Method and apparatus for performing OBSS probing procedure in wireless LAN system

Abstract

A method and apparatus for performing an OBSS sounding procedure in a wireless LAN system are presented. Specifically, a receiving STA receives a first trigger frame from a first transmitting STA. The receiving STA receives the NDPA frame from the second transmitting STA. The receiving STA receives the NDP frame from the second transmitting STA. The receiving STA transmits a feedback frame to the first transmitting STA or the second transmitting STA based on the NDPA frame and the NDP frame. The first trigger frame contains information about the OAID. The OAID is the information of the second sending STA for identifying the receiving STA. An NDPA frame, an NDP frame, and a feedback frame are transmitted and received based on the OAID.

Description

Technical Field

[0001] This specification relates to techniques for performing an OBSS probe procedure in a wireless LAN system, and more specifically, to methods and apparatus for setting an ID for a non-associated STA to provide feedback on or receive feedback on information related to an OBSS channel. Background Technology

[0002] Wireless local area networks (WLANs) have been improved in various ways. For example, the IEEE 802.11ax standard proposed an improved communication environment using orthogonal frequency division multiple access (OFDMA) and downlink multiple user multiple input multiple output (DLMU MIMO) technologies.

[0003] This specification proposes technical features that can be utilized in new communication standards. For example, a new communication standard could be the currently discussed Extremely High Throughput (EHT) standard. The EHT standard could utilize newly proposed increased bandwidth, enhanced PHY layer Protocol Data Unit (PPDU) structures, enhanced sequencing, Hybrid Automatic Repeat Request (HARQ) schemes, etc. The EHT standard could be referred to as the IEEE 802.11be standard.

[0004] The new WLAN standard allows for the use of an increased number of spatial streams. In this case, it may be necessary to improve the signaling technology in the WLAN system to properly utilize the increased number of spatial streams. Summary of the Invention

[0005] Technical issues

[0006] This specification provides methods and apparatus for performing OBSS detection procedures in wireless LAN systems.

[0007] Technical solution

[0008] The examples in this specification present a method for performing an OBSS probe procedure.

[0009] This implementation can be performed in network environments that support next-generation wireless LAN systems (Ultra-High Reliability (UHR) wireless LAN systems or next-generation Wi-Fi). Next-generation wireless LAN systems are improved versions of the 802.11be system and meet backward compatibility requirements with the 802.11be system.

[0010] This implementation is performed at the receiving STA, which can correspond to a beamforming receiver or at least one station (STA). The transmitting STA can correspond to a beamforming transmitter or an access point (AP).

[0011] This embodiment proposes a method for an OBSS AP to perform an NDP probing procedure against a BSS STA, or for a BSS AP to perform an NDP probing procedure against an OBSS STA. Specifically, this embodiment proposes a method for setting an ID for a non-associated STA to provide feedback on information related to the OBSS channel or to receive feedback on information related to the OBSS channel.

[0012] The receiving station (STA) receives the first trigger frame from the first transmitting STA.

[0013] The receiving STA receives a Null Data Packet Advertisement (NDPA) frame from the second transmitting STA.

[0014] The receiving STA receives NDP frames from the second transmitting STA.

[0015] The receiving STA sends a feedback frame to either the first transmitting STA or the second transmitting STA based on the NDPA frame and the NDP frame.

[0016] The receiving STA is a Basic Service Set (BSS) STA, the first transmitting STA is a BSS AP, and the second transmitting STA is an Overlapping Basic Service Set (OBSS) AP.

[0017] The first trigger frame includes information about the OBSS Association Identifier (OAID). The OAID is used by the second transmitting STA to identify the receiving STA. NDPA frames, NDP frames, and feedback frames are transmitted and received based on the OAID.

[0018] In other words, this embodiment proposes a method for setting OAID to perform a probing process for a receiving STA that is not associated with a second transmitting STA.

[0019] Beneficial effects

[0020] According to the implementation method proposed in this specification, the following effects are achieved: the BSS AP can obtain channel information of the neighboring AP (OBSS AP) of the BSS STA more accurately and quickly (or the OBSS AP can obtain channel information of the neighboring AP (BSS AP) of the OBSS STA), thereby enabling more efficient multi-AP operation (especially coordinated beamforming (C-BF) or joint transmission (J-TX). Attached Figure Description

[0021] Figure 1 Examples of transmitting and / or receiving devices are shown in this specification.

[0022] Figure 2 This is a conceptual diagram illustrating the structure of a wireless local area network (WLAN).

[0023] Figure 3 This illustrates a typical link establishment process.

[0024] Figure 4 An example of multi-link (ML) is shown.

[0025] Figure 5 Examples of Physical Protocol Data Units or Physical Layer (PHY) Protocol Data Units (PPDUs) transmitted / received by the STA of this disclosure are shown.

[0026] Figure 6 This is a diagram illustrating the layout of a resource unit (RU) for a 20MHz PPDU.

[0027] Figure 7 This is a diagram illustrating the layout of a resource unit (RU) for a 40MHz PPDU.

[0028] Figure 8 This is a diagram illustrating the layout of a resource unit (RU) for an 80MHz PPDU.

[0029] Figure 9 The operation related to UL-MU is shown.

[0030] Figure 10 An example of using / supporting / defining a channel within the 2.4 GHz band is shown.

[0031] Figure 11 An example of using / supporting / defining channels within the 5 GHz band is shown.

[0032] Figure 12 An example of using / supporting / defining channels within the 6 GHz band is shown.

[0033] Figure 13 Examples of modified transmitting and / or receiving devices are illustrated in this specification.

[0034] Figure 14 This example illustrates the operation based on the standard STX operation.

[0035] Figure 15 An example of coordinated OFDMA (C-OFDMA) is shown.

[0036] Figure 16 An example of coordinated beamforming (CBF) is shown.

[0037] Figure 17 An example of AP selection is shown.

[0038] Figure 18 An example of JTX / JT is shown.

[0039] Figure 19 An example of an OBSS environment is shown.

[0040] Figure 20 An example of an A control subfield of an HE variant HT control field is shown.

[0041] Figure 21 An example of the control information subfield of the ELA control subfield is shown.

[0042] Figure 22 An example of an A control subfield used for MLA requests / responses is shown.

[0043] Figure 23 Another example of an A control subfield used for MLA requests / responses is shown.

[0044] Figure 24 Another example of an A control subfield used for MLA requests / responses is shown.

[0045] Figure 25 Another example of an A control subfield used for MLA requests / responses is shown.

[0046] Figure 26 This is a diagram illustrating the effects of increasing and decreasing transmit power and sensitivity in a WLAN.

[0047] Figure 27 This is an example of a CS area in a WLAN system.

[0048] Figure 28 This is a graph illustrating OBSS / PD and transmit power adjustment rules.

[0049] Figure 29 An example of the measurement request field format for a beacon request is shown.

[0050] Figure 30 An example of the measurement report field format for a beacon report is shown.

[0051] Figure 31 An example of the trigger frame format is shown.

[0052] Figure 32 An example of the NDP announcement frame format is shown.

[0053] Figure 33 An example of EHT non-TB detection is shown.

[0054] Figure 34 An example of EHT TB detection is shown.

[0055] Figure 35 An example of the NDP probe procedure for obtaining OBSS channel information is shown.

[0056] Figure 36 An example of the NDP probing process for OBSS AP is shown.

[0057] Figure 37 Another example of the NDP probing process for OBSS AP is shown.

[0058] Figure 38 This is a flowchart illustrating the operation of the transmitting device according to this embodiment.

[0059] Figure 39 This is a flowchart illustrating the operation of the receiving device according to this embodiment.

[0060] Figure 40 This is a flowchart illustrating the process of performing OBSS detection for OBSS AP and BSS STA according to this embodiment.

[0061] Figure 41 This is a flowchart illustrating the process of performing OBSS detection for BSS STA and OBSS AP according to this embodiment. Detailed Implementation

[0062] In this disclosure, "A or B" can mean "A only", "B only", or "both A and B". In other words, in this disclosure, "A or B" can be interpreted as "A and / or B". For example, in this disclosure, "A, B or C" can mean "A only", "B only", "C only", or "any combination of A, B, and C".

[0063] As used in this disclosure, a forward slash ( / ) or a comma can mean "and / or". For example, "A / B" can mean "A and / or B". Therefore, "A / B" can mean "A only", "B only", or "both A and B". For example, "A, B, C" can mean "A, B, or C".

[0064] In this disclosure, "at least one of A and B" may mean "only A", "only B" or "both A and B". Furthermore, in this disclosure, the expression "at least one of A or B" or "at least one of A and / or B" may be interpreted as "at least one of A and B".

