Method and apparatus for performing sensing in a wireless LAN system

Abstract

A method and apparatus for performing sensing in a wireless LAN system are proposed. Specifically, a first STA broadcasts a sensing request frame. The first STA receives a first sensing response frame from a second STA and a second sensing response frame from a third STA. The sensing request frame includes STA identifier information and RU allocation information. The STA identifier information includes identifiers of the second and third STAs. The RU allocation information includes information on a first RU allocated to the second STA and information on a second RU allocated to the third STA. The first sensing response frame is received via the first RU. The second sensing response frame is received via the second RU.

Description

[Technical Field]

[0001] The present specification relates to a technique for performing sensing in a wireless LAN system, and more particularly to a method and apparatus for negotiating STAs that will participate in sensing and parameters used in sensing to perform a sensing procedure. [Background technology]

[0002] WLAN (wireless local area network) has been improved in various ways. For example, IEEE802.11bf wireless LAN sensing is the first standard to combine communications and radar technologies. Demand for unlicensed frequencies is rapidly increasing in everyday life and industry, but new frequency supply is limited. Therefore, the development of communication and radar integration technology is a very favorable direction for increasing frequency utilization efficiency. Existing sensing technologies include those that use WLAN signals to detect movement behind walls and radar technologies that use frequency-modulated continuous wave (FMCW) signals in the 70 GHz band to detect movement inside vehicles. The IEEE802.11bf standardization is significant in that it will take sensing performance to the next level. In particular, with the increasing emphasis on privacy protection in modern society, there is a growing expectation for the development of WLAN sensing technology, which, unlike CCTV, offers greater legal freedom in addressing privacy infringement issues.

[0003] Meanwhile, the overall radar market across sectors including automobiles, defense, industry, and lifestyle is predicted to grow at a CAGR of approximately 5% until 2025, with lifestyle sensors expected to see particularly rapid growth of up to 70%. WLAN sensing technology can be applied to a wide range of real-life applications, including motion detection, respiration monitoring, positioning / tracking, fall detection, in-vehicle infant detection, appearance / proximity recognition, personal identification, body movement recognition, and behavior recognition, and is expected to promote the growth of related new businesses and contribute to improving corporate competitiveness. Summary of the Invention [Problem to be solved by the invention]

[0004] This specification proposes a method and apparatus for performing sensing in a wireless LAN system. [Means for solving the problem]

[0005] An example herein proposes a method for performing sensing.

[0006] This embodiment can be implemented in a network environment supporting a next-generation wireless LAN system (IEEE 802.11bf), which is an improved version of the 802.11ad and 802.11ay systems and can achieve backward compatibility with the 802.11ad and 802.11ay systems.

[0007] This embodiment is performed in a first STA, which can serve as a sensing initiator, and the second and third STAs in this embodiment can serve as sensing responders.

[0008] This embodiment proposes a method for determining STAs that will participate in sensing in a wireless LAN system, negotiating parameters to be used for sensing, and executing a sensing procedure based on the negotiated parameters. In particular, this embodiment proposes a method for role negotiation in the negotiation step, parameter negotiation, and parameter change in the sensing step.

[0009] A first STA (station) broadcasts a sensing request frame.

[0010] The first STA receives a first sensing response frame from a second STA and receives a second sensing response frame from a third STA.

[0011] The sensing request frame includes STA identifier information and RU (Resource Unit) allocation information. The STA identifier information includes identifiers of the second and third STAs. The RU allocation information includes information on a first RU allocated to the second STA and information on a second RU allocated to the third STA.

[0012] The first sensing response frame is received via the first RU, and the second sensing response frame is received via the second RU. That is, responses to the sensing request frame can be received (simultaneously) by the second and third STAs based on Orthogonal Frequency Division Multiple Access (OFDMA). The sensing request frame can be a (newly defined) trigger frame. If the STA identifier information does not include the identifier of a fourth STA, the first STA does not receive the third sensing response frame from the fourth STA.

[0013] That is, in this embodiment, the sensing request frame indicates the identifier (ID) of the STA receiving the sensing response frame and RU allocation information, and the STA corresponding to the STA identifier can receive the sensing request frame and transmit the sensing response frame through the assigned RU after SIFS. [Effects of the Invention]

[0014] According to the embodiments proposed in this specification, various sensing measurement and sensing reporting scenarios can be defined through STA setup and negotiation procedures for WLAN sensing support, and accordingly, the movement and changes of a user or object can be detected by performing sensing operations efficiently and smoothly. [Brief explanation of the drawings]

[0015] [Figure 1]1 illustrates an example of a transmitting device and / or a receiving device of the present specification. [Figure 2] An example of a wireless LAN sensing scenario using multiple sensing transmitters is shown below. [Figure 3] An example of a wireless LAN sensing scenario using multiple sensing receivers is shown below. [Figure 4] An example of a wireless LAN sensing procedure is shown. [Figure 5] This is an example of classification of wireless LAN sensing. [Figure 6] This demonstrates indoor positioning using CSI-based wireless LAN sensing. [Figure 7] This is an example of a wireless LAN sensing device. [Figure 8] 1 illustrates a modified example of the transmitting device and / or receiving device of the present specification. [Figure 9] An example of WLAN sensing is shown below. [Figure 10] 1 is a flow chart showing a procedure for WLAN sensing. [Figure 11] An example of a sensing action frame is shown below. [Figure 12] An example of a Basic SENS Request / Response frame exchange is shown below. [Figure 13] An embodiment 1) in which a SENS Request is sent independently to each SENS STA within one BSS is shown. [Figure 14] An embodiment 1-2) in which a timer is operated and a SENS Request is sent until the timer expires is shown. [Figure 15] An embodiment 1-3) for informing other STAs that no more SENS Request frames will be transmitted will be shown. [Figure 16] An embodiment 1-3) in which a SENS Completion frame is transmitted to notify that the negotiation has been completed will be described. [Figure 17]An example of applying a timeout that takes into account failure cases for the Intended SENS RPSTA is shown below. [Figure 18] An example of a Broadcast SENS Request frame including timer information and negotiation completion information is shown below. [Figure 19] An example of broadcasting a SENS Request to multiple SENS STAs is shown below. [Figure 20] An example 2-2) is shown in which the STA ID for which a response is desired is specified when a SENS request is sent. [Figure 21] Example 2-2) shows an example of sequentially responding to SIFS intervals. [Figure 22] In Example 2-2), an example is shown in which a failure case is taken into consideration using a method that uses SIFS. [Figure 23] Example 2-2) shows an example of an OFDMA response at SIFS intervals. [Figure 24] An example of setting a timer for receiving a response from the SENS STA is shown below. [Figure 25] Examples 2-4) are shown in which a new SENS completion frame is sent or an explicit indicator to complete the negotiation is included in the SENS Request frame. [Figure 26] 1-1) Provide an example of role negotiation based on the method. [Figure 27] 1-1) Provide an example of role negotiation based on the method. [Figure 28] This section shows how to specify a role using methods A, B, and C. [Figure 29] 1-3) Show an example of role negotiation based on the method. [Figure 30] 2-1) Show an example of role negotiation based on the method. [Figure 31]This section shows how to specify a role using methods A, B, and C. [Figure 32] When sensing-related frame exchange is not performed during T_sens, an embodiment 2-1) of tearing down negotiation is shown. [Figure 33] An example 2-2) in which sensing is performed during T_sens and the sensing phase is then terminated will be shown. [Figure 34] STA1, STA2, and STA3 form a sensing group, and when STA1 transmits the group ID, STA2 and STA3 join the sensing together (Example 6) is shown. [Figure 35] An example is shown in which, of the 80 MHz, primary 40 MHz is assigned to STA2 and secondary 40 MHz is assigned to STA3, and sensing signals are transmitted and received. [Figure 36] An example of a sensing procedure in which a Session ID is used is shown below. [Figure 37] An example in which the SENS initiation frame is transmitted multiple times is shown below. [Figure 38] An example of transmitting a SENS initiation frame for each sensing session is shown below. [Figure 39] An example of the negotiation phase and reduced negotiation phase is shown below. [Figure 40] Here are other examples of the negotiation phase and reduced negotiation phase: [Figure 41] Here is an example of dynamic changes to negotiated roles and parameters: [Figure 42] This is an example of a control field for a Dynamic Parameter. [Figure 43]Here is an example of dynamic changes to roles and parameters negotiated using the reduced SENS initiation frame: [Figure 44] Here is an example of dynamic changes to the roles and parameters negotiated during the re-negotiation phase using the reduced SENS Request / Response frame. [Figure 45] An example of changing the role in embodiment 2) is shown below. [Figure 46] An example of changing the bandwidth measured in embodiment 2) will be described below. [Figure 47] This is an example of changing STA information in the second embodiment. [Figure 48] 10 is a flowchart showing a procedure in which a sensing initiator executes sensing according to the present embodiment. [Figure 49] 10 is a flowchart showing a procedure for a sensing responder to perform sensing according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0016] As used herein, "A or B" can mean "only A," "only B," or "both A and B." Also, as used herein, "A or B" can be interpreted as "A and / or B." For example, as used herein, "A, B or C" can mean "only A," "only B," "only C," or "any combination of A, B, and C."

[0017] As used herein, a slash ( / ) or a comma can mean "and / or." For example, "A / B" can mean "A and / or B." Thus, "A / B" can mean "only A," "only B," or "both A and B." For example, "A, B, C" can mean "A, B, or C."

[0018] As used herein, "at least one of A and B" can mean "only A," "only B," or "both A and B." Additionally, as used herein, the expressions "at least one of A or B" and "at least one of A and / or B" can be interpreted in the same way as "at least one of A and B."

[0019] Furthermore, in this specification, "at least one of A, B and C" can mean "only A," "only B," "only C," or "any combination of A, B and C." Furthermore, "at least one of A, B or C" or "at least one of A, B and / or C" can mean "at least one of A, B and C."

[0020] In this specification, technical features individually described in one drawing may be embodied individually or simultaneously.

[0021] The following example of the present specification may be applied to various wireless communication systems. For example, the following example of the present specification may be applied to a wireless local area network (WLAN) system. For example, the present specification may be applied to the IEEE 802.11ad standard or the IEEE 802.11ay standard. The present specification may also be applied to the newly proposed WLAN sensing standard or the IEEE 802.11bf standard.

[0022] In the following, in order to explain the technical features of this specification, the technical features to which this specification is applied will be explained.

[0023] FIG. 1 shows an example of a transmitting device and / or a receiving device of this specification.

[0024] The example of Figure 1 can implement various technical features described below. Figure 1 relates to at least one STA (station). For example, the STAs (110, 120) herein may be referred to by various names such as a mobile terminal, wireless device, wireless transmit / receive unit (WTRU), user equipment (UE), mobile station (MS), mobile subscriber unit, or simply user. The STAs (110, 120) herein may be referred to by various names such as a network, base station, Node-B, access point (AP), repeater, router, relay, etc. The STAs (110, 120) herein may be referred to by various names such as a receiving device, transmitting device, receiving STA, transmitting STA, receiving device, transmitting device, etc.

[0025] For example, the STAs (110, 120) can perform either an AP (Access Point) role or a non-AP role. That is, the STAs (110, 120) in this specification can perform the functions of an AP and / or a non-AP. In this specification, an AP can also be referred to as an AP STA.

