists of a sensing measurement setup phase, an NDPA sounding phase with sensing initiator to sensing responder (SI2SR) sounding and reporting, an NDPA sounding phase with sensing responder to sensing initiator (SR2SI) sounding, an NDPA sounding phase with both SI2SR sounding and reporting and SR2SIsounding, and a sensing measurement setup termination phase, according to some embodiments.

[0033] FIG. 13 depicts an example of a single non-TB sensing measurement exchange consisting of a measurement sounding phase and a reporting phase, according to some embodiments.

[0034] FIG. 14A and FIG. 14B depict an example of an Action field format of a Sensing Measurement Report frame Action field and a Sensing Measurement Report Container field format, according to some embodiments.

[0035] FIG. 15A to FIG. 151 depict a hierarchy of fields within a Sensing Trigger frame, according to some embodiments.

[0036] FIG. 16 depicts an exemplary Multi -Link Operation (MLO) of two Multi -Link Devices (MLDs), according to some embodiments.

[0037] FIG. 17 depicts an exemplary process of sharing sensing capabilities of links of an AP MLD, according to some embodiments.

[0038] FIG. 18 depicts an exemplary enhanced Beacon frame that supports communication of support for WLAN sensing by the AP MLD, according to some embodiments.

[0039] FIG. 19 depicts an exemplary enhanced MLD parameters subfield format to support WLAN sensing, according to some embodiments.

[0040] FIG. 20 depicts an exemplary enhanced multi-link Probe Request frame transmitted during MLO discovery, according to some embodiments.

[0041] FIG. 21 depicts an exemplary enhanced multi-link Probe Response frame describing the sensing capabilities of the AP MLD, according to some embodiments.

[0042] FIG. 22 depicts an exemplary enhanced Common Info field of a Basic Multi-Link element which supports communication of sensing capabilities of an MLD, according to some embodiments.

[0043] FIG. 23 depicts an exemplary enhanced Presence Bitmap subfield of the Basic Multi-Link element which supports the communication of the sensing capabilities of the MLD, according to some embodiments.

[0044] FIG. 24 depicts an exemplary enhanced station (STA) Info field format of per-STA profile sub-element of the Basic Multi-Link element which supports the communication of sensing capabilities of the STA affiliated with the MLD, according to some embodiments.

[0045] FIG. 25 depicts an exemplary enhanced STA Control field format of the Basic Multi-Link element which supports the communication of the sensing capabilities of the STA affiliated with the MLD.

[0046] FIG. 26 depicts an exemplary STA Sensing Capabilities subfield format, according to some embodiments.

[0047] FIG. 27 depicts an exemplary process to (Re)Associate the non-AP MLD and the AP MLD and share the sensing capabilities of links of the non-AP MLD, according to some embodiments.

[0048] FIG. 28 depicts an exemplary format of an enhanced (Re)Association Request frame and an enhanced (Re)Association Response frame transmitted by the affiliated STA of the MLD, according to some embodiments.

[0049] FIG. 29 depicts an exemplary process of sharing the sensing capabilities of links of the AP MLD and the non-AP MLD without association, according to some embodiments.

[0050] FIG. 30 depicts an exemplary enhanced Probe Request frame supporting the transmission of sensing information of the issuing non-AP MLD, according to some embodiments.

[0051] FIG. 31 depicts an exemplary WLAN sensing network including three MLDs, according to some embodiments.

[0052] FIG. 32 depicts an exemplary flowchart carried out by the AP MLD to share the sensing capabilities of the links of the AP MLD, according to some embodiments.

[0053] FIG. 33A and FIG. 33B depict an exemplary flowchart carried out by the AP MLD to perform disambiguation of the MLD identities for the WLAN sensing operation, according to some embodiments.DETAILED DESCRIPTION

[0054] Wireless sensing enables a device to obtain sensing measurements of the transmission channel(s) between two or more devices. With the execution of a wireless sensing procedure, it is possible for a device to obtain sensing measurements useful for detecting and tracking changes in the environment. In some aspects of what is described herein, a wireless sensing system may be used for a variety of wireless sensing applications by processing wireless signals (e.g., radio frequency (RF) signals) transmitted through a space between wireless communication devices. Example wireless sensing applications include motion detection, which can include the following: detecting motion of objects in space, motion tracking, breathing detection, breathing 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, breathing rate estimation, room occupancy detection, human dynamics monitoring, and other types of motion detection applications. Other examples of wireless sensing applications include object recognition, speaking recognition, keystroke detection and recognition, tamper detection, touch detection, attack detection, user authentication, driver fatigue detection, traffic monitoring, smoking detection, school safety issue detection, human counting, human recognition, bike localization, human queue estimation, Wi-Fi imaging, and other types of wireless sensing applications. For instance, the wireless sensing system may operate as a motion detection system to detect the existence and location of motion based on Wi-Fi signals or other types of wireless signals. As described in more detail below, a wireless sensing system may be configured to control measurement rates, wireless connections, and device participation, for example, to improve system operation or to achieve other technical advantages. The system improvements and technical advantages achieved when the wireless sensing system is used for motion detection are also achieved in examples where the wireless sensing system is used for another type of wireless sensing application.

[0055] In some example wireless sensing systems, a wireless signal includes a component (e.g., a synchronization preamble in a Wi-Fi PHY frame, or another type of component) that wireless devices can use to estimate a channel response or other channel information, 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 examples, a wireless sensing system can operate similarly to a bistatic radar system, where a Wi-Fi access point (AP) assumes the receiver role, and each Wi-Fi device (station (STA), node, or peer) connected to the AP assumes the transmitter role. The wireless sensing system may trigger a connected device to generate a transmission and produce a channel response measurement at a receiver device. This triggering process can be repeated periodically to obtain a sequence of time-variant measurements. A wireless sensing algorithm or a wireless sensing application may then receive the generated time-series of channel response measurements (e.g., computed by Wi-Fi receivers) as input, and through a correlation or filtering process, may then make a determination (e.g., determine if there is motion or no motion within the environment represented by the channel response, for example, based on changes or patterns in the channel estimations). In examples where the wireless sensing systemdetects motion, it may also be possible to identify a location of the motion within the environment based on motion detection results among a number of wireless devices.

[0056] Accordingly, wireless signals received at each of the wireless communication devices in a wireless communication network may be analyzed to determine channel information for the various communication links (between respective pairs of wireless communication devices) in the network. The channel information may be representative of a physical medium that applies a transfer function to wireless signals that traverse a space. In some instances, the channel information includes a channel response. Channel responses can characterize a physical communication path, representing the combined effect of, for example, scattering, fading, and power decay within the space between the transmitter and receiver. In some instances, the channel information includes beamforming state information (e.g., a feedback matrix, a steering matrix, channel state information, etc.) provided by a beamforming system. Beamforming is a signal processing technique often used in multi-antenna (multiple-input / multiple-output (MIMO)) radio systems for directional signal transmission or reception. Beamforming can be achieved by operating elements in an antenna array in such a way that signals at some angles experience constructive interference while others experience destructive interference.

[0057] The channel information for each of the communication links may be analyzed (e.g., by a hub device or other device in a wireless communication network, or by a sensing transmitter, sensing receiver, or sensing initiator communicably coupled to the network) to, for example, detect whether motion has occurred in the space, to determine a relative location of the detected motion or both. In some aspects, the channel information for each of the communication links may be analyzed to detect whether an object is present or absent, e.g., when no motion is detected in the space.

[0058] In some cases, a wireless sensing system can control a node measurement rate. For instance, a Wi-Fi motion system may configure variable measurement rates (e.g., channel estimation / environment measurement / sampling rates) based on criteria given by a current wireless sensing application (e.g., motion detection). In some implementations, when no motion is present or no motion is detected for a period of time, for example, the wireless sensing system can reduce the rate at which the environment is measured, such that the connected device will be triggered or caused to make sensing transmissions or sensing measurements less frequently. In some implementations, when motion is present, for example, the wireless sensing system can increase the triggering rate or sensing transmissions rate or sensing measurement rate to produce a time-series of measurements with finer time resolution. Controlling a variablesensing measurement rate can allow energy conservation (through the device triggering), reduce processing (less data to correlate or filter), and improve resolution during specified times.

[0059] In some cases, a wireless sensing system can perform band steering or client steering of nodes throughout a wireless network, for example, in a Wi-Fi multi -AP or extended service set (ESS) topology, multiple coordinating wireless APs each provide a basic service set (BSS) which may occupy different frequency bands and allow devices to transparently move from one participating AP to another (e.g., mesh). For instance, within a home mesh network, Wi-Fi devices can connect to any of the APs, but typically select one with good signal strength. The coverage footprints of the mesh APs typically overlap, often putting each device within the communication range of more than one AP. If the AP supports multi-bands (e.g., 2.4 GHz and 5 GHz), the wireless sensing system may keep a device connected to the same physical AP but instruct it to use a different frequency band to obtain more diverse information to help improve the accuracy or results of the wireless sensing application or sensing algorithm (e.g., motion detection algorithm). In some implementations, the wireless sensing system can change a device from being connected to one mesh AP to being connected to another mesh AP. Such device steering can be performed, for example, during wireless sensing (e.g., motion detection), based on criteria detected in a specific area to improve detection coverage or to better localize motion within an area.

[0060] In some cases, beamforming may be performed between wireless communication devices based on some knowledge of the communication channel (e.g., through feedback properties generated by a receiver), which can be used to generate one or more steering properties (e.g., a steering matrix) that are applied by a transmitter device to shape the transmitted beam / signal in a particular direction or directions. Thus, changes to the steering or feedback properties used in the beamforming process indicate changes, which may be caused by moving objects, in the space accessed by the wireless communication system. For example, motion may be detected by substantial changes in the communication channel, e.g., as indicated by a channel response, or steering or feedback properties, or any combination thereof, over a period of time.

[0061] In some implementations, for example, a steering matrix may be generated at a transmitter device (beamformer) based on a feedback matrix provided by a receiver device (beamformee) based on channel sounding. Because the steering and feedback matrices are related to the propagation characteristics of the channel, these matrices change as objects move within the channel. Changes in the channel characteristics are accordingly reflected in thesematrices, and by analyzing the matrices, motion can be detected, and different characteristics of the detected motion can be determined. In some implementations, a spatial map may be generated based on one or more beamforming matrices. The spatial map may indicate the general direction of an object in a space relative to a wireless communication device. In some cases, many beamforming matrices (e.g., feedback matrices or steering matrices) may be generated to represent a multitude of directions in which an object may be located relative to a wireless communication device. These many beamforming matrices may be used to generate the spatial map. The spatial map may be used to detect the presence of motion in the space or to detect the location of the detected motion.

[0062] In some instances, a motion detection system can control a variable device measurement rate in a motion detection process. For example, a feedback control system for a multi-node wireless motion detection system may adaptively change the sample rate based on environmental conditions. In some cases, such controls can improve the operation of the motion detection system or provide other technical advantages. For example, the measurement rate may be controlled in a manner that optimizes or otherwise improves air-time usage versus detection ability suitable for a wide range of different environments and different motion detection applications. The measurement rate may be controlled in a manner that reduces redundant measurement data to be processed, thereby reducing processor load / power requirements. In some cases, the measurement rate is controlled in a manner that is adaptive, for instance, an adaptive sample can be controlled individually for each participating device. An adaptive sample rate can be used with a tuning control loop for different use cases, or device characteristics.

[0063] In some cases, a wireless sensing system can allow devices to dynamically indicate and communicate their wireless sensing capability or wireless sensing willingness to the wireless sensing system. For example, there may be times when a device does not want to be periodically interrupted or triggered to transmit a wireless signal that would allow the AP to produce a channel measurement. For instance, if a device is sleeping, frequently waking the device up to transmit or receive wireless sensing signals could consume resources (e.g., causing a cell phone battery to discharge faster). These and other events could make a device willing or not willing to participate in wireless sensing system operations. In some cases, a cell phone running on its battery may not want to participate, but when the cell phone is plugged into a charger, it may be willing to participate. Accordingly, if the cell phone is unplugged, it may indicate to the wireless sensing system to exclude the cell phone from participating; whereas if the cell phone is plugged in, it may indicate to the wireless sensing system to include the cellphone in wireless sensing system operations. In some cases, if a device is under load (e.g., a device streaming audio or video) or busy performing a primary function, the device may not want to participate; whereas when the same device’s load is reduced and participating will not interfere with a primary function, the device may indicate to the wireless sensing system that it is willing to participate.

[0064] Example wireless sensing systems are described below in the context of motion detection (detecting motion of objects in the space, motion tracking, breathing detection, breathing 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, breathing rate estimation, room occupancy detection, human dynamics monitoring, and other types of motion detection applications). However, the operation, system improvements, and technical advantages achieved when the wireless sensing system is operating as a motion detection system are also applicable in examples where the wireless sensing system is used for another type of wireless sensing application.

[0065] In various embodiments of the disclosure, non-limiting definitions of one or more terms that will be used in the description are provided below.

[0066] A networking device is a device used in the WLAN network. For example, a multi-AP device or a STA device may be a networking device.

[0067] A wireless access point (WAP) or simply an access point (AP) is a networking device in a WLAN network that allows other networking devices in a WLAN network to connect to a wired network. For example, an AP creates a wireless local area network.

[0068] A station (STA) is any device that is connected to a WLAN network, and which contains 802.11 compliant MAC and PHY interfaces to the wireless medium. A STA may be a laptop, desktop, smartphone, or a smart appliance. A STA may be fixed, mobile, or portable. A STA that does not take on the role of an AP may be referred to as a non-AP STA.

[0069] A term “sensing space” may refer to any physical space in which a WLAN sensing system may operate.

[0070] A term “sensing area” may refer to a part or subset of a sensing space. For example, if a sensing space represents a house, then an individual room may be a sensing area within that sensing space.

[0071] A term “sensing procedure” may refer to a procedure that allows a high-efficiency (HE) STA or extremely high throughput (EHT) STA to perform sensing. A sensing procedure may be initiated with the establishment of a sensing measurement session, which may be followed by zero or more sensing measurement exchanges, and may be terminated either implicitly or explicitly with a sensing measurement session termination.

[0072] A term “sensing capabilities exchange” may refer to the beginning part of a sensing procedure, during which the sensing capabilities may be exchanged between the sensing STAs. A term “sensing capabilities exchange” may also be referred to as “sensing session setup” or “session setup”.

[0073] A term “sensing measurement session” may refer to a set of sensing measurement exchanges that use operational parameters agreed to between a sensing initiator and sensing responder and is identified by a Measurement Session ID. The term “sensing measurement session” may also be referred to as “sensing session” or “sensing measurement setup” or “measurement setup”. The term “Measurement Session ID” may also be referred to as “Measurement Setup ID”.

[0074] A term “sensing measurement exchange” may refer to the part of a sensing procedure during which sensing measurements are performed.

[0075] A term “sensing initiator” may refer to an HE STA or EHT STA that initiates a sensing procedure by transmitting a Sensing Measurement Request frame, or a Directional Multi-Gigabit (DMG) STA that initiates a DMG sensing procedure by transmitting a DMG Sensing Measurement Request frame.

[0076] A term “sensing responder” may refer to an HE STA or EHT STA that participates in a sensing procedure by responding to a sensing initiator, or a DMG STA that participates in a DMG sensing procedure by responding to a sensing initiator.

[0077] A term “sensing transmitter” may refer to a STA that transmits PPDUs used for measurements in a sensing procedure or a DMG sensing procedure.

[0078] A term “sensing receiver” may refer to a STA that is the intended recipient of PPDUs sent by a sensing transmitter to obtain sensing measurements in either a sensing procedure or a DMG sensing procedure.

[0079] A term “Proxy AP Client Device” (or “PACD”) may refer to a client device that can act as a proxy AP and initiate the forming of a WLAN sensing network among the client devices in the ESS.

[0080] A term “client device” (or “CD”) refers to a piece of software or hardware that requests and receives information or resources from a server. A client device is typically usedto access data, services, or applications provided by servers over a network, such as the internet. For example, client devices include smartphones, laptops, desktop computers, and other devices that may connect to the network and communicate with servers. A CD may be a networking device, non-AP STA, or Multi-AP device with a sensing agent (or sensing application) on it.

[0081] A term “sensing link” may refer to a link that traverses a sensing area of interest between two networking devices in a Wi-Fi network.

[0082] A term “normal client device” (or “NCD”) may refer to a client device which is not the proxy AP client device in an ESS.

[0083] A term “sensing pulse packet” may refer to a packet sent from the client device to its associated AP to indicate the client device's capability and status for sensing.

[0084] A term “BeaconSNR” may refer to the signal-to-noise ratio of the received Beacon frames, in dB. This may be time-averaged over recent history by a vendor-specific smoothing function (as defined in Table 6-7 — ESS Link Parameter Set of Draft P802.1 lREVme_D5.0).

[0085] A term “DataFrameSNR” may refer to the signal-to-noise ratio of the received Data frames, in dB. This may be time-averaged over recent history by a vendor-specific smoothing function (as defined in Table 6-7 — ESS Link Parameter Set of Draft P802.1 lREVme_D5.0).

[0086] A term “PACD capability” may refer to a capability to indicate if a client device could be a PACD.

[0087] A term “PACD capable device” may refer to a client device whose PACD capability value=1.

[0088] A term “current PACD status” may refer to a status to indicate if the client device is the current PACD.

[0089] A term “interference profile” may refer to the average noise plus interference power indicator. A medium access control (MAC) indication of the average noise plus interference power measured on a channel that meets the two simultaneous conditions: 1) the STA is not transmitting a frame, and 2) the STA is not receiving a frame addressed to it (as defined in 3.1 Definitions of Draft P802.11REVme_D5.0).

[0090] A term “current selected AP” may refer to an AP with most associated client devices in the ESS.

[0091] A term “median value indicator” may refer to an indicator to indicate the location of a median value in a list of values which are in an order from the smallest value to the largest value.

[0092] A term “current associated NCD” may refer to a normal client device associated with the current selected AP. A current associated NCD may be a normal client device associated with the current selected AP before PACD selection or a normal client device switched to the current selected AP before PACD selection for sensing.

[0093] A term “transmission opportunity (TXOP)” may refer to a negotiated interval of time during which a particular quality of service (QoS) station (e.g., a STA, an AP, or either a STA or an AP, for example, in the role of a sensing initiator, a sensing responder, a sensing transmitter or a sensing receiver) may have the right to initiate a frame exchange onto a wireless medium. A QoS access category (AC) of the transmission opportunity may be requested as part of a service or session negotiation.

[0094] A term “Quality of Service (QoS) access category (AC)” may refer to an identifier for a frame that classifies a priority of transmission that the frame requires. In an example, four QoS access categories are defined, namely AC VI: Video, AC_VO: Voice, AC_BE: Best-Effort, and AC BK: Background. Furthermore, each QoS access category may have different TXOP parameters defined for it.

[0095] A term “interframe space (IFS)” may refer to the time interval between certain adjacent PPDU (+SigExt (signal extension)). A STA shall determine that the medium is idle through the use of the Carrier Sense (CS) function for the interval specified. Different IFSs are defined to provide priority levels for access to the wireless medium. Timings for IFSs are referenced from the occurrence of the PHY interface primitives PHY-TXEND. confirm, PHY-TXSTART. confirm, PHY-RXSTART.indication, and PHY-RXEND. indication. One of the defined IFSs is a “short interframe space (SIFS)”. For example, a short interframe space may be approximately 10 ps. In another example, a short interframe space may be approximately 16 ps.

[0096] A term “PHY-layer Protocol Data Unit (PPDU)” may refer to a data unit that includes preamble and data fields. The preamble field may include transmission vector format information and the data field may include payload and higher layer headers.

[0097] A term “null data PPDU (NDP)” may refer to a PPDU that does not include a data field. In an example, a null data PPDU may be used for a sensing transmission, where a MAC header of the NDP includes information required for a sensing receiver to make a sensing measurement on the sensing transmission.

[0098] A term “transmission parameters” may refer to a set of IEEE 802.11 PHY transmitter configuration parameters that are defined as a part of a transmission vector(TXVECTOR) corresponding to a specific PHY and which may be configurable for each PHY -layer PPDU transmission or each NDP transmission.

[0099] A term “resource unit (RU)” may refer to an allocation of orthogonal frequency division multiplexing (OFDM) channels which may be used to carry a modulated signal. An RU may include a variable number of carriers depending on the mode of the modem.

[0100] A term “tone” may refer to an individual subcarrier in an OFDM signal. A tone may be represented in the frequency domain. In the frequency domain, a tone may also be referred to as a subcarrier.

[0101] A term “time domain pulse” may refer to a complex number that represents the amplitude and phase of discretized energy in the time domain. When frequency domain channel state information values are obtained for each tone from a baseband receiver, time domain pulses may be obtained by performing an Inverse Fast Fourier Transform (IFFT) on the channel state information values.

[0102] A term “sensing goal” may refer to a goal of a sensing activity at a time. A sensing goal is not static and may change at any time. For example, a sensing goal may require sensing measurements of a specific type, a specific format, or a specific precision, resolution, or accuracy to be available to a sensing application (or sensing algorithm).

[0103] A term “wireless local area network (WLAN) sensing session” or “Wi-Fi sensing session” may refer to a period during which objects in a physical space may be probed, detected and / or characterized. For example, during a WLAN sensing session, several devices participate in and thereby contribute to the generation of sensing measurements. A WLAN sensing session may be referred to as a “measurement campaign”.

[0104] A term “non-sensing message” may refer to a message which is not primarily related to sensing. For example, non-sensing messages may include data, management, and control messages.

[0105] A term “sensing measurement” may refer to a measurement of the state of a wireless channel between a transmitter device (for example, a sensing transmitter) and a receiver device (for example, a sensing receiver) derived from a sensing transmission. For example, sensing measurement may also be referred to as channel response measurement.

[0106] A term “sensing application” may refer to a computational algorithm that achieves a sensing goal. A sensing application may be executed on any device in a WLAN sensing system. In an example, sensing application may also be referred to as sensing algorithm.

[0107] Wireless network management (WNM) may provide information on network conditions and may also provide a means to obtain and exchange WLAN sensing information.

[0108] A sensing receiver is a STA that receives sensing transmissions (for example, PPDUs or any other transmission including 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.

[0109] A sensing transmitter is a STA that transmits a sensing transmission (for example, PPDUs or any other transmission) used for sensing measurements (for example, channel state information) in a WLAN sensing procedure. In an example, a STA is an example of a sensing transmitter. In some examples, an AP may be a sensing transmitter for WLAN sensing purposes, for example where a STA acts as a sensing receiver.

[0110] A sensing initiator is a STA that initiates a WLAN sensing procedure. The role of the sensing initiator may be taken on by a sensing receiver, a sensing transmitter, or a separate device that includes a sensing application (for example, a remote processing device).

[0111] A sensing responder is a STA that participates in a WLAN sensing procedure initiated by a sensing initiator. The role of the sensing responder may be taken on by a sensing receiver or a sensing transmitter. For example, multiple sensing responders may take part in a WLAN sensing session.

[0112] A sensing by proxy (SBP) initiator is defined as a non-AP STA acting as a sensing initiator that transmits an SBP Request frame. For example, sensing by proxy enables a non-AP STA to obtain sensing measurements of the channel between an AP and one or more non-AP STAs or between a receiving antenna and a transmitting antenna of an AP. With the execution of the SBP procedure, it is possible for a non-AP STA to obtain sensing measurements necessary for detecting and tracking changes in the environment. An SBP responder is an AP that receives or is the intended recipient of an SBP Request frame.

[0113] A term “sensing transmission” may refer to a transmission made from a sensing transmitter to a sensing receiver which may be used to make a sensing measurement. In an example, a sensing transmission may also be referred to as a wireless sensing signal or a wireless signal.

[0114] A 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.

[0115] A term “sensing response message” may refer to a message which is included within a sensing transmission from a sensing transmitter to a sensing receiver. A sensing transmission that includes a sensing response message may be used by a sensing receiver to perform a sensing measurement.

[0116] A term “sensing response announcement” may refer to a message that is included 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 NDP A. In examples, a sensing response NDP may be transmitted using a requested transmission configuration.

[0117] A term “sensing response NDP” may refer to a response transmitted by a sensing transmitter and used for a sensing measurement at a sensing receiver. In examples, a sensing response NDP may be used when a requested transmission configuration is incompatible with transmission parameters required for successful non-sensing message reception. A sensing response NDP may be announced by a sensing response announcement. In an example, a sensing response NDP may be implemented with a null data PPDU. In some examples, a sensing response NDP may be implemented with a frame that does not contain any data.

[0118] A term “channel representation information (CRI)” or “channel impulse response (CIR)” may refer to properties of a communications channel, such as how wireless signals propagate from a sensing transmitter to a sensing receiver along multiple paths, which are known or measured by a technique of channel estimation. For example, CRI may refer to one or more sensing measurements made on one or more sensing transmissions during a sampling instance which together represent the state of the channel at the sampling instance between two devices.

[0119] A term “channel state information (CSI)” may refer to an example of CRI which is represented in the frequency domain. CSI indicates the properties of a communications channel which is measured by channel estimation in subcarrier-level granularity. CSI is typically a matrix of complex values representing the amplitude attenuation and phase shift of signals, which provides an estimation of a communications channel. A CSI of a subcarrier may be represented as an in-phase (real) component (I) and a quadrature (imaginary) component (Q).