[0065] Furthermore, the brackets used in this disclosure may mean "for example". Specifically, when indicated as "control information (UHR-signal field)", it may mean that "UHR-signal field" is cited as an example of "control information". In other words, the "control information" of this disclosure is not limited to "UHR-signal field", and "UHR-signal field" may be cited as an example of "control information". Moreover, when indicated as "control information (i.e., UHR-signal field)", it may also mean that "UHR-signal field" is cited as an example of "control information".

[0066] Additionally, the term “a / an” as used in this disclosure may mean “at least one” or “one or more”. Furthermore, terms ending with “(plural form)” may mean “at least one” or “one or more”.

[0067] Furthermore, the expressions “based on”, “on the basis of”, or “according to” used in this disclosure mean “at least partially based on”, and not “based on only”.

[0068] The technical features described individually in a single figure in this disclosure can be implemented individually or simultaneously.

[0069] The following examples of this disclosure can be applied to various wireless communication systems. For example, the following examples of this disclosure can be applied to wireless local area network (WLAN) systems. For example, this disclosure can be applied to the IEEE 802.11a / g / n / ac / ax / be / bn standards. Furthermore, the examples of this disclosure can also be applied to next-generation WLAN standards enhanced with Ultra High Reliability (UHR) standards or IEEE 802.11bn. Furthermore, the examples of this disclosure can also be applied to new WLAN standards enhanced from EHT standards or IEEE 802.11be standards. Furthermore, the examples of this disclosure can be applied to mobile communication systems. For example, it can be applied to mobile communication systems based on Long Term Evolution (LTE) according to the 3rd Generation Partnership Project (3GPP) standards and LTE-based evolution. Furthermore, the examples of this disclosure can be applied to communication systems based on the 5G NR standard of 3GPP standards.

[0070] In the following text, for the purpose of describing the technical features of this disclosure, technical features that can be applied to this disclosure will be described.

[0071] Figure 1 Examples of transmitting and / or receiving devices of this disclosure are shown.

[0072] exist Figure 1 In the example, the various technical features described below can be implemented. Figure 1At least one station (STA) is involved. For example, STA 110 and 120 of this disclosure may also be referred to by various terms such as mobile terminal, wireless device, wireless transceiver unit (WTRU), user equipment (UE), mobile station (MS), mobile subscriber unit, or simply user. STA 110 and 120 of this disclosure may also be referred to by various terms such as network, base station, Node B, access point (AP), repeater, router, relay. STA 110 and 120 of this disclosure may also be referred to by various names such as receiving device, transmitting device, receiving STA, transmitting STA, receiving device, transmitting device, etc.

[0073] For example, STA 110 and 120 can be used as AP or non-AP. That is, STA 110 and 120 of this disclosure can be used as AP and / or non-AP. In this disclosure, AP can be indicated as AP STA.

[0074] The STAs 110 and 120 disclosed herein can also jointly support various communication standards other than the IEEE 802.11 standard. For example, they can support communication standards based on 3GPP standards (e.g., LTE, LTE-A, 5G NR standards). Furthermore, the STAs disclosed herein can be implemented in various devices such as mobile phones, vehicles, and personal computers. In addition, the STAs disclosed herein can support communications for various communication services such as voice calls, video calls, data communications, and autonomous driving.

[0075] The STA 110 and 120 disclosed herein may include a media access control (MAC) conforming to the IEEE 802.11 standard and a physical layer interface for radio media.

[0076] The following will refer to Figure 1 Subgraph (a) describes STA 110 and 120.

[0077] The first STA 110 may include 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 blocks / functions may be implemented by a single chip.

[0078] The transceiver 113 of the first STA performs signal transmission / reception operations. Specifically, it can transmit / receive IEEE 802.11 packets (e.g., IEEE 802.11a / b / g / n / ac / ax / be, etc.).

[0079] For example, the first STA 110 can perform the operations that the AP intends to perform. For example, the AP's processor 111 can receive signals via transceiver 113, process receive (RX) signals, generate transmit (TX) signals, and provide control for signal transmission. The AP's memory 112 can store signals received via transceiver 113 (e.g., RX signals) and can store signals to be transmitted via transceiver 113 (e.g., TX signals).

[0080] For example, the second STA 120 can perform operations that a non-AP STA intends to perform. For example, a non-AP transceiver 123 performs signal transmission / reception operations. Specifically, it can transmit / receive IEEE 802.11 packets (e.g., IEEE 802.11a / b / g / n / ac / ax / be packets, etc.).

[0081] For example, a non-AP STA processor 121 can receive signals via transceiver 123, process RX signals, generate TX signals, and provide control for signal transmission. A non-AP STA memory 122 can store signals received via transceiver 123 (e.g., RX signals) and can store signals to be transmitted via transceiver 123 (e.g., TX signals).

[0082] For example, in the disclosure described below, the operation of a device designated as an AP can be performed in either a first STA 110 or a second STA 120. For instance, if the first STA 110 is an AP, the operation of the device designated as an AP can be controlled by the processor 111 of the first STA 110, and related signals can be transmitted or received via a transceiver 113 controlled by the processor 111 of the first STA 110. Furthermore, control information related to the operation of the AP or the AP's TX / RX signals can be stored in the memory 112 of the first STA 110. Similarly, if the second STA 120 is an AP, the operation of the device designated as an AP can be controlled by the processor 121 of the second STA 120, and related signals can be transmitted or received via a transceiver 123 controlled by the processor 121 of the second STA 120. Furthermore, control information related to the operation of the AP or the AP's TX / RX signals can be stored in the memory 122 of the second STA 120.

[0083] For example, in the disclosure described below, the operation of a device indicated as a non-AP (or user STA) can be performed in either 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 indicated as a non-AP can be controlled by the processor 121 of the second STA 120, and related signals can be transmitted or received via a transceiver 123 controlled by the processor 121 of the second STA 120. Furthermore, control information related to the operation of a non-AP or non-AP TX / RX signals can be 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 indicated as a non-AP can be controlled by the processor 111 of the first STA 110, and related signals can be transmitted or received via a transceiver 113 controlled by the processor 111 of the first STA 110. Furthermore, control information related to the operation of a non-AP or non-AP TX / RX signals can be stored in the memory 112 of the first STA 110.

[0084] In the following description, the device referred to as (transmitting / receiving) STA, first STA, second STA, STA1, STA2, AP, first AP, second AP, AP1, AP2, (transmitting / receiving) terminal, (transmitting / receiving) device, (transmitting / receiving) equipment, network, etc., may refer to... Figure 1 STAs 110 and 120. For example, devices not bearing specific reference numerals and designated as (transmitting / receiving) STA, first STA, second STA, STA1, STA2, AP, first AP, second AP, AP1, AP2, (transmitting / receiving) terminal, (transmitting / receiving) device, (transmitting / receiving) equipment, network, etc., may refer to... Figure 1 STAs 110 and 120. For example, in the following example, the operation of various STA transmit / receive signals (e.g., PPDU) can be... Figure 1 This is performed in transceivers 113 and 123. Furthermore, in the following examples, various STAs can generate TX / RX signals or perform data processing and calculations on TX / RX signals in advance. Figure 1The operations are executed in processors 111 and 121. For example, examples of operations for generating TX / RX signals or pre-performing data processing and calculations may include: 1) operations to determine / obtain / configure / calculate / decode / encode bit information of subfields (SIG, STF, LTF, data) included in the PPDU; 2) operations to determine / configure / obtain time resources or frequency resources (e.g., subcarrier resources) for the subfields (SIG, STF, LTF, data) included in the PPDU; 3) operations to determine / configure / obtain specific sequences (e.g., pilot sequences, STF / LTF sequences, additional sequences applied to SIG) for the subfields (SIG, STF, LTF, data) included in the PPDU; 4) power control operations and / or power saving operations for STA applications; and 5) operations related to the determination / obtaining / configuration / decoding / encoding of ACK signals. Furthermore, in the following examples, various information (e.g., information related to fields / subfields / control fields / parameters / power, etc.) used by various STAs to determine / obtain / configure / calculate / decode / encode TX / RX signals may be stored in... Figure 1 In memory 112 and 122.

[0085] Figure 1 The above-described device / STA in sub-diagram (a) can be modified as follows: Figure 1 As shown in subgraph (b). The following will be based on... Figure 1 Subgraph (b) describes STA 110 and 120 of this disclosure.