[0026] The STAs (110, 120) of this specification can support various communication standards other than the IEEE 802.11 standard. For example, they can support communication standards related to the 3GPP (registered trademark) standard (e.g., LTE, LTE-A, 5GNR standard). The STAs of this specification can be implemented in various devices such as mobile phones, vehicles, and personal computers. The STAs of this specification can support communication for various communication services such as voice calls, video calls, data communications, and self-driving and autonomous driving.

[0027] As used herein, the STAs (110, 120) may include a medium access control (MAC) and physical layer interface to the wireless medium as defined by the IEEE 802.11 standard.

[0028] The STAs (110, 120) will be described below based on FIG. 1(a).

[0029] The first STA 110 includes a processor 111, a memory 112, and a transceiver 113. The illustrated processor, memory, and transceiver may each be implemented as a separate chip, or at least two or more blocks / functions may be implemented on a single chip.

[0030] The transceiver (113) of the first STA performs signal transmission and reception operations, specifically, it can transmit and receive IEEE 802.11 packets (for example, IEEE 802.11a / b / g / n / ac / ax / be, etc.).

[0031] For example, the first STA (110) can perform the intended operations of the AP. For example, the AP's processor (111) can receive signals via the transceiver (113), process the received signals, generate transmit signals, and perform control for signal transmission. The AP's memory (112) can store signals received via the transceiver (113) (i.e., received signals) and can store signals to be transmitted via the transceiver (i.e., transmit signals).

[0032] For example, the second STA (120) can perform the intended operations of a non-AP STA. For example, the non-AP transceiver (123) can transmit and receive signals. Specifically, it can transmit and receive IEEE 802.11 packets (e.g., IEEE 802.11a / b / g / n / ac / ax / be, etc.).

[0033] For example, the processor (121) of the non-AP STA can receive signals via the transceiver (123), process the received signals, generate transmission signals, and perform control for signal transmission. The memory (122) of the non-AP STA can store signals received via the transceiver (123) (i.e., received signals) and can store signals to be transmitted via the transceiver (i.e., transmitted signals).

[0034] For example, in the following specification, the operation of the device designated as AP is performed in the first STA (110) or the second STA (120). For example, if the first STA (110) is an AP, the operation of the device designated as AP is controlled by a processor (111) of the first STA (110), and related signals are transmitted or received via a transceiver (113) controlled by the processor (111) of the first STA (110). Control information related to the operation of the AP and transmitted / received signals of the AP are stored in a memory (112) of the first STA (110). If the second STA (110) is an AP, the operation of the device designated as AP is controlled by a processor (121) of the second STA (120), and related signals are transmitted or received via a transceiver (123) controlled by the processor (121) of the second STA (120). Control information related to the operation of the AP and transmitted / received signals of the AP are stored in a memory (122) of the second STA (110).

[0035] For example, in the following specification, the operation of a device designated as non-AP (or User-STA) is performed in the first STA (110) or the second STA (120). For example, if the second STA (120) is a non-AP, the operation of the device designated as non-AP is controlled by the processor (121) of the second STA (120), and related signals are transmitted or received via the transceiver (123) controlled by the processor (121) of the second STA (120). In addition, control information related to the operation of the non-AP and AP transmission / reception signals are stored in the memory (122) of the second STA (120). For example, if the first STA (110) is a non-AP, the operation of the device designated as non-AP is controlled by the processor (111) of the first STA (110), and related signals are transmitted or received via the transceiver (113) controlled by the processor (111) of the first STA (120). In addition, control information related to the operation of the non-AP and transmission / reception signals of the AP are stored in the memory (112) of the first STA (110).

[0036] In the following specification, devices referred to as a (transmitting / receiving) STA, first STA, second STA, STA1, STA2, AP, first AP, second AP, AP1, AP2, (transmitting / receiving) terminal, (transmitting / receiving) device, (transmitting / receiving) apparatus, network, etc. refer to the STAs (110, 120) in Figure 1. For example, devices referred to as a (transmitting / receiving) STA, first STA, second STA, STA1, STA2, AP, first AP, second AP, AP1, AP2, (transmitting / receiving) terminal, (transmitting / receiving) device, (transmitting / receiving) apparatus, network, etc. without specific reference numerals also refer to the STAs (110, 120) in Figure 1. For example, in the following example, operations by various STAs to transmit and receive signals (e.g., PPPDUs) may be performed in transceivers (113, 123) in Figure 1. Also, in the following example, operations in which various STAs generate transmission / reception signals or perform data processing or calculations in advance for transmission / reception signals may be executed by the processors (111, 121) in Fig. 1. For example, examples of operations in which various STAs generate transmission / reception signals or perform data processing or calculations in advance for transmission / reception signals may include: 1) operations of determining / acquiring / configuring / calculating / decoding / encoding bit information of subfields (SIG, STF, LTF, Data) included in a PPDU, 2) operations of determining / configuring / acquiring time resources and frequency resources (e.g., subcarrier resources) used for the subfields (SIG, STF, LTF, Data) included in a PPDU, 3) operations of determining / configuring / acquiring specific sequences (e.g., pilot sequences, STF / LTF sequences, extra sequences applied to SIG) used for the subfields (SIG, STF, LTF, Data) included in a PPDU, 4) power control operations and / or power saving operations applied to the STAs, and 5) operations related to determining / acquiring / configuring / calculating / decoding / encoding an ACK signal.Also, in the following example, various information (e.g., information related to fields / subfields / control fields / parameters / power, etc.) used by various STAs to determine / acquire / configure / calculate / decode / encode transmitted / received signals is stored in memories (112, 122) of FIG. 1.

[0037] The device / STA of Fig. 1(a) described above is modified as shown in Fig. 1(b). The STAs (110, 120) of this specification will be described based on Fig. 1(b) below.

[0038] For example, the transceivers (113, 123) shown in FIG. 1(b) may perform the same functions as the transceivers shown in FIG. 1(a) described above. For example, the processing chips (114, 124) shown in FIG. 1(b) may include processors (111, 121) and memories (112, 122). The processors (111, 121) and memories (112, 122) shown in FIG. 1(b) may perform the same functions as the processors (111, 121) and memories (112, 122) shown in FIG. 1(a) described above.

[0039] In the following description, the terms mobile terminal, wireless device, wireless transmit / receive unit (WTRU), user equipment (UE), mobile station (MS), mobile subscriber unit, user, user STA, network, base station, Node-B, access point (AP), repeater, router, relay, receiving device, transmitting device, receiving STA, transmitting STA, receiving device, transmitting device, receiving apparatus, and / or transmitting apparatus refer to the STAs (110, 120) shown in FIG. 1(a) / (b) or the processing chips (114, 124) shown in FIG. 1(b). In other words, the technical features of this specification may be performed by the STAs (110, 120) shown in FIG. 1(a) / (b), or may be performed only by the processing chips (114, 124) shown in FIG. 1(b). For example, the technical feature of the transmitting STA transmitting a control signal can be understood as the technical feature of the control signal generated in the processor (111, 121) shown in Figure 1(a) / (b) being transmitted via the transceiver (113, 123) shown in Figure 1(a) / (b). Alternatively, the technical feature of the transmitting STA transmitting a control signal can be understood as the technical feature of the control signal being generated in the processing chip (114, 124) shown in Figure 1(b) and transmitted to the transceiver (113, 123).

[0040] For example, the technical feature of the receiving STA receiving the control signal can be understood as the technical feature of the control signal being received by the transceiver (113, 123) shown in Fig. 1(a). Alternatively, the technical feature of the receiving STA receiving the control signal can be understood as the technical feature of the control signal received by the transceiver (113, 123) shown in Fig. 1(a) being acquired by the processor (111, 121) shown in Fig. 1(a). Alternatively, the technical feature of the receiving STA receiving the control signal can be understood as the technical feature of the control signal received by the transceiver (113, 123) shown in Fig. 1(b) being acquired by the processing chip (114, 124) shown in Fig. 1(b).

[0041] Referring to Figure 1(b), software code (115, 125) is contained within memory (112, 122). The software code (115, 125) contains instructions that control the operation of the processor (111, 121). The software code (115, 125) may be contained in a variety of programming languages.

[0042] The processors (111, 121) or processing chips (114, 124) shown in FIG. 1 may include an ASIC (application-specific integrated circuit), other chipsets, logic circuits, and / or data processing devices. The processors are APs (application processors). For example, the processors (111, 121) or processing chips (114, 124) shown in FIG. 1 may include at least one of a DSP (digital signal processor), a CPU (central processing unit), a GPU (graphics processing unit), and a modem (modulator and demodulator). For example, the processors (111, 121) or processing chips (114, 124) shown in FIG. 1 may include a SNAPDRAGON® processor manufactured by Qualcomm®. TMEXYNOS® series processor manufactured by Samsung® TM series processors, A-series processors manufactured by Apple®, HELIO® manufactured by MediaTek® TM ATOM® series processors, manufactured by INTEL® TM It is a series processor or an enhanced version of it.

[0043] In this specification, an uplink refers to a link for communication from a non-AP STA to an AP STA, and uplink PPDUs / packets / signals, etc. are transmitted via the uplink. Also, in this specification, a downlink refers to a link for communication from an AP STA to a non-AP STA, and downlink PPDUs / packets / signals, etc. are transmitted via the downlink.

[0044] WLAN sensing technology is a type of radar technology that can be implemented without standards, but it is believed that more powerful performance can be achieved through standardization. The IEEE802.11bf standard defines devices participating in WLAN sensing by function as shown in the table below. Depending on their function, they can be classified into devices that initiate WLAN sensing, devices that participate, devices that send sensing PPDUs (Physical Layer Protocol Data Units), and devices that receive them.

[0045] [Table 1]

[0046] FIG. 2 shows an example of a wireless LAN sensing scenario using multiple sensing transmitters.

[0047] FIG. 3 shows an example of a wireless LAN sensing scenario using multiple sensing receivers.

[0048] Figures 2 and 3 show sensing scenarios based on the functions and arrangement of a WLAN sensing device. In an environment assuming one sensing initiator and multiple sensing participants, Figure 2 shows a scenario using multiple sensing PPDU transmitters, and Figure 3 shows a scenario using multiple sensing PPDU receivers. Assuming that the sensing PPDU receiver includes a sensing measurement signal processor, in the case of Figure 3, an additional procedure is required to transmit (feed back) the sensing measurement results to the sensing initiator (STA5).

[0049] FIG. 4 shows an example of a wireless LAN sensing procedure.

[0050] The WLAN sensing procedure involves discovery, negotiation, measurement exchange, teardown, etc. between a WLAN sensing initiator and a participating device. Discovery is a process of determining the sensing capabilities of the WLAN devices, negotiation is a process of determining sensing parameters between the sensing initiator and participating devices, measurement exchange is a process of transmitting a sensing PPDU to transmit sensing measurement results, and teardown is a process of terminating the sensing procedure.

[0051] Figure 5 shows an example of classification of wireless LAN sensing.

[0052] WLAN sensing can be classified into CSI-based sensing, which uses channel state information of a signal that leaves the transmitter, travels through a channel, and reaches the receiver, and radar-based sensing, which uses the signal received after the transmitted signal is reflected by an object. Each sensing technology can also be further divided into methods in which the sensing transmitter directly participates in the sensing process (coordinated CSI, active radar) and methods in which the sensing transmitter does not participate in the sensing process, i.e., there is no dedicated transmitter participating in the sensing process (un-coordinated CSI, passive radar).