[0120] A term “time-domain channel representation information (TD-CRI)” or “channel impulse response (CIR)” in time-domain may refer to an example of CRI that is represented in the time domain. TD-CRI may be generated by applying an inverse transform, such as an Inverse Discrete Fourier Transform (IDFT) or an IFFT, to CSI. TD-CRI or CIR of a time domain pulse may be represented as an in-phase (real) component (I) and a quadrature (imaginary) component (Q).

[0121] A term “full time-domain channel representation information (full TD-CRI)” may refer to a series of complex pairs of time-domain pulses which are created by performing an IFFT on CSI values, for example, CSI calculated by a baseband receiver.

[0122] A term “filtered time-domain channel representation information (filtered TD-CRI)” may refer to a reduced series of complex pairs of time-domain pulses created by applying an algorithm to a full TD-CRI. The algorithm may select some time domain pulses and reject others. The filtered TD-CRI may contain information that relates a selected time domain pulse to the corresponding time domain pulse in the full TD-CRI.

[0123] A term “reconstructed filtered time-domain channel representation information (reconstructed filtered TD-CRI)” may refer to a version of a full TD-CRI created from a filtered TD-CRI.

[0124] A term “channel representation information transmission message” may refer to a message sent by a sensing receiver that has performed a sensing measurement on a sensing transmission, in which the sensing receiver sends CRI to a sensing initiator which may be a sensing transmitter that contains a sensing application or a remote processing device which contains a sensing application.

[0125] A term “reconstructed CSI (R-CSI)” may refer to a representation of original CSI values as measured by the baseband receiver that is reconstructed from a time domain channel representation information (TD-CRI). In an example, R-CSI may be calculated by taking original CSI values (in the frequency domain), performing an IFFT to translate those values into the time domain, selecting a number of time domain pulses, zeroing or nulling time domain values that do not include a selected time domain pulse, and performing a Fast Fourier Transform (FFT). The resulting frequency domain complex values are the R-CSI.

[0126] A term “feature of interest” may refer to an item or state of an item in a sensing space that is positively detected and / or identified by a sensing application.

[0127] A term “sensing imprint” may refer to a steady state or semi-static representation of the propagation channel between a sensing transmitter and a sensing receiver in the sensing space calculated by the sensing receiver in the form of a time domain channel impulse response.

[0128] A term “requested transmission configuration” may refer to transmission parameters a sensing transmitter is requested to use when sending a sensing transmission.

[0129] A term “delivered transmission configuration” may refer to transmission parameters applied by a sensing transmitter to a sensing transmission.

[0130] A term “imprint delta” may refer to a single dimension matrix of complex values which represent the difference between a time domain channel impulse response generated by converting a CSI measurement to the time domain using an IFFT, and a stored sensing imprint.

[0131] A term “measurement imprint delta threshold” may refer to a minimum difference between a TD-CRI value and the corresponding sensing imprint value for which a sensingreceiver or a sensing application considers that there is a change in the propagation channel propagation characteristics.

[0132] A term “measurement imprint delta count” may refer to the number of times which a measurement imprint delta threshold is exceeded before a sensing receiver, or a sensing application considers that there is a change in propagation channel propagation characteristics.

[0133] A term “imprint delta derivative period” may refer to a period during which imprint delta derivatives must remain below an imprint delta derivative threshold before a sensing receiver or a sensing application may determine that a new sensing imprint needs to be calculated.

[0134] A term “imprint delta derivative” may refer to a rate of change of the imprint delta over one or more tones and over one or more frames.

[0135] A term “imprint delta derivative threshold” may refer to a minimum value of the imprint delta derivative for which a sensing receiver or a sensing application considers that there is ongoing movement or motion in the sensing space. If the imprint delta derivative drops below the imprint delta derivative threshold, a sensing receiver or a sensing application may determine that a new sensing imprint needs to be calculated.

[0136] A term “steady-state imprint delta threshold” may refer to a maximum difference between a TD-CRI value and a corresponding sensing imprint value for which a sensing receiver or a sensing application considers that the TD-CRI has not returned to its steady-state (e.g., a stored sensing imprint).

[0137] A term “sensing imprint average count” may refer to a number of sensing measurements which may be averaged to generate a sensing imprint.

[0138] A term “steering matrix configuration” may refer to a matrix of complex values representing real and complex phases required to pre-condition one or more antennas of a radio frequency (RF) transmission signal chain for each transmit signal. Application of a steering matrix configuration (for example, by a spatial mapper) enables beamforming and beamsteering.

[0139] A term “spatial mapper” may refer to a signal processing element that adjusts the amplitude and phase of a signal input to an RF transmission chain in a sensing transmitter. A spatial mapper may include elements to process the signal to each RF chain implemented. The operation carried out may be called spatial mapping. The output of a spatial mapper is one or more spatial streams.

[0140] A mesh network or a wireless mesh network may refer to a communications network (e.g., WLAN) made up of radio nodes (e.g., mesh stations or mesh STAs, mesh clients,or Multi-AP devices, etc.) organized in a mesh topology. For example, the mesh network may also be referred to as “Mesh”.

[0141] A sensing controller is a controller that facilitates and coordinates WLAN sensing-related connections and activities.

[0142] A Multi-AP device may refer to a physical device of a mesh network that may act as both a station and an AP or a device that has a Backhaul STA module for backhaul link connection and a Fronthaul AP module for a fronthaul link connection.

[0143] A term “Multi-AP Network” or “Multi-AP Network Deployment”, or “Mesh BSS” may refer to a collection of interconnected physical devices.

[0144] A term “mesh root node” may refer to a multi- AP device with a Multi-AP controller in a mesh network. For example, a backhaul of the mesh root node is connected to a wide area network (WAN).

[0145] A term “leaf node” may refer to a multi-AP device without a multi-AP controller in the mesh network. The leaf node may connect to the mesh root node directly or via other leaf nodes.

[0146] A term “hop” in a mesh network may refer to a backhaul connection between two multi-AP devices.

[0147] A term “mesh network configuration option (MNCO)” may refer to a possible way to configure backhaul links in the mesh network.

[0148] A term “sensing preferred MNCO” may refer to an MNCO that is best suited or adequately suited to sensing according to one or more established criteria. For example, a sensing preferred MNCO must also be adequately suited for data communications.

[0149] A term “preferred sensing link” may refer to a link that traverses a sensing area of interest between two multi-AP devices in a mesh network. For example, the preferred sensing link may be determined by a sensing application or a sensing controller to be the best sensing link by some criteria.

[0150] A term “sensing PPDU” may refer to a customized data packet with one or more training fields on which sensing measurements can be made and a header and data field portion which contain Motion Information elements to be shared with other networked devices in the Wi-Fi network.

[0151] A term “Basic Service Set (BSS)” may refer to a collection of an AP STA and non-AP STAs which are associated together at the PHY / MAC layer to form a wireless network. The BSS includes a single STA acting as an AP (or AP STA) and one or more STAs (non-AP STA, or simply STA where the access point is referred to as AP) connected to and controlledby the AP device. A STA that is associated with an AP is equivalently considered to be connected to and controlled by the AP. A BSS is identified in IEEE 802.11 by a BSSID.

[0152] A term “Out-of-BSS (OBSS)” may be used by IEEE P802.11bf to describe communications between STAs that are not part of a BSS (and that may or may not be part of an ESS). In the case of WLAN sensing, OBSS may describe sensing messages and sensing transmissions made between STAs that are not part of a BSS, but which may generate useful sensing measurements.

[0153] A term “Basic Service Area (BSA)” may refer to an area including the members of the BSS. The BSA may also include members of other BSSs.

[0154] A term “Traffic Category (TC)” may refer to a label for medium access control service data units that have a distinct user priority (UP), as viewed by higher layer entities, relative to other MAC Service Data Units (MSDUs) provided for delivery over the same link. The TCs are meaningful only to MAC entities that support the quality of service within the MAC data service. The MAC entities determine the UP for MSDUs belonging to a particular traffic category using the priority value provided with those MSDUs at the MAC service access point.

[0155] A term “Traffic Classification (TCLAS)” may refer to a specification of one of multiple types of matching filters to classify protocol data units or medium access control service data units as belonging to a particular traffic stream. Depending on the type of classification, the filter is applied within the MAC sublayer management entity, above the MAC, or within the MAC itself.

[0156] A term “Traffic Identifier (TID)” may refer to any identifier used by higher layer entities to distinguish between medium access control service data units and MAC entities that support quality of service within the MAC data service. There are 16 possible TID values; eight identify traffic categories, and the other eight identify parameterized traffic streams. The TID is assigned to an MSDU in the layers above the MAC.

[0157] A term “Traffic Specification (TSPEC)” may refer to quality-of-service characteristics of a data flow to and from a QoS station.

[0158] A term “Traffic Stream (TS)” may refer to a set of medium access control service data units to be delivered subject to the quality-of-service parameter values provided to the MAC in a particular traffic specification. TSs are meaningful only to MAC entities that support QoS within the MAC data service. These MAC entities determine the TSPEC applicable for the delivery of MSDUs belonging to a particular TS using the priority parameter provided with those MSDUs at the MAC service access point.

[0159] A term “Traffic Stream Identifier (TSID)” may refer to any of the identifiers usable by higher layer entities to distinguish medium access control service data units from MAC entities for parameterized quality of service (e.g., the traffic stream with a particular traffic specification) within the MAC data service. The TSID is assigned to an MSDU in the layers above the MAC.

[0160] A term “Unassociated Sensing Measurement Session” may refer to a sensing measurement session established between an AP and a Non-AP STA that is not currently associated with the AP.

[0161] A term “User Priority (UP)” may refer to a value associated with a medium access control service data unit that indicates how the MSDU is to be handled. The UP is assigned to an MSDU in the layers above the MAC.

[0162] A term “Link Identifier (ID)” or “Link ID” may refer to a unique identifier of a link of multiple links on a Multi-Link Device (MLD). The Link ID may be associated with a STA (an AP STA or a non-AP STA) on the MLD.

[0163] A term “Link Group ID” may refer to a unique identifier of a group of links on the MLD. Each link in the group of links traverses the same physical channel (but not necessarily the same propagation channel) and so may be used to make a sensing measurement of that physical channel.

[0164] A term “propagation channel” may refer to characteristics of a channel through which a signal passes from a transmitter to a receiver (e.g., a sensing transmitter and a sensing receiver). For example, the propagation channel of a higher-frequency signal may be shorter or may have greater impedance due to the characteristics of the signal, modulation, etc.

[0165] For purposes of reading the description of the various embodiments below, the following descriptions of the sections of the specifications and their respective contents may be helpful:

[0166] Section A describes a wireless communications system, wireless transmissions, and sensing measurements which may be useful for practicing embodiments described herein.

[0167] Section B describes systems and methods that are useful for a wireless sensing system configured to send sensing transmissions and make sensing measurements.

[0168] Section C describes embodiments of systems and methods that are useful to perform disambiguation of the MLD identities for WLAN sensing operation.A. Wireless communications system, wireless transmissions, and sensing measurements

[0169] FIG. 1 illustrates wireless communication system 100. Wireless communication system 100 includes three wireless communication devices: first wireless communication device 102A, second wireless communication device 102B, and third wireless communication device 102C. 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.).

[0170] Wireless communication devices 102A, 102B, 102C can operate in a wireless network, for example, according to 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 according to one or more of the 802.11 family of standards developed by IEEE (e.g., Wi-Fi networks), and others. Examples of PANs include networks that operate according to short-range communication standards (e.g., Bluetooth®, Near Field Communication (NFC), ZigBee), millimeter wave communications, and others.

[0171] In some implementations, 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 Enhanced General Packet Radio Service (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 LTE-Advanced (LTE-A); 5G standards, and others.

[0172] In the example shown in FIG. 1, wireless communication devices 102A, 102B, 102C can be or may include standard wireless network components. For example, wireless communication devices 102A, 102B, 102C may be commercially available Wi-Fi APs or another type of wireless access point (WAP) performing one or more operations as described herein that are embedded as instructions (e.g., software or firmware) in the modem of the WAP. In some cases, wireless communication devices 102A, 102B, 102C may be nodes of a wireless mesh network, such as, for example, a commercially available mesh network system (e.g.,Plume Wi-Fi, Google Wi-Fi, Qualcomm Wi-Fi SON, etc.). In some cases, wireless communication devices 102A, 102B, 102C acting as nodes of a mesh network system may adhere to a mesh networking standard such as Wi-Fi Alliance Easy Mesh or IEEE P802.1 Is. In some cases, another type of standard or conventional Wi-Fi transmitter device may be used. In some instances, one or more of wireless communication devices 102A, 102B, 102C may be implemented as WAPs in a mesh network, while other wireless communication device(s) 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 wireless communication devices 102A, 102B, 102C is a mobile device (e.g., a smartphone, a smartwatch, a tablet, a laptop computer, etc.), a wireless-enabled device (e.g., a smart thermostat, a Wi-Fi enabled camera, a smart TV), or another type of device that communicates in a wireless network. In some cases, one or more wireless communication devices 102A, 102B, 102C may be Multi-Link Devices (MLDs). In some embodiments, MLDs refer to systems or components that can establish and manage multiple communication links or connections simultaneously.

[0173] Wireless communication devices 102A, 102B, 102C may be implemented without Wi-Fi components; for example, other types of standard or non-standard wireless communication may be used for motion detection. In some cases, wireless communication devices 102A, 102B, 102C can be, or they may be part of, a dedicated motion detection system. For example, a dedicated motion detection system can include a hub device and one or more beacon devices (as remote sensor devices), and wireless communication devices 102A, 102B, 102C can be either a hub device or a beacon device in the motion detection system.

[0174] As shown in FIG. 1, wireless communication device 102C includes modem 112, processor 114, memory 116, and power unit 118; any of wireless communication devices 102A, 102B, 102C in wireless communication system 100 may include the same, additional, or different components and the components may be configured to operate as shown in FIG. 1 or in another manner. In some implementations, modem 112, processor 114, memory 116, and power unit 118 of a wireless communication device are housed together in a common housing or other assembly. In some implementations, one or more of the components of a wireless communication device can be housed separately, for example, in a separate housing or other assembly.

[0175] Modem 112 can communicate (receive, transmit, or both) wireless signals. For example, modem 112 may be configured to communicate RF signals formatted according to a wireless communication standard (e.g., Wi-Fi or Bluetooth). Modem 112 may be implementedas the example wireless network modem 112 shown in FIG. 1 or may be implemented in another manner, for example, with other types of components or subsystems. In some implementations, modem 112 includes a radio subsystem and a baseband subsystem. In some cases, the baseband subsystem and radio subsystem can be implemented on a common chip or chipset, or they may be implemented in a card or another type of assembled device. The baseband subsystem can be coupled to the radio subsystem, for example, by leads, pins, wires, or other types of connections.

[0176] In some cases, a radio subsystem in modem 112 can include one or more antennas and RF circuitry. The RF circuitry can include, for example, circuitry that filters, amplifies, or otherwise conditions analog signals, circuitry that up-converts baseband signals to RF signals, circuitry that down-converts RF signals to baseband signals, etc. Such circuitry may include, for example, filters, amplifiers, mixers, a local oscillator, etc. The radio subsystem can be configured to communicate radio frequency wireless signals on the wireless communication channels. As an example, the radio subsystem may include a radio chip, an RF front end, and one or more antennas. A radio subsystem may include additional or different components. In some implementations, the radio subsystem can be or may include the radio electronics (e.g., RF front end, radio chip, or analogous components) from a conventional modem, for example, from a Wi-Fi modem, pico base station modem, etc. In some implementations, the antenna includes multiple antennas.

[0177] In some cases, a baseband subsystem in modem 112 can include, for example, digital electronics configured to process digital baseband data. As an example, the baseband subsystem may include a baseband chip. A 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 the radio subsystem, to communicate wireless network traffic through the radio subsystem, to detect motion based on motion detection signals received through the radio subsystem, or to perform other types of processes. For instance, the baseband subsystem may include one or more chips, chipsets, or other types of devices that are configured to encode signals and deliver the encoded signals to the radio subsystem for transmission or to identify and analyze data encoded in signals from the radio subsystem (e.g., by decoding the signals according to a wireless communication standard, by processing the signals according to a motion detection process, or otherwise).

[0178] In some instances, the radio subsystem in modem 112 receives baseband signals from the baseband subsystem, up-converts the baseband signals to RF signals, and wirelesslytransmits the RF signals (e.g., through an antenna). In some instances, the radio subsystem in modem 112 wirelessly receives RF signals (e.g., through an antenna), down-converts the RF to baseband signals, and sends the baseband signals to the baseband subsystem. The signals exchanged between the radio subsystem and the baseband subsystem may be digital or analog signals. In some examples, the baseband subsystem includes conversion circuitry (e.g., a digital-to-analog converter, an analog-to-digital converter) and exchanges analog signals with the radio subsystem. In some examples, the radio subsystem includes conversion circuitry (e.g., a digital-to-analog converter, an analog-to-digital converter) and exchanges digital signals with the baseband subsystem.

[0179] In some cases, the baseband subsystem of modem 112 can communicate 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 may also transmit or receive (or both) signals (e.g., motion probe signals or motion detection signals) through the radio subsystem on a dedicated wireless communication channel. In some instances, the baseband subsystem generates motion probe signals for transmission, for example, to probe a space for motion. In some instances, the baseband subsystem processes the received motion detection signals (signals based on motion probe signals transmitted through the space), for example, to detect the motion of an object in a space.

[0180] Processor 114 can execute instructions, for example, to generate output data based on data inputs. The instructions can include programs, codes, scripts, or other types of data stored in memory 116. Additionally, or alternatively, the instructions can be encoded as preprogrammed or re-programmable logic circuits, logic gates, or other types of hardware or firmware components. Processor 114 may be or may include a general-purpose microprocessor, a specialized co-processor, or another type of data processing apparatus. In some cases, processor 114 performs high-level operation of the wireless communication device 102C. For example, processor 114 may be configured to execute or interpret software, scripts, programs, functions, executables, or other instructions stored in memory 116. In some implementations, processor 114 may be included in modem 112.

[0181] Memory 116 can include computer-readable storage media, for example, a volatile memory device, a non-volatile memory device, or both. Memory 116 can 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 instances, one or more components of the memory can be integrated or otherwise associated with another component of wireless communication device 102C. Memory 116 may store instructions that areexecutable by processor 114. For example, the instructions may include instructions for timealigning signals using an interference buffer and a motion detection buffer, such as through one or more of the operations of the example processes herein disclosed.

[0182] Power unit 118 provides power to the other components of wireless communication device 102C. For example, the other components may operate based on electrical power provided by power unit 118 through a voltage bus or other connection. In some implementations, power unit 118 includes a battery or a battery system, for example, a rechargeable battery. In some implementations, power 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 conditioned for a component of wireless communication device 102C. Power unit 118 may include other components or may operate in another manner.

[0183] In the example shown in FIG. 1, wireless communication devices 102A, 102B transmit wireless signals (e.g., according to a wireless network standard, a motion detection protocol, or otherwise). For instance, wireless communication devices 102A, 102B may broadcast wireless motion probe signals (e.g., reference signals, beacon signals, status signals, etc.), or they may send wireless signals addressed to other devices (e.g., a user equipment, a client device, a server, etc.), and the other devices (not shown) as well as 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, for example, according to a wireless communication standard or otherwise.

[0184] In the example shown, wireless communication device 102C processes the wireless signals from wireless communication devices 102A, 102B to detect the motion of an object in a space accessed by the wireless signals, to determine the location of the detected motion, or both. For example, wireless communication device 102C may perform one or more operations of the example processes described below with respect to FIG. 32, FIG. 33A and FIG. 33B, or another type of process for detecting motion or determining a location of detected motion. The space accessed by the wireless signals can be an indoor or outdoor space, which may include, for example, one or more fully or partially enclosed areas, an open area without enclosure, etc. The space can be or can include an interior of a room, multiple rooms, a building, or the like. In some cases, the wireless communication system 100 can be modified, for instance, such that wireless communication device 102C can transmit wireless signals, and wirelesscommunication devices 102A, 102B can process the wireless signals from wireless communication device 102C to detect motion or determine a location of detected motion.

[0185] The wireless signals used for motion detection can include, for example, a beacon signal (e.g., Bluetooth Beacons, Wi-Fi Beacons, other wireless beacon signals), another standard signal generated for other purposes according to a wireless network standard, or nonstandard signals (e.g., random signals, reference signals, etc.) generated for motion detection or other purposes. For example, motion detection may be carried out by analyzing one or more training fields carried by the wireless signals or by analyzing other data carried by the signal. In some examples data may be added for the express purpose of motion detection or the data used may nominally be for another purpose and may be reused or repurposed for motion detection. In some examples, the wireless signals propagate through an object (e.g., a wall) before or after interacting with a moving object, which may allow the moving object's movement to be detected without an optical line-of-sight between the moving object and the transmission or receiving hardware. Based on the received signals, wireless communication device 102C may generate motion detection data. In some instances, wireless communication device 102C may communicate 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, building, outdoor area, etc.

[0186] In some implementations, wireless communication devices 102A, 102B can be modified to transmit motion probe signals (which may include, e.g., a reference signal, beacon signal, or another signal used to probe a space for motion) on a separate wireless communication channel (e.g., a frequency channel or coded channel) from wireless network traffic signals. For example, the modulation applied to the payload of a motion probe signal and the type of data or data structure in the payload may be known by wireless communication device 102C, which may reduce the amount of processing that wireless communication device 102C performs for motion sensing. The header may include additional information such as, for example, an indication of whether motion was detected by another device in wireless communication system 100, an indication of the modulation type, an identification of the device transmitting the signal, etc.

[0187] In the example shown in FIG. 1, wireless communication system 100 is a wireless network, with wireless communication links between each of wireless communication devices 102. In the example shown, the wireless communication link between wireless communication device 102C and wireless communication device 102A can be used to probe motion detection field 110A, the wireless communication link between wireless communication device 102Cand wireless communication device 102B can be used to probe motion detection field 110B, and the wireless communication link between wireless communication device 102A and wireless communication device 102B can be used to probe motion detection field 110C. In some instances, each wireless communication device 102 detects motion in motion detection fields 110 accessed by that device by processing received signals that are based on wireless signals transmitted by wireless communication devices 102 through motion detection fields 110. For example, when person 106 shown in FIG. 1 moves in motion detection field 110A and motion detection field 1 IOC, wireless communication devices 102 may detect the motion based on signals they receive that are based on wireless signals transmitted through respective motion detection fields 110. For instance, wireless communication device 102A can detect the motion of person 106 in motion detection fields 110A, 110C, wireless communication device 102B can detect the motion of person 106 in motion detection field 110C, and wireless communication device 102C can detect the motion of person 106 in motion detection field 110A.

[0188] In some instances, motion detection fields 110 can include, for example, air, solid materials, liquids, or another medium through which wireless electromagnetic signals may propagate. In the example shown in FIG. 1, 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 from or shared with the wireless communication channel for network traffic) are used to detect the movement of an object in a space. The objects can be any type of static or moveable object and can be living or inanimate. For example, the object can be a human (e.g., person 106 shown in FIG. 1), an animal, an inorganic object, or another device, apparatus, or assembly, an object that defines all or part of the boundary of a space (e.g., a wall, door, window, etc.), or another type of object. In some implementations, motion information from the wireless communication devices may be analyzed to determine a location of the detected motion. For example, as described further below, one of wireless communication devices 102 (or another device communicably coupled to wireless communications devices 102) may determine that the detected motion is near a particular wireless communication device.

[0189] FIG. 2A and FIG. 2B are diagrams showing example wireless signals communicated between wireless communication devices 204A, 204B, 204C. Wireless communication devices 204A, 204B, 204C can be, for example, wireless communication devices 102A, 102B, 102C shown in FIG. 1, or other types of wireless communication devices. Wireless communication devices 204A, 204B, 204C transmit wireless signals through space 200. Space 200 can be completely or partially enclosed or open at one or more boundaries. In an example, space 200 may be a sensing space. Space 200 can be or can include an interior of a room, multiple rooms, a building, an indoor area, an outdoor area, or the like. First wall 202A, second wall 202B, and third wall 202C at least partially enclose space 200 in the example shown.

[0190] In the example shown in FIG. 2A and FIG. 2B, wireless communication device 204A is operable to transmit wireless signals repeatedly (e.g., periodically, intermittently, at scheduled, unscheduled or random intervals, etc.). Wireless communication devices 204B, 204C are operable to receive signals based on those transmitted by wireless communication device 204A. Wireless communication devices 204B and 204C each have a modem (e.g., modem 112 shown in FIG. 1) that is configured to process received signals to detect motion of an object in space 200.

[0191] As shown, an object is in first position 214A in FIG. 2 A, and the object has moved to second position 214B in FIG. 2B. In FIG. 2A and FIG. 2B, the moving object in space 200 is represented as a human, but the moving object can be another type of object. For example, the moving object can be an animal, an inorganic object (e.g., a system, device, apparatus, or assembly), an object that defines all or part of the boundary of space 200 (e.g., a wall, door, window, etc.), or another type of object.