[0086] For example, Figure 1 The transceivers 113 and 123 shown in sub-diagram (b) can perform the same functions as described above. Figure 1 The transceiver shown in subgraph (a) has the same function. For example, Figure 1 The processing chips 114 and 124 shown in sub-figure (b) may include processors 111 and 121 and memories 112 and 122. Figure 1 The processors 111 and 121 and the memories 112 and 122 shown in sub-figure (b) can perform the above-described functions. Figure 1 The processors 111 and 121 and the memories 112 and 122 shown in sub-figure (a) have the same function.

[0087] The following descriptions of mobile terminal, wireless device, wireless transceiver unit (WTRU), user equipment (UE), mobile station (MS), mobile subscriber unit, user, subscriber STA, network, base station, node B, access point (AP), repeater, router, relay device, receiving unit, transmitting unit, receiving STA, transmitting STA, receiving device, transmitting device, receiving equipment and / or transmitting equipment may refer to Figure 1The STA 110 and 120 shown in sub-figures (a) / (b), or which may refer to Figure 1 The processing chips 114 and 124 are shown in sub-figure (b). That is, the technical features of this disclosure can... Figure 1 It can be performed in STA110 and 120 as shown in subgraphs (a) / (b), or it can be performed only in... Figure 1 This is executed in the processing chips 114 and 124 shown in sub-figure (b). For example, the technical feature of transmitting control signals by the STA can be understood as: through... Figure 1 Transceivers 113 and 123 are shown in sub-figures (a) / (b) transmitting. Figure 1 The technical features of the control signals generated in processors 111 and 121 are shown in sub-figures (a) / (b). Alternatively, the technical features of the STA transmitting control signals can be understood as: in Figure 1 The technical features of generating control signals to be transmitted to transceivers 113 and 123 in the processing chips 114 and 124 shown in sub-figure (b).

[0088] For example, the technical characteristics of receiving STA control signals can be understood as: by means of Figure 1 The technical features of transceivers 113 and 123 receiving control signals shown in sub-figure (a) are illustrated. Alternatively, the technical features of receiving STA control signals can be understood as: by... Figure 1 Processors 111 and 121 shown in subgraph (a) obtain Figure 1 The technical features of the control signals received in transceivers 113 and 123 shown in sub-figure (a). Alternatively, the technical features of the STA receiving control signals can be understood as: by Figure 1 The processing chips 114 and 124 shown in sub-figure (b) obtain Figure 1 Technical features of the control signals received in transceivers 113 and 123 as shown in sub-figure (b).

[0089] Reference Figure 1 Subgraph (b), software codes 115 and 125 can be included in memories 112 and 122. Software codes 115 and 126 can include instructions for controlling the operation of processors 111 and 121. Software codes 115 and 125 can be included in various programming languages.

[0090] Figure 1 The processors 111 and 121 or processing chips 114 and 124 may include application-specific integrated circuits (ASICs), other chipsets, logic circuits, and / or data processing devices. The processor may be an application processor (AP). For example, Figure 1The processors 111 and 121 or processing chips 114 and 124 may include at least one of a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), and a modem. For example, Figure 1 Processors 111 and 121 or processor chips 114 and 124 may be from Qualcomm. Samsung manufactures the SNAPDRAGON™ series processors. The EXYNOS™ series processors manufactured by Apple Inc. MediaTek manufactures A-series processors. The HELIO™ series processors manufactured by Intel Corporation The ATOM™ series processors manufactured or processors enhanced from these processors.

[0091] In this disclosure, an uplink can refer to a link used for communication from a non-AP STA to an AP STA, and uplink PPDUs / packets / signals, etc., can be transmitted via the uplink. Furthermore, in this disclosure, a downlink can refer to a link used for communication from an AP STA to a non-AP STA, and downlink PPDUs / packets / signals, etc., can be transmitted via the downlink.

[0092] Figure 2 This is a conceptual diagram illustrating a wireless local area network (WLAN) architecture.

[0093] Figure 2 The upper part illustrates the structure of the Infrastructure Basic Services Set (BSS) of the Institute of Electrical and Electronics Engineers (IEEE) 802.11.

[0094] Figure 2 The upper part illustrates the structure of the Infrastructure Basic Services Set (BSS) of the Institute of Electrical and Electronics Engineers (IEEE) 802.11.

[0095] Reference Figure 2 The upper part of the wireless LAN system may include one or more infrastructure BSS200 and 205 (hereinafter referred to as BSS). BSS200 and 205 are collections of APs and STAs (such as access point (AP) 225 and station (STA1) 200-1) that have successfully synchronized to communicate with each other, and are not concepts indicating a specific area. BSS205 may include one or more STAs 205-1 and 205-2 that can join an AP 230.

[0096] BSS may include at least one STA, APs 225 and 230 that provide distribution services, and a distribution system (DS) 210 that connects multiple APs.

[0097] Distribution system 210 can implement an Extended Service Set (ESS) 240 that expands by connecting multiple BSSs 200 and 205. ESS 240 can be used as a term to refer to a network configured by connecting one or more APs 225 or 230 via distribution system 210. APs included in an ESS 240 can have the same Service Set Identifier (SSID).

[0098] Portal 220 can be used as a bridge to connect a wireless LAN network (IEEE 802.11) to another network (e.g., 802.X).

[0099] exist Figure 2 The BSS shown above enables networking between APs 225 and 230, as well as between APs 225 and 230 and STAs 200-1, 205-1, and 205-2. However, even without APs 225 and 230, networking can be configured between STAs to enable communication. Networks that enable communication between STAs even without APs 225 and 230 are defined as Ad-Hoc networks or Independent Basic Service Sets (IBSS).

[0100] Figure 2 The lower part illustrates a conceptual diagram of IBSS.

[0101] Reference Figure 2 The lower part of the IBSS is a BSS operating in Ad-Hoc mode. Since the IBSS does not include access points (APs), there is no centralized management entity performing management functions at the center. That is, in the IBSS, STAs 250-1, 250-2, 250-3, 255-4, and 255-5 are managed in a distributed manner. In the IBSS, all STAs 250-1, 250-2, 250-3, 255-4, and 255-5 can consist of mobile STAs and are not permitted to access the DS to form a self-contained network.

[0102] Figure 3 This illustrates a typical link establishment process.

[0103] In S310, the STA can perform network discovery operations. Network discovery operations can include scanning operations by the STA. That is, in order to access a network, the STA needs to discover the networks it wants to participate in. The process of identifying compatible networks before participating in a wireless network is called scanning. Scanning methods include active scanning and passive scanning.

[0104] Figure 3This illustrates a network discovery operation including an active scanning process. In an active scan, the STA performing the scan sends a probe request frame as it moves to a channel and waits for a response to that probe request frame to identify which APs are present in the vicinity. The responding STA sends a probe response frame in response to the probe request frame. Here, the responding STA could be the STA that sent the last beacon frame in the BSS of the channel being scanned. In the BSS, the AP is the responding STA because it sends the beacon frame. In the IBSS, the responding STA is not fixed because the STAs in the IBSS take turns sending beacon frames. For example, when an STA sends a probe request frame via channel 1 and receives a probe response frame via channel 1, the STA can store the BSS-related information included in the received probe response frame, move to the next channel (e.g., channel 2), and perform a scan in the same way (e.g., sending a probe request and receiving a probe response via channel 2).

[0105] although Figure 3 Although not shown, scanning can also be performed using a passive scanning method. In passive scanning, the STA performing the scan can wait for beacon frames while moving to a channel. Beacon frames are one of the management frames in IEEE 802.11 and are periodically sent to indicate the presence of a wireless network, enabling the STA performing the scan to find and join that network. In a BSS, the AP is responsible for periodically sending beacon frames. In an IBSS, STAs in the IBSS take turns sending beacon frames. Upon receiving a beacon frame, the STA performing the scan stores the BSS information included in the beacon frame and records the beacon frame information for each channel while moving to another channel. STAs that have received beacon frames can store the BSS-related information included in the received beacon frames, can move to the next channel, and can perform scanning on the next channel using the same method.

[0106] After discovering the network, the STA can perform an authentication process in S320. This authentication process can be referred to as the first authentication process to clearly distinguish it from the security establishment operations in S340 that follow. The authentication process in S320 may include the STA sending an authentication request frame to the AP, and the AP sending an authentication response frame to the STA in response. The authentication frame used for the authentication request / response is a management frame.

[0107] An authentication frame may include information about the authentication algorithm number, authentication transaction sequence number, status code, challenge text, robust secure network (RSN), and finite cyclic group.

[0108] The STA can send an authentication request frame to the AP. The AP can determine whether to allow the STA's authentication based on the information included in the received authentication request frame. The AP can then provide the authentication result to the STA via an authentication response frame.