[0053] Figure 6 shows indoor positioning using CSI-based WLAN sensing.

[0054] Figure 6 shows the application of CSI-based WLAN sensing to indoor positioning. By using CSI to obtain the angle of arrival and time of arrival, and then converting these into Cartesian coordinates, indoor positioning information can be obtained.

[0055] FIG. 7 shows an example of a wireless LAN sensing device.

[0056] Figure 7 shows the implementation of a WLAN sensing device using the MATLAB toolbox, Zynq, and USRP. The MATLAB toolbox generates an IEEE802.11ax WLAN signal, and the Zynq SDR (Software Defined Radio) generates an RF signal. The signal that passes through the channel is received by the USRP SDR, and sensing signal processing is performed by the MATLAB toolbox. Here, we assumed one reference channel (a channel that can be received directly from the sensing transmitter) and one surveillance channel (a channel that can be received after being reflected by an object). Analysis using the WLAN sensing device revealed unique characteristics that can distinguish between movement and body movements.

[0057] Currently, the IEEE802.11bf WLAN sensing standardization is in the initial development stage, and cooperative sensing technology to improve sensing accuracy will be given priority in the future. Key standardization themes are expected to include sensing signal synchronization technology for cooperative sensing, CSI management and utilization technology, sensing parameter negotiation and sharing technology, and scheduling technology for CSI generation. Other key topics to be considered include long-distance sensing technology, low-power sensing technology, sensing security, and privacy protection technology.

[0058] IEEE802.11bf WLAN sensing is a type of radar technology that utilizes common WLAN signals, which are readily available anywhere and at any time. The table below shows some typical IEEE802.11bf use cases, which can be used in a wide range of real-life applications, including indoor detection, motion recognition, health management, 3D vision, and vehicle interior detection. Since it is primarily used indoors, the operating range is within 10-20 meters, and the maximum distance accuracy is no more than 2 meters.

[0059] [Table 2-1]

[0060] [Table 2-2]

[0061] [Table 2-3]

[0062] [Table 2-4]

[0063] FIG. 8 shows a modified example of the transmitting device and / or receiving device of this specification.

[0064] Each device / STA in sub-drawings (a) / (b) of Figure 1 can be modified as shown in Figure 8. The transceiver 830 in Figure 8 is the same as the transceivers 113 and 123 in Figure 1. The transceiver 830 in Figure 8 can include a receiver and a transmitter.

[0065] The processor 810 in Figure 8 is the same as the processors 111 and 121 in Figure 1. Alternatively, the processor 810 in Figure 8 is the same as the processing chips 114 and 124 in Figure 1.

[0066] The memory 820 in Figure 8 is the same as the memories 112 and 122 in Figure 1. Alternatively, the memory 820 in Figure 8 is a separate external memory different from the memories 112 and 122 in Figure 1.

[0067] 8, a power management module 811 manages power to the processor 810 and / or the transceiver 830. A battery 812 provides power to the power management module 811. A display 813 outputs results processed by the processor 810. A keypad 814 receives inputs used by the processor 810. The keypad 814 can be displayed on the display 813. A SIM card 815 is an integrated circuit used to securely store an international mobile subscriber identity (IMSI) and associated keys used to identify and authenticate subscribers on mobile phone devices such as mobile phones and computers.

[0068] 8, the speaker 840 can output sound-related results processed by the processor 810. The microphone 841 can receive sound-related inputs used by the processor 810.

[0069] 11SENS takes into consideration the signal transmission and reception methods of 60 GHz Wi-Fi technologies 802.11ad and 802.11ay to sense the movements and gestures of STAs or people using 60 GHz Wi-Fi signals. This specification proposes a sensing start frame, a transmission start frame, and a sensing signal configuration method for channel estimation between an AP and a STA or between STAs for efficient Wi-Fi sensing, as well as a sensing sequence for transmitting and receiving the sensing start frame, transmission start frame, and sensing signal.

[0070] The STAs described below are the devices of Figure 1 and / or Figure 8. The devices may be APs or non-AP STAs.

[0071] WLAN (Wireless Local Area Network) was introduced for short-range data transmission using unlicensed spectrum. IEEE 802.11 MAC / PHY-based WLAN (e.g., Wi-Fi) has become the dominant technology, with deployments now occurring almost everywhere.

[0072] WLAN (eg, Wi-Fi) was designed for the transmission of data signals, but has recently expanded its use for purposes other than data transmission.

[0073] A WLAN (e.g., Wi-Fi) signal transmitted from a transmitting end to a receiving end can include information about the transmission channel environment between the two transmitting and receiving ends. WLAN sensing is a technology that processes information about the transmission channel environment acquired through the WLAN signal to obtain cognitive information about various surrounding environments.

[0074] For example, cognitive information may include information obtained through techniques such as gesture recognition, fall detection by elder people, intrusion detection, human motion detection, health monitoring, and pet movement detection.

[0075] Additional services can be provided through cognitive information, and WLAN sensing can be applied and used in various ways in real life. To improve the accuracy of WLAN sensing, one or more devices with WLAN sensing capabilities can be used for WLAN sensing. WLAN sensing using multiple devices can obtain more accurate sensing information by using multiple information about the channel environment compared to methods using a single device (i.e., a transmitter / receiver).

[0076] WLAN (e.g., Wi-Fi) transmission is performed in a wide band using channel aggregation, channel bonding, etc. Further, WLAN transmission in an even wider band is being discussed.

[0077] Recently, there has been growing interest in WLAN devices that perform sensing using WLAN signals, and IEEE802.11 has formed a study group to discuss this. WLAN sensing can include a variety of scenarios.

[0078] FIG. 9 shows an example of WLAN sensing.

[0079] Referring to FIG. 9, there may be a target to be sensed, and there may be an STA sensing the target. For example, an AP and an STA may perform sensing. A target may exist between the AP and the STA. For example, the AP may transmit a sensing signal to the STA, and the STA may transmit a feedback signal for the sensing signal to the AP. That is, the AP may transmit a signal to identify the sensing target, and the STA may receive and measure the signal affected by the target. The STA may transmit the measurement result to the AP, and the AP may identify the target based on the measurement result.

[0080] Basically, for WLAN sensing, the steps shown in FIG. 10 can be followed.

[0081] FIG. 10 is a flow chart showing the procedure for WLAN sensing.

[0082] 1) Setup Phase (Capability Advertisement & Negotiation): A step of exchanging sensing-related capabilities and establishing an association. Through this process, the STA can determine whether sensing is possible and whether it has the appropriate sensing capability, and then perform the association. The Setup Phase can also be called the Discovery & Association Phase.

[0083] 2) Negotiation Phase (can include Grouping if necessary): Negotiation is performed on the role of each STA related to sensing and the parameters used during sensing. By using these negotiated roles and parameters, these negotiated roles / parameters can be used in multiple sensing sessions before being torn down. The Negotiation Phase can also be called the Setup Phase.

[0084] 3) Sensing Phase (performing measurement and feedback / reporting during a sensing session): This refers to the step of transmitting a sensing signal to identify a target and receiving and measuring the signal from the target. One cycle of this step can be defined as a sensing session.

[0085] 4) Tear down: You can go through the negotiation process to reset the negotiated role and parameters and start the sensing session again.

[0086] In this specification, the role of a Sensing STA is defined as follows:

[0087] Sensing initiator: STA that initiates a WLAN sensing session

[0088] Sensing responder: A STA that participates in a WLAN sensing session initiated by a sensing initiator.

[0089] Sensing transmitter: STA that transmits PPDUs used for sensing measurements in a sensing session

[0090] Sensing receiver: A STA that receives the PPDU transmitted by the sensing transmitter and performs sensing measurements.

[0091] This specification focuses on the negotiation phase and the sensing phase, and the operation in the sensing phase can change depending on the negotiation phase.

[0092] The names in this specification may be changed, and the STA may include an AP STA or a non-AP STA. Also, a STA capable of sensing is referred to as a SENS STA.

[0093] The negotiation phase can be carried out through an exchange by defining a new negotiation frame, such as the ADDBA request / response frame for the existing BA (Block Acknowledgment) agreement.

[0094] In this specification, a frame transmitted by a STA that initiates a negotiation is referred to as a SENS request frame, and a frame transmitted by a STA that responds to the SENS request frame is referred to as a SENS response frame. Also, a SENS STA that transmits a SENS request frame is referred to as a SENS RQSTA, and a SENS STA that transmits a SENS response frame is referred to as a SENS RPSTA.

[0095] The SENS Request frame can be defined as a control frame such as RTS / CTS or an action frame such as ADDBA Request / Response. Figure 11 shows an example defined in an action frame. Details of the control role / parameter and timeout will be mentioned later.

[0096] FIG. 11 shows an example of a sensing action frame.

[0097] Referring to Figure 11, if Category is 1 and Code is 32, the action frame is used for WLAN sensing, if the Sensing Action value is 0, it becomes a Sensing Request frame, and if the Sensing Action value is 1, it becomes a Sensing Response frame.

[0098] <Negotiation Procedure>

[0099] FIG. 12 shows an example for a Basic SENS Request / Response frame exchange.

[0100] As shown in Figure 12, when SENS STA1 sends a SENS Request, SENS STA2 responds with a SENS Response and negotiates for sensing. It can also respond with an ACK for each frame. If the SENS RPSTA can perform processing within a SIFS and respond to the negotiation, it can also respond with a SENS Response after the SIFS in which it receives the SENS Request frame.

[0101] The method described below basically excludes the part that responds with ACK, ie, sending a SENS Response after SIFS, but may include a response using ACK, ie, sending a SENS Response after SIFS.

[0102] Based on FIG. 12, depending on the environment in which the SENS STA exists, there are the following specific SENS request / response frame exchange methods for determining which STA should perform negotiation and how to perform it, but the method is not limited to these.

[0103] Basically, there are two main methods: sending a SENS request independently to each SENS STA, and sending a SENS request to multiple SENS STAs in a manner such as broadcast / multicast. This transmission method can be indicated in the mode format of the SENS request, and it can be determined whether it is an individually addressed frame or a broadcast by implicitly looking at the RA (Receiver Address). Also, if only one of these transmission methods is fixed, it is not indicated in the mode format. For example, if the mode is indicated with 1 bit, broadcast can be indicated when mode = 1, and unicast can be indicated when mode = 0. In the embodiment described below, the mode is not separately indicated, but each SENS request can include this mode indicator.

[0104] Although the following describes methods 1) and 2) separately, they can both be applied during the negotiation process. For example, depending on the channel conditions, the SENS STA can transmit independently at the beginning of the negotiation, and then the transmission mode can be switched to transmit to multiple SENS STAs.

[0105] FIG. 13 shows an embodiment 1) in which a SENS Request is sent independently to SENS STAs within one BSS.

[0106] 1) Send an independent (unicast) SENS Request to known SENS STAs (e.g., SENS STAs within one BSS).

[0107] Referring to FIG. 13, a SENS RQ STA (STA1) transmits a SENS Request to STA2 and STA3, respectively, and receives a SENS Response frame.

[0108] This method can reliably execute negotiation for each STA, but the more SENS STAs there are, the larger the delay and signaling overhead becomes. The methods to solve this are as follows, and are also described in method 2), but are not limited to this.

[0109] 1-1) After a certain time, the SENS RQSTA does not send a SENS Request by itself.