[0192] As shown in FIG. 2A and FIG. 2B, multiple example paths of the wireless signals transmitted from wireless communication device 204A are illustrated by dashed lines. Along first signal path 216, the wireless signal is transmitted from wireless communication device 204A and reflected off first wall 202A toward wireless communication device 204B. Along second signal path 218, the wireless signal is transmitted from the wireless communication device 204A and reflected off second wall 202B and first wall 202A toward wireless communication device 204C. Along third signal path 220, the wireless signal is transmitted from wireless communication device 204A and reflected off second wall 202B toward wireless communication device 204C. Along fourth signal path 222, the wireless signal is transmitted from wireless communication device 204A and reflected off third wall 202C toward wireless communication device 204B.

[0193] In FIG. 2A, along fifth signal path 224A, the wireless signal is transmitted from wireless communication device 204A and reflected off the object at first position 214A toward wireless communication device 204C. Between FIG. 2A and FIG. 2B, a surface of the object moves from first position 214A to second position 214B in space 200 (e.g., some distance away from first position 214A). In FIG. 2B, along sixth signal path 224B, the wireless signal is transmitted from wireless communication device 204 A and reflected off the object at second position 214B toward wireless communication device 204C. Sixth signal path 224B depicted in FIG. 2B is longer than fifth signal path 224A depicted in FIG. 2A due to the movement of the object from first position 214A to second position 214B. In some examples, a signal path can be added, removed, or otherwise modified due to the movement of an object in a space.

[0194] The example wireless signals shown in FIG. 2A and FIG. 2B may experience attenuation, frequency shifts, phase shifts, or other effects through their respective paths and may have portions that propagate in another direction, for example, through the first, second, and third walls 202A, 202B, and 202C. In some examples, the wireless signals are radio frequency (RF) signals. The wireless signals may include other types of signals.

[0195] In the example shown in FIG. 2A and FIG. 2B, wireless communication device 204A can repeatedly transmit a wireless signal. In particular, FIG. 2A shows the wireless signal being transmitted from wireless communication device 204A at a first time, and FIG. 2B shows the same wireless signal being transmitted from wireless communication device 204A at a second, later time. The transmitted signal can be transmitted continuously, periodically, at random or intermittent times, or the like, or a combination thereof. The transmitted signal can have a number of frequency components in a frequency bandwidth. The transmitted signal can be transmitted from wireless communication device 204A in an omnidirectional manner, in a directional manner, or otherwise. In the example shown, the wireless signals traverse multiple respective paths in space 200, and the signal along each path may become attenuated due to path losses, scattering, reflection, or the like and may have a phase or frequency offset.

[0196] As shown in FIG. 2A and FIG. 2B, the signals from first to sixth paths 216, 218, 220, 222, 224A, and 224B combine at wireless communication device 204C and wireless communication device 204B to form received signals. Because of the effects of the multiple paths in space 200 on the transmitted signal, space 200 may 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 space 200, the attenuation or phase offset affected by a signal in a signal path can change, and hence, the transfer function of space 200 can change. Assuming the same wireless signal is transmitted from wireless communication device 204A, if thetransfer function of space 200 changes, the output of that transfer function - the received signal - will also change. A change in the received signal can be used to detect the movement of an object.

[0197] Mathematically, a transmitted signal (t) transmitted from the first wireless communication device 204A may be described according to Equation (1): / ■(t) = n=-oo CneJa)nt.... (1)

[0198] where )nrepresents the frequency of the / 7th frequency component of the transmitted signal, cnrepresents the complex coefficient of the / 7th frequency component, and t represents time. With the f(t) being transmitted from the first wireless communication device 204 A, an output signal rk(t) from a path, k. may be described according to Equation (2):

[0199] where an krepresents an attenuation factor (or channel response; e.g., due to scattering, reflection, and path losses) for the / 7th frequency component along k. and <pn krepresents the phase of the signal for the / 7th frequency component along k. Then, the received signal, 7?, at a wireless communication device can be described as the summation of all output signals rk(t) from all paths to the wireless communication device, which is shown in Equation (3).R = Ik ■■■ ■ (3)

[0200] Substituting Equation (2) into Equation (3) renders the following Equation (4).

[0201] 7? at a wireless communication device can then be analyzed. 7? at a wireless communication device can be transformed to the frequency domain, for example, using a Fast Fourier Transform (FFT) or another type of algorithm. The transformed signal can represent 7? as a series of n complex values, one for each of the respective frequency components (at the n frequencies u>„). For a frequency component at frequency a>n. a complex value, Hn. may be represented as follows in Equation (5).n Sfc

[0202] Hnfor a given a>nindicates a relative magnitude and phase offset of the received signal at con. When an object moves in the space, Hnchanges due to an kof the space changing. Accordingly, a change detected in the channel response can be indicative of the movement of an object within the communication channel. In some instances, noise, interference, or other phenomena can influence the channel response detected by the receiver, and the motion detection system can reduce or isolate such influences to improve the accuracy and quality ofmotion detection capabilities. In some implementations, the overall channel response can be represented as follows in Equation (6).

[0203] In some instances, the channel response, hch, for a space can be determined, for example, based on the mathematical theory of estimation. For instance, a reference signal, Rref, can be modified with a candidate hch, and then a maximum likelihood approach can be used to select the candidate channel which gives the best match to the received signal (RrcVd)- Insome cases, an estimated received signal (RrcVd) is obtained from the convolution of Rref with the candidate hch, and then the channel coefficients of hchare varied to minimize the squared error of RrcVd- This can be mathematically illustrated as follows in Equation (7):

[0204] with the optimization criterion as in Equation (8).mill fhCh1

[0205] The minimizing, or optimizing, process can utilize an adaptive filtering technique, such as least mean squares (LMS), recursive least squares (RLS), batch least squares (BLS), etc. The channel response can be a finite impulse response (FIR) filter, infinite impulse response (IIR) filter, or the like. As shown in the equation above, the received signal can be considered as a convolution of the reference signal and the channel response. The convolution operation means that the channel coefficients possess a degree of correlation with each of the delayed replicas of the reference signal. The convolution operation, as shown in the equation above, therefore shows that the received signal appears at different delay points, each delayed replica being weighted by the channel coefficient.

[0206] FIG. 3A and FIG. 3B are plots showing examples of channel responses 360, 370 computed from the wireless signals communicated between wireless communication devices 204A, 204B, 204C in FIG. 2A and FIG. 2B. FIG. 3 A and FIG. 3B also show frequency domain representation 350 of an initial wireless signal transmitted by wireless communication device 204 A. In the examples shown, channel response 360 in FIG. 3A represents the signals received by wireless communication device 204B when there is no motion in space 200, and channel response 370 in FIG. 3B represents the signals received by wireless communication device 204B in FIG. 2B after the object has moved in space 200.

[0207] In the example shown in FIG. 3A and FIG. 3B, for illustration purposes, wireless communication device 204A transmits a signal that has a flat frequency profile (the magnitude of each frequency component,, fa and3is the same), as shown in frequency domainrepresentation 350. Because of the interaction of the signal with space 200 (and the objects therein), the signals received at wireless communication device 204B that are based on the signal sent from wireless communication device 204A are different from the transmitted signal. In this example, where the transmitted signal has a flat frequency profile, the received signal represents the channel response of space 200. As shown in FIG. 3A and FIG. 3B, channel responses 360, 370 are different from frequency domain representation 350 of the transmitted signal. When motion occurs in space 200, a variation in the channel response will also occur. For example, as shown in FIG. 3B, channel response 370 is associated with the motion of an object in space 200 and varies from channel response 360 in FIG. 3A that is associated with no motion in space 200.

[0208] Furthermore, as an object moves within space 200, the channel response may vary from channel response 370. In some cases, space 200 can be divided into distinct 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 distinct regions can be distinguished, and the location of detected motion can be determined based on an analysis of channel responses.

[0209] FIG. 4A and FIG. 4B are diagrams showing example channel responses 401, 403 associated with motion of object 406 in distinct regions 408, 412 of space 400. In the examples shown, space 400 is a building, and space 400 is divided into a plurality of distinct regions -first region 408, second region 410, third region 412, fourth region 414, and fifth region 416. Space 400 may include additional or fewer regions, in some instances. As shown in FIG. 4A and FIG. 4B, the regions within space 400 may be defined by walls between rooms. In addition, the regions may be defined by ceilings between floors of a building. For example, space 400 may include additional floors with additional rooms. In addition, in some instances, the plurality of regions of a space can be or can include a number of floors in a multistory building, a number of rooms in the building, or a number of rooms on a particular floor of the building. In the example shown in FIG. 4A, an object located in first region 408 is represented as person 406, but the moving object can be another type of object, such as an animal or an inorganic object.

[0210] In the example shown, wireless communication device 402A is located in fourth region 414 of space 400, wireless communication device 402B is located in second region 410 of space 400, and wireless communication device 402C is located in fifth region 416 of space 400. Wireless communication devices 402 can operate in the same or similar manner as wireless communication devices 102 of FIG. 1. For instance, wireless communication devices402 may be configured to transmit and receive wireless signals and detect whether motion has occurred in space 400 based on the received signals. As an example, wireless communication devices 402 may periodically or repeatedly transmit motion probe signals through space 400, and receive signals based on the motion probe signals. Wireless communication devices 402 can analyze the received signals to detect whether an object has moved in space 400, such as, for example, by analyzing channel responses associated with space 400 based on the received signals. In addition, in some implementations, wireless communication devices 402 can analyze the received signals to identify a location of detected motion within space 400. For example, wireless communication devices 402 can analyze characteristics of the channel response to determine whether the channel responses share the same or similar characteristics to channel responses known to be associated with first to fifth regions 408, 410, 412, 414, 416 of space 400.

[0211] In the examples shown, one (or more) of wireless communication devices 402 repeatedly transmits a motion probe signal (e.g., a reference signal) through space 400. The motion probe signals may have a flat frequency profile in some instances, wherein the magnitude of, fa and3is the same or nearly the same. For example, the motion probe signals may have a frequency response similar to frequency domain representation 350 shown in FIG. 3A and FIG. 3B. The motion probe signals may have a different frequency profile in some instances. Because of the interaction of the reference signal with space 400 (and the objects therein), the signals received at another wireless communication device 402 that are based on the motion probe signal transmitted from the other wireless communication device 402 are different from the transmitted reference signal.

[0212] Based on the received signals, wireless communication devices 402 can determine a channel response for space 400. When motion occurs in distinct regions within the space, distinct characteristics may be seen in the channel responses. For example, while the channel responses may differ slightly for motion within the same region of space 400, the channel responses associated with motion in distinct regions may generally share the same shape or other characteristics. For instance, channel response 401 of FIG. 4A represents an example channel response associated with the motion of object 406 in first region 408 of space 400, while channel response 403 of FIG. 4B represents an example channel response associated with the motion of object 406 in third region 412 of space 400. Channel responses 401 and 403 are associated with signals received by the same wireless communication device 402 in space 400.

[0213] FIG. 4C and FIG. 4D are plots showing channel responses 401, 403 of FIG. 4A and FIG. 4B overlaid on channel response 460 associated with no motion occurring in space 400. In the example shown, wireless communication device 402 transmits a motion probe signal that has a flat frequency profile as shown in frequency domain representation 450. When motion occurs in space 400, a variation in the channel response will occur relative to channel response 460 associated with no motion, and thus, the motion of an object in space 400 can be detected by analyzing variations in the channel responses. In addition, a relative location of the detected motion within space 400 can be identified. For example, the shape of channel responses associated with motion can be compared with reference information (e.g., using a trained artificial intelligence (Al) model) to categorize the motion as having occurred within a distinct region of space 400.

[0214] When there is no motion in space 400 (e.g., when object 406 is not present), wireless communication device 402 may compute channel response 460 associated with no motion. Slight variations may occur in the channel response due to a number of factors; however, multiple channel responses 460 associated with different periods of time may share one or more characteristics. In the example shown, channel response 460 associated with no motion has a decreasing frequency profile (the magnitude of each of, fa and3is less than the previous). The profile of channel response 460 may differ in some instances (e.g., based on different room layouts or placement of wireless communication devices 402).

[0215] When motion occurs in space 400, a variation in the channel response will occur. For instance, in the examples shown in FIG. 4C and FIG. 4D, channel response 401 associated with the motion of object 406 in first region 408 differs from channel response 460 associated with no motion, and channel response 403 associated with the motion of object 406 in third region 412 differs from channel response 460 associated with no motion. Channel response 401 has a concave-parabolic frequency profile (the magnitude of the middle-frequency component, fa, is less than the outer frequency components fa and3), while channel response 403 has a convex-asymptotic frequency profile (the magnitude of the middle-frequency component fa is greater than the outer frequency components, fa and3). The profiles of channel responses 401, 403 may differ in some instances (e.g., based on different room layouts or placement of the wireless communication devices 402).

[0216] Analyzing channel responses may be considered similar to analyzing a digital filter. A channel response may be formed through the reflections of objects in a space as well as reflections created by a moving or static human. When a reflector (e.g., a human) moves, itchanges the channel response. This may translate to a change in equivalent taps of a digital filter, which can be thought of as having poles and zeros (poles amplify the frequency components of a channel response and appear as peaks or high points in the response, while zeros attenuate the frequency components of a channel response and appear as troughs, low points, or nulls in the response). A changing digital filter can be characterized by the locations of its peaks and troughs, and a channel response may be characterized similarly by its peaks and troughs. For example, in some implementations, analyzing nulls and peaks in the frequency components of a channel response (e.g., by marking their location on the frequency axis and their magnitude), motion can be detected.

[0217] In some implementations, a time series aggregation can be used to detect motion. A time series aggregation may be performed by observing the features of a channel response over a moving window and aggregating the windowed result by using statistical measures (e.g., mean, variance, principal components, etc.). During instances of motion, the characteristic digital-filter features would be displaced in location and flip-flop between some values due to the continuous change in the scattering scene. That is, an equivalent digital filter exhibits a range of values for its peaks and nulls (due to the motion). By looking at this range of values, unique profiles (in examples, profiles may also be referred to as signatures) may be identified for distinct regions within a space.

[0218] In some implementations, an artificial intelligence (Al) model may be used to process data. Al models may be of a variety of types, for example, linear regression models, logistic regression models, linear discriminant analysis models, decision tree models, naive Bayes models, '-nearest neighbors models, learning vector quantization models, support vector machines, bagging and random forest models, and deep neural networks. In general, all Al models aim to leam a function that provides the most precise correlation between input values and output values and are trained using historic sets of inputs and outputs that are known to be correlated. In examples, artificial intelligence may also be referred to as machine learning.

[0219] In some implementations, the profiles of the channel responses associated with motion in distinct regions of space 400 can be learned. For example, machine learning may be used to categorize channel response characteristics with the motion of an object within distinct regions of a space. In some cases, a user associated with wireless communication devices 402 (e.g., an owner or other occupier of space 400) can assist with the learning process. For instance, referring to the examples shown in FIG. 4A and FIG. 4B, the user can move in each of first to fifth regions 408, 410, 412, 414, 416 during a learning phase and may indicate (e.g., through a user interface on a mobile computing device) that he / she is moving in one of theparticular regions in space 400. For example, while the user is moving through first region 408 (e.g., as shown in FIG. 4A) the user may indicate on a mobile computing device that he / she is in first region 408 (and may name the region as “bedroom”, “living room”, “kitchen”, or another type of room of a building, as appropriate). Channel responses may be obtained as the user moves through the region, and the channel responses may be “tagged” with the user’s indicated location (region). The user may repeat the same process for the other regions of space 400. The term “tagged” as used herein may refer to marking and identifying channel responses with the user’s indicated location or any other information.

[0220] The tagged channel responses can then be processed (e.g., by machine learning software) to identify unique characteristics of the channel responses associated with motion in the distinct regions. Once identified, the identified unique characteristics may be used to determine the location of detected motion for newly computed channel responses. For example, an Al model may be trained using the tagged channel responses, and once trained, newly computed channel responses can be input to the Al model, and the Al model can output a location of the detected motion. For example, in some cases, mean, range, and absolute values are input to an Al model. In some instances, the magnitude and phase of the complex channel response itself may be input as well. These values allow the Al model to design arbitrary frontend filters to pick out the features that are most relevant to making accurate predictions with respect to motion in distinct regions of space. In some implementations, the Al model is trained by performing a stochastic gradient descent. For instance, channel response variations that are most active during a certain zone may be monitored during the training, and the specific channel variations may be weighted heavily (by training and adapting the weights in the first layer to correlate with those shapes, trends, etc.). The weighted channel variations may be used to create a metric that activates when a user is present in a certain region.

[0221] For extracted features like channel response nulls and peaks, a time-series (of the nulls / peaks) may be created using an aggregation within a moving window, taking a snapshot of a few features in the past and present, and using that aggregated value as input to the network. Thus, the network, while adapting its weights, will be trying to aggregate values in a certain region to cluster them, which can be done by creating logistic classifier-based decision surfaces. The decision surfaces divide different clusters, and subsequent layers can form categories based on a single cluster or a combination of clusters.

[0222] In some implementations, an Al model includes two or more layers of inference. The first layer acts as a logistic classifier which can divide different concentrations of values into separate clusters, while the second layer combines some of these clusters together to createa category for a distinct region. Additionally, subsequent layers can help in extending the distinct regions over more than two categories of clusters. For example, a fully connected Al model may include an input layer corresponding to the number of features tracked, a middle layer corresponding to the number of effective clusters (through iterating between choices), and a final layer corresponding to different regions. Where complete channel response information is input to the Al model, the first layer may act as a shape filter that can correlate certain shapes. Thus, the first layer may lock to a certain shape, the second layer may generate a measure of variation happening in those shapes, and the third and subsequent layers may create a combination of those variations and map them to different regions within the space. The output of different layers may then be combined through a fusing layer.B. WLAN sensing system example methods and apparatus

[0223] Section B describes systems and methods that are useful for a wireless sensing system configured to establish a WLAN sensing network and make sensing measurements.

[0224] FIG. 5 depicts an implementation of some of the architecture of system 500 to perform disambiguation of multi-link device identities for Wireless Local Area Network (WLAN) sensing operation, according to some embodiments.

[0225] System 500 may include a plurality of MLDs. The plurality of MLDs may include AP MLD 502 and non-AP MLDs 504-(1-N). In an embodiment, the plurality of MLDs may be associated with an Extended Service Set (ESS). The ESS may be a collection of STAs that includes more than one AP device and forms a single, logical service set. The ESS may include more than one Basic Service Set (BSS) and may be identified logically by an SSID that describes the overall wireless network. In an embodiment, the ESS may include two or more BSSs. A BSS is a collection of an AP STA and non-AP STAs which are associated together at a PHY / MAC layer to form a wireless network. The BSS may include a single STA acting as an Access Point (AP or AP STA) and one or more STAs (non-AP STA, or simply STA where the access point is AP) connected to and controlled by the AP device. The BSS may be identified in IEEE 802.11 by a BSSID. Furthermore, the AP device may correspond to AP MLD 502. System 500 may include AP MLD 502, non-AP MLDs 504-(1-N), and network 506 enabling communication between the system components for information exchange.

[0226] Furthermore, non-AP MLDs 504-(1-N) may include sensing controllers 508-(l-N). In an embodiment, sensing controllers 508-(l-N) may be controllers that facilitate and coordinate WLAN sensing-related connections and activities.

[0227] In an exemplary implementation, non-AP MLDs 504-(1-N) may include at least first non-AP MLD 504-1 and second non-AP MLD 504-2. System 500 may be an example or instance of wireless communication system 100 and network 506 may be an example or instance of a wireless network or a cellular network, details of which are provided with reference to FIG. 1 and its accompanying description.

[0228] According to an embodiment, non-AP MLDs 504-(1-N) may be configured to receive one or more sensing transmissions (for example, from AP MLD 502) and perform one or more measurements useful for WLAN sensing (for example, channel representation information (CRI) measurements). In an exemplary embodiment, the CRI measurements may include channel state information (CSI) or time domain channel representation information (TD-CRI) useful for Wi-Fi sensing. For example, these measurements may be known as sensing measurements. The sensing measurements may be processed to achieve a sensing goal of system 500. For example, any of AP MLD 502 and non-AP MLDs 504-(1-N) may be any computing device, such as a desktop computer, a laptop, a tablet computer, a mobile device, a personal digital assistant (PDA), or any other computing device. In some embodiments, one or more of non-AP MLDs 504-(1-N) may take the role of sensing transmitter and / or sensing receiver. In an embodiment, sensing application 510-1 may be implemented in each of non-AP MLDs 504-(1-N) for establishing the Wi-Fi sensing network. For ease of explanation and understanding, the descriptions provided above may be with reference to non-AP MLD 504-1, however, the description is equally applicable to any of non-AP MLDs 504-(2-N).

[0229] According to an implementation, non-AP MLD 504-1 may be implemented by a device, such as wireless communication device 102 shown in FIG. 1. In some implementations, non-AP MLD 504-1 may be implemented by a device, such as wireless communication device 204 shown in FIG. 2A and FIG. 2B. Furthermore, non-AP MLD 504-1 may be implemented by a device, such as wireless communication device 402 shown in FIG. 4A and FIG. 4B. In an implementation, non-AP MLD 504-1 may coordinate and control communication among non-AP MLDs 504-(2-N). According to an implementation, non-AP MLD 504-1 may be enabled to control a sensing measurement session comprising one or more sensing measurement exchanges to ensure that required sensing transmissions are made at required times and to ensure an accurate determination of one or more sensing measurements. In some embodiments, non-AP MLD 504-1 may process the sensing measurements to achieve the sensing goal of system 500. In some embodiments, non-AP MLD 504-1 may be configured to achieve the sensing goal of the system by using AP MLD 502. In other embodiments, non-AP MLD 504-1 may be configured to achieve the sensing goal without using AP MLD 502. In someembodiments, non-AP MLD 504-1 may be configured to transmit the sensing measurements to one or more of non-AP MLDs 504-(2-N), and one or more of non-AP MLDs 504-(2-N) may be configured to process the sensing measurements to achieve a sensing result of system 500. In some embodiments, non-AP MLD 504-1 may be configured to establish the Wi-Fi sensing network using AP MLD 502 and non-AP MLDs 504-(2-N).

[0230] In an embodiment, non-AP MLD 504-1 may be a STA. In some embodiments, non-AP MLD 504-1 may be a non-AP STA. In some embodiments, non-AP MLD 504-1 may be configured to receive sensing measurements from one or more of non-AP MLDs 504-(2-N), and non-AP MLD 504-1 may be configured to establish a Wi-Fi sensing network for processing sensing measurements to achieve the sensing goal of system 500.

[0231] Referring again to FIG. 5, in some embodiments, non-AP MLDs 504-(2-N) may be configured to send one or more sensing transmissions to non-AP MLD 504-1 based on which one or more sensing measurements may be performed for WLAN sensing. In an embodiment, one or more of non-AP MLDs 504-(2-N) may be a STA, a non-AP STA, or a combination thereof. In an embodiment, one or more of non-AP MLDs 504-(2-N) may take the role of sensing initiator and / or sensing responder.

[0232] According to an implementation, one or more of non-AP MLDs 504-(2-N) may be implemented by a device, such as wireless communication device 102 shown in FIG. 1. In some implementations, one or more of non-AP MLDs 504-(2-N) may be implemented by a device, such as wireless communication device 204 shown in FIG. 2A and FIG. 2B. Furthermore, one or more of non-AP MLDs 504-(2-N) may be implemented by a device, such as wireless communication device 402 shown in FIG. 4A and FIG. 4B. In some embodiments, any of non-AP MLDs 504-(2-N) may be any computing device, such as a desktop computer, a laptop, a tablet computer, a mobile device, a PDA, or any other computing device. In some implementations, communication between AP MLD 502, non-AP MLD 504-1, and one or more of non-AP MLDs 504-(2-N) may occur via station management entity (SME) and MAC layer management entity (MLME) protocols.

[0233] In some embodiments, AP MLD 502 may be configured to facilitate the process of WLAN sensing, as explained in further paragraphs using FIG. 6 to FIG. 33B. For example, AP MLD 502 may provide information associated with non-AP MLDs 504-(2-N) to non-AP MLD 504-1 to facilitate the process of WLAN sensing. Accordingly, non-AP MLD 504-1 may perform WLAN sensing based on the received information associated with non-AP MLDs 504-(2-N) and analyze sensing measurements to identify one or more features of interest. According to some implementations, AP MLD 502 may or may not include / execute a sensing application.In an embodiment, a remote processing device (also referred to as AP MLD 502) may be a STA. According to an implementation, AP MLD 502 may be implemented by a device, such as wireless communication device 102 shown in FIG. 1. In some implementations, AP MLD 502 may be implemented by a device, such as wireless communication device 204 shown in FIG. 2A and FIG. 2B. Furthermore, AP MLD 502 may be implemented by a device, such as wireless communication device 402 shown in FIG. 4A and FIG. 4B. In some embodiments, AP MLD 502 may be a hardware device that allows wireless devices to connect to a wired network using Wi-Fi. For example, AP MLD 502 may comprise wireless routers, wireless range extenders, WAPs, outdoor access points, and the like. In some embodiments, AP MLD 502 may not support IEEE P802.1 Ibf. In other embodiments, AP MLD 502 may not be capable of acting as a sensing controller that can manage sensing measurement sessions and a sensing application. Accordingly, non-AP MLD 504-1 may take the role of sensing initiator where sensing application 510-1 determines a WLAN sensing session, and the sensing measurements required to fulfill the measurement campaign. In an example, non-AP MLD 504-1 may communicate sensing measurement parameters and / or transmission parameters required to initiate a WLAN sensing session with non-AP MLDs 504-(2-N) to coordinate and control sensing transmissions for performing sensing measurements.