[0109] After successful authentication, the STA can perform the association process in S330. The association process includes the STA sending an association request frame to the AP, and the AP responding by sending an association response frame to the STA. The association request frame may include information such as various capabilities, beacon listening interval, service set identifier (SSID), supported rates, supported channels, RSN, mobility domain, supported operation categories, traffic indication map (TIM) broadcast request, and interoperability service capabilities. The association response frame may include information such as various capabilities, status code, association ID (AID), supported rates, enhanced distributed channel access (EDCA) parameter set, received channel power indicator (RCPI), received signal-to-noise ratio indicator (RSNI), mobility domain, timeout interval (association recovery time), overlapping BSS scan parameters, TIM broadcast response, and QoS mapping.

[0110] In the S340, the STA can perform a secure establishment process. This secure establishment process in the S340 can include, for example, establishing a private key through a four-way handshake via an Extensible Authentication Protocol over LAN (EAPOL) frame.

[0111] Figure 4 An example of multi-link (ML) is shown.

[0112] like Figure 4 As shown, multiple multi-link devices (MLDs) can communicate via a remote link. MLDs can be classified as AP MLDs, which include multiple AP STAs, and non-AP MLDs, which include multiple non-AP STAs. That is, an AP MLD may include affiliated APs (i.e., AP STAs), and a non-AP MLD may include affiliated STAs (i.e., non-AP STAs or user STAs).

[0113] A multi-link system can include a first link and a second link, and different channel / sub-channel / frequency resources can be allocated to the first link and the second link. The first and second multi-links can be identified by a 4-bit (or other n-bit) link ID. The first and second links can be configured in the same 2.4 GHz, 5 GHz, or 6 GHz frequency band. Alternatively, the first and second links can be configured in different frequency bands.

[0114] Figure 4 The AP MLD includes three affiliated APs. Figure 4In the example, AP1 can operate in the 2.4 GHz band, AP2 can operate in the 5 GHz band, and AP3 can operate in the 6 GHz band. Figure 4 In the example, the first link operated by AP1 and non-AP1 can be defined as a channel / sub-channel / frequency resource within the 2.4 GHz band. Furthermore, in Figure 4 In the example, the second link operated by AP2 and non-AP2 can be defined as a channel / subchannel / frequency resource within the 5GHz band. Furthermore, in Figure 4 In the example, the third link in which AP3 and non-AP3 operate can be defined as a channel / subchannel / frequency resource within the 6GHz band.

[0115] exist Figure 4 In the example, AP1 can initiate the multi-link establishment process (ML establishment process) by sending an association request frame to a non-AP STA1. Figure 4 In the example, a non-AP STA1 can send an association response frame in response to an association request frame. Figure 4 Each AP shown (e.g., AP1 / 2 / 3) can be associated with Figure 1 and / or Figure 2 The AP shown is the same, and Figure 4 Each non-AP shown (e.g., non-AP1 / 2 / 3) can be associated with Figure 1 and / or Figure 2 The STAs shown are the same (i.e., user STAs or non-AP STAs).

[0116] The specific features of this disclosure are not limited to Figure 4 The specific characteristics include the ability to define the number of links in various ways, and to define multiple links in various ways within at least one frequency band.

[0117] Figure 5 Examples of Physical Protocol Data Units or Physical Layer (PHY) Protocol Data Units (PPDUs) transmitted / received by a STA according to this disclosure are shown.

[0118] The STA (e.g., AP STA, non-AP STA, AP MLD, non-AP MLD) disclosed herein can send and / or receive. Figure 5 The PPDU described in this disclosure may have, for example, Figure 5 The structure is described herein. Furthermore, the PPDU described in this disclosure may be referred to by various names such as transmit PPDU, receive PPDU, first type, or Nth type PPDU. The PPDU described in this disclosure can be used in WLAN systems defined according to IEEE 802.11bn and / or next-generation WLAN systems that improve upon IEEE 802.11bn.

[0119] Figure 5 The PPDU can be associated with various PPDU types used in the UHR system. For example, Figure 5 Examples can be used for at least one of the following modes related to channel detection: single-user (SU) mode / type / transmission, multi-user (MU) mode / type / transmission, and null packet (NDP) mode / type / transmission. For example, if Figure 5 If the example is related to NDP, the data fields shown can be omitted. Figure 5 The PPDU is used in trigger-based (TB) mode, then Figure 6 The UHR-SIG can be omitted. In other words, a STA that has received a trigger frame for uplink-MU (UL-MU) communication can send a signal in... Figure 5 The UHR-SIG PPDU is omitted in the example.

[0120] exist Figure 5 In this context, L-STF or UHR-LTF can be referred to as a preamble or physical preamble, and can be generated / transmitted / received / acquired / decoded at the physical layer (including in the transmit / receive STA).

[0121] Figure 5 Each block shown can be referred to as a field / subfield / signal, etc. The names of these fields / subfields / signals can be, for example... Figure 5 The examples shown are: Traditional Short Training Field (L-STF), Traditional Long Training Field (L-LTF), Traditional Signal (L-SIG), Repeated L-SIG (RL-SIG), Universal Signal (U-SIG), and UHR Signal (UHR-SIG).

[0122] Figure 5 The subcarrier spacing of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and UHR-SIG fields can be determined to be 312.5 kHz, and the subcarrier spacing of the UHR-STF, UHR-LTF, and data fields can be determined to be 78.125 kHz. In other words, the tone index (or subcarrier index) of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and UHR-SIG fields can be represented in units of 312.5 kHz, and the tone index (or subcarrier index) of the UHR-STF, UHR-LTF, and data fields can be represented in units of 78.125 kHz.

[0123] exist Figure 5 In the PPDU, the L-LTF and L-STF can be the same as those in the regular fields (e.g., non-HT LTF and non-HT STF as defined in the regular WLAN standard).

[0124] Figure 5 The L-SIG field can include, for example, 24 bits of bit information. For instance, the 24 bits could include a 4-bit rate field, a 1-bit reserved bit, a 12-bit length field, a 1-bit parity bit, and a 6-bit tail bit. For instance, the 12-bit length field could include information related to the length or duration of the PPDU. For instance, the 12-bit length field could be determined based on the type of PPDU. For instance, when the PPDU is a Non-High Throughput (HT), High Throughput (HT), Very High Throughput (VHT) PPDU, Extremely High Throughput (EHT) PPDU, or UHR PPDU, the value of the length field could be a multiple of 3. For instance, when the PPDU is an HE PPDU, the value of the length field could be a multiple of 3 + 1 or a multiple of 3 + 2. In other words, for non-HT, HT, VHT, EHT, or UHR PPDUs, the length field value can be determined as a multiple of 3. For high-efficiency (HE) PPDUs, the length field value can be determined as either a multiple of 3 + 1 or a multiple of 3 + 2. In other words, the LENGTH field in a UHR PPDU is set to a value that satisfies the condition that LENGTH divided by 3 leaves a remainder of zero.

[0125] For example, a (non-AP and AP) STA can apply BCC encoding to the 24 bits of information in the L-SIG field at half the coding rate. The transmitting STA then obtains 48 bits of BCC encoded bits. BPSK modulation can be applied to these 48 encoded bits to generate 48 BPSK symbols. The transmitting STA can map these 48 BPSK symbols to positions other than the pilot subcarriers {subcarrier indices -21, -7, +7, +21} and the DC subcarrier {subcarrier index 0}. As a result, the 48 BPSK symbols can be mapped to subcarrier indices -26 to -22, -20 to -8, -6 to -1, +1 to +6, +8 to +20, and +22 to +26. The transmitting STA can additionally map the signal {-1, -1, -1, 1} to subcarrier indices {-28, -27, +27, +28}. The above signals can be used for channel estimation in the frequency domain corresponding to {-28, -27, +27, +28}.

[0126] For example, a (non-AP and AP) STA can generate an RL-SIG in the same way as the L-SIG. BPSK modulation can be applied to the RL-SIG. The (non-AP and AP) STA can determine whether an RX PPDU is an HE PPDU, EHT PPDU, or UHR PPDU based on the presence of the RL-SIG. In other words, if the RL-SIG is present, the receiving (non-AP and AP) STA can know that the received PPDU is one of an HE PPDU, EHT PPDU, or UHR PPDU. In other words, if the RL-SIG is not present, the receiving (non-AP and AP) STA can know that the received PPDU is one of a non-HT PPDU, HT PPDU, or VHT PPDU. In other words, the RL-SIG field is a repetition of the L-SIG field and is used to distinguish UHR PPDUs from non-HT PPDUs, HT PPDUs, and VHT PPDUs.