[0110] -The SENS RQSTA can reduce the request, but other SENS STAs cannot know whether any more SENS Request frames are coming.

[0111] FIG. 14 shows an embodiment 1-2) in which a timer is operated and a SENS request is sent until the timer expires.

[0112] 1-2) Using a Timer

[0113] At or after the first SENS Request transmission, the timer is started and the SENS Request is sent until it expires. Therefore, this timer information must be included in the SENS Request frame.

[0114] 14, the SENS RQ STA (STA1) indicates timer information in the SENS Request frame to be sent to SENS STA2, and starts the timer. The SENS Request frame to be sent to STA3 indicates the remaining timer information. In response, the other SENS STAs can know how long the SENS RQ STA will continue to send SENS Requests.

[0115] FIG. 15 shows an embodiment 1-3) in which another STA is notified that it will no longer transmit SENS Request frames.

[0116] 1-3) Announcement of Negotiation Completion

[0117] - Announces that it will not send any more SENS Request frames to other STAs. It can either make an explicit indication of the last SENS Request frame or send a new SENS completion frame.

[0118] Referring to FIG. 15, SENS STA1 includes an explicit indication that negotiation is complete in the final SENS Request frame it sends to STA3.

[0119] FIG. 16 shows an embodiment 1-3) in which a SENS Completion frame is transmitted to notify completion of negotiation.

[0120] Referring to FIG. 16, after transmitting all SENS Request frames to the intended SENS STAs, the SENS STA1 transmits a SENS Completion frame to indicate that the negotiation is complete.

[0121] => The Timer method can change the number of STAs that can participate in the sensing session depending on the channel status, but this method allows the SENS RQ STA to end the negotiation by announcing when desired.

[0122] The above methods can be implemented separately or in combination. For example, a timer can be running, but the completion of the negotiation can be announced in advance before the timer expires.

[0123] ◇ Consideration of failure cases for Intended SENS RPSTA

[0124] FIG. 17 shows an example of applying a timeout that takes into account failure cases for an Intended SENS RPSTA.

[0125] In the above method, a SENS RPSTA (e.g., STA2, STA3) may not be able to receive a SENS Request, or a SENS Response it sent may not be received by a SENS RQSTA (e.g., STA1). Therefore, the SENS RQSTA may continuously send a SENS Request, which may lengthen the overall negotiation process, or may result in insufficient STAs participating in Sensing due to repeated transmissions to the same STA. Therefore, the SENS RQSTA may apply an appropriate timeout value to each SENS RPSTA.

[0126] 17, STA1 sets a timeout and sends a SENS Request to STA2. The first transmission fails to send a SENS Response correctly, or the second transmission fails to send a SENS Request correctly. After that, due to the timeout, STA1 determines that the channel with STA2 is not good and does not send any more SENS Request frames to STA2.

[0127] ◇Failure cases for 3rd party STA are considered

[0128] Basically, STAs that are not intended receivers need to overhear the timer information or negotiation completion information sent via an explicit indicator. However, due to issues such as channel conditions and coverage, it is not always possible to guarantee that this information has been decoded. Therefore, there are several methods, as follows:

[0129] A. Always send SENS Request and / or SENS Response at the basic rate (e.g., MCS0).

[0130] The above-mentioned SENS Request / Response frame can be transmitted at a high rate other than a low rate such as MCS0 depending on the channel conditions. However, to increase the probability of overhearing for the third part STA during the negotiation process, the frame can be requested to be transmitted at a fixed basic rate (e.g., the lowest MCS (MCS0)).

[0131] B. During negotiation, a basic rate (e.g., MCS0) is used to transmit a broadcast frame containing timer information and negotiation completion information to increase reliability.

[0132] This broadcast frame can reuse the SENS Request frame, or can be defined as a new frame. If the SENS Request frame is reused, the frame is converted to a mode in which it is only transmitted for reliability, i.e., no response is made to it, as in the example of Figure 18, or to a mode in which it is transmitted in broadcast form and receives a response, as in method 2) described below, as in the example below of Figure 18. Details of method 2) will be described below.

[0133] FIG. 18 shows an example in which timer information and negotiation completion information are included in a Broadcast SENS Request frame.

[0134] 2) A SENS Request is sent (for example, broadcast) to multiple SENS STAs and a SENS Response is received from each. A SENS Request can also be sent more than once.

[0135] FIG. 19 shows an example of broadcasting a SENS Request to multiple SENS STAs.

[0136] 19, a SENS RQ STA (STA1) receives SENS Response frames from STA2, STA3, and STA4, respectively. As shown in the following example, the SENS RQ STA (STA1) can transmit SENS Requests multiple times to improve reliability. Similarly, to improve reliability, the SENS Request and / or SENS Response frames can be requested to be transmitted at a basic rate (e.g., MCS0).

[0137] This method can be specifically implemented as follows, but is not limited thereto. In particular, methods 1-1), 1-2), and 1-3) described in 1) can be utilized.

[0138] 2-1) After a certain time, the SENS RQSTA does not send a SENS Request by itself.

[0139] -The SENS RQSTA can reduce the request, but other SENS STAs cannot know whether any more SENS Request frames are coming.

[0140] 2-2) When sending a SENS request, specify the STA ID for which you want a response.

[0141] The SENS RQ STA indicates the STA ID for which a response is desired in the SENS Request frame and receives a response from the corresponding SENS STA.

[0142] FIG. 20 shows an embodiment 2-2) in which the STA ID for which a response is desired is specified when a SENS request is sent.

[0143] 20, the SENS RQ STA (STA1) specifies the IDs of STA2 and STA3 in the SENS Request frame and receives SENS Responses from STA2 and 3. STA4 does not send a SENS Response because it was not specified.

[0144] => In particular, if processing within a SIFS interval is possible using the STA ID, an order can be determined and transmitted sequentially, or 11ax's OFDMA (Orthogonal Frequency Division Multiple Access) can be used.

[0145] FIG. 21 shows an example of sequential response to SIFS intervals in Example 2-2).

[0146] 21, the SENS RQ STA (STA1) specifies the IDs of STA2 and STA3 and the response order (STA2 → STA3) in the SENS Request frame, and receives SENS Responses from them at SIFS intervals. Here, ACKs sent by STA1 may also be present SIFS after receiving the SENS Responses.

[0147] ◇Failure case consideration for SENS RPSTA

[0148] In the above method, the SENS RP STA (e.g., STA2, STA3, STA4) may not be able to receive the SENS Request, or the SENS Response it sent may not be received by the SENS RQ STA (e.g., STA1). Therefore, transmission at SIFS intervals may not work properly. To solve this, PIFS recovery may be used or back-off may be performed again. That is, as shown in the example of FIG. 22, if no response arrives within PIFS after STA2's response, the SENS Request may be sent again. Alternatively, as shown in the following example, if a timeout for the response occurs after STA2's response, the SENS Request may be sent again via back-off.

[0149] FIG. 22 shows an example in which the failure case is taken into consideration in the method using SIFS in Example 2-2).

[0150] FIG. 23 shows an example of an OFDMA response at SIFS intervals in Example 2-2).

[0151] 23, when STA1, STA2, and STA3 are STAs having at least 11ax capability, the SENS RQ STA (STA1) indicates the IDs and RU allocation information of STA2 and STA3 in a SENS Request frame and receives SENS Responses from the RUs that have received each allocation. Here, the SENS Request frame can be a new trigger frame or a trigger frame of a new trigger type.

[0152] 2-3) When sending a SENS request, set a timer to receive the SENS response.

[0153] As in 1), the delay until a response is received from all SENS STAs can be increased, so a timer can be set.

[0154] FIG. 24 shows an example of setting a timer for receiving a response for the SENS STA.

[0155] 24, the SENS RQ STA (STA1) indicates timer information in the SENS Request frame and starts the timer. In response, other SENS STAs can know how long the SENS RQ STA will send the SENS Request. Therefore, after the timer expires, STA4 does not send a SENS Response.

[0156] 2-4) SENS completion announcement

[0157] - Announce that it will not send any more SENS Request frames to other STAs. It may send a new SENS completion frame or include an explicit indication that it will complete the negotiation in the SENS Request frame.

[0158] FIG. 25 shows an example 2-4) of sending a new SENS completion frame or including an explicit indicator to complete the negotiation in the SENS Request frame.

[0159] 25, when SENS STA1 determines that negotiation is complete, it notifies the STA1 that negotiation is complete via a SENS Completion frame or an explicit indicator. STA4 receives this frame and does not respond.

[0160] The above methods can be implemented separately or in combination. For example, a timer can be running, but the completion of the negotiation can be announced in advance before the timer expires.

[0161] <Role Negotiation>

[0162] During the negotiation or other phase, the four roles mentioned above must be defined between SENS STAs.

[0163] -Sensing initiator and sensing responder

[0164] -In the simplest case, the sensing initiator can be the STA that sent the SENS Request frame. In other words, the SENS RQ STA becomes the sensing initiator. This does not require a separate signaling overhead to define the initiator and responder. Also, since one SENS STA basically performs the role of sensing initiator, once the initiator is determined, the remaining SENS STAs become sensing responders.

[0165] This role negotiation method can vary depending on whether the SENS Request frame is sent via unicast or broadcast.

[0166] 1) Broadcast method

[0167] 1-1) Mode setting

[0168] -This role can be divided into modes depending on which role the SENS Initiator and Responder perform, either transmitter or receiver. For example, modes can be classified as follows, but are not limited to these.

[0169] Mode 1: SENS RQSTA becomes the transmitter and SENS RPSTA becomes the receiver.

[0170] Mode 2: SENS RQSTA becomes the receiver, and SENS RPSTA becomes the transmitter

[0171] The mode can be indicated in the SENS Request frame and / or SENS Response frame. If there are two modes, it is 1 bit. For example, if it is 1, it operates in Mode 1, and if it is 0, it operates in Mode 2. If there are more modes, the number of bits to indicate them can be increased.

[0172] Although the method of specifying two modes can reduce signaling overhead, it is not easy to determine multiple sensing transmitters or sensing receivers including SENS RQSTA.

[0173] FIG. 26 shows an example of role negotiation based on method 1-1).

[0174] 26, when the SENS RQ STA (STA1) specifies Mode 1 in the SENS Request frame and STA2 and STA3 respond to it, STA1 is the SENS initiator and transmitter at the same time, while STA2 and STA3 are responders and receivers at the same time.

[0175] Also, when the SENS RQSTA (STA1) specifies Mode 2 in the SENS Request frame and STA2 and STA3 respond to it, STA1 becomes the SENS initiator and receiver at the same time, while STA2 and STA3 become responders and transmitters at the same time.

[0176] In the above example, the SENS RQSTA (STA1) instructs, but the SENS RPSTAs (STA2, STA3) can also instruct Mode1 or Mode2 in the SENS Response frame in response to this.

[0177] The above example shows how the transmitter and receiver are determined by the SENS initiator in mode 1 / 2, but there are also methods for more dynamic role negotiation.

[0178] 1-2) With mode indication, the role is determined by an additional STA identification indication.

[0179] When SENS RQSTA specifies a mode and additionally specifies a STA ID, the STA corresponding to the corresponding STA ID executes a role similar to SENS RQSTA. For example, as shown in Figure 20, in Mode 1, if the ID of STA2 is additionally specified, STA2 also becomes a sensing transmitter because STA1 is a sensing transmitter in Mode 1. In Mode 2, if the ID of STA3 is additionally specified, STA3 becomes a receiver because STA1 is a sensing receiver in Mode 2.