[0234] Referring to FIG. 5 in more detail, AP MLD 502 may include processor 512 and memory 514. For example, processor 512 and memory 514 of AP MLD 502 may be processor 114 and memory 116, respectively, as shown in FIG. 1. In an embodiment, AP MLD 502 may further include transmitting antenna(s) 516 and receiving antenna(s) 518. In some embodiments, an antenna may be used to both transmit and receive signals in a half-duplex format. When the antenna is transmitting, it may be referred to as transmitting antenna 516, and when the antenna is receiving, it may be referred to as receiving antenna 518. It is understood by a person of normal skill in the art that the same antenna may be transmitting antenna 516 in some instances and receiving antenna 518 in other instances. In the case of an antenna array, one or more antenna elements may be used to transmit or receive a signal, for example, in a beamforming environment. In some examples, a group of antenna elements used to transmit a composite signal may be referred to as transmitting antenna 516, and a group of antenna elements used to receive a composite signal may be referred to as receiving antenna 518. In some examples, each antenna is equipped with its own transmission and receive paths, which may be alternatively switched to connect to the antenna depending on whether the antenna is operating as transmitting antenna 516 or receiving antenna 518.

[0235] In some embodiments, AP MLD 502 may also include sensing measurement storage 520. In an implementation, sensing measurement storage 520 may store sensing measurements computed by AP MLD 502 based on received sensing transmissions. Furthermore, sensing measurement storage 520 may store sensing measurements received by AP MLD 502 based on received messages. For example, sensing measurements stored in sensing measurement storage 520 may be periodically or dynamically updated as required. In an implementation, sensing measurement storage 520 may include any type or form of storage, such as a database or a file system, or may be coupled to memory 514.

[0236] In an embodiment, AP MLD 502 may also include Link Group ID storage 522. For example, Link Group ID storage 522 may store information associated with a unique identifier of a group of links (e.g., sensing links) associated with the plurality of MLDs (e.g., AP MLD 502, and non-AP MLDs 504-(1-N)). Details on information stored in Link Group ID storage 522 have been explained in further paragraphs and in the description of FIG. 31.

[0237] In an embodiment, AP MLD 502 may also include sensing capability storage 524. For example, sensing capability storage 524 may store information associated with a Link Group ID and sensing capabilities of the plurality of MLDs (e.g., AP MLD 502 and non-AP MLDs 504-(1-N)), respectively.

[0238] In an embodiment, AP MLD 502 may include a sensing agent and / or a sensing application (not shown). In an implementation, the sensing agent may be responsible for determining sensing measurement parameters and / or transmission parameters for one or more sensing measurement setups. For example, the sensing agent may receive sensing measurement parameters and / or transmission parameters for one or more sensing measurement setups from the sensing application. In an example, the sensing agent may receive sensing measurements from one or more of the plurality of non-AP MLDs and may process the sensing measurements to fulfill a sensing goal. In an example, the sensing agent may receive channel representation information (such as CSI or TD-CRI) from non-AP MLDs 504-(1-N) to process the channel representation information for fulfilling a sensing goal. In some implementations, the sensing agent may receive sensing measurements or channel representation information and may provide the received sensing measurements or channel representation information to the sensing application. Furthermore, the sensing application may receive the sensing measurements or channel representation information from the sensing agent and may process the information to fulfill a sensing goal. In other implementations, AP MLD 502 may fail to perform the functionalities or tasks associated with the sensing agent due to one or more errors.

[0239] Referring to FIG. 5 in more detail, non-AP MLD 504-1 may include processor 526-1 and memory 528-1. For example, processor 526-1 and memory 528-1 of non-AP MLD 504-1 may be processor 114 and memory 116, respectively, as shown in FIG. 1. In an embodiment, non-AP MLD 504-1 may further include transmitting antenna(s) 530-1, receiving antenna(s) 532-1, and sensing agent 534-1. In an embodiment, sensing agent 534-1 may be a module that allows non-AP MLD 504-1 to participate in WLAN sensing. Non-AP MLD 504-1, which implements sensing agent 534-1, may implement techniques and technology defined by IEEE P802.1 Ibf which is a standard that describes enhancements to a WLAN MAC and PHY layer for WLAN sensing. In some embodiments, an antenna may be used to both transmit and receive signals in a half-duplex format. When the antenna is transmitting, it may be referred to as transmitting antenna 530-1. Furthermore, when the antenna is receiving, it may be referred to as receiving antenna 532-1. It is understood by a person of normal skill in the art that the same antenna may be transmitting antenna 530-1 in some instances and receiving antenna 532-1 in other instances. In the case of an antenna array, one or more antenna elements may be used to transmit or receive a signal, for example, in a beamforming environment. In some examples, a group of antenna elements used to transmit a composite signal may be referred to as transmitting antenna 530-1, and a group of antenna elements used to receive a composite signal may be referred to as receiving antenna 532-1. In some examples, each antenna is equipped with its transmit and receive paths, which may be switched to connect to the antenna depending on whether the antenna is operating as transmitting antenna 530-1 or receiving antenna 532-1.

[0240] In an implementation, sensing agent 534-1 may be responsible for causing non-AP MLD 504-1 to receive sensing transmissions and associated sensing measurement parameters and / or transmission parameters and to calculate sensing measurements. For example, sensing agent 534-1 may be responsible for processing sensing measurements to fulfill a sensing goal. In some implementations, receiving sensing transmissions and optionally associated sensing measurement parameters and / or transmission parameters, and calculating sensing measurements may be carried out by sensing agent 534-1 running in the medium access control (MAC) layer of non-AP MLD 504-1 and processing sensing measurements to fulfill a sensing goal may be carried out by an algorithm running in the application layer of non-AP MLD 504-1, for example sensing application 510-1. For example, sensing application 510-1 running in the application layer of non-AP MLD 504-1 may be known as a WLAN sensing agent, a sensing application, or a sensing algorithm. For example, sensing application 510-1 may include and / or execute sensing agent 534-1. According to some implementations, sensing agent 534-1 may include and / or execute sensing application 510-1. In some implementations, sensingagent 534-1 running in the MAC layer of non-AP MLD 504-1 and sensing application 510-1 running in the application layer of non-AP MLD 504-1 may run separately on processor 526-1. In an implementation, sensing agent 534-1 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, CIR, and TD-CRI) between the MAC layer of non-AP MLD 504-1 and the application layer of non-AP MLD 504-1. For example, sensing agent 534-1 in the MAC layer or sensing application 510-1 in the application layer may operate on physical layer parameters, for example, to detect one or more features of interest. For example, sensing application 510-1 may form services or features, which may be presented to an end-user. According to an implementation, communication between the MAC layer of non-AP MLD 504-1 and other layers or components of non-AP MLD 504-1 (including the application layer) may take place based on communication interfaces, such as an MLME interface and a data interface. For example, sensing agent 534-1 may be configured to determine at least one of a number, a timing, an amplitude, and a phase of sensing transmissions and sensing measurements for the purpose of WLAN sensing. In some implementations, sensing agent 534-1 may be configured to transmit sensing measurements to non-AP MLDs 504-(2-N) and / or remote processing devices (or AP MLD 502) for further processing. In an implementation, sensing agent 534-1 may be configured to cause at least one transmitting antenna of transmitting antenna(s) 530-1 to transmit messages to one or more of non-AP MLDs 504-(2-N) and / or to AP MLD 502. Furthermore, sensing agent 534-1 may be configured to receive, via at least one receiving antenna of receiving antenna(s) 532-1, messages from one or more of non-AP MLDs 504-(2-N) or AP MLD 502. In an example, sensing agent 534-1 may be configured to make sensing measurements based on sensing transmissions received from one or more of non-AP MLDs 504-(2-N) and / or AP MLD 502.

[0241] In some embodiments, non-AP MLD 504-1 may include sensing measurement storage 536-1. In an implementation, sensing measurement storage 536-1 may store sensing measurements computed by non-AP MLD 504-1 based on received sensing transmissions. Furthermore, sensing measurement storage 536-1 may store sensing measurements received by non-AP MLD 504-1 based on received messages. For example, sensing measurements stored in sensing measurement storage 536-1 may be periodically or dynamically updated as required. In an implementation, sensing measurement storage 536-1 may include any type or form of storage, such as a database or a file system, or may be coupled to memory 528-1.

[0242] In an embodiment, non-AP MLD 504-1 may also include Link Group ID storage 538-1. For example, Link Group ID storage 538-1 may store information associated with aunique identifier of a group of links (e.g., sensing links) associated with the plurality of MLDs (e.g., AP MLD 502, non-AP MLDs 504-(1-N)). Details on information stored in Link Group ID storage 538-1 have been explained in further paragraphs and in the description of FIG. 31.

[0243] In an embodiment, non-AP MLD 504-1 may also include sensing capability storage 540-1. For example, sensing capability storage 540-1 may store information associated with the Link Group ID and sensing capabilities of the plurality of MLDs (e.g., AP MLD 502 and non-AP MLDs 504-(1-N)), respectively.

[0244] In an embodiment, non-AP MLD 504-1 acting as a sensing transmitter may perform a sensing transmission which is received by non-AP MLDs 504-(2-N) acting as sensing receivers. Furthermore, non-AP MLD 504-1 may act as a sensing transmitter for a sensing measurement instance. Furthermore, non-AP MLD 504-1 may act as a sensing receiver for the same sensing measurement instance.

[0245] In an embodiment, non-AP MLD 504-1 is shown in FIG. 5. However, there may be multiple non-AP MLDs 504-(2-N) acting as a sensing transmitter for a sensing measurement instance and / or a sensing receiver for the same sensing measurement instance. Furthermore, each of the plurality of MLDs may use the systems and methods of the present disclosure to form the sensing network.

[0246] For ease of explanation and understanding, the descriptions provided above may be with reference to non-AP MLD 504-1; however, the description is equally applicable to one or more of non-AP MLDs 504-(2-N).

[0247] According to one or more implementations, communications in network 506 may be governed by one or more of the 802.11 family of standards developed by IEEE. Some example IEEE standards may include IEEE 802.11, IEEE 802.11 ax, IEEE 802. lime, IEEE 802.11az and IEEE 802.11be. IEEE 802.11 and IEEE 802.11ax are fully ratified standards whilst IEEE 802. lime reflects an ongoing maintenance update to the IEEE 802.11 standard and IEEE 802.11 be defines the next generation of standard. IEEE 802.11 az is an extension of the IEEE 802.11 and IEEE 802.1 lax standards which adds new functionality. In some implementations, communications may be governed by other standards (other or additional IEEE standards or other types of standards). In some embodiments, parts of network 506 that are not required by system 500 to be governed by one or more of the 802.11 family of standards may be implemented by an instance of any type of network, including wireless networks or cellular networks. Furthermore, IEEE 802.1 lax includes Orthogonal Frequency Division Multiple Access (OFDMA), which allows non-AP MLD 504-1 to simultaneously transmit data to all participating devices, such as non-AP MLDs 504-(2-N), and vice versa using a singletransmission opportunity (TXOP). The efficiency of OFDMA depends on how non-AP MLD 504-1 schedules channel resources (interchangeably referred to as Resource Units (RUs)) among non-AP MLDs 504-(2-N) and configures transmission parameters. According to an implementation, system 500 may be an OFDMA-enabled system.

[0248] In a Wi-Fi system, both data transmissions and sensing transmissions may happen at different TXOPs. The Wi-Fi sensing system may utilize a TXOP that is not used for data transmissions, for Wi-Fi sensing. A TXOP used for data transmissions may be named as a data TXOP, while a TXOP used for sensing transmissions may be named as a sensing TXOP.

[0249] Referring back to FIG. 5, according to one or more implementations, WLAN sensing system 500 may participate in a sensing session. For example, a sensing session is an agreement between a sensing initiator and a sensing responder to participate in a WLAN sensing procedure (also known as a Wi-Fi sensing procedure). For example, sensing measurement parameters associated with a sensing session may be determined by a sensing initiator and may be exchanged between the sensing initiator and a sensing responder. For example, a sensing initiator may be non-AP MLD 504-1 and sensing responder(s) may be one (or more) of non-AP MLDs 504-(2-N). For example, a sensing initiator may be non-AP MLD 504-1, and a sensing responder may be non-AP MLD 504-2. For example, a sensing initiator may be non-AP MLD 504-2, and a sensing responder may be non-AP MLD 504-1. For example, a networking device (e.g., any of non-AP MLDs 504-(1-N) and AP MLD 502) may participate in multiple sensing sessions either as a sensing initiator or as a sensing responder. For example, non-AP MLD 504-1 may participate in multiple sensing sessions either as a sensing initiator or as a sensing responder. For example, AP MLD 502 may or may not participate in multiple sensing sessions as a sensing initiator or as a sensing responder.

[0250] FIG. 6 is reproduced from IEEE P802.1 Ibf and illustrates an example of a WLAN sensing procedure 600 (also known as a Wi-Fi sensing procedure 600) according to some embodiments. For example, a WLAN sensing procedure allows an STA to perform WLAN sensing. For example, a WLAN sensing procedure enables a STA to obtain one or more sensing measurements of the wireless transmission channel between two or more STAs and / or the wireless transmission channel between a transmitting antenna and a receiving antenna of a STA. For example, a WLAN sensing procedure is composed of one or more of a sensing session setup, a sensing measurement setup, one or more sensing measurement exchanges, a sensing measurement setup termination, and a sensing session termination.

[0251] FIG. 6 illustrates an example of a WLAN sensing procedure 600 with a sensing measurement session set up with a STA with MAC ADDR=A and Association Identifier(AID)=1, and is a reproduction of FIG. AD-1 of IEEE P802.1 Ibf D3.0. For example, a sensing measurement session setup establishes a sensing session or a sensing procedure. For example, the sensing measurement session may be identified by the AID of the STA involved in the sensing measurement session. FIG. 6 illustrates a measurement session setup procedure for the STA with MAC ADDR=A, where the measurement session ID = 1.

[0252] For example, a sensing measurement session setup allows for a sensing initiator and a sensing responder to exchange and agree on operational attributes associated with a sensing measurement exchange. A sensing initiator may transmit a Sensing Measurement Setup Request frame to a sensing responder with which it intends to perform a sensing measurement session setup. An example of a Sensing Measurement Request frame Action field format 702 (which may also be referred to as a Sensing Measurement Setup Request frame Action field format) as described by IEEE P802.1 Ibf D3.0 in FIG. 9-1198a is provided in FIG.7A. As shown in the example illustrated in FIG. 7A, in embodiments, a Sensing Measurement Setup Request frame Action field format may include one or more of a Category field, a Public Action field, a Dialog Token field, a Sensing Comeback Info field, a Measurement Session ID Indication field, and a Sensing Measurement Parameters element. In examples, a Category value code is defined for a “Protected Sensing Frame”. In an embodiment, a Protected Sensing Action field is defined in the octet immediately after the Category field in order to differentiate Protected Sensing Frame formats from Public Sensing Frame formats.

[0253] FIG. 7B is reproduced from IEEE P802.11bf D3.0, FIG. 9-1001bc and illustrates an example, according to some embodiments, of a Sensing Measurement Parameters element format 704. For example, a Sensing Measurement Parameters element indicates operational attributes of a corresponding sensing measurement exchange. For example, the Sensing Measurement Parameters element comprises a Sensing Measurement Parameters field and a Sensing sub-elements field. FIG. 7C is reproduced from IEEE P802.11bf D3.0, FIG. 9-1001bd and illustrates an example of a format of the Sensing Measurement Parameters field format, according to some embodiments. In an example, a Sensing Measurement Parameters field comprises a Sensing Transmitter subfield. The Sensing Transmitter subfield may be set to 1 to indicate a sensing responder assumes a sensing transmitter role, such as non-AP MLD 504-1. In an example, the sensing responder assumes a sensing transmitter role according to the Sensing Transmitter subfield for the Sensing Measurement Session ID Indication associated with the Sensing Measurement Parameters field. For example, the Sensing Measurement Parameters field comprises a Sensing Receiver subfield. The Sensing Receiver subfield may be set to 1 to indicate a sensing responder assumes a sensing receiver role, such as non-APMLD 504. In an example, the sensing responder assumes a sensing receiver role according to the Sensing Receiver subfield for the Sensing Measurement Session ID Indication associated with the Sensing Measurement Parameters field.

[0254] Referring again to FIG. 7C, in examples, a Sensing Measurement Parameters field format 706 includes a Sensing Measurement Report Requested subfield if the Sensing Receiver subfield indicates that the sensing responder should assume a sensing receiver role. For example, the Sensing Measurement Report Requested subfield may indicate whether or not a sensing responder sends Sensing Measurement Report frames in sensing measurement exchanges that result from the sensing measurement session setup.

[0255] For example, after the sensing responder receives the Sensing Measurement Setup Request frame, the sensing responder may transmit a Sensing Measurement Setup Response frame. An example of a Sensing Measurement Response frame Action field format 708 (which may also be referred to as a Sensing Measurement Setup Response frame Action field format) is described by IEEE P802.1 Ibf D3.0, FIG. 9-1198d and is provided in FIG. 7D. For example, the sensing responder may use a Status Code field in the Sensing Measurement Setup Response frame to indicate whether the sensing responder accepts the requested sensing measurement setup parameters in the received Sensing Measurement Setup Request frame. In an embodiment, the Status Code field may be set to 0 indicating a successful sensing measurement setup, where the sensing responder accepts the operational attributes included in the Sensing Measurement Setup Request frame. In examples, the sensing responder may indicate in the Sensing Measurement Setup Response frame that the operational attributes included 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. For example, the sensing responder may indicate in the Sensing Measurement Setup Response frame suggested sensing measurement parameters, for example, to indicate to the sensing initiator one or more operational attributes preferred by the sensing responder. For example, the sensing responder may indicate to the sensing initiator that suggested sensing measurement parameters are included in the Sensing Measurement Setup Response frame by setting the Status Code field to a non-zero value.

[0256] For 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 a sensing responder that the sensing responder is to assume the role of a sensing receiver, or the role of a sensing transmitter, or the role of sensing receiver and sensing transmitter. In examples, the sensing initiator may indicate to thesensing responder whether the sensing responder sends Sensing Measurement Report frames in sensing measurement exchanges. In an embodiment, the role assigned to the sensing responder and / or whether the sensing responder sends Sensing Measurement Report frames persist until the sensing measurement setup is terminated.

[0257] Referring again to FIG. 6 and the measurement session with the STA with MAC ADDR=A and AID=1, the measurement session setup is followed by one or more sensing measurement exchanges and measurement reporting instances which may be performed based on the defined operational attribute set. In the example shown in FIG. 6, the one or more sensing measurement exchanges and measurement reporting instances for the STA with MAC ADDR=A may be assigned measurement exchange IDs; for example, a first measurement exchange may be assigned measurement exchange ID=1, and a second measurement exchange may be assigned measurement exchange ID=2. For example, a measurement exchange may be uniquely associated with a measurement session setup.

[0258] Referring again to FIG. 6, a second measurement session setup may be initiated for the STA with MAC ADDR=A, which may be identified as measurement session ID=2. Measurement session ID=2 may be associated with a second operational attribute set. For example, after the second sensing measurement session setup, any subsequent one or more sensing measurement exchanges may be performed based on either the first operational attribute set (measurement session ID=1) or the second operational attribute set (measurement session ID=2).

[0259] Referring again to FIG. 6, a measurement session setup with a STA with MAC ADDR=B and Unassociated STA Identifier (USID)=2 is illustrated. For example, the measurement session may be identified by the USID of the STA with MAC ADDR=B. FIG. 6 further illustrates a sensing measurement exchange for the STA with MAC ADDR=B. In the example, the operational attribute set for the measurement session for the STA with MAC ADDR=B is the same as the second operational attribute set established with the STA with MAC ADDR=A, and the same measurement session ID is used for both the STA with MAC ADDR=A and the STA with MAC ADDR=B. That is, a sensing measurement session ID (which may also be referred to as a sensing measurement session label) may apply to one or more STAs. In examples according to FIG. 6, subsequent sensing measurement exchanges associated with measurement session ID=2 may be associated with the STA with MAC ADDR=A, the STA with MAC ADDR=B, or with both the STA with MAC ADDR=A and the STA with MAC ADDR=B. Each sensing measurement exchange may have one-to-many(including one-to-one) announcements and / or triggering and may have either one-to-many or many-to-one (including one-to-one) sounding.

[0260] In examples, an operational attribute set of a measurement session may be terminated by performing a sensing measurement session termination procedure, for example as is shown in FIG. 6 for sensing measurement session ID=1 and the STA with MAC ADDR=A. In examples, the sensing measurement session ID of a terminated sensing measurement setup may be used for a subsequent sensing measurement session. This is shown in FIG. 6 where a sensing measurement session with ID=1 is established for the STA with MAC ADDR=B, after the termination of the sensing measurement session ID=1 with the STA with MAC ADDR=A. In some embodiments, a sensing measurement session may be terminated using a sensing measurement session termination procedure, as shown in FIG. 6.

[0261] FIG. 8A illustrates that measurement exchanges 802 between a sensing initiator and a sensing responder may be one-to-many or many-to-one. In examples, a measurement exchange and / or measurement reporting may have a one-to-one (single device to single device) announcement or triggering or may have a one-to-many (single device to multiple devices) announcement or triggering. In examples, a measurement exchange may have one-to-one, one-to-many, or many-to-one (many devices to a single device) sounding.

[0262] As previously described, a sensing measurement session is an agreement between a sensing initiator and a sensing responder to participate in a WLAN (Wi-Fi) sensing procedure. In examples, a sensing session is pairwise and in examples, may be identified by a sensing measurement ID, MAC addresses of the sensing initiator and the sensing responder or AID / USID values, or by any combination of these or other identifiers. FIG. 8B shows an example of a sensing procedure which includes pairwise exchanges or procedures 804 that may take place between a sensing initiator and a sensing responder. The sensing procedure may be related to a sensing measurement session. The example may include one or more of a sensing capabilities exchange, a sensing measurement session (a sensing measurement session setup), one or more sensing measurement exchanges, and a sensing measurement termination (a sensing measurement session termination).

[0263] In examples, a sensing measurement exchange of a WLAN sensing procedure may be a trigger-based (TB) sensing measurement exchange. FIG. 9A and FIG. 9B depict a message flow 900 of a sensing measurement session of a WLAN sensing procedure comprising a sensing measurement session setup procedure followed by one or more trigger-based (TB) sensing measurement exchanges that consist of either NDPA sounding or trigger frame (TF) sounding, followed by a sensing measurement session termination procedure, according tosome examples. In examples, a TB sensing measurement exchange may be used where the sensing initiator is an AP, and one or more non-AP STAs are sensing responders. In examples, a TB sensing measurement exchange may include a polling phase, an NDPA sounding phase, a trigger frame (TF) sounding phase, and a reporting phase.

[0264] FIG. 10A is reproduced from IEEE P802.11bf D3.0, FIG. 11 -102b and illustrates an example of a TB sensing measurement exchange 1002 including a polling phase, an NDPA sounding phase, a TF sounding phase, and a reporting phase. In some examples, TB sensing measurement exchange 1002 may be preceded by an initial Control frame (ICF). The ICF may be sent by a sensing initiator prior to the polling phase. In an example, the sensing initiator may be an AP affiliated with an AP MLD. In an example, the ICF may provide control information to a sensing responder. The control information may relate to Multi-Link Operation (MLO), to the sensing initiator, and / or to the sensing responder.

[0265] The table in FIG. 10B indicates valid combinations of phases 1004 of a TB sensing measurement exchange, in some examples.

[0266] FIG. 11 is reproduced from IEEE P802.11bf D3.0, FIG. 11-102c and provides one example of a TB sensing measurement exchange 1100 with non-AP MLD 504-1, non-AP MLDs 504-(2-N)), or any combination thereof in the role of a sensing initiator and six STAs, referred to as STA 1, STA 2, STA 3, STA 4, STA 5 and STA 6 (such as non-AP MLDs 504-(1-N) as discussed with reference to FIG. 5), all of which in the example are sensing responders. In an example, the client device (for example, any one of STA 4, STA 5, and STA 6) communicates with the sensing initiator to achieve a sensing goal. In the example, the TB sensing measurement exchange comprises a polling phase, an NDPA sounding phase, a TF sounding phase, and a reporting phase. In the example, STA 1, STA 2, and STA 3 act as sensing transmitters, such as non-AP MLD 504-1, non-AP MLD 504-2, and non-AP MLD 504-3, respectively. In the example of FIG. 11, STA 4, STA 5, and STA 6 act as sensing receivers, such as non-AP MLD 504-4, non-AP MLD 504-5, and non-AP MLD 504-6, respectively. In examples, in the polling phase, the AP (such as AP MLD 502) acting as the sensing initiator transmits a Sensing Polling Trigger frame to STA 1, STA 2, STA 3, STA 4, STA 5, and STA 6. In an embodiment, sensing transmitter STA 1 and sensing transmitter STA 2 respond to the Sensing Polling Trigger frame with an indication that the STA is available to participate in a sensing measurement exchange. In examples, the indication is a CTS-to-self (Clear to Send) frame. In the example, sensing transmitter STA 3 does not respond to the Sensing Polling Trigger frame sent by the sensing initiator, indicating that STA 3 will not participate in the sensing measurement exchange. In an embodiment, sensing receiver STA 4 and sensingreceiver STA 5 each respond to the Sensing Polling Trigger frame with an indication that the STA is available to participate in a sensing measurement exchange. In examples, the indication is a CTS-to-self frame. In the example, sensing receiver STA 6 does not respond to the Sensing Polling Trigger frame sent by the AP as the sensing initiator, indicating that STA 6 will not participate in the sensing measurement exchange.