[0127] The universal SIG (U-SIG) can be inserted in Figure 6 Following RL-SIG, U-SIG can be referred to by various terms such as First SIG Field, First SIG, First Type SIG, Control Signal, Control Signal Field, First (Type) Control Signal, Common Control Field, Common Control Signal, etc.

[0128] U-SIG can include N bits of information and may include information identifying the type of EHT PPDU. For example, U-SIG can be configured based on two symbols (e.g., two consecutive OFDM symbols). Each symbol for U-SIG (e.g., an OFDM symbol) can have a duration of 4 µs. Each symbol of U-SIG can be used to transmit 26 bits of information. For example, each symbol of U-SIG can be transmitted / received based on 52 data tones and 4 pilot tones.

[0129] For example, A bits of information (e.g., 52 uncoded bits) can be transmitted via U-SIG. The first symbol of U-SIG can transmit the first X bits of the A bits (e.g., 26 uncoded bits), and the second symbol of U-SIG can transmit the remaining Y bits of the A bits (e.g., 26 uncoded bits). For example, the transmitting STA can obtain the 26 uncoded bits included in each U-SIG symbol. The transmitting STA can perform convolutional coding (i.e., BCC coding) at a rate of R = 1 / 2 to generate 52 coded bits, and can perform interleaving on the 52 coded bits. The transmitting STA can perform BPSK modulation on the interleaved 52 coded bits to generate 52 BPSK symbols to be allocated to each U-SIG symbol. A U-SIG symbol can be transmitted based on 65 tones (subcarriers) from subcarrier index -28 to subcarrier index +28 (excluding DC index 0). The 52 BPSK symbols generated by the transmitting STA can be transmitted based on the remaining tones (subcarriers) other than the pilot tones (i.e., tones -21, -7, +7, +21).

[0130] For example, the A-bit information generated by U-SIG (e.g., 52 uncoded bits) may include a CRC field (e.g., a 4-bit field) and a tail field (e.g., a 6-bit field). The CRC and tail fields can be sent via the second symbol of U-SIG. The CRC field can be generated based on the 26 bits allocated to the first symbol of U-SIG and the remaining 16 bits in the second symbol excluding the CRC / tail field, and can be generated based on a conventional CRC calculation algorithm. Furthermore, the tail field can be used to terminate the trellis diagram of the convolutional decoder and can be set to, for example, "000000".

[0131] The A-bit information (e.g., 52 uncoded bits) sent via U-SIG (or the U-SIG field) can be divided into version-independent bits and version-dependent bits. For example, version-independent bits can have a fixed or variable size. For example, version-independent bits can be assigned only to the first symbol of U-SIG, or version-independent bits can be assigned to both the first and second symbols of U-SIG. For example, version-independent bits and version-dependent bits can be referred to by various terms such as first control bit, second control bit, etc.

[0132] For example, the version-independent bits of the U-SIG may include a 3-bit PHY version identifier. For example, the 3-bit PHY version identifier may include information related to the PHY version of the TX / RX PPDU. For example, the first value of the 3-bit PHY version identifier (e.g., a 000 value) may indicate that the TX / RX PPDU is an EHT PPDU. Furthermore, the second value of the 3-bit PHY version identifier (e.g., a 001 value) may indicate that the TX / RX PPDU is a UHR PPDU.

[0133] In other words, when an (AP / non-AP) STA sends an EHT PPDU, the 3-bit PHY version identifier can be set to a first value, and when an (AP / non-AP) STA sends a UHR PPDU, the 3-bit PHY version identifier can be set to a second value. In other words, the receiving (AP / non-AP) STA can determine that the received PPDU is an EHT PPDU based on the first value of the PHY version identifier, and can determine that the received PPDU is a UHR PPDU based on the second value of the PHY version identifier.

[0134] For example, the version-independent bits of U-SIG may include a 1-bit UL / DL flag field. The first value of the 1-bit UL / DL flag field is related to UL communication, and the second value of the UL / DL flag field is related to DL communication.

[0135] For example, the version-independent bits of U-SIG can include information related to the transmission opportunity (TXOP) length and information related to the BSS color ID.

[0136] For example, if a UHR PPDU is classified into various types (e.g., types related to SU transmission (based on UL or DL), types related to DL transmission, types related to NDP transmission, types related to DL non-MU-MIMO, types related to DL MU-MIMO, types related to multi-AP operation, types related to Co-BF beamforming (Co-BF), spatial reuse (SR), types related to Co-OFDMA (C-OFDMA), and types related to Co-TDMA (Co-TDMA), then information about the UHR PPDU type (e.g., 2-bit or 3-bit information) can be included in the version-related bits of the U-SIG.

[0137] For example, U-SIG may include: 1) a bandwidth field including information related to bandwidth; 2) a field including information related to the modulation and coding scheme (MCS) applied to UHR-SIG; 3) an indication field including information about whether a dual-carrier modulation (DCM) scheme is applied to UHR-SIG; 4) a field including information related to the number of symbols used for UHR-SIG; 5) a field including information about whether UHR-SIG is generated across the entire frequency band; 6) a field including information related to the type of UHR-LTF / STF; and 7) information related to fields indicating the length of UHR-LTF and the length of CP.

[0138] Can to Figure 5 The PPDU uses preamble puncturing. Preamble puncturing means applying puncturing to a portion of the entire frequency band (e.g., the secondary 20MHz band). For example, when transmitting an 80MHz PPDU, the STA can apply puncturing to the secondary 20MHz band outside the 80MHz band, and can transmit the PPDU only through the primary 20MHz band and the secondary 40MHz band.

[0139] For example, the preamble punching pattern can be pre-configured. For example, when applying the first punching pattern, punching can be applied only to the secondary 20MHz band within the 80MHz band. For example, when applying the second punching pattern, punching can be applied only to either of the two secondary 20MHz bands included in the secondary 40MHz band within the 80MHz band. For example, when applying the third punching pattern, punching can be applied only to the secondary 20MHz bands included in the primary 80MHz band within the 160MHz band (or 80MHz+80MHz band). For example, when applying the fourth punching pattern, if the primary 40MHz band included in the 80MHz band within the 160MHz band (or 80MHz+80MHz band) exists, punching can be applied to at least one 20MHz channel that does not belong to the primary 40MHz band.

[0140] Information related to preamble puncturing applied to the PPDU can be included in U-SIG and / or UHR-SIG. For example, the first field of U-SIG may include information related to continuous bandwidth, and the second field of U-SIG may include information related to preamble puncturing applied to the PPDU.

[0141] For example, U-SIG and UHR-SIG can include information related to preamble puncturing based on the following method. When the bandwidth of the PPDU exceeds 80MHz, U-SIG can be configured individually in 80MHz units. For example, when the bandwidth of the PPDU is 160MHz, the PPDU can include a first U-SIG for a first 80MHz band and a second U-SIG for a second 80MHz band. In this case, the first field of the first U-SIG can include information related to the 160MHz bandwidth, and the second field of the first U-SIG can include information related to preamble puncturing applied to the first 80MHz band (i.e., information related to the preamble puncturing pattern). Furthermore, the first field of the second U-SIG can include information related to the 160MHz bandwidth, and the second field of the second U-SIG can include information related to preamble puncturing applied to the second 80MHz band (i.e., information related to the preamble puncturing pattern). Furthermore, the UHR-SIG adjacent to the first U-SIG may include information related to preamble puncturing applied to the second 80MHz band (i.e., information related to the preamble puncturing pattern), and the UHR-SIG adjacent to the second U-SIG may include information related to preamble puncturing applied to the first 80MHz band (i.e., information related to the preamble puncturing pattern).

[0142] Additionally or alternatively, U-SIG and UHR-SIG may include information related to preamble puncturing based on the following methods: U-SIG may include information related to preamble puncturing for all frequency bands (i.e., information related to the preamble puncturing pattern). That is, UHR-SIG may not include information related to preamble puncturing, and only U-SIG may include information related to preamble puncturing (i.e., information related to the preamble puncturing pattern).

[0143] U-SIGs can be configured in 20MHz units. For example, when configuring an 80MHz PPDU, U-SIGs can be duplicated. That is, an 80MHz PPDU can include four identical U-SIGs. PPDUs with bandwidths exceeding 80MHz can include different U-SIGs.

[0144] Figure 5 The UHR-SIG can include control information for receiving STA data. The UHR-SIG can be transmitted via at least one symbol, and a symbol can be 4 µs long. Information related to the number of symbols used for the UHR-SIG can be included in the U-SIG.