[0180] FIG. 27 shows an example of role negotiation based on method 1-1).

[0181] Referring to Figure 27, when the SENS RQ STA specifies a mode and additionally specifies a STA ID, the STA corresponding to the corresponding STA ID performs a role similar to that of an initiator. For example, in the case of Mode 1 as shown in Figure 26, if the ID of STA2 is additionally specified, STA2 also becomes a transmitter because STA1 is a transmitter in Mode 1. In the case of Mode 2, if the ID of STA3 is additionally specified, STA3 becomes a receiver because STA1 is a receiver in Mode 2.

[0182] In conclusion, when methods 1-1) and 1-2) are considered comprehensively, the fields can be configured as follows. Although Figures 26 and 27 show Sensing Response via back-off, methods such as the Sensing Response transmission in Figures 21 and 23 described above can also be used.

[0183] A.STA ID List and Role Bitmap

[0184] Each STA ID is indicated, and then the bitmap corresponding to each STA indicates whether it is a transmitter (e.g., 1) or a receiver (e.g., 0). Here, the bitmap can be parsed through the Explicit Number of STAs indication, but the Number of STAs is not necessarily required as it can be inferred through the STA ID List.

[0185] The Role Bitmap can be configured in 8-bit units for decoding, or it can be configured as many times as the number of STAs included in the STA ID List. However, it is generally more stable from a decoding perspective to configure the bitmap in 8-bit units as before. On the other hand, to explicitly specify the bitmap size, you can use the bitmap size instead of the number of STAs. For example, when configured in 8-bit units, a value of 2 is 16 bits, and a value of 1 is 8 bits.

[0186] B. Tuple<STA ID、Role>

[0187] That is, the role (Transmitter or Receiver) can be indicated by one bit after the STA ID without separately configuring the bitmap. As with A, the number of STAs can be indicated here, but this is not necessarily required since it can be inferred from the number of tuples.

[0188] C.STA ID List+Overall Role

[0189] In methods A and B, the role of each STA is specified flexibly, but if the roles of the initiator and responder are always different during sensing, the role can be specified with a single bit. For example, if the initiator specifies a value of 1 for the transmitter, all responders that receive this and respond will become transmitters, and the initiator will become receivers.

[0190] FIG. 28 shows how to specify a role using methods A, B, and C.

[0191] Referring to FIG. 28, STA1, which is the initiator, determines the role of each of STA2, 3, and 4 through a Sensing Request. At this time, if STA2, 3, and 4 transmit simultaneously for OFDMA / MIMO, each STA can check whether it is currently capable of sensing (for example, whether the channel is idle) based on whether it is transmitting. In this example, the Sensing Request frame announces that STA2, 3, and 4 are sensing transmitters and STA1 is the receiver. Method A uses each STA's ID and an 8-bit bitmap, and since there are three STAs, the first 3 bits are set to 1 and the rest are reserved. Method B uses the STA ID and 1 bit (each value is 1) for each STA, while Method C specifies the STA ID first and then specifies 1 bit for STA2, 3, and 4 as transmitters.

[0192] 1-3) The role is determined by the Without mode indication and STA identification indication.

[0193] FIG. 29 shows an example of role negotiation based on method 1-3).

[0194] 29, the SENS RQSTA specifies a role for each STA ID. For example, as shown in the example of FIG. 26, the transmitter specifies the IDs of STA1 and STA2, and the receiver specifies the ID of STA3 to determine the role.

[0195] Although FIG. 29 shows a sensing response via back-off, methods such as the sensing response transmission in FIGS. 21 and 23 described above can also be used.

[0196] 2) Unicast method

[0197] 2-1) Mode setting

[0198] As in the method 1-1), a mode can be set. For example, the modes can be classified as follows, but are not limited to these.

[0199] Mode 1: SENS RQSTA becomes the transmitter and SENS RPSTA becomes the receiver.

[0200] Mode 2: SENS RQSTA becomes the receiver and SENS RPSTA becomes the transmitter.

[0201] Mode 3: SENS RQSTA becomes the transmitter and SENS RPSTA becomes the transmitter.

[0202] Mode 4: SENS RQSTA becomes the receiver, and SENS RPSTA becomes the receiver.

[0203] The mode can be indicated in the SENS Request frame and / or SENS Response frame. If there are four modes, it is 2 bits. For example, if it is 00, it operates in Mode 1, and if it is 11, it operates in Mode 4. If there are more modes, the number of bits to indicate them can be increased.

[0204] FIG. 30 shows an example of role negotiation based on method 2-1).

[0205] 30, when a SENS RQ STA (STA1) sends a SENS Request frame instructing STA2 to use Mode 1 and STA3 to use Mode 3, and STA2 and STA3 each respond, STA1 becomes the sensing initiator and transmitter at the same time, whereas STA2 becomes the sensing responder and receiver, and STA3 becomes the responder and a sensing transmitter like STA1.

[0206] Also, if the SENS RQSTA (STA1) specifies Mode 2 in the SENS Request frame and specifies Mode 4 to STA3, and STA2 and STA3 each respond, STA1 becomes both the sensing initiator and receiver, while STA2 becomes the sensing responder and transmitter, and STA3 becomes both the responder and a sensing receiver like STA1.

[0207] In the above example, the SENS RQSTA (STA1) indicates the mode, but the SENS RPSTAs (STA2, 3) can also indicate the mode in the SENS Response frame in response to this. The roles can be negotiated as follows according to the indications of the RQSTA and RPSTA:

[0208] 2-2) Negotiation by role instructions of RQSTA and RPSTA

[0209] Each RQSTA and RPSTA can indicate with one bit whether it will act as a transmitter or receiver, or can indicate with the above-mentioned mode, as follows.

[0210] The following table shows negotiation example #1 based on the role instructions of RQSTA and RPSTA.

[0211] [Table 3]

[0212] The following table shows negotiation example #2 using the role instructions of RQSTA and RPSTA.

[0213] [Table 4]

[0214] The above example shows a case where negotiation is possible when the roles between the RQSTA and RPSTA do not overlap or are indicated in the same mode. In other words, the vacant determined role in the above example is a case where accurate negotiation is not possible due to confusion. However, in this vacant portion, the role can be determined according to a rule predetermined between the two STAs. For example, if the RQSTA indicates both transmitter and receiver (11) and the RPSTA indicates only receiver (01), the RQSTA becomes the transmitter. Such a rule can vary depending on how it is predetermined.

[0215] The role negotiation can be dynamically instructed by the initiator before executing each sensing operation after identifying the STAs participating in sensing and negotiating parameters in the negotiation phase. This is closely related to the method for determining the role of each STA, as in method 1-2). That is, it is necessary to instruct the STAs on which role to play. Specific methods are as follows, but are not limited thereto.

[0216] A.STA ID List and Role Bitmap

[0217] Each STA ID is indicated, and then the bitmap corresponding to each STA indicates whether it is a transmitter (e.g., 1) or a receiver (e.g., 0). Here, the bitmap can be parsed through the Explicit Number of STAs indication, but the Number of STAs is not necessarily required as it can be inferred through the STA ID List.

[0218] The Role Bitmap can be configured in 8-bit units for decoding, or it can be configured as many times as the number of STAs included in the STA ID List. However, it is generally more stable from a decoding perspective to configure the bitmap in 8-bit units as before. On the other hand, to explicitly specify the bitmap size, you can use the bitmap size instead of the number of STAs. For example, when configured in 8-bit units, a value of 2 is 16 bits, and a value of 1 is 8 bits.

[0219] B. Tuple<STA ID、Role>

[0220] That is, the role (Transmitter or Receiver) can be indicated by one bit after the STA ID without separately configuring the bitmap. As with A, the number of STAs can be indicated here, but this is not necessarily required since it can be inferred from the number of tuples.

[0221] C.STA ID List+Overall Role

[0222] In methods A and B, the role of each STA is specified flexibly, but if the roles of the initiator and responder are always different during sensing, the role can be specified with a single bit. For example, if the initiator specifies a value of 1 for the transmitter, all responders that receive this and respond will become transmitters, and the initiator will become receivers.

[0223] FIG. 31 shows how to specify a role using methods A, B, and C.

[0224] Referring to Figure 31, STA1, which is the initiator, determines the role of each of STA2, 3, and 4 through polling. At this time, when STA2, 3, and 4 transmit simultaneously for OFDMA / MIMO, each STA can check whether it is currently capable of sensing (for example, whether the channel is idle) based on whether it is transmitting. In this example, the Sensing Poll frame announces that STA2, 3, and 4 are sensing transmitters and STA1 is the receiver. Method A uses each STA's ID and an 8-bit bitmap, and since there are three STAs, the first 3 bits are set to 1 and the rest are reserved. Method B uses the STA ID and 1 bit (each value is 1) for each STA, and Method C specifies the STA ID first, and then specifies 1 bit for STA2, 3, and 4 as transmitters.

[0225] <Parameter Negotiation>

[0226] The following parameters must be determined between SENS STAs during negotiation or other phases. One or more of the parameters described below can be indicated in the SENS Request frame and / or SENS Response frame. In the following example, only indications for the SENS Request frame are shown, but they can also be indicated in the SENS Response frame. Also, in the following example, method 2) for transmitting the SENS Request frame in the negotiation procedure is assumed (e.g., broadcast), but method 1) (e.g., unicast) can also be used.

[0227] 1) Timers for Negotiation phase: Refer to the above-mentioned negotiation procedure (e.g., 1-2, 2-3) method).

[0228] 2) Timeout for Sensing phase: Timeout value related to the sensing phase (including one or more sensing sessions) after negotiation. This timeout value can be specified separately as one or both of the following:

[0229] FIG. 32 shows an embodiment 2-1) in which negotiation is torn down when sensing-related frame exchange is not performed during T_sens.

[0230] 2-1) Timeout for Tear Down: After negotiation, if no sensing-related frame exchange is performed during this time period in the sensing phase (for example, T_sens in FIG. 32), the negotiation is torn down.

[0231] FIG. 33 shows an example 2-2) in which sensing is performed during T_sens and the sensing phase is then terminated.

[0232] 2-2) Timeout for Sensing: The time during which the sensing phase is performed. That is, sensing is performed using the negotiated role / parameters during this time. As mentioned above, this process can be performed in one or more sensing sessions. As shown in Figure 28, the sensing phase ends after T_sens.

[0233] 3) Number of sensing sessions: A parameter for how many times the defined sensing session should be performed.

[0234] 4) Mode for transmitter / receiver: For this mode, reference can be made to the above-mentioned Role Negotiation (including FIG. 24).

[0235] 5) Information of SENS STA(s): Information for STAs participating in Sensing, which can refer to the Negotiation Procedure (e.g., method 2-2) described above.

[0236] 6) Group ID (GID): After the negotiation process, the negotiated STAs can be assigned an ID in one group. That is, during this sensing phase, a group ID is transmitted as shown in Figure 29 to enable identification. In Figure 29, STA1, 2, and 3 form one sensing group, and when STA1 transmits the group ID, STA2 and STA3 both participate in sensing. Using this method, if only a GID is included instead of multiple STA IDs, overhead can be reduced, but it is difficult to use a GID to execute a sensing session with some of the negotiated STAs.