[0267] Referring again to FIG. 11, in a NDPA sounding phase, the AP acting as sensing initiator assumes the role of sensing transmitter. In examples, the AP as a sensing transmitter transmits a sensing transmission. In examples, the sensing transmission may be a broadcast transmission. In examples, the sensing transmission may be a unicast transmission to one or more STAs, for example to sensing receiver STA 4, sensing receiver STA 5 and / or to sensing receiver STA 6. In examples, a period of one or more SIFSs elapses between the AP as sensing transmitter sending the sensing NDPA frame and when the AP as sensing transmitter sends the one or more sensing transmissions. In examples, one or more of the sensing transmissions may be a full bandwidth NDP frame. In examples, one or more of the sensing transmissions may be a partial bandwidth NDP frame. In examples, one or more of the NDP frames may be a SI2SR NDP frame.

[0268] The sensing measurement exchange of FIG. 11 includes a TF Sounding phase. For example, in the TF Sounding phase, the AP as the sensing initiator sends a Sensing Sounding Trigger frame to sensing transmitter STA 1 and to sensing transmitter STA 2. For example, responsive to receiving the Sensing SR2SI Sounding Trigger frame, sensing transmitter STA 1 and sensing transmitter STA 2 send sensing transmissions to the AP. For example, the sensing transmissions may comprise NDP transmissions. In an example, one or more of the NDP transmissions to the AP may be SR2SI NDP transmissions (as shown in the example of FIG.11). In examples, a period of one or more SIFSs elapses between sensing transmitter STA 1 receiving the Sensing SR2SI Sounding Trigger frame and transmitting a sensing transmission, and in examples a period of one or more SIFSs elapses between sensing transmitter STA 2 receiving the Sensing SR2SI Sounding Trigger frame and transmitting a sensing transmission. For example, the AP may assume the role of sensing receiver, and the AP may make sensing measurements on the sensing transmissions from sensing transmitter STA 1 and sensing transmitter STA 2.

[0269] For example, a sensing measurement exchange of a WLAN sensing procedure may be a non-trigger-based (non-TB) sensing measurement exchange. FIG. 12A and FIG. 12B depict a message flow 1200 of a sensing measurement session setup procedure followed by one or more non-TB sensing measurement exchanges of a WLAN sensing procedure thatconsist of one or more of downlink sounding or uplink sounding, according to some embodiments, followed by a sensing measurement session termination procedure, according to some examples. For example, a non-TB sensing measurement exchange may be used where the sensing initiator is a non-AP STA, and an AP is the sensing responder. Examples of uplink sounding are described by IEEE P802.11bf, an example of which is shown in FIG. 12A and FIG. 12B. The sensing initiator (non-AP STA) acting as a sensing transmitter (for example, non-AP MLD 504-1) transmits a sensing announcement frame followed by a sensing transmission. For example, the sensing announcement frame may be an NDPA frame. For example, the sensing transmission may be an NDP frame (for example, a SI2SR NDP frame). For example, responsive to receiving the sensing transmission, the AP acting as a sensing receiver (for example, AP MLD 502), may transmit to the sensing initiator (non-AP STA in the role of non-AP MLD 504-1) a sensing measurement report, for example, one or more Sensing Measurement Report frames. An example of downlink sounding is shown in FIG. 12A and FIG. 12B, the sensing initiator (non-AP STA) acting as a sensing receiver transmits a sensing announcement frame. For example, the sensing announcement frame may be an NDPA frame. For example, responsive to receiving the sensing announcement frame, the AP acting as a sensing transmitter may transmit one or more sensing transmissions. For example, one or more of the sensing transmissions may be an NDP frame (for example, an SI2SR NDP frame). For example, the non-AP STA acting as a sensing receiver, responsive to receiving a sensing transmission, may make a sensing measurement on the sensing transmission. For example, the sensing measurement session may be terminated by the sensing initiator or the sensing responder transmitting a SENS Measurement Setup Termination frame. For example, the sensing responder or sensing initiator (respectively) may respond with an acknowledgment.

[0270] FIG. 13 is reproduced from IEEE P802.11bf D3.0, FIG. 1 l-102i and illustrates a detailed example of a non-TB sensing measurement exchange 1300, according to some embodiments. For example, STA 1 (such as non-AP MLD 504-1) acting as sensing initiator and sensing transmitter, transmits a sensing announcement frame. For example, the sensing announcement frame may be a sensing NDPA frame. For example, one or more SIFSs may elapse followed by STA 1, acting as sensing initiator and sensing transmitter transmitting one or more sensing transmissions. For example, one or more of the sensing transmissions may be an NDP frame (for example, a SI2SR NDP frame). For example, STA 1, acting as sensing initiator and sensing receiver, may transmit a sensing announcement frame followed after a period of time by a SI2SR NDP frame. For example, the sensing announcement frame may be a sensing NDPA frame and the period may be a SIFS. For example, one or more SIFSs mayelapse followed by the AP, acting as sensing responder and sensing transmitter, transmitting one or more sensing transmissions. For example, the AP, acting as a sensing responder and sensing transmitter, does not transmit an NDPA frame and instead transmits a sensing transmission one SIFS after receiving the SI2SR NDP. For example, the sensing transmission may be an NDP frame (for example, an SR2SI NDP frame).

[0271] FIG. 14A is reproduced from IEEE P802.11bf D3.0, FIG. 9-1198f and illustrates an example of a Sensing Measurement Report frame Action field format 1402. In some examples, a Sensing Measurement Report frame may be transmitted to provide WLAN sensing measurements, for example to a sensing agent or a sensing application (or a sensing algorithm) of a sensing initiator. For example, a Sensing Measurement Report frame may comprise one or more Sensing Measurement Report Containers. FIG. 14B is reproduced from IEEE P802.11bf D3.0, FIG. 9-1189g and is an example of a Sensing Measurement Report Container field format 1404. A Sensing Measurement Report Container may comprise a single sensing measurement report, in some embodiments.

[0272] Referring again to FIG. 14B, in embodiments a Sensing Measurement Report Container may include a Sensing Measurement Report Control field 1406. For example, the Sensing Measurement Report Control field 1406 may contain information necessary to interpret the Sensing Measurement Report field. For example, the Sensing Measurement Report Control field 1406 format may comprise one or more subfields. In an embodiment, one or more subfields of the Sensing Measurement Report Control field may include PHY layer parameters used by the sensing receiver when performing the sensing measurement, for example, receiver antenna beamforming or spatial layer information. For example, Sensing Measurement Report Control field 1406 definitions are shown in Table 9-127h from IEEE P802.11bf D3.0, which is reproduced below.Table 9-127h — Sensing Measurement Report Control field definition

[0273] In a sensing session, exchanges of transmissions between a sensing receiver (e.g., non-AP MLD 504-1 or non-AP MLDs 504-(2-N)) and one or more of a plurality of sensing transmitters (e.g., non-AP MLDs 504-(2-N) or non-AP MLD 504-1) may occur. For example, control of these transmissions may be with the MAC layer of the IEEE 802.11 stack. According to an implementation, a sensing receiver may secure a TXOP which may be allocated to one or more sensing transmissions by one or more of the plurality of sensing transmitters. According to an implementation, a sensing receiver may allocate channel resources (or RUs) within a TXOP to one or more of the plurality of sensing transmitters. For example, a sensing receiver may allocate the channel resources to one or more of the plurality of sensing transmitters by allocating time and bandwidth within the TXOP to the one or more of the plurality of sensing transmitters.

[0274] According to an implementation, example 1500 of a hierarchy of fields within a sensing trigger message is shown in FIG. 15A to FIG. 151.

[0275] As described in FIG. 15A and based upon a Trigger frame as described by IEEE P802.11, the Common Info field may contain information that is common to one or more of a plurality of sensing transmitters (e.g., non-AP MLDs 504-(1-N), as shown in FIG. 5). According to some implementations, the requirement of an NDPA preceding an NDP may beoptional. This may be indicated to one or more of the plurality of sensing transmitters and may, for example, be encoded into a “Trigger Dependent Common Info” field if the requirement is common to the plurality of sensing transmitters, or into a “Trigger Dependent User Info” field if the requirement is specific to one or more sensing transmitters of the plurality of sensing transmitters. According to an example, the requirement for a sensing announcement (for example, an NDPA) preceding a sensing response NDP may be encoded by a single bit where 0 (bit clear) indicates that a sensing announcement is optional and 1 (bit set) indicates that a sensing announcement is required.

[0276] As described by FIG. 15B which is a reproduction of IEEE P802.11bf D3.0 FIG.9-102a (Trigger Dependent Common Info field format of the Sensing Polling, SR2SI Sounding, Sensing Reporting, and Sensing Threshold-based Reporting Trigger frame), a Trigger Dependent Common Info field format may include the Sensing Trigger Subtype field with different values to indicate different Sensing Trigger frame variants. The Sensing Trigger frame variants may be used for Sensing Polling, SR2SI Sounding, Sensing Threshold-based Report, Sensing Reporting, or Sensing Responder to Sensing Responder (SR2SR) Sounding.

[0277] As adapted from IEEE P802.11 and IEEE P802.11bf and described in FIG. 15C, a Trigger Type (within B0.. B3 of the “Common Info” field) may be defined as a sensing trigger message. For example, a sensing trigger message may have a Trigger Type subfield value of 8.

[0278] As described by IEEE P802.11 and reproduced in FIG. 15D the sensing trigger message may have an uplink bandwidth (UL BW) subfield value of 0, 1, 2, or 3 corresponding to bandwidths of 20 MHz, 40 MHz, 80 MHz, or 80+80 MHz (160 MHz), respectively.

[0279] As described in FIG. 15E and based upon a Trigger frame as described by IEEE P802.11, the User Info field contains information that is specific to each of the plurality of sensing transmitters. For example, the User Info field may include the AID of a sensing transmitter, an RU allocation for a sensing transmitter, and other Trigger Dependent User Info.

[0280] As described in FIG. 15F and leveraging the definition of IEEE P802.11, the AID12 subfield of the User Info field illustrated in FIG. 15D may be used to address a specific sensing transmitter of the plurality of sensing transmitters.

[0281] As described in FIG. 15G and FIG. 15H and leveraging the definition of IEEE P802.11, the RU Allocation subfield is used to allocate resource units (RUs) to each of the plurality of sensing transmitters 504-(1-N).

[0282] As described in FIG. 151, the Trigger Dependent User Info subfield may be used to request the transmission configuration and / or steering matrix configuration for one or moresensing transmitters of the plurality of sensing transmitters that the sensing trigger message is triggering.C. Systems and methods to form a wireless sensing network

[0283] The present disclosure generally relates to systems and methods to form a wireless sensing network. In particular, the present disclosure relates to systems and methods that are useful to perform the disambiguation of multi-link device (MLD) identities for WLAN sensing operation.

[0284] Wi-Fi 7 introduces Multi-Link Operation (MLO) and anew PHY layer (Extremely High Throughput (EHT)) with new capabilities. However, sensing is not defined for Wi-Fi 7 or MLO. Sensing as defined in P802.11bf may be link-to-link. There may be a benefit in supporting the establishment of multi-link sensing measurement sessions between an MLD sensing initiator (e.g., an AP MLD) and an MLD sensing responder (e.g., a non-AP MLD). Furthermore, there may be a requirement to support link-specific sensing measurement sessions on specific links between the MLD sensing initiator and the MLD sensing responder. An MLD may have capabilities that may correspond to sensing on all links of the MLD (e.g., WLAN sensing is supported on 5 GHz and 6 GHz but not 2.4 GHz); however, sensing capabilities that may correspond to the APs affiliated with the AP MLD (e.g., bandwidth, supported long training fields, etc.) and non-AP STAs affiliated with the non-AP MLD may also be necessary, e.g., some sensing capabilities may be specific to a link and not applicable at the MLD level.

[0285] Furthermore, to identify features of interest in the sensing space, the sensing initiator (responsible for setting up sensing sessions) is required to specify the Media Link Directions across which a sensing link between an Access Point (AP) and a Station (STA) is established. Sensing measurement sessions are set up per link and sensing measurements are made per link. To be able to successfully process the sensing measurements for determining a sensing result and detecting features of interest, the sensing initiator is required to identify the collection of links between the AP MLD and the non-AP MLD. As a result, it may be ensured that sufficient sensing sessions (e.g., sensing sessions on at least one link between the relevant MLDs) may be established to cover the sensing space.

[0286] Additionally, the sensing parameters of the sensing measurement session setup are required to be established per link. Thus, an unambiguous way to identify the sensing capabilities of the AP and the non-AP STA of each link may be required, when there may be more than one AP in the AP MLD and more than one non-AP STA in the non-AP MLD. Whenthe sensing initiator may be on a separate device, the sensing initiator may be required to know which lower MAC addresses are associated with which MLD, or equivalently, which links are associated with which AP MLD - non-AP MLD pair. As a result, sensing sessions may be set up and sensing measurements may be processed from the sensing sessions.

[0287] A WLAN sensing system may be configured to detect features of interest in a sensing space. The WLAN sensing system may be a network of Wi-Fi-enabled devices that are part of an IEEE 802.11 network (sometimes referred to as a Basic Service Set (BSS) or Extended Service Set (ESS)). The devices in the IEEE 802.11 network are called nodes. The features of interest may include motion of objects and motion tracking, presence detection, intrusion detection, gesture recognition, fall detection, breathing rate detection, and other applications. The sensing space may refer to any physical space in which the WLAN sensing system may operate and may include a place of adobe, a place of work, a shopping mall, a sports hall or sports stadium, a garden, or any other physical space.

[0288] In the WLAN sensing network (e.g., IEEE 802.11 network), there may be one or more nodes that are AP devices and one or more nodes that are non-AP devices. Furthermore, the motion is determined in the sensing space by a sensing application on a device detecting perturbation in the local environment based on analysis of sensing measurements (for example, CSI) over time. A sensing transmission is sent from a sensing transmitter. A baseband Wi-Fi receiver (e.g., a sensing receiver) calculates the sensing measurement as a channel state measurement (e.g., CSI) consisting of a real and imaginary part for each element, or an in-phase (I) and quadrature (Q) part for each element, or an amplitude and phase part for each element. The CSI is passed via a Wi-Fi sensing agent to a sensing application at a higher layer to detect motion.

[0289] Furthermore, each link between a sensing transmitter and a sensing receiver is termed a sensing link. The sensing link may be under the control of a higher-layer sensing application on the sensing transmitter, the sensing receiver, and / or a separate sensing initiator. The sensing transmitter or sensing receiver may also act as the sensing initiator. Any of these three entities may be a non-AP STA or an AP. In some embodiments, a particular node may act as a sensing transmitter at one time point and as a sensing receiver at another time point. A sensing measurement session is a time period during which one or more sensing transmissions and corresponding sensing measurements are made. Furthermore, a sensing measurement session includes at least one or more sensing transmitters and at least one or more sensing receivers. A sensing measurement session is under the control of a sensing initiator which may be a higher-layer (e.g., above the PHY and MAC layers) sensing application. The sensinginitiator sends sensing measurement configurations to sensing transmitter(s) and / or sensing receiver(s) to provide parameters and any other required information for performing the sensing measurements.

[0290] Furthermore, IEEE 802.11be adds Multi-Link Operation (MLO) to earlier versions of the IEEE 802.11 standard. A multi-link device (MLD) may be an AP MLD or may be a non-AP MLD. An AP MLD may be capable of establishing multiple wireless links with another MLD. These multiple links may be used to improve performance by increasing aggregate data throughput and selecting the currently optimal link (e.g., lowest traffic loading). An MLD may include multiple STA entities, with one STA for each wireless link. These multiple STAs may operate on different frequencies and / or in different frequency bands. For example, an AP MLD may contain three AP entities, with one AP operating in the 2.4 GHz frequency band, another AP operating in the 5 GHz frequency band, and yet another AP operating in the 6 GHz band. Similarly, a non-AP MLD may also contain multiple (e.g., three) STA entities, with each STA potentially operating on a different frequency and / or in a different frequency band (e.g., one STA operating in the 2.4 GHz frequency band, another STA operating in the 5 GHz frequency band, and yet another STA operating in the 6 GHz band). Details on MLO and MLDs are explained in further paragraphs using FIG. 16

[0291] FIG. 16 depicts an exemplary MLO 1600 of two MLDs, according to some embodiments. In an embodiment, IEEE 802.11be adds MLO to earlier versions of the IEEE 802.11 standard. MLO 1600 may include multiple BSSs. In an embodiment, the wireless sensing network may include first AP MLD 1602, a second AP MLD (not shown), first non-AP MLD 1604 (alternatively known as ‘MLD STA’), a second non-AP MLD (not shown), and a third non-AP MLD (not shown). In an embodiment, an AP MLD corresponds to a network architecture that involves an access point supporting multiple links to various devices, particularly in scenarios like the Internet of Things (loT) or wireless sensor networks (WSNs). An MLD is capable of establishing multiple wireless communication links with another MLD. These multiple links may be used to improve the performance of the wireless sensing network by increasing aggregate data throughput, selecting the currently optimal (e.g., lowest traffic loading) link, and the like.

[0292] Referring to FIG. 16 in detail, first non-AP MLD 1604 may be associated with first AP MLD 1602. Furthermore, first AP MLD 1602 comprises two Access Points (APs) e.g., AP STA 1602A and AP STA 1602B. AP STA 1602A and AP STA 1602B may be affiliated with first AP MLD 1602. Each of these two AP STAs 1602A and 1602B may operate on a different frequency (or in a different frequency band) and / or with a different channel width. Forexample, AP STA 1602A may operate in the 2.4 GHz frequency band, and AP STA 1602B may operate in the 5 GHz frequency band. Similarly, first non-AP MLD 1604 also comprises two STAs e.g., non-AP STA 1604A and non-AP STA 1604B. Non-AP STA 1604A and non-AP STA 1604B may be affiliated with first non-AP MLD 1604. Furthermore, non-AP STA 1604A may have an established wireless link or data link 1606 with AP STA 1602A such that non-AP STA 1604A and AP STA 1602A may be communicably coupled with each other. Additionally, non-AP STA 1604B may also have an established wireless link or data link 1608 with AP STA 1602B such that non-AP STA 1604B and AP STA 1602B may be communicably coupled with each other. Furthermore, if the non-AP MLD (e.g., first non-AP MLD 1604) is an Enhanced Multi-Link Single Radio (EMLSR) (with a single radio), then it cannot operate concurrently on both first and second links (e.g., data link 1606 and data link 1608) at the same time. However, a non-AP EMLSR MLD may dynamically select between operations on the first and second links. Conversely, if the non-AP MLD is an Enhanced Multi-Link Multiple Radio (EMLMR) MLD (with multiple radios), then the non-AP MLD may operate concurrently on both the first and second links at the same time.

[0293] FIG. 16 provides an exemplary illustration of the EMLSR and the EMLMR concepts. EMLSR operation as defined in Section 35.3.17 of the IEEE 802.11be specification may allow the non-AP MLD (e.g., first non-AP MLD 1604) with multiple receive chains to communicate on one or more EMLSR links when the non-AP STAs (e.g., non-AP STA 1604A and non-AP STA 1604B) affiliated with the non-AP MLD are in the awake state. The EMLSR links may correspond to a set of wireless links or data links between the non-AP MLD and an AP MLD (e.g., first AP MLD 1602) that enables EMLSR mode. The EMLSR mode may allow dynamic and coordinated switching between the EMLSR links. The non-AP MLD (e.g., an EMLSR-enabled non-AP MLD) may dynamically select between operations on one of the multiple links. However, the non-AP MLD may not support concurrent (simultaneous) operation on multiple links and is thereby referred to as a single radio.

[0294] Furthermore, EMLMR operation as defined in Section 35.3.18 of the IEEE 802.11be / D5.0 specification may allow the non-AP MLD (e.g., first non-AP MLD 1604) with multiple radios on multiple links to communicate on a set of links between the non-AP MLD and its associated AP MLD (e.g., first AP MLD 1602). The EMLMR links may correspond to a set of wireless links or data links between the non-AP MLD and the AP MLD that enable EMLMR mode. The EMLMR mode may allow dynamic and coordinated switching between the EMLMR links. The non-AP MLD (e.g., an EMLMR-enabled non-AP MLD) may dynamically select between operations on one or more of the multiple links. Additionally, thenon-AP MLD (e.g., an EMLMR-enabled non-AP MLD) may support concurrent (simultaneous) operation on multiple links (e.g., data link 1606 and data link 1608) and is thereby referred to as a multiple radio.

[0295] FIG. 17 depicts an exemplary process 1700 of sharing sensing capabilities of links of an AP MLD, according to some embodiments. Process 1700 is used to share the sensing capabilities of the AP MLD with a non-AP MLD. For example, the AP MLD may be first AP MLD 1602 of FIG. 16. In an embodiment, the sensing capabilities may be shared by the AP MLD to a non-AP MLD. For example, the non-AP MLD may be first non-AP MLD 1604. In an implementation, flowchart 1700 may be carried out by networking devices (e.g., non-AP MLDs 504-(1-N) and AP MLD 502) participating in a sensing measurement session.

[0296] At step 1702, the AP MLD shares the availability of affiliated AP STAs (e.g., AP STA 1602A and AP STA 1602B affiliated with first AP MLD 1602) and support for WLAN sensing. In an embodiment, at least one of the AP STAs transmits a Beacon frame to share the availability of the AP STAs and support for WLAN sensing, as shown in step 1704. In an embodiment, the Beacon frame may correspond to an enhanced Beacon frame which includes the availability of the AP STAs. Upon the transmission of the enhanced Beacon frame, a discovery process to identify sensing capabilities is initiated. In an embodiment, each AP STA affiliated with the AP MLD may generate a Beacon frame that enables listening non-AP STAs to leam about BSS parameters and the AP STA which implements the BSS. In an embodiment, listening non-AP STAs may be client devices (such as laptops or smartphones) that may be actively searching for available wireless networks. The Beacon frame may also provide basic information about other AP STAs affiliated with the AP MLD. Details on the format of the enhanced Beacon frame have been explained with reference to at least FIG. 18.

[0297] Furthermore, at step 1706, the non-AP MLD (e.g., first non-AP MLD 1604) requests sensing capabilities of the AP STAs affiliated with the AP MLD. The sensing capabilities of the AP STAs may correspond to whether the links associated with the AP STAs support sensing. To request the sensing capabilities of the AP STAs (e.g., the sensing capabilities of links associated with the AP STAs), at least one of the non-AP STAs affiliated with a non-AP MLD (e.g., non-AP STA 1604A and non-AP STA 1604B affiliated with first non-AP MLD 1604) may transmit a Probe Request frame as shown in step 1708. In an embodiment, the Probe Request frame may correspond to an enhanced Probe Request frame configured to request the sensing capabilities of the AP STAs.

[0298] At step 1710, the AP MLD provides the sensing capabilities of the AP STAs affiliated with the AP MLD to the non-AP MLD. To provide the sensing capabilities of the APSTAs to the non-AP MLD, the AP STAs transmit a Probe Response frame as shown in step 1712. In an embodiment, the Probe Response frame may correspond to an enhanced Probe Response frame configured to provide the sensing capabilities of the AP STAs.

[0299] FIG. 18 depicts an exemplary enhanced Beacon frame 1800 which supports communication of support for WLAN sensing by the AP MLD, according to some embodiments. FIG. 18 shows elements that may be important to the communication of support for WLAN sensing by MLDs.

[0300] In an embodiment, an existing Beacon frame may be defined by P802.11REVme, P802.11be, and P802.11bf An AP STA of the AP STAs may generate enhanced Beacon frame 1800. Furthermore, the AP STA (e.g., the AP STA affiliated with the AP MLD) may transmit enhanced Beacon frame 1800 to a non-AP MLD. Upon receiving enhanced Beacon frame 1800, the non-AP MLD may determine BSS parameters and basic information associated with each of the AP STAs.

[0301] As shown in FIG. 18, enhanced Beacon frame 1800 may include one or more of an Extended Capabilities element field, a Reduced Neighbor Report element field, and a Basic Multi-Link element field. The Extended Capabilities element may describe the capabilities of the AP STA (e.g., the AP STA which transmits enhanced Beacon frame 1800). IEEE P802.11bf / D4.0 defines that bit 106 of the Extended Capabilities element may be set when WLAN sensing is supported by the AP STA.