[0145] UHR-SIG provides additional signals to the U-SIG field, enabling the STA to interpret / decode the UHR PPDU. The UHR-SIG field may include U-SIG overflow bits that are common to all users. Furthermore, the UHR-SIG field includes resource allocation information, allowing the STA to locate resources used in fields including the data field / UHR-STF / UHR-LTF (i.e., the UHR modulation field of the UHR PPDU).

[0146] Figure 5 The frequency resources of the UHR-LTF, UHR-STF, and data fields shown can be determined based on RUs (Resource Units) defined by multiple subcarriers / tones. That is, the UHR-LTF, UHR-STF, and data fields of this disclosure can be transmitted / received through RUs (Resource Units) defined by multiple subcarriers / tones.

[0147] Figure 6 This is a diagram illustrating the layout of a resource unit (RU) for a 20MHz PPDU. That is, the UHR-LTF, UHR-STF, and / or data fields included in a 20MHz PPDU can be... Figure 6 Use at least one of the various RUs defined in the code to send / receive.

[0148] like Figure 6 As shown at the top, 26 units (i.e., units corresponding to 26 tones) can be arranged. Six tones in the leftmost band of the 20MHz band can be used for band protection, and five tones in the rightmost band of the 20MHz band can be used for band protection. Furthermore, seven DC tones can be inserted in the center band (i.e., the DC band), and 26 units corresponding to 13 tones each on the left and right sides of the DC band can be arranged. Units 26, 52, and 106 can be allocated to other bands. Each unit can be allocated to a receiving STA, i.e., a user.

[0149] also, Figure 6 The RU layout in [the code] can be used not only for multi-user (MU) but also for single-user (SU), in which case, such as... Figure 6 As shown at the bottom, a 242-unit can be used, and three DC tones can be inserted.

[0150] although Figure 6Various sizes of RUs, namely 26-RU, 52-RU, 106-RU, and 242-RU, have been proposed, but the specific size of the RU can be extended or increased. Therefore, this embodiment is not limited to a specific size of each RU (i.e., the corresponding number of tones). In this specification, N-RU can be represented as N-tone RU, etc. For example, 26-RU can be represented as 26-tone RU.

[0151] Figure 7 This is a diagram illustrating the layout of a resource unit (RU) for a 40MHz PPDU.

[0152] With the use of RUs of various sizes Figure 6 Similarly, in Figure 7 Examples of frequencies that can be used include 26-RU, 52-RU, 106-RU, 242-RU, and 484-RU. Additionally, five DC tones can be inserted at the center frequency, twelve tones can be used for guard bands in the leftmost band of the 40MHz band, and eleven tones can be used for guard bands in the rightmost band of the 40MHz band.

[0153] like Figure 7 As shown, when the RU layout is used for a single user, a 484-RU can be used. The specific number of RUs can be determined by... Figure 6 Change similarly.

[0154] Figure 8 This is a diagram illustrating the layout of a resource element (RU) for an 80MHz PPDU. The layout of the resource element (RU) used in this specification can be changed. For example, the layout of the resource element (RU) used in the 80MHz band can be changed.

[0155] Figure 9 Operations related to the UL-MU are illustrated. As shown, a transmitting STA (e.g., an AP) can perform channel access through contention (i.e., backoff operation) and transmit a trigger frame (930). That is, the transmitting STA (e.g., an AP) can transmit a PPDU including the trigger frame (930). When the PPDU including the trigger frame is received, a TB (trigger-based) PPDU is transmitted after a delay of SIFS.

[0156] TB PPDUs (941, 942) are transmitted simultaneously and can be sent from multiple STAs (e.g., user STAs) whose AID is indicated in the trigger frame (930). Acknowledgment (ACK) frames (950) for TB PPDUs can be implemented in various forms.

[0157] Figure 10 An example of using / supporting / defining a channel within the 2.4 GHz band is shown.

[0158] The 2.4 GHz band can also be referred to by other names such as "first band". Furthermore, the 2.4 GHz band can refer to the frequency range in which channels with a center frequency close to 2.4 GHz are used / supported / defined (e.g., channels with a center frequency between 2.4 GHz and 2.5 GHz).

[0159] The 2.4 GHz band can include multiple 20 MHz channels. Each 20 MHz channel within the 2.4 GHz band can have multiple channel indices (e.g., indices 1 to 14). For example, the center frequency of a 20 MHz channel assigned channel index 1 could be 2.412 GHz, the center frequency of a 20 MHz channel assigned channel index 2 could be 2.417 GHz, and the center frequency of a 20 MHz channel assigned channel index N could be (2.407 + 0.005 * N) GHz. Channel indices can be referred to by various names such as channel numbers. The specific values ​​of the channel index and center frequency can be changed.

[0160] Figure 10 Four channels within a 2.4 GHz frequency band are illustrated exemplarily. The first frequency region (1010) through the fourth frequency region (1040) shown may each include one channel. For example, the first frequency region (1010) may include channel 1 (a 20 MHz channel with index 1). In this case, the center frequency of channel 1 may be set to 2412 MHz. The second frequency region (1020) may include channel 6. In this case, the center frequency of channel 6 may be set to 2437 MHz. The third frequency region (1030) may include channel 11. In this case, the center frequency of channel 11 may be set to 2462 MHz. The fourth frequency region (1040) may include channel 14. In this case, the center frequency of channel 14 may be set to 2484 MHz.

[0161] Figure 11 An example of using / supporting / defining channels within the 5 GHz band is shown.

[0162] The 5GHz band can be referred to by other names such as the second band / band. A 5GHz band can refer to a frequency range that uses / supports / defines channels with a center frequency greater than or equal to 5GHz and less than 6GHz (or less than 5.9GHz). Alternatively, a 5GHz band can include multiple channels between 4.5GHz and 5.5GHz. Figure 11 The specific figures shown may be subject to change.

[0163] Multiple channels within the 5 GHz band include the unlicensed National Information Infrastructure (UNII)-1, UNII-2, UNII-3, and ISM. UNII-1 may be referred to as the UNII Low Band. UNII-2 may include frequency ranges referred to as the UNII Mid Band and UNII-2 Extended Band. UNII-3 may be referred to as the UNII High Band.

[0164] Within the 5 GHz band, multiple channels can be configured, and the bandwidth of each channel can be configured in various ways, such as 20 MHz, 40 MHz, 80 MHz, or 160 MHz. For example, the 5170 MHz to 5330 MHz frequency domain / range within UNII-1 and UNII-2 can be divided into eight 20 MHz channels. The 5170 MHz to 5330 MHz frequency domain / range can be divided into four channels using a 40 MHz frequency domain. The 5170 MHz to 5330 MHz frequency domain / range can be divided into two channels using an 80 MHz frequency domain. Alternatively, the 5170 MHz to 5330 MHz frequency domain / range can be divided into one channel using a 160 MHz frequency domain.

[0165] Figure 12 An example of using / supporting / defining channels within the 6 GHz band is shown.

[0166] The 6GHz band can be referred to by other names such as the third band / band. The 6GHz band can refer to the frequency range that uses, supports, and defines channels with center frequencies higher than 5.9GHz. Figure 12 The specific values ​​shown can be changed.

[0167] For example, Figure 12 The 20MHz channel can be defined as starting from 5.940GHz. Specifically, Figure 12 The leftmost channel in a 20MHz channel can have an index (or channel index, channel number, etc.) of 1 and be assigned a center frequency of 5.945GHz. In other words, the center frequency of channel index N can be determined as (5.940 + 0.005 * N) GHz.

[0168] therefore, Figure 12The index (or channel number) of the 20MHz channel can be 1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57, 61, 65, 69, 73, 77, 81, 85, 89, 93, 97, 101, 105, 109, 113, 117, 121, 125, 129, 133, 137, 141, 145, 149, 153, 157, 161, 165, 169, 173, 177, 181, 185, 189, 193, 197, 201, 205, 209, 213, 217, 221, 225, 229, 233. Furthermore, according to the above rule of (5.940 + 0.005 * N) GHz, Figure 12 The index of the 40MHz channel can be 3, 11, 19, 27, 35, 43, 51, 59, 67, 75, 83, 91, 99, 107, 115, 123, 131, 139, 147, 155, 163, 171, 179, 187, 195, 203, 211, 219, 227.

[0169] Figure 13 Examples of modifications to the transmitting and / or receiving apparatus of this disclosure are shown.

[0170] Figures 1 to 4 The apparatus shown (e.g., AP STA, non-AP STA) can be modified as follows: Figure 13 As shown. Figure 13 The transceiver 630 can be used with Figure 1 The transceivers 113 and 123 are the same. Figure 13 The transceiver 630 may include a receiver and a transmitter.