[0237] FIG. 34 shows an embodiment 6) in which STA1, STA2, and STA3 form one sensing group and when STA1 transmits the group ID, STA2 and STA3 both participate in sensing.

[0238] 7) Signal Length: The transmission time of the sensing signal (sounding) sent by the transmitter in the sensing phase.

[0239] 8) Bandwidth to be measured or for feedback: The bandwidth for the sensing signal during the sensing phase or the measurement result feedback of this signal can be specified. This can be specified for all STAs or for each STA. Specifying it for all STAs reduces overhead, but if a specific STA can efficiently sense or feedback, as in the method of specifying it for each STA, it cannot be specified for such a specific frequency.

[0240] 8-1) Sensing Frequency Location: In 7), the same frequency bandwidth can be specified, but in relation to this, different measurement locations can also be specified for each STA. For example, as shown in Figure 30, out of 80 MHz, primary 40 MHz can be assigned to STA2 and secondary 40 MHz can be assigned to STA3. This example shows the case where the sensing transmitters are STA2 and STA3. Also, if the sensing STA supports 11ax OFDMA technology, a specific RU can be specified.

[0241] FIG. 35 shows an example in which STA2 is assigned a primary 40 MHz band and STA3 is assigned a secondary 40 MHz band out of 80 MHz band, and sensing signals are transmitted and received.

[0242] FIG. 35 shows an example in which STA2 is assigned a primary 40 MHz band and STA3 is assigned a secondary 40 MHz band out of 80 MHz band, and sensing signals are transmitted and received.

[0243] 9) Type of Information: Information type to be measured through sensing signal reception during the sensing phase (e.g., CSI per subcarrier)

[0244] 10) Signal Type: Type of sensing signal during the sensing phase (e.g., NDP, NDPA+NDP, New signal type)

[0245] 11) Order of reports / sensing: To prevent collisions when transmitting a sensing signal or feedbacking information about signal measurement, the STA can be explicitly told to send a report. For example, the order in which the STA information in 4) is indicated can be considered to be the order. If this information is indicated and Figure 30 is assumed, the order of STA2 and STA3, which are sensing transmitters, is STA2->STA3.

[0246] 12) Session ID: An ID for a session that uses the role and parameters determined through this negotiation phase. As mentioned above, one SENS STA can simultaneously execute multiple sensing applications, and multiple SENS STAs can also simultaneously execute sensing applications. That is, if the sensing procedures for each application are executed simultaneously, multiple sessions can overlap, so the SENS STAs must distinguish between these sessions and execute sensing. Therefore, a session ID can be specified.

[0247] FIG. 36 shows an example of a sensing procedure in which a Session ID is used.

[0248] Referring to Figure 36, when STA1 sends a session ID, STA2 and STA3 recognize this session ID. Therefore, when they receive this session ID in the sensing phase, they can perform sensing according to the negotiated role and parameters.

[0249] <Sensing Phase regarding Negotiation>

[0250] If the negotiation process is completed, the sensing phase is performed based on the negotiated roles and parameters. Basically, the sensing phase can be performed in one or more sensing sessions as mentioned above, and a frame that can start a sensing session can exist. In this specification, this frame is called a SENS Initiation frame. The SENS Initiation frame can indicate all or part of the parameters described in the parameter negotiation.

[0251] FIG. 37 shows an example in which the SENS initiation frame is transmitted multiple times.

[0252] For example, basically, STA information, Group ID, Session ID, etc. may be included for one sensing session. As shown in Figure 37, the SENS initiation frame may be transmitted once or multiple times. For example, if the STA participating in the sensing phase is changed, the frame may be transmitted multiple times.

[0253] FIG. 38 shows an example in which a SENS initiation frame is transmitted for each sensing session.

[0254] In addition, the SENS initiation frame can be transmitted only once during the sensing phase, as shown in FIG. 38, A. at the start of all sensing sessions, B. at the start of some sensing sessions, or C.

[0255] In method A, each SENS STA can recognize the session through explicit signaling for the sensing session. Methods B and C require a separate instruction for the sensing signal from the sensing transmitter position and a method for recognizing the sensing signal from the sensing receiver position for some sensing sessions, but they can reduce the overhead for the initiation frame.

[0256] In FIG. 38, channel access is performed between each session, but this can also be achieved by obtaining a TXOP that can include multiple sessions, and each session can be linked via SIFS intervals.

[0257] The SENS Initiation frame can specify all or part of the parameters described in the parameter negotiation. For example, it can basically include STA information or Group ID for one sensing session.

[0258] Although not specifically disclosed in the following examples, various methods can exist in the sensing phase depending on the negotiation (e.g., the SENS RQ STA takes the role of transmitter or receiver, and the sensing signal or feedback transmission is transmitted sequentially or based on OFDMA), so detailed frame exchange is not described. Also, STA1 is assumed to be the SENS Initiator.

[0259] <Reduced negotiation phase>

[0260] FIG. 39 shows an example of the negotiation phase and reduced negotiation phase.

[0261] As mentioned above, each sensing session has a negotiation phase for WLAN sensing. Therefore, after one sensing session is completed, the negotiation phase is executed again in the next sensing session, as shown in the upper part of Figure 39. If the roles and parameters from the previous session are largely unchanged, executing the negotiation phase again would be a waste of resources. Therefore, it is possible to negotiate only the roles and parameters that are to be changed. In the present invention, this phase is called the reduced negotiation phase, and the reduced negotiation phase can be applied in the negotiation phase for the next sensing session, as shown in the lower part of Figure 39.

[0262] FIG. 40 shows another example of the negotiation phase and reduced negotiation phase.

[0263] In the reduced negotiation phase, a reduced SENS Request / Response frame can be used, which reduces overhead by including only the roles and parameters to be changed. In other words, roles and parameters that are not specified are inherited from the previous session. Also, if inheritance is selected, it is possible to immediately transition to the reduced negotiation phase, which negotiates only the roles and parameters that have changed since the previous session without a tear-down phase, as shown in Figure 40.

[0264] Including fields for unchanged roles and parameters does not reduce overhead. Therefore, you can use a reduced SENS Request / Response frame that includes only the roles and parameters that change, reducing overhead.

[0265] A control field can be applied for the role and parameter to be changed. That is, except for the fields that must be included in the SENS Request / Response frame, a field indicating whether a changed parameter exists is included. In the following examples, this parameter is called a dynamic parameter.

[0266] Based on the above basic process, the following cases can be classified depending on whether the above-mentioned negotiation procedure is used and whether the negotiated role / parameter is static or dynamic.

[0267] 1)Static negotiated roles and parameters

[0268] In this case, since the roles and parameters negotiated during the sensing phase basically remain unchanged, it is not possible to specify separately changed roles and parameters in the SENS initiation frame. However, it is possible to specify all or part of the parameters described in the parameter negotiation repeatedly in the SENS initiation frame.

[0269] 2)Dynamic negotiated roles and parameters

[0270] In this case, the roles and parameters determined during the negotiation phase during the sensing phase can be changed. Therefore, the changed parameters can be indicated in the SENS Initiation frame as shown in Figure 41. These parameters can correspond to the parameters mentioned in the parameter negotiation section above.

[0271] Figure 41 shows an example of dynamic changes to negotiated roles and parameters.

[0272] However, since including the corresponding field in the SENS Initiation frame to prepare for these dynamic parameters always involves overhead, a control field can be applied. In other words, in addition to the fields that must be included in the SENS initiation frame, a field indicating whether a dynamic parameter exists is included.

[0273] FIG. 42 is an example of a control field for a dynamic parameter.

[0274] Referring to Figure 42, as in Example 1, whether a dynamic parameter exists is first indicated (for example, using 1 bit), and if it does exist, the parameter set is then indicated. Alternatively, as in Example 2, the existence of each dynamic parameter can be indicated. Depending on the situation, if there are a large number of dynamic parameters, it is determined that Example 2 can further reduce overhead.

[0275] On the other hand, the above describes the case where negotiated parameters are changed in a single SENS initiation frame that starts a sensing session, but parameters can also be changed dynamically as shown below.

[0276] 1) When sending a SENS initiation frame or reduced SENS initiation frame within one sensing session

[0277] That is, a SENS initiation frame is sent multiple times within one sensing session, or a frame including only the dynamic role / parameter (for example, a reduced SENS initiation frame) is sent as shown in FIG.

[0278] Figure 43 shows an example of dynamic changes to roles and parameters negotiated using the reduced SENS initiation frame.

[0279] 2) Re-negotiation between sensing sessions

[0280] In other words, the negotiation phase is executed again between sensing sessions. In this process, the SENS Request / Response frame described above can be reused, but including fields for unchanged roles and parameters can result in increased overhead. Therefore, as shown in Figure 43, a reduced SENS Request / Response frame can be used, which includes only the roles and parameters that will be changed and reduces overhead. In addition to this frame exchange, the SENS initiation frame and reduced SENS initiation frame can also be used as shown in 1).

[0281] Figure 44 shows an example of dynamic changes to roles and parameters negotiated during the re-negotiation phase using the reduced SENS Request / Response frame.

[0282] Example #1: Role change

[0283] FIG. 45 shows an example of changing the role in the embodiment 2).

[0284] Referring to Figure 45, during the negotiation phase, the sensing transmitter is determined to be STA1, and the sensing receivers are determined to be STA2 and STA3. In the second sensing session, STA1 changes the sensing transmitter to STA2 and STA3 and the sensing receiver to STA1 via the SENS initiation frame to measure the channel in the other direction, and STA2 and STA3 transmit sensing signals.

[0285] Example #2: Bandwidth to be measured change

[0286] FIG. 46 shows an example of changing the bandwidth to be measured in embodiment 2).

[0287] Referring to Figure 46, the bandwidth measured during the negotiation phase is 40 MHz. In the second sensing session, STA1 changes the bandwidth to be measured to 80 MHz via the SENS initiation frame for better resolution. Therefore, sensing transmitters STA2 and STA3 transmit sensing signals using 80 MHz.

[0288] Example #3: STA information change

[0289] FIG. 47 shows an example of changing STA information in the embodiment 2).

[0290] 47, during the negotiation phase, the negotiation STAs are STA1, STA2, and STA3. Here, in the first session, only STA2 is designated and only STA2 transmits a sensing signal, and in the second session, only STA3 is designated and only STA3 transmits a sensing signal. In this way, by continuously changing the STA information, it is possible to perform a sensing session with a different STA for each session.

[0291] The dynamic method described above can be applied in some different ways: Roles / parameters changed in one sensing session can be applied continuously to subsequent sensing sessions, or they can be applied only to that sensing session, with the original negotiated parameters applied to subsequent sensing sessions.

[0292] 3) Without Negotiation Phase

[0293] In this case, there is basically no negotiation phase, so the roles and parameters mentioned above must be specified via the SENS Initiation frame during the sensing phase. This case can be divided into static / dynamic cases, such as cases 1) and 2), depending on the transmission of the SENS Initiation frame.

[0294] For example, if a SENS Initiation frame is sent in the first sensing session and not sent thereafter, it can be considered a static case, and if it is sent thereafter with changed parameters, it can be considered a dynamic case.

[0295] The above-mentioned embodiment will be described below with reference to FIGS.

[0296] FIG. 48 is a flowchart showing a procedure in which a sensing initiator according to this embodiment executes sensing.