[0302] Furthermore, the Reduced Neighbor Report element may describe the capabilities of other AP STAs affiliated with the AP MLD which implemented the AP STA that transmits enhanced Beacon frame 1800. Each of the AP STAs (e.g., the AP STA which transmits the enhanced Beacon frame and the other AP STAs) may be referenced by a Link ID, such that each Link ID associated with the AP MLD may be a unique value. For example, when there are n AP STAs affiliated with the AP MLD, the AP STA which transmits enhanced Beacon frame 1800 may be assigned a Link ID 0 and the other AP STAs are assigned Link IDs 1, 2,... n - 1. Details of the Reduced Neighbor Report element and the Basic Multi-Link element have been explained in further paragraphs using FIG. 19.

[0303] FIG. 19 depicts an exemplary enhanced MLD parameters subfield format 1900 to support WLAN sensing, according to some embodiments. In an embodiment, P802.11be / D5.0 describes that a Reduced Neighbor Report element with a Target Beacon Transmission Time (TBTT) Information Length subfield value of 16 includes an MLD Parameters subfield. The MLD Parameters subfield is modified to signal that the AP STAs affiliated with the AP MLD may support WLAN sensing.

[0304] Referring to FIG. 19 in detail, a ‘Sensing’ subfield is added at bit position B22 in enhanced MLD Parameters subfield format 1900. In an embodiment, a size associated with the Sensing subfield may correspond to one bit of data, such that the Sensing subfield is set to 1 to indicate that WLAN sensing is supported by the AP STAs (e.g., the AP STAs affiliated with the AP MLD). Furthermore, the Sensing subfield may be set to 0 to indicate that WLAN sensing is not supported by the AP STAs. In an embodiment, a larger size of the MLD Parameters subfield may be defined and support for WLAN sensing may be described by three bits of data. In this scenario, the settings of these three bits of data may be as summarized in Table 1.

[0305] In another embodiment, a size associated with enhanced MLD parameters subfield format 1900 may be increased from three octets to four octets and the remaining unused bits (e.g., B25 to B31) may be reserved.

[0306] The Basic Multi-Link element of enhanced Beacon frame 1800 in FIG. 18 may include information that is common to the AP MLD. In an embodiment, the Common Info field of the Basic Multi-Link element may include no additional information related to WLAN sensing and the sensing capabilities of the AP MLD when transmitted in enhanced Beacon frame 1800. In another embodiment, a single bit of information may be transmitted in the Common Info field which signals that the AP MLD supports WLAN sensing. In both of the above embodiments, the detail associated with the AP STAs (AP STAs affiliated with the AP MLD) that may support WLAN sensing may be carried by the Extended Capabilities element (e.g., details associated with the AP STA that transmits enhanced Beacon frame 1800) and the Reduced Neighbor Report element (e.g., details associated with the other AP STAs that are different from the AP STA).

[0307] Enhanced Beacon frames (e.g., enhanced Beacon frame 1800) may be transmited by each of the AP STAs affiliated with the AP MLD at a rate determined by AP MLD configuration. Furthermore, each of the enhanced Beacon frames may describe an AP STA that may transmit the corresponding enhanced Beacon frame and the other AP STAs different from the AP STA. Thus, Beacon frames transmited by any AP STA affiliated with the AP MLD are capable of providing sufficient information to describe all AP STAs associated with the AP MLD as outlined above. In an embodiment, a non-AP STA affiliated with the non-AP MLD (e.g., non-AP STA 1604A or non-AP STA 1604B affiliated with first non-AP MLD 1604) may receive all the transmited enhanced Beacon frames and may select an AP STA from the AP STAs to request the sensing capability of the AP MLD.

[0308] The non-AP STA may transmit a Probe Request frame to the AP MLD. Furthermore, a configured Probe Request frame may allow the non-AP MLD to request more detailed information on an AP MLD’s support for WLAN sensing. In an embodiment, the Probe Request frame may be sent to any AP MLD irrespective of whether a Beacon frame has been received and processed. The Probe Request frame may be transmited by a single non-AP STA affiliated with the non-AP MLD and may be addressed to a single AP STA affiliated with the AP MLD. In an embodiment, the Probe Request frame of a conventional system is described by P802.11REVme, P802.11be, and P802.11bf. An example of a format of an enhanced Probe Request frame is shown in FIG. 20.

[0309] FIG. 20 depicts an exemplary enhanced multi-link Probe Request frame 2000 transmited during MLO discovery, according to some embodiments. FIG. 20 shows elements that may be important to the communication of support for WLAN sensing by MLDs.

[0310] In an embodiment, enhanced multi-link Probe Request frame 2000 may request information from an AP MLD. Enhanced multi-link Probe Request frame 2000 may be addressed to (and received by) a single AP STA affiliated with the AP MLD. Enhanced multilink Probe Request frame 2000 addressed to the AP STA may request WLAN sensing information about the AP MLD and the AP STAs (e.g., the AP STAs affiliated with the AP MLD).

[0311] Referring to FIG. 20 in detail, multi -link Probe Request frame 2000 may include a Probe Request Multi-Link element which includes a Common Info field and one Per-STA Profile Link ID sub-element for each AP STA affiliated with the AP MLD. In an embodiment, when there are n AP STAs affiliated with the AP MLD there may be n Per-STA Profile Link ID sub-elements.

[0312] For example, the Common Info field may include an AP MLD ID associated with the AP MLD including the AP STA that may receive enhanced multi-link Probe Request frame 2000. Furthermore, each of the Per-STA Profile Link ID sub-elements may include Link IDs of each of the AP STAs for which multi-link device information, including WLAN sensing information, is required. The Per-STA Profile Link ID sub-elements may specify that complete or partial information about each AP STA is required. The WLAN sensing information may be delivered in response to multi-link Probe Request frame 2000 in either situation (i.e., when either complete or partial information about each AP STA is required).

[0313] In another embodiment, the Per-STA Profile Link ID sub-elements may not be present in enhanced multi-link Probe Request frame 2000, such that enhanced multi-link Probe Request frame 2000 is interpreted as requesting complete MLD information (including the WLAN sensing information) from all the AP STAs referenced by the AP MLD ID in the Common Info field.

[0314] In yet another embodiment, a single AP STA affiliated with the AP MLD may be selected by the transmitter of a Probe Request frame from which to request the sensing capability of the AP MLD. In yet another embodiment, the AP STAs affiliated with the AP MLD may be queried and a single AP MLD may be selected based on the query.

[0315] In response to enhanced multi-link Probe Request frame 2000, the AP MLD may send a Probe Response frame including information on the sensing capabilities (e.g., the WLAN sensing capabilities) of the AP MLD, including the sensing capabilities of each of the AP STAs affiliated with the AP MLD.

[0316] In an embodiment, the Probe Response frame of a conventional system is described by P802.11REVme, P802.11be, and P802.11bf. An example of a format of an enhanced Probe Response frame is shown in FIG. 21.

[0317] FIG. 21 depicts an exemplary enhanced multi-link Probe Response frame 2100 describing the sensing capabilities (e.g., the WLAN sensing capabilities) of an AP MLD, according to some embodiments. Enhanced multi-link Probe Response frame 2100 may be transmitted by the AP affiliated with the AP MLD which may be addressed by enhanced multilink Probe Request frame 2000.

[0318] Referring to FIG. 21 in detail, enhanced multi-link Probe Response frame 2100 may include WLAN sensing information about the AP MLD and the AP STAs affiliated with the AP MLD. Furthermore, a Sensing Capabilities element may be present in enhanced multilink Probe Response frame 2100. The Sensing Capabilities element may describe the sensing capabilities of the affiliated AP STA that may transmit enhanced multi-link Probe Responseframe 2100. Additionally, a Reduced Neighbor Report element may be present in enhanced multi-link Probe Response frame 2100. The Reduced Neighbor Report element may describe the AP STAs different from the AP STA that transmits enhanced multi-link Probe Response frame 2100. The Reduced Neighbor Report element may include the Link IDs associated with the AP STAs different from the AP STA that transmits enhanced multi-link Probe Response frame 2100. In an embodiment, there may be atotal of n AP STAs affiliated with the AP MLD. Thus, the Reduced Neighbor Report element may describe n — 1 AP STAs except for the AP STA that transmits enhanced multi -link Probe Response frame 2100.

[0319] Furthermore, a Basic Multi-Link element may be further present in enhanced multi-link Probe Response frame 2100. The Basic Multi -Link element may include a Common Info field. The Common Info field describes the sensing capabilities of the AP MLD. The Basic Multi-Link element may include a Link Info field. In an embodiment, the Link Info field may describe the sensing capabilities of each of the affiliated AP MLDs referred to by a link ID. The Link Info field may further include at least one or more Per-STA Profile sub-elements such that at least one or more Per-STA Profile sub-elements may describe details of each of the AP STAs except the AP STA that transmits enhanced multi-link Probe Response frame 2100.

[0320] In an embodiment, the Common Info field of a conventional system is described by P802.11be / D5.0. An example of a format of an enhanced Common Info field is shown in FIG. 22.

[0321] FIG. 22 depicts an exemplary enhanced Common Info field 2200 of the Basic Multi-Link element which supports communication of the sensing capabilities (e.g., the WLAN sensing capabilities) of an MLD (e.g., the AP MLD), according to some embodiments.

[0322] Common Info field 2200 may include an MLD Sensing Capabilities subfield when the AP MLD supports WLAN sensing. The presence of the MLD Sensing Capabilities subfield may be signalled by setting a bit in a Presence Bitmap subfield in a Multi-Link Control field in the Basic Multi-Link element. An example of an enhanced Presence Bitmap subfield is shown in FIG. 23. A Link Group ID subfield may include a Link Group ID associated with the AP MLD. The Link Group ID has been explained in further paragraphs using FIG. 31.

[0323] FIG. 23 depicts an exemplary enhanced Presence Bitmap subfield 2300 of the Basic Multi-Link element which supports the communication of the sensing capabilities of the MLD (e.g., the AP MLD), according to some embodiments.

[0324] Referring to FIG. 23 in detail, setting bit B7 corresponding to the Sensing Capabilities Present subfield in enhanced Presence Bitmap subfield 2300 to 1 indicates that theCommon Info sub-element in the Basic Multi-Link element contains the WLAN sensing information for the AP MLD. In another embodiment, if bit B7 is set to 0 then the WLAN sensing information (e.g., an MLD Sensing Capabilities subfield) is not present in the Common Info field of the Basic Multi-Link element.

[0325] Furthermore, the MLD Sensing Capabilities subfield may describe the sensing capabilities of the MLD (versus the sensing capabilities of the associated AP STAs or the non-AP STAs). The MLD Sensing Capabilities subfield may include a single bit of information that signals that the AP MLD supports WLAN sensing. The MLD Sensing Capabilities subfield may further include descriptions of types of sensing transmissions or sensing measurements that may be supported. For example, it may include that wideband, high-resolution measurements may be supported.

[0326] The STA Control field and the STA Info field carried by the Per-STA Profile subelement may be enhanced to include the WLAN sensing information. The format of the Per-STA Profile sub-element may be as defined by P802.11be. An example of the format of an enhanced STA Info field is shown in FIG. 24.

[0327] FIG. 24 depicts an exemplary enhanced STA Info field format 2400 of the per-STA profile sub-element of the Basic Multi-Link element which supports the communication of sensing capabilities of the AP STA affiliated with the AP MLD, according to some embodiments.

[0328] Referring to FIG. 24 in detail, a STA Sensing Capabilities subfield is present in enhanced STA Info field format 2400 when the AP STA affiliated with the AP MLD supports WLAN sensing. The presence of the STA Sensing Capabilities subfield may be signalled by setting a bit in a STA Control field in the Per-STA Profile sub-element that contains enhanced STA Info field format 2400.

[0329] FIG. 25 depicts an exemplary enhanced STA Control field format 2500 of the Basic Multi-Link element which supports the communication of the sensing capabilities of the STA affiliated with the MLD.

[0330] Referring to FIG. 25 in detail, setting bit B12 corresponding to the Sensing Capabilities Present subfield in enhanced STA Control field format 2500 to 1 may indicate that the Per-STA Profile sub-element in the Link Info field of the Basic Multi-Link element may include the sensing information for the AP STA (e.g., affiliated AP) referenced by the Link ID. In another embodiment, if bit B12 is set to 0 then sensing information (e.g., a Per-STA Profile sub-element) may not be present in the Link Info field of the Basic Multi-Link element.Furthermore, an example of the STA Sensing Capabilities subfield carried by each of the Per-STA Profile sub-element is shown in FIG. 26.

[0331] FIG. 26 depicts an exemplary STA Sensing Capabilities subfield format 2600, according to some other embodiments. In an embodiment, STA Sensing Capabilities subfield format 2600 may be carried by each of the Per-STA Profile sub-elements.

[0332] Referring to FIG. 26 in detail, STA Sensing Capabilities subfield format 2600 may have the same format as the Sensing subfield contained in the Sensing Capabilities element as defined by P802.11bf / D4.0. FIG. 26 may be a reproduction of Figure 9-1072bj in P802.11bf / D4.0. In an embodiment, the size of the STA Sensing Capabilities subfield format 2600 may be nine octets. In other embodiments, the size of STA Sensing Capabilities subfield format 2600 may vary depending on the exact contents of STA Sensing Capabilities subfield 2600.

[0333] In an embodiment, various other examples of sensing capabilities may be included in STA Sensing Capabilities subfield format 2600, such as a DMG Sensing Capabilities element, a DMG Sensing Beam Descriptor element, a DMG Sensing Short Capabilities element, and the like. The size in octets of STA Sensing Capabilities subfield format 2600 may be adjusted accordingly. Furthermore, the presence of the differing types of STA sensing capabilities may be signalled by bits in the enhanced STA Control field.

[0334] FIG. 27 depicts an exemplary process 2700 to (re)associate a non-AP MLD and an AP MLD and to share the sensing capabilities of links of the non-AP MLD, according to some embodiments.

[0335] In an embodiment, after the discovery process shown in FIG. 17, the non-AP MLD may have determined (e.g., learned) the sensing capabilities of the AP MLD (e.g., the sensing capabilities of the links of the AP MLD). Furthermore, the non-AP MLD may associate with the AP MLD to exchange data and to perform WLAN sensing by the transmission and reception of sensing transmissions and the calculation and sharing of sensing measurements (e.g., WLAN sensing measurements). As part of a (re)association process, the non-AP MLD may share its sensing capabilities with the AP MLD. In an embodiment, the non-AP MLD may (re)associate with the AP MLD by communicating between any one affiliated non-AP MLD STA and any one affiliated AP MLD STA.

[0336] In an implementation, flowchart 2700 may be carried out by the non-AP MLD. At step 2702, the non-AP STA (e.g., the non-AP STA affiliated with the non-AP MLD) may authenticate with the AP STA (e.g., the AP STA affiliated with the AP MLD). In an embodiment, to authenticate with the AP STA, the non-AP STA may transmit anAuthentication frame to the AP STA as shown in step 2704. At step 2706, the non-AP MLD may initialize (re)association of one or more affiliated non-AP STAs with associated AP STAs. In an embodiment, to initialize (re)association with the AP STAs, the non-AP STA may transmit a (Re)Association Request frame to the AP STA. At step 2710, the AP MLD may confirm (re)association with one or more non-AP STAs affiliated with the non-AP MLD. In an embodiment, to confirm (re)association with one or more non-AP STAs, the AP MLD may transmit a (Re)Association Response frame. At step 2714, the non-AP MLD and the AP MLD may perform a 4-way handshake as described by P802.11REVme.

[0337] In an embodiment, a non-AP STA affiliated with a single non-AP MLD and an AP STA affiliated with a single AP MLD are selected by the non-AP MLD to perform the (re)association process. Furthermore, the non-AP STA affiliated with the non-AP MLD and the AP STA affiliated with the single AP MLD authenticate each other by sharing authentication messages. In an embodiment, a standardized process to authenticate may be described by P802.11REVme and may be used for this step. Furthermore, the non-AP STA affiliated with the non-AP MLD may transmit a (Re)Association Request frame to the AP STA affiliated with the AP MLD. In an embodiment, a suitably configured (Re)Association Request frame may allow a non-AP MLD to share information on a non-AP MLD’s support for WLAN sensing. The (Re)Association Request frame may be sent to any AP MLD irrespective of whether a Beacon frame or a Probe Response has been received and processed from the corresponding AP STA.

[0338] In an embodiment, the (Re)Association Request frame of the conventional system is described by P802.11REVme, P802.11be, and P802.11bf. An example of a format of an enhanced (Re)Association Request frame is shown in FIG. 28.

[0339] FIG. 28 depicts an exemplary format of an enhanced (Re)Association Request frame and an enhanced (Re)Association Response frame transmitted by the affiliated STA of the MLD, according to some embodiments. For the sake of brevity, elements that may be important to the communication of support for WLAN sensing by MLDs may be shown in FIG. 28.

[0340] In an embodiment, the format of each of the enhanced (Re)Association Request frames and an enhanced (Re)Association Response frame is shown using 2800.

[0341] The non-AP STA (e.g., the non-AP STA affiliated with the non-AP MLD) may generate an enhanced (Re)Association Request frame. The enhanced (Re)Association Request frame may include a Sensing Capabilities element that describes the sensing capability (e.g., the WLAN sensing capability) of the non-AP STA (e.g., the non-AP STA affiliated with thenon-AP MLD) that transmits the enhanced (Re)Association Request frame. In another embodiment, one or more of a DMG Sensing Capabilities element (not shown), a DMG Sensing Beam Descriptor element (not shown), and a DMG Sensing Short Capability element (not shown) may be present in the enhanced (Re)Association Request frame. The format of the Sensing Capabilities element (and optional elements such as the DMG Sensing Capabilities element, the DMG Sensing Beam Descriptor element, and the DMG Sensing Short Capability element) may be as described by P802.11bf.

[0342] Furthermore, a Basic Multi-Link element may be included in the enhanced (Re)Association Request frame. The Basic Multi-Link element may describe the sensing capability of the non-AP MLD including the other affiliated non-AP STAs that are not transmitting enhanced (Re)Association Request frame 2800. The format of the Basic MultiLink element is described in FIG. 21. In the Basic Multi-Link element as used by enhanced (Re)Association Request frame 2800, the MLD may refer to the non-AP MLD and the STAs may refer to the non-AP STAs (e.g., the non-AP STAs affiliated with the non-AP MLD).

[0343] Upon the generation of the enhanced (Re)Association Request frame, the non-AP STA affiliated with the AP MLD may transmit enhanced (Re)Association Request frame 2800. In an embodiment, the AP STA may receive the enhanced (Re)Association Request frame. In response to the enhanced (Re)Association Request frame, the AP STA may transmit an enhanced (Re)Association Response frame to the non-AP STA. The format of the enhanced (Re)Association Response frame is as shown by 2800. In an embodiment, the enhanced (Re)Association Response frame may include information on the WLAN sensing capabilities of the AP MLD, including the WLAN sensing capabilities of each of the AP STAs (e.g., the AP STAs affiliated with the AP MLD). In an embodiment, the format of the enhanced (Re)Association Response frame may be identical to the enhanced (Re)Association Request frame. Furthermore, the enhanced (Re)Association Request frame may include a Sensing Capabilities element that describes the sensing capability (e.g., the WLAN sensing capability) of the AP STA (e.g., the AP STA affiliated with the AP MLD) that transmits the enhanced (Re)Association Response frame. In another embodiment, one or more of a DMG Sensing Capabilities element (not shown), a DMG Sensing Beam Descriptor element (not shown), and a DMG Sensing Short Capability element (not shown) may be present in the enhanced (Re)Association Response frame.

[0344] Additionally, although information carried (e.g., the sensing capability of the AP STA) by the enhanced (Re)Association Response frame may be similar to information carried by enhanced multi -link Probe Response frame 2100 in FIG. 21, the process as described mayallow the complete sensing information of the AP MLD and the non-AP MLD to be shared during the (re)association process. The sharing of the complete sensing information of the AP MLD and the non-AP MLD may be without the requirement to have received and processed any messages during the discovery process shown in FIG. 17.

[0345] Furthermore, the 4-way handshake may be performed between the non-AP MLD and the AP MLD to complete the (re)association process. In an embodiment, the 4-way handshake may be as described by P802.11REVme.

[0346] FIG. 29 depicts an exemplary process 2900 of sharing the sensing capabilities of links of an AP MLD and a non-AP MLD without association, according to some embodiments.

[0347] In an embodiment, sensing with unassociated STAs may correspond to a mechanism by which sensing transmissions can be configured and made without the sensing transmitter and sensing receiver being associated in the BSS. Sensing with unassociated MLDs may correspond to an extension of a mechanism described by the present disclosure where sensing is carried out between MLDs that may be unassociated. Sensing with the unassociated MLDs may provide suitable flexibility to WLAN sensing where it is supported.

[0348] To initiate or to allow the configuration of sensing with unassociated MLDs, the AP MLD and the non-AP MLD may be required to understand the sensing capabilities of each other. Each of the AP MLD and the non-AP MLD may be required to understand the sensing capabilities without being associated with each other. To support the configuration of sensing with the unassociated MLDs, the discovery process using an enhanced Beacon frame (e.g., enhanced Beacon frame 1800 in FIG. 18), an enhanced Probe Request frame (e.g., enhanced multi-link Probe Request frame 2000 in FIG. 20), and an enhanced Probe Response frame (e.g., enhanced multi-link Probe Response frame 2100 in FIG. 21) may be enhanced.

[0349] In an implementation, flowchart 2900 may be carried out by the networking device (e.g., non-AP MLDs 504-(1-N) and AP MLD 502) operating as the station and participating in the sensing measurement session. Flowchart 2900 may describe a second process to share the sensing capabilities of both the AP MLD and the non-AP MLD with each other.

[0350] At step 2902, the AP MLD shares the availability of the AP STAs (e.g., the AP STAs affiliated with AP MLD) and support for WLAN sensing. In an embodiment, to share the availability of the AP STAs and support for WLAN sensing, at least one of the AP STAs transmits a Beacon frame as shown in step 2904. In an embodiment, the transmitted Beacon frame may correspond to an enhanced Beacon frame (e.g., enhanced Beacon frame 1800) to include the availability of the AP STAs. Upon the transmission of the enhanced Beacon frame, a discovery process to identify the sensing capabilities is initiated.

[0351] At step 2906, the non-AP MLD requests the sensing capabilities of the AP STAs. The sensing capabilities of the AP STAs may correspond to whether the links associated with the AP STAs support sensing. Additionally, the non-AP MLD may share the sensing capabilities of the non-AP STAs (e.g., the non-AP STAs affiliated with the non-AP MLD). In an embodiment, to request the sensing capabilities of the AP STAs (e.g., the sensing capabilities of links associated with the AP STAs) and to share the sensing capabilities of the non-AP STAs (e.g., the sensing capabilities of links associated with the non-AP STAs), at least one of the non-AP STAs affiliated with the non-AP MLD may transmit a Probe Request frame as shown in step 2908. In an embodiment, the transmitted Probe Request frame may correspond to an enhanced Probe Request frame configured to request the sensing capabilities of the AP STAs.

[0352] At step 2910, the AP MLD provides the sensing capabilities of the AP STAs (e.g., the AP STAs affiliated with AP MLD) to the non-AP MLD. In an embodiment, to provide the sensing capabilities of the AP STAs to the non-AP MLD, the AP STAs transmit a Probe Response frame as shown in step 2912. In an embodiment, the transmitted Probe Response frame may correspond to an enhanced Probe Response frame to provide the sensing capabilities of the AP STAs.

[0353] The steps of flowchart 2900 may be identical to the steps of flowchart 1700 (to share the sensing capabilities of links of the AP MLD) except that the Probe Request frame sent in step 2902 may be modified to include the sensing capabilities of the non-AP MLD that may transmit the Probe Request frame as shown in FIG. 29. For the sake of brevity, elements that may be important to the communication of support for WLAN sensing by the MLDs may be shown in FIG. 30.

[0354] FIG. 30 depicts an exemplary enhanced Probe Request frame 3000 supporting the transmission of sensing information of the issuing non-AP MLD, according to some embodiments.

[0355] In an embodiment, enhanced Probe Request frame 3000 may include a Probe Request Multi-Link element. The Probe Request Multi-Link element may include a Common Info field and one Link Info field for each AP STA of the AP STAs (e.g., the AP STAs affiliated with the AP MLD). If there are n AP STAs affiliated with the AP MLD then there may be n Link Info fields within the Probe Request Multi-Link element. Furthermore, enhanced Probe Request frame 3000 may be as described in step 1708 of flowchart 1700. Enhanced Probe Request frame 3000 may further include a Basic Multi-Link element which may describe the sensing capabilities of the non-AP MLD issuing enhanced Probe Request frame 3000. Theformat and content of the Basic Multi-Link element may be as described in FIG. 21. An example of a STA Sensing Capabilities subfield carried by each Per-STA Profile is shown in FIG. 26.

[0356] In one example, the sharing of the capabilities of the non-AP MLD described above may be limited to only the sensing capabilities of the MLDs. To support this, the Basic MultiLink element may contain information related only to WLAN sensing (e.g., no information relating to other aspects of MLO and the MLDs) and the Common Info field (e.g., Common Info field 2200) carried by the Basic Multi-Link element may contain only a Link ID Info field and a MLD Sensing Capabilities and Operations subfield as shown in FIG. 22. The STA Info field in the Link ID Info field may contain only the STA MAC Address and STA Sensing Capabilities fields. The Presence Bitmap subfield in the Multi-Link Control field and the STA Control field in a Link Info field may be configured to support the transfer of only the WLAN sensing capabilities.