[0171] Figure 13 The processor 610 can be with Figure 1 The processors 111 and 121 are the same. Alternatively, Figure 13 The processor 610 can be with Figure 1 The processing chips 114 and 124 are the same.

[0172] Figure 13 The memory 150 can be with Figure 1 The memory modules 112 and 122 are identical. Alternatively, Figure 13 The memory 150 can be with Figure 1 The memory 112 and 122 are different independent external memories.

[0173] Reference Figure 13The power management module 611 manages the power supplied to the processor 610 and / or transceiver 630. The battery 612 supplies power to the power management module 611. The display 613 outputs the results processed by the processor 610. The keypad 614 receives input to be used by the processor 610. The keypad 614 can be displayed on the display 613. The SIM card 615 can be an integrated circuit for securely storing the International Mobile Subscriber Identity (IMSI) and its associated keys, which are used to identify and authenticate subscribers in mobile devices such as mobile phones and computers.

[0174] Reference Figure 13 The speaker (640) can output the sound-related results processed by the processor 610. The microphone (641) can receive sound-related inputs to be used by the processor 610.

[0175] The following describes the multi-AP operation applied to this manual.

[0176] Multi-AP operation refers to communication techniques involving multiple APs in a WLAN. For example, multi-AP operation can refer to the transmission and reception of information between one or more APs and one or more STAs. In contrast to multi-AP operation, existing technologies may use various terms such as STX (Single Transmission). For example, STX operation can refer to a method of communication between a BSS AP and a BSS STA. When communication is performed based on STX operation, interference with neighboring APs (e.g., APs located in overlapping BSSs) may occur. This interference can lead to degraded transmission and reception performance for cell-edge users (e.g., non-AP STAs located at the edge of the BSS).

[0177] Figure 14 The following example illustrates the operation based on standard STX procedures. As shown in the figure, adjacent AP1 and AP2 may cause interference between the STA and the AP.

[0178] To improve STX operation, a new multi-AP operation is proposed. This multi-AP operation can be based on techniques to reduce various interferences (such as inter-symbol interference (ISI)) by coordinating with neighboring APs (e.g., APs located in overlapping BSSs).

[0179] exist Figure 14 In this context, STA1 and AP1 can be included in the BSS, and STA2 and AP2 can be included in the OBSS (Overlapping Basic Service Set). That is, STA2 can be an STA that is not associated with AP1, and STA1 can be an STA that is not associated with AP2.

[0180] For example, multi-AP operation can be categorized into various technologies / types / formats / protocols, etc. For instance, multi-AP operation may include coordinated TDMA (C-TDMA) that differentiates radio resources allocated to multiple APs based on the time axis (time domain). Alternatively, multi-AP operation may include coordinated OFDMA (C-OFDMA) that differentiates radio resources allocated to multiple APs based on the frequency axis (time domain). Alternatively, multi-AP operation may include coordinated spatial reuse (C-SR) that applies spatial reuse (SR) to at least one AP. Alternatively, multi-AP operation may include coordinated beamforming (CBF) / nulling that zeros and transmits interference generated from neighbors (e.g., adjacent AP / STA and / or OBSS AP / OBSS STA). Alternatively, multi-AP operation may include AP selection, where the AP with good channel conditions among the neighboring APs (e.g., at least one AP located within a BSS or OBSS and with good channel conditions) transmits. Additionally or alternatively, multi-AP operation may include Joint Transmission (JTX) or JT, in which multiple APs (e.g., multiple APs included in the same BSS / OBSS, or multiple APs included in different BSS / OBSS) coordinate to perform simultaneous transmission and reception, and JTX / JT may be implemented based on joint beamforming or joint MU-MIMO.

[0181] Figure 15 An example of coordinated OFDMA (C-OFDMA) is illustrated. AP1 can transmit PPDU / signals to STA1, and AP2 can transmit PPDU / signals to STA2. Transmissions from AP1 and from AP2 can be performed in the same / overlapping time intervals. Transmissions from AP1 to STA1 can be performed based on a first frequency band, and transmissions from AP2 to STA2 can be performed based on a second frequency band different from the first frequency band. For example, in... Figure 15 In this context, STA1 and AP1 can be included in the BSS, and STA2 and AP2 can be included in the OBSS. That is, STA2 can be an STA that is not associated with AP1, and STA1 can be an STA that is not associated with AP2.

[0182] although Figure 15 Not illustrated, but examples of coordinated TDMA (C-TDMA) are also possible. For instance, the acquired TXOP can be divided into specific time units (e.g., time slots), and the divided time slots can be sequentially assigned to multiple different APs.

[0183] The C-OFDMA example described above can be further modified as follows. For example, an AP that has acquired a TXOP (e.g., AP1) can share frequency resources with at least one neighboring AP (e.g., AP2 in the BSS / OBSS). For example, the shared frequency resources can be defined based on resource units (RUs) or sub-channels. For example, for flexibility, frequency resources can be shared from AP1 to AP2 in units of 20 / 40 / 80MHz sub-channels or 242 / 484 / 996-tone RUs.

[0184] AP1 performing C-OFDMA can act as a shared AP or a primary AP. That is, AP1 can request at least one neighboring AP (e.g., AP2 in the BSS / OBSS) to report information about channel and / or buffer status. Based on this, AP1 can obtain a TXOP and, for all or part of the time interval associated with that TXOP, share a portion of frequency resources (e.g., a 20MHz subchannel or a specific-sized RU) with at least one nearby AP (e.g., AP2 present in the BSS / OBSS).

[0185] Figure 16 An example of coordinated beamforming (CBF) is illustrated. AP1 can transmit PPDU / signal to STA1, and AP2 can transmit PPDU / signal to STA2. Transmissions from AP1 and AP2 can be performed in the same / overlapping time intervals. Transmissions from AP1 and AP2 can be performed in the same / overlapping frequency bands. To reduce interference from AP1 to STA2, AP1 can perform nulling / beamforming towards STA2, and to reduce interference from AP2 to STA1, AP2 can perform nulling / beamforming towards STA1. For example, this nulling / beamforming can be implemented by positioning the radiation null to a neighboring, unrelated STA. The aforementioned nulling / beamforming can make a particular AP invisible to neighboring, unrelated STAs. For example, the aforementioned nulling / beamforming can make AP1 (or AP2) invisible to STA2 (or STA1).

[0186] For example, in Figure 16 In this BSS, STA1 and AP1 can be included, while STA2 and AP2 can be included in the OBSS. In other words, STA2 can be an STA that is not associated with AP1, and STA1 can be an STA that is not associated with AP2.

[0187] although Figure 16Not illustrated, but control signals (e.g., coordination frames) for nulling / beamforming between AP1 and STA2 and / or for nulling / beamforming between AP2 and STA1 can be transmitted and received on the backhaul link between AP1 and AP2.

[0188] Figure 17 An example of AP selection is illustrated. AP2 is determined to have better channel conditions than AP1. AP1 transmits its data / signals to AP2 via the backhaul link, and AP2 can transmit signals to STA1 in place of AP1. For example, in... Figure 17 In this context, STA1 and AP1 can be included in the BSS, and STA2 and AP2 can be included in the OBSS. In other words, STA2 can be an STA that is not associated with AP1, and STA1 can be an STA that is not associated with AP2.

[0189] Figure 18 An example of JTX / JT is illustrated. AP1 can transmit to STA1 together with AP2. For example, the PPDU / signal transmitted from AP2 to STA1 can be wholly or partially the same as the PPDU / signal transmitted from AP1 to STA1. For example, the PPDU / signal transmitted from AP2 to STA1 can be transmitted simultaneously with the PPDU / signal transmitted from AP1 to STA1 via the same / overlapping frequency band. For example, the PPDU / signal transmitted from AP2 to STA1 can be a signal transmitted from AP1 via the backhaul link. For example, in... Figure 18 In this context, STA1 and AP1 can be included in the BSS, and STA2 and AP2 can be included in the OBSS. That is, STA2 can be an STA that is not associated with AP1, and STA1 can be an STA that is not associated with AP2.