[0297] The example of Figure 48 can be executed in a network environment where a next-generation wireless LAN system (IEEE802.11bf) is supported. The next-generation wireless LAN system is an improved version of the 802.11ad and 802.11ay systems, and can satisfy backward compatibility with the 802.11ad and 802.11ay systems.

[0298] The example of Figure 48 is performed at a first STA, which may correspond to a sensing initiator. The second and third STAs of Figure 48 may correspond to sensing responders.

[0299] This embodiment proposes a method for determining STAs that will participate in sensing in a wireless LAN system, negotiating parameters to be used for sensing, and executing a sensing procedure based on the negotiated parameters. In particular, this embodiment proposes a method for role negotiation in the negotiation step, parameter negotiation, and parameter change in the sensing step.

[0300] In step S4810, a first STA (station) broadcasts a sensing request frame.

[0301] In step S4820, the first STA receives a first sensing response frame from a second STA and receives a second sensing response frame from a third STA.

[0302] The sensing request frame includes STA identifier information and RU (Resource Unit) allocation information. The STA identifier information includes identifiers of the second and third STAs. The RU allocation information includes information on a first RU allocated to the second STA and information on a second RU allocated to the third STA.

[0303] The first sensing response frame is received via the first RU, and the second sensing response frame is received via the second RU. That is, responses to the sensing request frame can be received (simultaneously) by the second and third STAs based on Orthogonal Frequency Division Multiple Access (OFDMA). The sensing request frame can be a (newly defined) trigger frame. If the STA identifier information does not include the identifier of a fourth STA, the first STA does not receive the third sensing response frame from the fourth STA.

[0304] That is, in this embodiment, the sensing request frame indicates the identifier (ID) of the STA receiving the sensing response frame and RU allocation information, and the STA corresponding to the STA identifier can receive the sensing request frame and transmit the sensing response frame through the assigned RU after SIFS.

[0305] The sensing request frame may further include timer information for receiving the sensing response frame. The first and second sensing response frames may be transmitted before a timer according to the timer information expires. After the timer according to the timer information expires, the third sensing response frame is not transmitted. That is, the STA that receives the timer information can know until when the sensing request frame will be transmitted, and can transmit the sensing response frame before the timer expires.

[0306] The sensing request frame may further include parameter information.

[0307] The parameter information may include timer information for the negotiation step, STA role information, timeout information for the sensing step, information on the number of sensing sessions included in the sensing step, information on the first to third STAs, information on the length of the sensing signal, information on the frequency band to which the sensing signal is assigned, information on the type of information to be measured based on the sensing signal, information on the type of the sensing signal, and information on the transmission order of the sensing signals.

[0308] The wireless sensing procedure can be broadly divided into a setup phase, a negotiation phase, a sensing phase, and a tear-down phase. Each step can be performed in the order described above and can be repeated multiple times in one cycle. The sensing step can include at least one sensing session.

[0309] In the negotiation step, the sensing request frame and the first and second sensing response frames may be exchanged. In the sensing step, the sensing signal may be transmitted, and channel measurement may be performed based on the sensing signal. The sensing step may be torn down if no frame exchange occurs within a time period indicated by timeout information for the sensing step. In the torn down step, negotiated parameter information may be reset, and all sensing sessions of the sensing step may be terminated. To start a sensing session again, the negotiation step must be performed again.

[0310] After the timer according to the timer information for the negotiation step expires, no additional sensing request frame is transmitted by the first STA.

[0311] The role information of the STA can be set to the first or second mode.

[0312] The first mode may include information that the first STA is a transmitter that transmits the sensing signal, and the second and third STAs are receivers that receive the sensing signal and perform channel measurement based on the sensing signal. The second mode may include information that the first STA is the receiver, and the second and third STAs are the transmitters. That is, the roles of the first to third STAs in the sensing step (or sensing session) may be designated based on the first and second modes.

[0313] When the role information of the STA is set to the second mode, the first STA can receive a first sensing signal from the second STA and perform channel measurement based on the first sensing signal, and the first STA can receive a second sensing signal from the third STA and perform channel measurement based on the second sensing signal.

[0314] Furthermore, the role information of the STAs can be utilized together with the STA identifier information. For example, when the role information of the STAs is set to a first mode and the STA identifier information includes only the identifier of the second STA, the first and second STAs can be transmitters, and the third STA can be a receiver. As another example, when the role information of the STAs is set to a second mode and the STA identifier information includes only the identifier of the third STA, the first and third STAs can be receivers, and the second STA can be a transmitter.

[0315] The information on the frequency band to which the sensing signal is allocated may include information on a primary 40 MHz band allocated to the second STA and information on a secondary 40 MHz band allocated to the third STA, wherein the first sensing signal may be received via the primary 40 MHz band and the second sensing signal may be received via the secondary 40 MHz band.

[0316] When the sensing step includes first and second sensing sessions, the first STA may transmit a first sensing start frame to the second and third STAs during the first sensing session, and the first STA may transmit a second sensing start frame to the second and third STAs during the second sensing session.

[0317] If the parameter information is changed in the second sensing session, the second sensing start frame may include a control field for the changed parameter. The control field for the changed parameter may include first and second fields. The first field may include information on whether a changed parameter exists. The second field may include a changed parameter value indicated by the first field.

[0318] The sensing procedure performed during the first sensing session may be performed by the first to third STAs based on the parameter values ​​before being changed, and the sensing procedure performed during the second sensing session may be performed by the first to third STAs based on the changed parameter values.

[0319] For example, the changed parameter is role information of the STA. Assuming that the role information of the STA is set to the second mode in the negotiation step, the first STA may be set as a receiving end, and the second and third STAs may be set as transmitting ends. In this case, during the first sensing session, the second and third STAs may each transmit a sensing signal to the first STA, and the first STA may feed back a value measured based on the sensing signal.

[0320] However, if the role information of the STA is changed to the first mode in the second sensing session, the first STA may be set as a transmitter, and the second and third STAs may be set as receivers. Accordingly, during the second sensing session, the first STA transmits sensing signals to the second and third STAs, and the second and third STAs are role-switched by feeding back values ​​measured based on the sensing signals.

[0321] As another example, the changed parameter is information on a frequency band to which the sensing signal is allocated. If, in the second sensing session, the information on the frequency band to which the sensing signal is allocated is changed to information on a primary 80 MHz band allocated to the second STA and information on a secondary 80 MHz band allocated to the third STA, a first sensing signal transmitted by the second STA may be transmitted via the primary 80 MHz band, and a second sensing signal transmitted by the third STA may be transmitted via the secondary 80 MHz band.

[0322] FIG. 49 is a flowchart showing the procedure by which the sensing responder according to this embodiment performs sensing.

[0323] The example of Figure 49 can be executed in a network environment where a next-generation wireless LAN system (IEEE802.11bf) is supported. The next-generation wireless LAN system is an improved version of the 802.11ad and 802.11ay systems, and can satisfy backward compatibility with the 802.11ad and 802.11ay systems.

[0324] The example of Figure 49 is performed at a second STA, which may correspond to a sensing responder. The first STA of Figure 49 may correspond to a sensing initiator. The third STA of Figure 49 may also correspond to a sensing responder.

[0325] This embodiment proposes a method for determining STAs that will participate in sensing in a wireless LAN system, negotiating parameters to be used for sensing, and executing a sensing procedure based on the negotiated parameters. In particular, this embodiment proposes a method for role negotiation in the negotiation step, parameter negotiation, and parameter change in the sensing step.

[0326] In step S4910, a second STA (station) receives a sensing request frame from the first STA.

[0327] In step S4920, the second STA transmits a first sensing response frame to the first STA. In response to the sensing request frame, a second sensing response frame is transmitted by a third STA.

[0328] The sensing request frame includes STA identifier information and RU (Resource Unit) allocation information. The STA identifier information includes identifiers of the second and third STAs. The RU allocation information includes information on a first RU allocated to the second STA and information on a second RU allocated to the third STA.

[0329] The first sensing response frame is received via the first RU, and the second sensing response frame is received via the second RU. That is, responses to the sensing request frame can be received (simultaneously) by the second and third STAs based on Orthogonal Frequency Division Multiple Access (OFDMA). The sensing request frame can be a (newly defined) trigger frame. If the STA identifier information does not include the identifier of a fourth STA, the first STA does not receive the third sensing response frame from the fourth STA.

[0330] That is, in this embodiment, the sensing request frame indicates the identifier (ID) of the STA receiving the sensing response frame and RU allocation information, and the STA corresponding to the STA identifier can receive the sensing request frame and transmit the sensing response frame through the assigned RU after SIFS.

[0331] The sensing request frame may further include timer information for receiving the sensing response frame. The first and second sensing response frames may be transmitted before a timer according to the timer information expires. After the timer according to the timer information expires, the third sensing response frame is not transmitted. That is, the STA that receives the timer information can know until when the sensing request frame will be transmitted, and can transmit the sensing response frame before the timer expires.

[0332] The sensing request frame may further include parameter information.

[0333] The parameter information may include timer information for the negotiation step, STA role information, timeout information for the sensing step, information on the number of sensing sessions included in the sensing step, information on the first to third STAs, information on the length of the sensing signal, information on the frequency band to which the sensing signal is assigned, information on the type of information to be measured based on the sensing signal, information on the type of the sensing signal, and information on the transmission order of the sensing signals.

[0334] The wireless sensing procedure can be broadly divided into a setup phase, a negotiation phase, a sensing phase, and a tear-down phase. Each step can be performed in the order described above and can be repeated multiple times in one cycle. The sensing step can include at least one sensing session.

[0335] In the negotiation step, the sensing request frame and the first and second sensing response frames may be exchanged. In the sensing step, the sensing signal may be transmitted, and channel measurement may be performed based on the sensing signal. The sensing step may be torn down if no frame exchange occurs within a time period indicated by timeout information for the sensing step. In the torn down step, negotiated parameter information may be reset, and all sensing sessions of the sensing step may be terminated. To start a sensing session again, the negotiation step must be performed again.

[0336] After the timer according to the timer information for the negotiation step expires, no additional sensing request frame is transmitted by the first STA.

[0337] The role information of the STA can be set to the first or second mode.

[0338] The first mode may include information that the first STA is a transmitter that transmits the sensing signal, and the second and third STAs are receivers that receive the sensing signal and perform channel measurement based on the sensing signal. The second mode may include information that the first STA is the receiver, and the second and third STAs are the transmitters. That is, the roles of the first to third STAs in the sensing step (or sensing session) may be designated based on the first and second modes.

[0339] When the role information of the STA is set to the second mode, the first STA can receive a first sensing signal from the second STA and perform channel measurement based on the first sensing signal, and the first STA can receive a second sensing signal from the third STA and perform channel measurement based on the second sensing signal.

[0340] Furthermore, the role information of the STAs can be utilized together with the STA identifier information. For example, when the role information of the STAs is set to a first mode and the STA identifier information includes only the identifier of the second STA, the first and second STAs can be transmitters, and the third STA can be a receiver. As another example, when the role information of the STAs is set to a second mode and the STA identifier information includes only the identifier of the third STA, the first and third STAs can be receivers, and the second STA can be a transmitter.

[0341] The information on the frequency band to which the sensing signal is allocated may include information on a primary 40 MHz band allocated to the second STA and information on a secondary 40 MHz band allocated to the third STA, wherein the first sensing signal may be received via the primary 40 MHz band and the second sensing signal may be received via the secondary 40 MHz band.