[0357] FIG. 31 depicts an exemplary WLAN sensing network 3100 including three MLDs, according to some embodiments. The three MLDs may be present in sensing space 3102.

[0358] Referring to FIG. 31 in detail, sensing space 3102 may include AP MLD 3104, first non-AP MLD 3106, and second non-AP MLD 3108. In an embodiment, AP MLD 3104 may include three affiliated AP STAs (not shown). Furthermore, first non-AP MLD 3106 may include three affiliated non-AP STAs (not shown), and second non-AP MLD 3108 may include two affiliated non-AP STAs (not shown). Thus, three links may exist between AP MLD 3104 and first non-AP MLD 3106. Additionally, two links may exist between AP MLD 3104 and second non-AP MLD 3108. For the sake of brevity, the links between AP MLD 3104 and each of first non-AP MLD 3106 and second non-AP MLD 3108 may be hereinafter referred to as “sensing links”. The WLAN network may be used for WLAN sensing (and may be described as a WLAN sensing network). In an example, the WLAN network may be configured explicitly for WLAN sensing. In another example, the WLAN network may be configured for data transfer between connected STAs and a data network, and WLAN sensing may be initiated in parallel with data transfer functionality.

[0359] In an embodiment, AP MLD 3104 may correspond to an EMLMR MLD such that AP MLD 3104 may comprise a plurality of radios (not shown). Furthermore, AP MLD 3104 may operate concurrently on multiple sensing links at the same time. AP MLD 3104 may be configured to transmit a plurality of Beacon frames by the plurality of radios including information about AP MLD 3104. In an embodiment, the plurality of radios may correspond to the three AP STAs affiliated with AP MLD 3104. For example, the three AP STAs affiliatedwith AP MLD 3104 may each broadcast (e.g., transmit) a Beacon frame (e.g., enhanced Beacon frame 1800 in FIG. 18) advertising a BSS, the AP STA that may transmit the corresponding Beacon frame, AP MLD 3104, and the two other AP STAs affiliated with AP MLD 3104. In an embodiment, the Beacon frame may be configured to indicate that each of the three AP STAs may be affiliated with AP MLD 3104 and may support sensing (e.g., WLAN sensing).

[0360] Furthermore, each Beacon frame may be received by respective non-AP STAs of both first non-AP MLD 3106 and second non-AP MLD 3108 (e.g., non-AP STAs affiliated with first non-AP MLD 3106 and second non-AP MLD 3108). For example, a Beacon frame transmitted by an AP STA in the 2.4 GHz transmission band is received by a non-AP STA configured to receive in the 2.4 GHz band. In an embodiment, as second non-AP MLD 3108 may implement only two affiliated non-AP STAs, second non-AP MLD 3108 may only receive Beacon frames transmitted by two AP STAs affiliated with AP MLD 3104. For example, second non-AP MLD 3108 may implement only two affiliated non-AP STAs. Thus, the Beacon frame transmitted by the third AP STA affiliated with AP MLD 3104 may not be received by second non-AP MLD 3108.

[0361] In an embodiment, each Beacon frame may include the MAC address of AP MLD 3104, AP MLD ID associated with AP MLD 3104, or the like. Based on the Beacon frame (e.g., the MAC address of AP MLD 3104, the AP MLD ID associated with AP MLD 3104, or the like), first non-AP MLD 3106 and second non-AP MLD 3108 may determine one or more AP STAs of the AP STAs affiliated with AP MLD 3104. In an embodiment, first non-AP MLD 3106 may transmit a first Probe Request frame from one of the non-AP STAs affiliated with first non-AP MLD 3106 that may have received a Beacon frame. Additionally, second non-AP MLD 3108 may transmit a second Probe Request frame from one of the non-AP STAs affiliated with second non-AP MLD 3108 that may have received a Beacon frame. In an embodiment, the non-AP STAs affiliated with first non-AP MLD 3106 and second non-AP MLD 3108 over which the first Probe Request frame and the second Probe Request frame are transmitted may have been selected by first non-AP MLD 3106 and second non-AP MLD 3108, respectively.

[0362] Upon the transmission of the first Probe Request frame and the second Probe Request frame, AP MLD 3104 may be further configured to receive the first Probe Request frame and the second Probe Request frame from first non-AP MLD 3106 (e.g., the non-AP STAs affiliated with first non-AP MLD 3106) and second non-AP MLD 3108 (e.g., the non-AP STAs affiliated with second non-AP MLD 3108), respectively. Each of the first Probe Request frame and the second Probe Request frame may be configured to request detailed sensing capabilities from AP MLD 3104, including sensing capabilities of each of the AP STAsaffiliated with AP MLD 3104. Furthermore, the AP STAs receiving the first Probe Request frame and the second Probe Request frame may generate a first Probe Response frame and a second Probe Response frame in response to the first Probe Request frame and the second Probe Request frame, respectively.

[0363] In an embodiment, AP MLD 3104 may be further configured to transmit the first Probe Response frame and the second Probe Response frame that may include the sensing capabilities (e.g., the detailed sensing capabilities) of AP MLD 3104. Additionally, each of the first Probe Response frame and the second Probe Response frame may include detailed sensing capabilities of each of the AP STAs affiliated with AP MLD 3104. In an embodiment, the AP STAs may transmit the first Probe Response frame and the second Probe Response frame generated by the corresponding AP STA.

[0364] Upon transmission of the first Probe Response frame and the second Probe Response frame, the non-AP STAs affiliated with first non-AP MLD 3106 and second non-AP MLD 3108 may receive each of the Probe Response frames from the corresponding AP STA. In an embodiment, a non-AP STA of the non-AP STAs receiving the first Probe Response frame and an AP STA of the AP STAs transmitting the first Probe Response frame may authenticate with each other. Additionally, a non-AP STA of the non-AP STAs receiving the second Probe Response frame and an AP STA of the AP STAs transmitting the second Probe Response frame may authenticate with each other. In an embodiment, authentication with one of the AP STAs affiliated with AP MLD 3104 may be performed for each of the non-AP STAs affiliated with first non-AP MLD 3106 and each of the non-AP STAs affiliated with second non-AP MLD 3108.

[0365] Furthermore, the non-AP STAs receiving the first Probe Response frame or the second Probe Response frame may generate a first Association Request frame or a second Association Request frame, respectively. The non-AP STAs may further transmit the first Association Request frame or the second Association Request frame to the corresponding AP STA that transmitted the first Probe Response frame or the second Probe Response frame. The first Association Request frame may be configured to associate a non-AP STA affiliated with first non-AP MLD 3106 and the corresponding AP STA. Additionally, the second Association Request frame may be configured to associate a non-AP STA affiliated with second non-AP MLD 3108 and the corresponding AP STA. In an embodiment, the first Association Request frame may be further configured to reassociate the non-AP STA affiliated with first non-AP MLD 3106 and the corresponding AP STA; thus the first Association Request frame may alternatively be referred to as a first (Re)Association Request frame. Additionally, the secondAssociation Request frame may be further configured to reassociate the non-AP STA affiliated with second non-AP MLD 3108 and the corresponding AP STA; thus the second Association Request frame may alternatively be referred to as a second (Re)Association Request frame. In an embodiment, the first Association Request frame and the second Association Request frame may transmit the sensing capabilities of first non-AP MLD 3106 and second non-AP MLD 3108, and each of the non-AP STAs affiliated with first non-AP MLD 3106 and second non-AP MLD 3108, respectively.

[0366] In an embodiment, AP MLD 3104 may be configured to receive the first Association Request frame from first non-AP MLD 3106 (e.g., the non-AP STA affiliated with first non-AP MLD 3106). In an embodiment, the first Association Request frame may include the MAC address of first non-AP MLD 3106, the MAC addresses of the non-AP STAs affiliated with first non-AP MLD 3106, the MLD ID of first non-AP MLD 3106, the Link IDs associated with the non-AP STAs affiliated with first non-AP MLD 3106, or additional data. Thus, AP MLD 3104 may determine the identity of associations between the AP STAs affiliated with AP MLD 3104 and corresponding non-AP STAs affiliated with first non-AP MLD 3106 based on the first Association Request frame. In an embodiment, the first Association Request frame (e.g., the additional data in the first Association Request frame) may include the sensing capabilities of one or more non-AP STAs affiliated with first non-AP MLD 3106. Furthermore, AP MLD 3104 may store the sensing capabilities of one or more non-AP STAs affiliated with first non-AP MLD 3106 in data storage (e.g., Link Group ID storage 522 as shown in FIG. 5) or memory.

[0367] In an embodiment, first Link Group ID 3110 may be defined which provides a unique identifier for all AP STA-to-non-AP STA links (e.g., sensing links) between AP MLD 3104 and first non-AP MLD 3106. In other words, a first link group may be identified and given a unique Link Group ID (e.g., first Link Group ID 3110) by AP MLD 3104. In an embodiment, first Link Group ID 3110 identifies multi-links between AP MLD 3104 and first non-AP MLD 3106. In additional embodiments, first Link Group ID 3110 identifies multilinks that support sensing between AP MLD 3104 and first non-AP MLD 3106.

[0368] Furthermore, AP MLD 3104 may be configured to assign first Link Group ID 3110 to first non-AP MLD 3106 (or assign first Link Group ID 3110 to the three links between AP MLD 3104 and first non-AP MLD 3106). AP MLD 3104 may assign (or allocate) first Link Group ID 3110 when first non-AP MLD 3106 associates with AP MLD 3104. In an embodiment, first Link Group ID 3110 may be unique to AP MLD 3104 at a particular time (i.e., the value of first Link Group ID 3110 may refer only to the three links between AP MLD3104 and first non-AP MLD 3106 during a particular period of time and may not refer to any other links between AP MLD 3104 and any other device during the same period of time).

[0369] Furthermore, in response to the first Association Request frame (or the first (Re)Association Request frame), AP MLD 3104 may generate a first Association Response frame. The first Association Response frame may be configured to include AP sensing capabilities of one or more APs affiliated with AP MLD 3104. In an embodiment, the first Association Response frame may include first Link Group ID 3110 that may be unique to links (e.g., first sensing link 3110-1, second sensing link 3110-2, and third sensing link 3110-3) between AP MLD 3104 and first non-AP MLD 3106. In an embodiment, one of the AP STAs affiliated with AP MLD 3104 may generate the first Association Response frame.

[0370] Although it is mentioned that AP MLD 3104 may assign first Link Group ID 3110 to the group of three links (e.g., group of three multi -links) between AP MLD 3104 and first non-AP MLD 3106, in other embodiments, AP MLD 3104 may assign another Link Group ID (e.g., Link Group ID 1) to the group of three links between AP MLD 3104 and first non-AP MLD 3106. For example, AP MLD 3104 may assign Link Group ID 1 to the three links between AP MLD 3104 and first non-AP MLD 3106.

[0371] In an embodiment, AP MLD 3104 may be further configured to transmit the first Association Response frame to first non-AP MLD 3106, the first Association Response frame including the first Link Group ID 3110. In an embodiment, the first Association Response frame may be further configured to reassociate the non-AP STA affiliated with first non-AP MLD 3106 and the corresponding AP STA of AP MLD 3104; thus the first Association Response frame may alternatively be referred to as a first (Re)Association Response frame. In other words, AP MLD 3104 may communicate first Link Group ID 3110 and the sensing capabilities of AP MLD 3104 to first non-AP MLD 3106 as part of the first Association Response frame (or the first Reassociation Response frame) generated by AP MLD 3104 on association (or reassociation) with first non-AP MLD 3106. Upon receiving the first Association Response frame, first non-AP MLD 3106 may store the sensing capabilities of AP MLD 3104 in data storage (e.g., Link Group ID storage 538-1 as shown in FIG. 5) or memory. In an embodiment, first Link Group ID 3110 may be carried by a Common Info field in a Basic Multi-Link element carried by the first Association Response frame. Furthermore, the presence of first Link Group ID 3110 in the Common Info field may be signaled by a value in a Presence Bitmap subfield (e.g., enhanced Presence Bitmap subfield 2300) of the Multi-Link Control field in the Basic Multi-Link element as shown in FIG. 23. In an embodiment, after the transmission of the first Association Response frame, AP MLD 3104 may be further configuredto generate a first Sensing Measurement Request frame based on first Link Group ID 3110 and the sensing capabilities of one or more non-AP STAs affiliated with first non-AP MLD 3106. In an embodiment, the first Sensing Measurement Request frame is further based on a sensing goal (e.g., gesture detection, movement detection, or the like). AP MLD 3104 may be further configured to transmit the first Sensing Measurement Request frame to a first non-AP STA (of the non-AP STAs) affiliated with first non-AP MLD 3106 to establish a first sensing measurement session.

[0372] Following the reception of the first Association Response frame by the non-AP STA affiliated with first non-AP MLD 3106, AP MLD 3104 and first non-AP MLD 3106 may have shared common data which corresponds to first Link Group ID 3110. Each of AP MLD 3104 and first non-AP MLD 3106 may store the common data in the data storage (e.g., Link Group ID storage 522 and 538-1, respectively, as shown in FIG. 5) or memory on the corresponding device (e.g., AP MLD 3104 and first non-AP MLD 3106).

[0373] In another embodiment, AP MLD 3104 may be further configured to receive the second Association Request frame from second non-AP MLD 3108 (e.g., the non-AP STA affiliated with second non-AP MLD 3108). In an embodiment, the second Association Request frame may include the MAC address of second non-AP MLD 3108, the MAC addresses of the non-AP STAs affiliated with second non-AP MLD 3108, the MLD ID of second non-AP MLD 3108, the Link IDs associated with the non-AP STAs affiliated with second non-AP MLD 3108, or additional data. Thus, AP MLD 3104 may determine the identity of associations between the AP STAs affiliated with AP MLD 3104 and corresponding non-AP STAs affiliated with second non-AP MLD 3108. In an embodiment, the second Association Request frame (e.g., the additional data in the second Association Request frame) may include the sensing capabilities of one or more non-AP STAs affiliated with second non-AP MLD 3108. Furthermore, AP MLD 3104 may store the sensing capabilities of one or more non-AP STAs affiliated with second non-AP MLD 3108 in data storage (e.g., Link Group ID storage 522 as shown in FIG. 5) or memory.

[0374] In an embodiment, second Link Group ID 3112 may be defined which provides a unique identifier for all AP STA-to-non-AP STA links between AP MLD 3104 and second non-AP MLD 3108. In other words, a second link group may be identified and given a unique Link Group ID (e.g., second Link Group ID 3112) by AP MLD 3104. In an embodiment, second Link Group ID 3112 identifies multi -links between AP MLD 3104 and second non-AP MLD 3108. In additional embodiments, second Link Group ID 3112 identifies multi-links that support sensing between AP MLD 3104 and second non-AP MLD 3108.

[0375] Furthermore, AP MLD 3104 may be configured to assign second Link Group ID 3112 to second non-AP MLD 3108 (or to assign second Link Group ID 3112 to the two links between AP MLD 3104 and second non-AP MLD 3108). AP MLD 3104 may assign (or allocate) second Link Group ID 3112 when second non-AP MLD 3108 associates with AP MLD 3104. In an embodiment, second Link Group ID 3112 may be unique to AP MLD 3104 at a particular time (i.e., the value of second Link Group ID 3112 may refer only to the two links between AP MLD 3104 and second non-AP MLD 3108 during a particular period of time and may not refer to any other links between AP MLD 3104 and any other device during the same period of time).

[0376] Furthermore, in response to the second Association Request frame (or the second (Re)Association Request frame), AP MLD 3104 may generate a second Association Response frame. The second Association Response frame may be configured to include AP sensing capabilities of one or more APs affiliated with AP MLD 3104. In an embodiment, the second Association Response frame may include second Link Group ID 3112 that may be unique to links (e.g., fourth sensing link 3112-1, fifth sensing link 3112-2) between AP MLD 3104 and second non-AP MLD 3108. In an embodiment, one of the AP STAs affiliated with AP MLD 3104 may generate the second Association Response frame.

[0377] Although it is mentioned that AP MLD 3104 may assign second Link Group ID 3112 to the group of two links (e.g., group of two multi-links) between AP MLD 3104 and second non-AP MLD 3108, in various embodiments, AP MLD 3104 may assign another Link Group ID (e.g., Link Group ID 2) to the group of two links between AP MLD 3104 and second non-AP MLD 3108.

[0378] In an embodiment, AP MLD 3104 may be further configured to transmit the second Association Response frame to second non-AP MLD 3108, the second Association Response frame including second Link Group ID 3112. In an embodiment, the second Association Response frame may be further configured to reassociate the non-AP STA affiliated with second non-AP MLD 3108 and the corresponding AP STA, thus the second Association Response frame may alternatively be referred to as a second (Re)Association Response frame. In other words, AP MLD 3104 may communicate second Link Group ID 3112 to second non-AP MLD 3108 as part of the second Association Response frame (or the second Reassociation Request frame) generated by AP MLD 3104 on association (or reassociation) with second non-AP MLD 3108. Upon receiving the second Association Response frame, second non-AP MLD 3108 may store the sensing capabilities of AP MLD 3104 in data storage (e.g., Link Group ID storage 538-1 as shown in FIG. 5) or memory. In an embodiment, second Link Group ID 3112may be carried by a Common Info field in a Basic Multi-Link element carried by the second Association Response frame. Furthermore, the presence of second Link Group ID 3112 in the Common Info field may be signaled by a value in a Presence Bitmap subfield (e.g., enhanced Presence Bitmap subfield 2300) of the Multi-Link Control field in the Basic Multi-Link element as shown in FIG. 23. In an embodiment, after the transmission of the second Association Response frame, AP MLD 3104 may be further configured to generate a second Sensing Measurement Request frame based on second Link Group ID 3112 and the sensing capabilities of one or more non-AP STAs affiliated with second non-AP MLD 3108. In an embodiment, the second Sensing Measurement Request frame is further based on the sensing goal (e.g., gesture detection, movement detection, or the like). AP MLD 3104 may be further configured to transmit a second Sensing Measurement Request frame to a second non-AP STA (of the non-AP STAs) affiliated with second non-AP MLD 3108 to establish a second sensing measurement session.

[0379] Following the reception of the second Association Response frame by the second non-AP STA affiliated with second non-AP MLD 3108, AP MLD 3104 and second non-AP MLD 3108 may have shared common data which corresponds to second Link Group ID 3112. Each of AP MLD 3104 and second non-AP MLD 3108 may store the common data in the data storage (e.g., Link Group ID storage 522 and 538-1, respectively, as shown in FIG. 5) or memory on the corresponding device (e.g., AP MLD 3104 and second non-AP MLD 3108).

[0380] Referring again to FIG. 31, in some embodiments, two Link Group IDs may be defined: first Link Group ID 3110 describes all of the sensing links (e.g., first sensing link 3110-1, second sensing link 3110-2, and third sensing link 3110-3) between AP MLD 3104 and first non-AP MLD 3106, and second Link Group ID 3112 describes all of the sensing links (fourth sensing link 3112-1, fifth sensing link 3112-2) between AP MLD 3104 and second non-AP MLD 3108. In an embodiment, each of first Link Group ID 3110 and second Link Group ID 3112 may be encoded as an integer, and in non-limiting examples, this may be as a 4-bit integer, allowing up to 16 link groups to be formed, as an 8-bit integer, allowing up to 256 link groups to be formed, or as a 12-bit integer, allowing up to 4096 link groups to be formed. Additionally, each of first Link Group ID 3110 and second Link Group ID 3112 may be encoded as integers with a bit length of other than 4, 8, or 12 bits.

[0381] In an embodiment, first Link Group ID 3110 includes n tuples, where each tuple may include {AP MLD ID associated with AP MLD 3104, AP Link ID, non-AP Link ID, non-AP MLD ID associated with first non-AP MLD 3106} and n describes the number of multilink links between AP MLD 3104 and first non-AP MLD 3106. For example, first Link GroupID 3110 may contain three tuples. In another example, n describes the number of multi-link links between AP MLD 3104 and first non-AP MLD 3106 that support sensing (e.g., WLAN sensing). In another embodiment, second Link Group ID 3112 includes n tuples, where each tuple may include {AP MLD ID associated with AP MLD 3104, AP Link ID, non-AP Link ID, non-AP MLD ID associated with second non-AP MLD 3108} and n describes the number of multi-link links between AP MLD 3104 and second non-AP MLD 3108. For example, second Link Group ID 3112 may contain two tuples. In another example, n describes the number of multi-link links between AP MLD 3104 and second non-AP MLD 3108 which support sensing (e.g., WLAN sensing).

[0382] Referring again to FIG. 31, potential sensing links between AP MLD 3104 and first non-AP MLD 3106 may be shown as dashed connections. In an embodiment, connections between the three non-AP STAs of first non-AP MLD 3106 and the three AP STAs of AP MLD 3104 cross the same physical space as each other within sensing space 3102. Similarly, connections between the two non-AP STAs of second non-AP MLD 3108 and the relevant two AP STAs (e.g., any two AP STAs of the three AP STAs available) of AP MLD 3104 may cross the same physical space as each other within sensing space 3102. Each of the overlapping sensing links may support different sensing capabilities. In an embodiment, a sensing measurement session (e.g., the first sensing measurement session and the second sensing measurement session) may be required over each supported sensing link between AP MLD 3104 and each of first non-AP MLD 3106 and second non-AP MLD 3108. In another embodiment, the sensing measurement session may be required over a single sensing link between AP MLD 3104 and each of first non-AP MLD 3106 and second non-AP MLD 3108.

[0383] AP MLD 3104 may be designated as a sensing initiator within a sensing network, such as WLAN sensing network 3100. A sensing application or sensing algorithm, or a sensing controller, on AP MLD 3104 may determine the configuration of sensing links based on stored data. This data includes the Link Group IDs, such as first Link Group ID 3110 and second Link Group ID 3110, as well as the stored sensing capabilities for each link between AP MLD 3104 and non-AP MLDs, including first non-AP MLD 3106 and second non-AP MLD 3108. Specifically, the sensing application or controller may identify which sensing links, including one sensing link between AP MLD 3104 and first non-AP MLD 3106, and one sensing link between AP MLD 3104 and second non-AP MLD 3108, need to be configured. These links, which total two sensing links, may be arranged into one or more sensing measurement sessions, such as the first sensing measurement session and the second sensing measurement session.The sensing application or a sensing controller may also consider a sensing goal when determining which sensing link from a Link Group ID (e.g., first Link Group ID 3110 and second Link Group ID 3112) to select. For example, the sensing goal may be a high-resolution sensing goal such as gesture detection and so the sensing algorithm may favor sensing links that support high-resolution sensing measurements such as sensing links in the 5 GHz or 6 GHz frequency bands. In another embodiment, first non-AP MLD 3106 (or second non-AP MLD 3108) may be the sensing initiator and may implement a sensing application or a sensing controller.

[0384] In an embodiment, AP MLD 3104 acting as the sensing initiator configures sensing measurement sessions (e.g., the first sensing measurement session and the second sensing measurement session) between an identified AP (e.g., an AP STA affiliated with AP MLD 3104) and any non-AP STA according to techniques described by P802.1 Ibf For example, the sensing initiator (e.g., AP MLD 3104) transmits a Sensing Measurement Request frame from the AP to the non-AP STA affiliated with first non-AP MLD 3106 acting as a sensing responder. In reply to the Sensing Measurement Request frame, the non-AP STA may transmit a Sensing Measurement Response frame with a Status Code equal to SUCCESS, indicating the sensing measurement session has been configured successfully.

[0385] Referring again to FIG. 31, the sensing initiator (e.g., AP MLD 3104) may configure two sensing measurement sessions (e.g., the first sensing measurement session and the second sensing measurement session) between an identified AP (e.g., an AP STA) of AP MLD 3104 and non-AP STA of first non-AP MLD 3106, and another identified AP (e.g., an AP STA) of AP MLD 3104 and non-AP STA of second non-AP MLD 3108.

[0386] FIG. 32 depicts an exemplary flowchart 3200 carried out by an AP MLD to share the sensing capabilities of links of the AP MLD, according to some embodiments.

[0387] At step 3202, the AP MLD may transmit a plurality of Beacon frames including information about the multi-link networking device. In an embodiment, the Beacon frame may correspond to an enhanced Beacon frame which includes the availability of the AP STAs. Upon the transmission of the enhanced Beacon frame, a discovery process to identify sensing capabilities is initiated. At step 3204, the AP MLD may receive a Probe Request frame from a first non-AP MLD. In an embodiment, the Probe Request frame may correspond to an enhanced Probe Request frame configured to request the sensing capabilities of the AP STAs affiliated with the AP MLD. At step 3206, the AP MLD may transmit a Probe Response frame including the sensing capabilities of the AP MLD. In an embodiment, the Probe Responseframe may correspond to an enhanced Probe Response frame configured to provide the sensing capabilities of the AP STAs.

[0388] While the above steps shown in FIG. 32 are described in a particular sequence, the steps may occur in variations to the sequence in accordance with various embodiments of the present disclosure. Furthermore, details related to various steps of FIG. 32 which are already covered in the description related to FIG. 1 to FIG. 31 are not discussed again in detail here for the sake of brevity.

[0389] FIG. 33A and FIG. 33B depict an exemplary flowchart 3300 carried out by an AP MLD to perform disambiguation of the MLD identities for the WLAN sensing operation, according to some embodiments.

[0390] In an embodiment, the WLAN sensing system leveraging MLO and the MLDs may be described. Each link of an MLD may support WLAN sensing to a different degree (including not at all) and may offer a range of capabilities. To allow WLAN sensing to take place, these sensing capabilities must be shared between the MLDs so that at least the sensing initiator is aware of the sensing capabilities of potential sensing responders in the WLAN sensing system and so that the sensing initiator may configure suitable sensing measurement sessions to achieve the sensing goal. Where there are multiple links between the sensing devices that may traverse, and so sense, the same channel or sensing space, it may be advantageous for the sensing initiator to understand this so that it may optimize the selection of the sensing sessions based on the requirements of the sensing algorithm. To support these requirements, enhancements to elements, sub-elements, fields, and subfields that support MLO are described in FIG. 18 to FIG. 28 which allow the sharing of sensing capabilities of the MLDs, the AP STAs, and the non-AP STAs. As part of the enhancements, the Link Group ID may be defined that may collectively represent one or more Link IDs so that the sensing initiator may determine an optimum number of sensing measurement sessions to measure the sensing space.

[0391] In a brief overview of an implementation of flowchart 3300, at step 3302, the AP MLD (e.g., AP MLD 3104) may receive a first Association Request frame from the first non-AP MLD (e.g., first non-AP MLD 3106). At step 3304, the AP MLD may assign a first Link Group ID to the first non-AP MLD. At step 3306, the AP MLD may transmit a first Association Response frame to the first non-AP MLD, the first Association Response frame including the first Link Group ID. At step 3308, the AP MLD may receive a second Association Request frame from a second non-AP MLD (e.g., second non-AP MLD 3108). At step 3310, the AP MLD may assign a second Link Group ID to the second non-AP MLD. At step 3312, the AP MLD may transmit a second Association Response frame to the second non-AP MLD, thesecond Association Response frame including the second Link Group ID. At step 3314, the AP MLD may transmit a first Sensing Measurement Request frame to a first non-AP STA affiliated with the first non-AP MLD to establish a first sensing measurement session. At step 3316, the AP MLD may transmit a second Sensing Measurement Request frame to a second non-AP STA affiliated with the second non-AP MLD to establish a second sensing measurement session.

[0392] Step 3302 includes receiving the first Association Request frame from the first non-AP MLD. According to some embodiments, the first Association Request frame may include first sensing capabilities of one or more non-AP stations affiliated with the first non-AP MLD.

[0393] Step 3304 includes assigning the first Link Group ID to the first non-AP MLD. According to some embodiments, the first Link Group ID may provide a unique identifier for all AP STA-to-first non-AP STA links (e.g., sensing links) between the AP MLD and the first non-AP MLD. In an embodiment, the first Link Group ID may identify multi-links between the AP MLD and the first non-AP MLD. Furthermore, the first Link Group ID may identify multi-links that support sensing between the AP MLD and the first non-AP MLD.

[0394] Step 3306 includes transmitting the first Association Response frame to the first non-AP MLD. According to some embodiments, the first Association Response frame may include the AP sensing capabilities of one or more APs affiliated with the AP MLD. Furthermore, the first Association Response frame may include the first Link Group ID assigned to the first non-AP MLD.

[0395] Step 3308 includes receiving the second Association Request frame from the second non-AP MLD. According to some embodiments, the second Association Request frame may include second sensing capabilities of one or more non-AP stations affiliated with the second non-AP MLD.

[0396] Step 3310 includes assigning the second Link Group ID to the second non-AP MLD. According to some embodiments, the second Link Group ID may provide a unique identifier for all AP STA-to-second non-AP STA links (e.g., sensing links) between the AP MLD and the second non-AP MLD.

[0397] Step 3312 includes transmitting the second Association Response frame to the second non-AP MLD. According to some embodiments, the second Association Response frame may include the sensing capabilities of the AP MLD. Furthermore, the second Association Response frame may include the second Link Group ID assigned to the second non-AP MLD.

[0398] Method 3300 further includes generating the first Sensing Measurement Request frame based on the first Link Group ID and generating the second Sensing Measurement Request frame based on the second Link Group ID. In an embodiment, method 3300 includes generating the first Sensing Measurement Request frame based on the first Link Group ID and the first sensing capabilities. Method 3300 includes generating the second Sensing Measurement Request frame based on the second Link Group ID and the second sensing capabilities. In an embodiment, generating the first Sensing Measurement Request frame and / or the second Sensing Measurement Request frame are further based on a sensing goal.

[0399] Step 3314 includes transmitting the first Sensing Measurement Request frame to the first non-AP STA affiliated with the first non-AP MLD to establish the first sensing measurement session. According to some embodiments, the AP MLD may correspond to the sensing initiator by transmitting the first Sensing Measurement Request frame to the first non-AP STA affiliated with the first non-AP MLD that may correspond to the sensing responder. Furthermore, in response to the first Sensing Measurement Request frame, the first non-AP STA affiliated with the first non-AP MLD may transmit a first Sensing Measurement Response frame with a status code equal to SUCCESS, indicating that the first sensing measurement session has been configured successfully.

[0400] Step 3316 includes transmitting the second Sensing Measurement Request frame to the second non-AP STA affiliated with the second non-AP MLD to establish the second sensing measurement session. According to some embodiments, the AP MLD may correspond to the sensing initiator by transmitting the second Sensing Measurement Request frame to the second non-AP STA affiliated with the second non-AP MLD that may correspond to the sensing responder. Furthermore, in response to the second Sensing Measurement Request frame, the second non-AP STA affiliated with the second non-AP MLD may transmit a second Sensing Measurement Response frame with a status code equal to SUCCESS, indicating that the second sensing measurement session has been configured successfully.

[0401] While the above steps shown in FIG. 33A and FIG. 33B are described in a particular sequence, the steps may occur in variations to the sequence in accordance with various embodiments of the present disclosure. Furthermore, details related to various steps of FIG. 33 A and FIG. 33B which are already covered in the description related to FIG. 1 to FIG.32 are not discussed again in detail here for the sake of brevity.

[0402] In operation, the WLAN network / WLAN sensing network may be implemented by the BSS comprising the AP device that supports multi-link functionality (e.g., multi-link device AP or AP MLD 3104 in FIG. 31) and one or more non-AP devices that also support multi-linkfunctionality (e.g., first non-AP MLD 3106 and first non-AP MLD 3106). The AP MLD includes two or more affiliated AP ST As and each of the non-AP MLDs includes two or more affiliated non-AP STAs. The WLAN network may be used for WLAN sensing. When the WLAN network supports MLO, then there may be more than one link established between the AP MLD and each of the non-AP MLDs. Each link is established between the AP MLD (implemented by AP MLD 3104) and the STA (implemented by the non-AP MLD). In an embodiment, where the WLAN network may be a WLAN sensing network (e.g., WLAN sensing network 3100) then each of these links may be used for sensing transmissions and for making sensing measurements. One or more links of the multiple multi-links that may be available between the AP MLD and each of the non-AP MLDs may support WLAN sensing and this support may be defined by properties and capabilities which may be described broadly as the sensing capabilities. Each link between the AP MLD and each of the non-AP MLDs may operate at a different frequency, in a different frequency band, and / or with a different channel bandwidth, thus each link may exhibit different sensing capabilities. In an embodiment, WLAN sensing is achieved by the transmission of a sensing transmission in a channel between a sensing transmitter and a sensing receiver, and by the measurement of properties of the channel based on properties of the sensing transmission as received by the sensing receiver. Furthermore, the sensing application (or sensing algorithm) may be implemented by a device in the WLAN network or by another device that may learn the sensing capabilities of each link and the sensing capabilities of all sensing devices in the sensing network.

[0403] From the learned sensing capabilities, the sensing application may determine sensing transmitters, sensing receivers, and sensing measurements that fulfill a sensing goal. With this information, the sensing application may cause sensing transmissions to be made by sensing transmitters and sensing measurements to be made by sensing receivers. This process may be achieved by identifying the sensing initiator and sensing responders and initiating one or more sensing measurement sessions. The initial step in this process involves the sensing devices within the sensing network sharing their sensing capabilities. Furthermore, where a sensing device is also an MLD, then there is more than one sensing link and the sensing capabilities of each sensing link may be shared.

[0404] The discovery process may be initiated where the AP MLD may share its sensing capabilities with the non-AP MLD. During the discovery process, each AP STA affiliated with the AP MLD may generate a Beacon frame that enables listening non-AP STAs to learn about BSS parameters and the AP STA that implements the BSS. The Beacon frame may also provide basic information about other AP STAs affiliated with the AP MLD. The Beacon frame mayindicate that the transmitting AP and other AP STAs affiliated with the AP MLD may support WLAN sensing. Furthermore, the non-AP MLD may transmit a Probe Request frame to the AP MLD. A suitably configured Probe Request frame may allow the non-AP MLD to request more detailed information on the AP MLD’s support for WLAN sensing. The Probe Request frame may be sent to any AP MLD irrespective of whether a Beacon frame has been received and processed.

[0405] Furthermore, in response to the Probe Request frame, the AP MLD may send (e.g., transmit) the Probe Response frame which includes information on the WLAN sensing capabilities of the AP MLD, including the WLAN sensing capabilities of each of the APs affiliated with the AP MLD. After the discovery process, the non-AP MLD may have learned about the sensing capabilities of the AP MLD and may associate with the AP MLD to exchange data and perform WLAN sensing. As part of the association process, the non-AP MLD may share its sensing capabilities (e.g., its WLAN sensing capabilities) with the AP MLD.

[0406] Furthermore, a single non-AP MLD non-AP STA (e.g., a non-AP STA associated with the non-AP MLD) and a single AP MLD AP STA (e.g., an AP STA associated with the MLD) are selected by the non-AP MLD to perform the (re)association process and the non-AP MLD non-AP STA and the AP MLD AP STA authenticate each other by sharing authentication messages. The non-AP MLD non-AP STA may transmit a (Re)Association Request frame to the AP MLD AP STA. A suitably configured (Re)Association Request frame may allow the non-AP MLD to share information on the non-AP MLD’s support for WLAN sensing. The (Re)Association frame may be sent to any AP MLD irrespective of whether a Beacon frame or a Probe Response frame has been received and processed. In response to the (Re)Association Request frame, the AP MLD AP STA may transmit a (Re)Association Response frame to the non-AP MLD non-AP STA. The (Re)Association Response frame may include information on the WLAN sensing capabilities of the AP MLD, including the WLAN sensing capabilities of each of the APs affiliated with the AP MLD. Furthermore, the 4-way handshake may be performed to complete the association process. The 4-way handshake may be as described by P802.11REVme.

[0407] In an embodiment, sensing transmissions may be configured and made without the sensing transmitter and the sensing receiver being associated in the BSS by means of the mechanism of sensing with unassociated STAs. Furthermore, sensing with unassociated MLDs may be an extension to this mechanism where sensing is carried out between MLDs that are unassociated. To allow the configuration of sensing with unassociated MLDs, both the AP MLD and the non-AP MLD may be required to understand each other’s sensing capabilitieswithout being associated with each other. To support sensing with unassociated MLDs, the Probe Request frame may be enhanced to include the sensing capabilities of the non-AP MLD (including all affiliated non-AP STAs) which transmits the Probe Request frame.

[0408] The WLAN sensing network comprises multiple sensing devices which are MLDs such that there may be multiple sensing links between each of the multiple sensing devices. Since these sensing links may originate from and terminate at the same physical devices, it can be inferred that these links traverse the same physical space within the sensing environment. Each of these overlapping sensing links may support different sensing capabilities and thus a sensing measurement session may be required over each supported link. In an embodiment, it may be sufficient to configure and make a sensing transmission over a single link between the AP MLD and the non-AP MLD.

[0409] In an embodiment, the Link Group ID may provide a unique identifier for all AP STA-to-non-AP STA links between an AP MLD and a non-AP MLD. The AP MLD may identify a link group and further provide a unique Link Group ID to the corresponding link group. The AP MLD may assign the Link Group ID when a non-AP MLD is associated with the AP MLD. Furthermore, the AP MLD may communicate the Link Group ID to the non-AP MLD. Following the processes described above, all the MLDs in the WLAN sensing network may have a data store including the sensing capabilities of all MLDs in the WLAN sensing network. The data store may further include which links of the available multi-links share a common sensing device. With this information, one or more sensing measurement sessions may be configured.

[0410] In an embodiment, an MLD may be designated as the sensing initiator for the WLAN sensing network. The sensing application or algorithm, or the sensing controller on the MLD, may then utilize the stored Link Group ID and the stored sensing capabilities for each link between the AP MLD and the non-AP MLD. Based on this information, the application or controller may determine which specific sensing link between the AP MLD and the non-AP MLD is to be configured for a sensing measurement session. In an embodiment, the sensing application or a sensing controller may also consider a sensing goal when determining which sensing link from the Link Group ID to select.

[0411] Furthermore, the MLD acting as the sensing initiator may configure the sensing measurement session between the identified AP and the non-AP STA according to techniques described by P802.11bf. For example, the sensing initiator may transmit a Sensing Measurement Request frame from the AP STA to the non-AP STA affiliated with the non-AP MLD acting as a sensing responder. Furthermore, the non-AP STA may transmit a SensingMeasurement Response frame in reply to the Sensing Measurement Request frame. The Sensing Measurement Response frame may include a Status Code equal to SUCCESS, indicating the sensing measurement session has been configured successfully.

[0412] The present disclosure has multiple advantages. In an embodiment, the AP MLD has multiple links established with each of the first non-AP MLD and the second non-AP MLD. Furthermore, the AP MLD may share the sensing capabilities associated with one or more AP STAs affiliated with the AP MLD based on at least one of the Beacon frames (e.g., the enhanced Beacon frame) and the Probe Response frame (e.g., the enhanced Probe Response frame). Furthermore, the AP MLD may receive the sensing capabilities associated with one or more non-AP STAs affiliated with each of the first non-AP MLD and the second non-AP MLD. Additionally, the AP MLD may further assign a first Link Group ID to multiple links between the AP MLD and the first non-AP MLD. Furthermore, the AP MLD may assign a second Link Group ID to multiple links between the AP MLD and the second non-AP MLD. Thus, the AP MLD may identify the multiple links between the AP MLD and each of the first non-AP MLD and the second non-AP MLD based on the first Link Group ID and the second Link Group ID, respectively. In an embodiment, the AP MLD may determine that one or more non-AP STAs may be affiliated with the first non-AP MLD and the second non-AP MLD based on the first Link Group ID and the second Link Group ID, respectively. Furthermore, each link of the multiple links with a single Link Group ID may cross the same physical space and may have different sensing capabilities. Thus, the AP MLD may select a first link (one or more links) with the first Link Group ID to initiate sensing (e.g., WLAN sensing) based on a specific sensing goal.

[0413] Embodiment 1 is a method for Wi-Fi sensing carried out by an access point multilink device (AP MLD) including a transmitting antenna, a receiving antenna, a plurality of radios, and at least one processor configured to execute instructions, the method comprising: receiving a first Association Request frame from a first non-AP multi-link device (MLD); assigning a first Link Group ID to the first non-AP MLD; transmitting a first Association Response frame to the first non-AP MLD, the first Association Response frame including the first Link Group ID; receiving a second Association Request frame from a second non-AP MLD; assigning a second Link Group ID to the second non-AP MLD; transmitting a second Association Response frame to the second non-AP MLD, the second Association Response frame including the second Link Group ID; transmitting a first Sensing Measurement Request frame to a first station affiliated with the first non-AP MLD to establish a first sensing measurement session; and transmitting a second Sensing Measurement Request frame to asecond station affiliated with the second non-AP MLD to establish a second sensing measurement session.

[0414] Embodiment 2 is the method of embodiment 1, wherein the first Association Request frame includes first sensing capabilities of one or more non-AP stations affiliated with the first non-AP MLD.

[0415] Embodiment 3 is the method of embodiment 1 or 2, wherein the first Link Group ID identifies multi-links between the AP MLD and the first non-AP MLD.

[0416] Embodiment 4 is the method of embodiment 1 or 2, wherein the first Link Group ID identifies multi-links that support sensing between the AP MLD and the first non-AP MLD.

[0417] Embodiment 5 is the method of any one of embodiments 1 to 4, further comprising generating the first Sensing Measurement Request frame based on the first Link Group ID and generating the second Sensing Measurement Request frame based on the second Link Group ID.

[0418] Embodiment 6 is the method of any one of embodiments 1 to 5, wherein the first Association Response frame includes first AP sensing capabilities of one or more APs affiliated with the AP MLD.

[0419] Embodiment 7 is the method of any one of embodiments 1 to 6, wherein the first Association Request frame includes first sensing capabilities of one or more non-AP stations affiliated with the first non-AP MLD and the second Association Request frame includes second sensing capabilities of one or more non-AP stations affiliated with the second non-AP MLD, the method further comprising: generating the first Sensing Measurement Request frame based on the first Link Group ID and the first sensing capabilities and generating the second Sensing Measurement Request frame based on the second Link Group ID and the second sensing capabilities.

[0420] Embodiment 8 is the method of embodiment 7, wherein generating the first Sensing Measurement Request frame is further based on a sensing goal.

[0421] Embodiment 9 is the method of any one of embodiments 1 to 8, further comprising: transmitting a plurality of Beacon frames by the plurality of radios including information about the AP MLD; receiving a Probe Request frame from the first non-AP MLD; and transmitting a Probe Response frame including sensing capabilities of the AP MLD.

[0422] Embodiment 10 is a system for Wi-Fi sensing carried out by an access point multilink device (AP MLD) including a transmitting antenna, a receiving antenna, a plurality of radios, and at least one processor configured to execute instructions for: receiving a first Association Request frame from a first non-AP multi-link device (MLD); assigning a first LinkGroup ID to the first non-AP MLD; transmitting a first Association Response frame to the first non-AP MLD, the first association response frame including the first Link Group ID; receiving a second Association Request frame from a second non-AP MLD; assigning a second Link Group ID to the second non-AP MLD; transmitting a second Association Response frame to the second non-AP MLD, the second Association Response frame including the second Link Group ID; transmitting a first Sensing Measurement Request frame to a first station affiliated with the first non-AP MLD to establish a first sensing measurement session; and transmitting a second Sensing Measurement Request frame to a second station affiliated with the second non-AP MLD to establish a second sensing measurement session.

[0423] Embodiment 11 is the system of embodiment 10, wherein the first Association Request frame includes first sensing capabilities of one or more non-AP stations affiliated with the first non-AP MLD.

[0424] Embodiment 12 is the system of embodiment 10 or 11, wherein the first Link Group ID identifies multi-links between the AP MLD and the first non-AP MLD.

[0425] Embodiment 13 is the system of embodiment 10 or 11, wherein the first Link Group ID identifies multi-links that support sensing between the AP MLD and the first non-AP MLD.

[0426] Embodiment 14 is the system of any one of embodiments 10 to 13, wherein the at least one processor further includes instructions for generating the first Sensing Measurement Request frame based on the first Link Group ID and generating the second Sensing Measurement Request frame based on the second Link Group ID.

[0427] Embodiment 15 is the system of any one of embodiments 10 to 14, wherein the first Association Response frame includes first AP sensing capabilities of one or more APs affiliated with the AP MLD.

[0428] Embodiment 16 is the system of any one of embodiments 10 to 15, wherein the first Association Request frame includes first sensing capabilities of one or more non-AP stations affiliated with the first non-AP MLD and the second Association Request frame includes second sensing capabilities of one or more non-AP stations affiliated with the second non-AP MLD, and wherein the at least one processor further includes instructions for: generating the first Sensing Measurement Request frame based on the first Link Group ID and the first sensing capabilities and generating the second Sensing Measurement Request frame based on the second Link Group ID and the second sensing capabilities.

[0429] Embodiment 17 is the system of embodiment 16, wherein generating the first Sensing Measurement Request frame is further based on a sensing goal.

[0430] Embodiment 18 is the system of any one of embodiments 10 to 17, wherein the at least one processor further includes instructions for: transmitting a plurality of Beacon frames by the plurality of radios including information about the AP MLD; receiving a Probe Request frame from the first non-AP MLD; and transmitting a Probe Response frame including sensing capabilities of the AP MLD.

[0431] While various embodiments of the methods and systems have been described, these embodiments are illustrative and in no way limit the scope of the described methods or systems. Those having skill in the relevant art can effect changes to the form and details of the described methods and systems without departing from the broadest scope of the described methods and systems. Thus, the scope of the methods and systems described herein should not be limited by any of the illustrative embodiments and should be defined in accordance with the accompanying claims and their equivalents.

Claims

We claim1. A method for Wi-Fi sensing carried out by an access point multi-link device (AP MLD) including a transmitting antenna, a receiving antenna, a plurality of radios, and at least one processor configured to execute instructions, the method comprising:receiving a first Association Request frame from a first non-AP multi-link device (MLD);assigning a first Link Group ID to the first non-AP MLD;transmitting a first Association Response frame to the first non-AP MLD, the first Association Response frame including the first Link Group ID;receiving a second Association Request frame from a second non-AP MLD; assigning a second Link Group ID to the second non-AP MLD;transmitting a second Association Response frame to the second non-AP MLD, the second Association Response frame including the second Link Group ID;transmitting a first Sensing Measurement Request frame to a first station affiliated with the first non-AP MLD to establish a first sensing measurement session; andtransmitting a second Sensing Measurement Request frame to a second station affiliated with the second non-AP MLD to establish a second sensing measurement session.

2. The method of claim 1, wherein the first Association Request frame includes first sensing capabilities of one or more non-AP stations affiliated with the first non-AP MLD.

3. The method of claim 1, wherein the first Link Group ID identifies multi-links between the AP MLD and the first non-AP MLD.

4. The method of claim 1, wherein the first Link Group ID identifies multi -links that support sensing between the AP MLD and the first non-AP MLD.

5. The method of claim 1, further comprising generating the first Sensing Measurement Request frame based on the first Link Group ID and generating the second Sensing Measurement Request frame based on the second Link Group ID.

6. The method of claim 1, wherein the first Association Response frame includes first AP sensing capabilities of one or more APs affiliated with the AP MLD.

7. The method of claim 1, wherein the first Association Request frame includes first sensing capabilities of one or more non-AP stations affiliated with the first non-AP MLD and the second Association Request frame includes second sensing capabilities of one or more non-AP stations affiliated with the second non-AP MLD, the method further comprising:generating the first Sensing Measurement Request frame based on the first Link Group ID and the first sensing capabilities and generating the second Sensing Measurement Request frame based on the second Link Group ID and the second sensing capabilities.

8. The method of claim 7, wherein generating the first Sensing Measurement Request frame is further based on a sensing goal.

9. The method of claim 1, further comprising:transmitting a plurality of Beacon frames by the plurality of radios including information about the AP MLD;receiving a Probe Request frame from the first non-AP MLD; andtransmitting a Probe Response frame including sensing capabilities of the AP MLD.

10. A system for Wi-Fi sensing carried out by an access point multi -link device (AP MLD) including a transmitting antenna, a receiving antenna, a plurality of radios, and at least one processor configured to execute instructions for:receiving a first Association Request frame from a first non-AP multi-link device (MLD);assigning a first Link Group ID to the first non-AP MLD;transmitting a first Association Response frame to the first non-AP MLD, the first association response frame including the first Link Group ID;receiving a second Association Request frame from a second non-AP MLD; assigning a second Link Group ID to the second non-AP MLD;transmitting a second Association Response frame to the second non-AP MLD, the second Association Response frame including the second Link Group ID;transmitting a first Sensing Measurement Request frame to a first station affiliated with the first non-AP MLD to establish a first sensing measurement session; andtransmitting a second Sensing Measurement Request frame to a second station affiliated with the second non-AP MLD to establish a second sensing measurement session.

11. The system of claim 10, wherein the first Association Request frame includes first sensing capabilities of one or more non-AP stations affiliated with the first non-AP MLD.

12. The system of claim 10, wherein the first Link Group ID identifies multi-links between the AP MLD and the first non-AP MLD.

13. The system of claim 10, wherein the first Link Group ID identifies multi-links that support sensing between the AP MLD and the first non-AP MLD.

14. The system of claim 10, wherein the at least one processor further includes instructions for generating the first Sensing Measurement Request frame based on the first Link Group ID and generating the second Sensing Measurement Request frame based on the second Link Group ID.

15. The system of claim 10, wherein the first Association Response frame includes first AP sensing capabilities of one or more APs affiliated with the AP MLD.

16. The system of claim 10, wherein the first Association Request frame includes first sensing capabilities of one or more non-AP stations affiliated with the first non-AP MLD and the second Association Request frame includes second sensing capabilities of one or more non-AP stations affiliated with the second non-AP MLD, and wherein the at least one processor further includes instructions for:generating the first Sensing Measurement Request frame based on the first Link Group ID and the first sensing capabilities and generating the second Sensing Measurement Request frame based on the second Link Group ID and the second sensing capabilities.

17. The system of claim 16, wherein generating the first Sensing Measurement Request frame is further based on a sensing goal.

18. The system of claim 10, wherein the at least one processor further includes instructions for:transmitting a plurality of Beacon frames by the plurality of radios including information about the AP MLD;receiving a Probe Request frame from the first non-AP MLD; andtransmitting a Probe Response frame including sensing capabilities of the AP MLD.

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