[0342] When the sensing step includes first and second sensing sessions, the first STA may transmit a first sensing start frame to the second and third STAs during the first sensing session, and the first STA may transmit a second sensing start frame to the second and third STAs during the second sensing session.

[0343] If the parameter information is changed in the second sensing session, the second sensing start frame may include a control field for the changed parameter. The control field for the changed parameter may include first and second fields. The first field may include information on whether a changed parameter exists. The second field may include a changed parameter value indicated by the first field.

[0344] The sensing procedure performed during the first sensing session may be performed by the first to third STAs based on the parameter values ​​before being changed, and the sensing procedure performed during the second sensing session may be performed by the first to third STAs based on the changed parameter values.

[0345] For example, the changed parameter is role information of the STA. Assuming that the role information of the STA is set to the second mode in the negotiation step, the first STA may be set as a receiving end, and the second and third STAs may be set as transmitting ends. In this case, during the first sensing session, the second and third STAs may each transmit a sensing signal to the first STA, and the first STA may feed back a value measured based on the sensing signal.

[0346] However, if the role information of the STA is changed to the first mode in the second sensing session, the first STA may be set as a transmitter, and the second and third STAs may be set as receivers. Accordingly, during the second sensing session, the first STA transmits sensing signals to the second and third STAs, and the second and third STAs are role-switched by feeding back values ​​measured based on the sensing signals.

[0347] As another example, the changed parameter is information on a frequency band to which the sensing signal is assigned. If, in the second sensing session, the information on the frequency band to which the sensing signal is assigned is changed to information on a primary 80 MHz band assigned to the second STA and information on a secondary 80 MHz band assigned to the third STA, a first sensing signal transmitted by the second STA can be transmitted via the primary 80 MHz band, and a second sensing signal transmitted by the third STA can be transmitted via the secondary 80 MHz band.

[0348] The technical features of the present specification may be applied to various devices and methods. For example, the technical features of the present specification may be implemented / supported by the device of FIG. 1 and / or FIG. 8. For example, the technical features of the present specification may be applied to only a part of FIG. 1 and / or FIG. 8. For example, the technical features of the present specification may be implemented based on the processing chips 114 and 124 of FIG. 1, or based on the processors 111 and 121 and memories 112 and 122 of FIG. 1, or based on the processor 810 and memory 820 of FIG. 8. For example, the device of the present specification broadcasts a sensing request frame, receives a first sensing response frame from a second STA (station), and receives a second sensing response frame from a third STA.

[0349] The technical features of the present specification may be implemented based on a computer readable medium (CRM). For example, the CRM proposed by the present specification is at least one computer readable medium including instructions to be executed by at least one processor.

[0350] The CRM may store instructions for performing operations including broadcasting a sensing request frame, receiving a first sensing response frame from a second STA, and receiving a second sensing response frame from a third STA. The instructions stored in the CRM herein may be executed by at least one processor. The at least one processor associated with the CRM herein may be processors 111 and 121 or processing chips 114 and 124 of FIG. 1, or processor 810 of FIG. 8. Meanwhile, the CRM herein may be memories 112 and 122 of FIG. 1, memory 820 of FIG. 8, or a separate external memory / storage medium / disk.

[0351] The technical features of the present specification described above can be applied to various applications and business models, for example, the technical features described above can be applied to wireless communication in devices that support artificial intelligence (AI).

[0352] Artificial intelligence refers to the field that studies artificial intelligence or the methodologies for creating it, while machine learning refers to the field that defines various problems to be dealt with in the field of artificial intelligence and studies the methodologies for solving them. Machine learning can also be defined as an algorithm that improves its performance for a certain task through continuous experience with that task.

[0353] An artificial neural network (ANN) is a model used in machine learning that is composed of artificial neurons (nodes) that form a network of synaptic connections and has problem-solving capabilities. An artificial neural network is defined by the connection patterns between neurons in different layers, a learning process that updates the model parameters, and an activation function that generates output values.

[0354] An artificial neural network can include an input layer, an output layer, and optionally one or more hidden layers. Each layer contains one or more neurons, and an artificial neural network can include synapses connecting neurons. In an artificial neural network, each neuron can output a function value of an activation function in response to input signals, weights, and biases received via synapses.

[0355] Model parameters are parameters determined through learning, such as synaptic connection weights and neuron biases, while hyperparameters are parameters that must be set before learning in machine learning algorithms, such as the learning rate, number of iterations, mini-batch size, and initialization function.

[0356] The goal of training an artificial neural network is to determine the model parameters that minimize the loss function, which is used as an index to determine the optimal model parameters in the training process of the artificial neural network.

[0357] Depending on the learning method, machine learning can be classified as supervised learning, unsupervised learning, and reinforcement learning.

[0358] Supervised learning is a method of training an artificial neural network when labels for training data are given, and refers to the correct answer (or resulting value) that the artificial neural network needs to infer when training data called labels are input to the artificial neural network. Unsupervised learning is a method of training an artificial neural network when labels for training data are not given. Reinforcement learning is a learning method that trains an agent defined in an environment to select actions or action sequences that maximize cumulative rewards in each state.

[0359] Among artificial neural networks, machine learning implemented as a deep neural network (DNN) with multiple hidden layers is also called deep learning, and deep learning is a part of machine learning. In what follows, machine learning will be used to include deep learning.

[0360] The above-mentioned technical features are also applicable to wireless communication of robots.

[0361] A robot is a machine that automatically processes or operates a given task using its own capabilities. In particular, a robot that has the ability to recognize its environment, make its own decisions, and execute its actions is called an intelligent robot.

[0362] Robots can be classified according to their intended use and field, such as industrial, medical, domestic, and military. Robots have drive units including actuators or motors, allowing them to perform various physical actions such as moving robot joints. Mobile robots also have drive units including wheels, brakes, and propellers, allowing them to move on the ground or fly in the air.

[0363] The technical features described above also apply to devices that support augmented reality.

[0364] Augmented reality is a general term for virtual reality (VR), augmented reality (AR), and mixed reality (MR). VR technology provides real-world objects and backgrounds only as CG images, AR technology provides virtual CG images on top of images of real objects, and MR technology is a computer graphics technology that mixes and combines virtual objects into the real world.

[0365] MR technology is similar to AR technology in that it displays virtual objects together, but the difference is that in AR technology, virtual objects are used to complement each other, while in MR technology, virtual objects are used with equal characteristics.

[0366] XR technology is applied to HMDs (Head-Mount Displays), HUDs (Head-Up Displays), mobile phones, tablet PCs, laptops, desktops, TVs, digital signage, etc., and devices to which XR technology is applied can be called XR devices.

[0367] The claims described herein may be combined in various ways, for example, the technical features of the method claims herein may be combined and implemented in an apparatus, the technical features of the device claims herein may be combined and implemented in a method, the technical features of the method claims herein may be combined with the technical features of the device claims herein may be combined and implemented in an apparatus, and the technical features of the method claims herein may be combined with the technical features of the device claims herein may be combined and implemented in a method.

Claims

1. A method in a wireless local area network (WLAN) system, comprising: a sensing initiator sending a sensing measurement request frame to a sensing responder to establish a sensing measurement session; the sensing initiator receiving a sensing measurement response frame from the sensing responder; The sensing measurement request frame includes a measurement session expiration value, which is a time after which the sensing measurement session will end if there is no frame exchange sequence; the sensing measurement session is terminated after expiration of a sensing measurement session expiration timer; the sensing measurement session expiration timer is set to the measurement session expiration value; The sensing measurement request frame is transmitted together with a measurement session ID (Identifier) ​​corresponding to the sensing measurement session, the measurement session ID is assigned by the sensing initiator to the sensing responder during establishment of the sensing measurement session; The same measurement session ID is assigned to different sensing responders, The measurement session ID is utilized to enable identification.

2. The sensing measurement request frame further includes timer information for receiving the sensing measurement response frame, The sensing measurement response frame is transmitted before a timer of the timer information expires; The method of claim 1 , wherein the sensing measurement response frame is not transmitted after the timer of the timer information expires.

3. The sensing measurement request frame further includes parameter information, The parameter information is timer information for the negotiation step, STA (station) role information, timeout information for the sensing step, Information regarding the number of sensing sessions included in the sensing step; information about the length of the sensing signal; Information about a frequency band to which the sensing signal is assigned; Information regarding the type of information to be measured based on the sensing signal; Information about the type of the sensing signal; and information regarding the transmission order of the sensing signals; In the negotiating step, the sensing measurement request frame and the sensing measurement response frame are exchanged, The method of claim 1 , wherein in the sensing step, the sensing signal is transmitted and a channel measurement is performed based on the sensing signal.

4. The method of claim 3 , wherein after a timer according to the timer information for the negotiation step expires, no additional sensing measurement request frame is transmitted by the sensing initiator.

5. In a sensing initiator in a WLAN (wireless local area network) system, Memory and A transceiver; a processor operatively coupled to the memory and the transceiver; The processor: Sending a sensing measurement request frame to a sensing responder to establish a sensing measurement session; receiving a sensing measurement response frame from the sensing responder; The sensing measurement request frame includes a measurement session expiration value, which is a time after which the sensing measurement session will end if there is no frame exchange sequence; the sensing measurement session is terminated after expiration of a sensing measurement session expiration timer; the sensing measurement session expiration timer is set to the measurement session expiration value; The sensing measurement request frame is transmitted together with a measurement session ID (Identifier) ​​corresponding to the sensing measurement session, the measurement session ID is assigned by the sensing initiator to the sensing responder during establishment of the sensing measurement session; The same measurement session ID is assigned to different sensing responders, The measurement session ID is utilized to enable identification of the sensing initiator.

6. A method in a wireless local area network (WLAN) system, comprising: a sensing responder receiving a sensing measurement request frame from a sensing initiator and establishing a sensing measurement session; the sensing responder sending a sensing measurement response frame to the sensing initiator; The sensing measurement request frame includes a measurement session expiration value, which is a time after which the sensing measurement session will end if there is no frame exchange sequence; the sensing measurement session is terminated after expiration of a sensing measurement session expiration timer; the sensing measurement session expiration timer is set to the measurement session expiration value; The sensing measurement request frame is transmitted together with a measurement session ID (Identifier) ​​corresponding to the sensing measurement session, the measurement session ID is assigned by the sensing initiator to the sensing responder during establishment of the sensing measurement session; The same measurement session ID is assigned to different sensing responders, The measurement session ID is utilized to enable identification.

7. The sensing measurement request frame further includes timer information for receiving the sensing measurement response frame, The sensing measurement response frame is transmitted before a timer of the timer information expires; The method of claim 6 , wherein the sensing measurement response frame is not transmitted after the timer of the timer information expires.

8. The sensing measurement request frame further includes parameter information, The parameter information is timer information for the negotiation step, STA (station) role information, timeout information for the sensing step, Information regarding the number of sensing sessions included in the sensing step; information about the length of the sensing signal; Information about a frequency band to which the sensing signal is assigned; Information regarding the type of information to be measured based on the sensing signal; Information about the type of the sensing signal; and information regarding the transmission order of the sensing signals; In the negotiating step, the sensing measurement request frame and the sensing measurement response frame are exchanged, The method of claim 6 , wherein in the sensing step, the sensing signal is transmitted and a channel measurement is performed based on the sensing signal.

9. The method of claim 8 , wherein after a timer according to the timer information for the negotiation step expires, no additional sensing measurement request frame is transmitted by the sensing initiator.

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