[0190] More specifically, in Figure 18 In this process, AP1 can send a coordination request to AP2 (or it can be named in various ways, such as First Request, Control Request, etc.) and receive a coordination response from AP2 (or it can be named in various ways, such as First Response, Control Response, etc.). Through the exchange of requests / responses, information about the coordination between AP1 and AP2 can be exchanged (e.g., whether AP1 and AP2 will perform simultaneous transmission to STA1), information about the start time of coordination, information about the start time of simultaneous transmission by AP1 and AP2 to STA1, information about the data shared between AP1 and AP2, etc. AP1 can share its data with AP2 via the backhaul link. Afterwards, AP1 can send a coordination trigger frame to AP2 (or it can be named in various ways, such as Trigger Frame), and perform simultaneous transmission to STA1 based on that trigger frame.

[0191] The following describes the link adaptation techniques for OBSS APs / STAs applied in this specification. Specifically, it describes the link adaptation method before determining the multi-AP configuration and the method for performing the probing process after determining the multi-AP configuration.

[0192] <Implementation methods applicable to this specification>

[0193] Figure 19 An example of an OBSS environment is shown.

[0194] An Overlapping Basic Service Set (OBSS) environment refers to a network environment in which a portion of the space with the same channel configuration overlaps between two BSSs. (See reference...) Figure 19 OBSS indicates the overlap or interference between My BSS (MY BSS) that User 1 (STA1) is connected to (via the network of AP1) and the adjacent BSS that User 1 (STA1) is not connected to (via the network of AP2).

[0195] Before determining the above multi-AP configuration, the following link adaptation methods are described: 1) the MLA request / response method for requesting / reporting link information to neighboring APs using the A-control subfield, and 2) the method for configuring the beacon request / response used to obtain link information from neighboring APs to include link information at the RU or sub-channel level.

[0196] First, this specification proposes a link adaptation method for obtaining OBSS channel information for multiple access points in a Wi-Fi system.

[0197] This specification defines link adaptation control fields for obtaining channel information for various multi-AP operations. Specifically, since APs must have information about STAs capable of transmitting data to form a multi-AP network, each STA can be instructed to report the channel state of each AP. While individual probing techniques can be used, the overhead of receiving detailed channel state reports from multiple APs to multiple STAs is significant. Therefore, by including the +HTC (HT control field) when transmitting data to each STA, the STA can be instructed to report a coarse channel state.

[0198] Figure 20 An example of the A-control subfield of the HE variant HT control field is shown.

[0199] Figure 20 The top of the list shows the A-control subfield. (See reference...) Figure 20 At the top, the control list subfields include at least one control subfield. Each control subfield is instantiated as follows: Figure 20 The bottom.

[0200] Reference Figure 20At the bottom, the Control ID subfield indicates the type of information conveyed in the Control Message subfield. The length of the Control Message subfield is fixed for each value not reserved in the Control ID subfield. The length of the Control Message subfield associated with the value of the Control ID subfield is defined as follows.

[0201] [Table 1]

[0202]

[0203] Figure 21 An example of the control information subfield of the ELA control subfield is shown.

[0204] Reference Figure 21 The control information subfield of the ELA control subfield includes information related to the ELA (EHT Link Adaptation) process. The control information subfield includes the non-requested MFB subfield, MRQ / UL EHT TB PPDU MFB subfield, NSS subfield, EHT-MCS subfield, RU allocation subfield, PS160 subfield, BW subfield, MSI / partial PPDU parameter subfield, Tx beamforming subfield, and HLA / ELA subfield.

[0205] If the ELA control is a non-requested MFB, the non-requested MFB subfield is set to 1. If the ELA control is an MRQ or a requested MFB, the non-requested MFB subfield is set to 0.

[0206] To request an ELA response, the MRQ / UL EHT TB PPDU MFB subfield is set to 1, and the non-request MFB subfield is set to 0. To respond to an ELA request, the MRQ / UL EHT TB PPDU MFB subfield is set to 0, and the non-request MFB subfield is set to 0.

[0207] First, a new A-control subfield, namely the control ID, is added for multi-AP link adaptation control. This A-control subfield can be defined by various names such as SNR (signal-to-noise ratio) control, RSSI (received signal strength indicator) control, and is referred to as MLA (multi-AP link adaptation) control in this specification.

[0208] Additionally, the MLA control subfield can be configured with the following information. The content can be configured to be 26 bits or less in length, or multiple MLA control subfields can be configured. When multiple MLA control subfields are configured, the number of MLA control subfields can be fixed, or a flag indicating that it is the last subfield can be added, and this flag can be set to 0 or 1 in the last subfield to indicate that it is the last one.

[0209] 1) When the AP makes a request:

[0210] - For example, the request could be for measuring the RSSI or SNR of a frame that contains the MLA control subfield.

[0211] - For example, the request could be for measuring RSSI or SNR from multiple APs. In this case, the BSS color (6 bits) of the frame to be measured can be specified, and the request can be for measuring RSSI (8 bits) or SNR (8 bits). If the number of BSS colors to be measured is variable, a subfield indicating the number or a flag indicating the last BSS color is required. Alternatively, setting the BSS color to a specific value (e.g., 0) can be used to specify it as the last subfield. Alternatively, the STA can arbitrarily measure and report BSS colors and RSSI / SNR without specifying BSS colors. In this case, the first BSS color can be specified as a specific value (e.g., 0), or the BSS color subfield can be omitted. In this case, the BSS color value can be represented using fewer bits than the number of bits mentioned above. For example, the BSS color can be represented using only 3 to 5 of the total 6 bits, either the most significant bit (MSB) or the least significant bit (LSB).

[0212] 2) When the STA receives a feedback response:

[0213] - For example, RSSI or SNR values ​​can be reported for the indicated frame or for the associated AP.

[0214] - For example, the RSSI or SNR value (8 bits) measured for each indicated BSS color can be reported. If the AP has specified the BSS color, the BSS color subfield can be omitted (this can be assumed since RSSI / SNR values ​​will be sent in the order they are requested). The STA can also provide feedback arbitrarily without a request from the AP.

[0215] - In this case, BSS color or RSSI / SNR values ​​can be represented using fewer bits than those mentioned above. As previously explained for BSS color, RSSI or SNR can be represented with a higher resolution, such as "7 bits, double-interval" or "6 bits, quadruple-interval" instead of 8 bits. Alternatively, the representation range can be reduced by setting values ​​below a certain value to 0 and values ​​above a certain value to the maximum value. For example, if SNR is represented as 8 bits, from -10 dB to 53.75 dB in 0.25 dB increments, the number of bits can be reduced by setting the resolution in 0.5 dB or 1 dB increments, or by limiting the representation range to 0 dB to 31.75 dB.

[0216] The MLA control described in this specification can respond immediately to RSSI or SNR for the indicated frame or associated AP. However, unlike existing HLA control, it may not respond immediately in the response frame of the frame to which the request is entered when additional RSSI or SNR measurements are required. This is because frames from other APs must also be checked and feedback must be provided. Therefore, the response may be independent of the timing of the request or whether a request was made. Alternatively, if the STA reads frames such as beacons in advance and stores RSSI information, it can respond immediately when a request is made to the MLA control. Alternatively, the STA can send a response at a specific time without waiting for a request (a non-request response).

[0217] The following is an example of how to configure the A-control subfield when configuring the MLA control subfield. Here, if the length of the control subfield is set to 26 bits or less, the number of reserved bits can be reduced.

[0218] Figure 22 An example of an A-control subfield used for MLA requests / responses is shown.

[0219] Reference Figure 22 The A-control subfield used for MLA control can be configured by setting the value of the control ID subfield to 9 (or another reserved value). If MRQ is 0, the A-control subfield is used for MLA requests, and the remaining 25 bits can be reserved. If MRQ is 1, the A-control subfield is used for MLA responses, which can include an RSSI value, and the remaining 17 bits can be reserved.

[0220] Figure 23 Another example of an A-control subfield used for MLA requests / responses is shown.

[0221] Reference Figure 23 The A-Control subfield used for MLA control can be configured by setting the value of the Control ID subfield to 9 (or another reserved value). When MRQ is 0, the A-Control subfield is used for MLA requests and can include a BSS Color subfield to indicate the measurement of RSSI (or SNR) for multiple APs. For example, the A-Control subfield can include BSS Color 1, BSS Color 2, and BSS Color 3 subfields to indicate the measurement of RSSI (or SNR) for each AP.

[0222] When MRQ is 1, the A-control subfield is used for the MLA response and responds by including the RSSI values ​​(RSSI1, RSSI2, RSSI3) based on the BSS color, and the remaining 1 bit can be reserved.

[0223] Figure 24 Another example of an A-control subfield used for MLA requests / responses is shown.

[0224] Reference Figure 24 The A-control subfield used for MLA control can be configured by setting the value of the control ID subfield to 9 (or another reserved value). When MRQ is 0, the A-control subfield is used for MLA requests, and the remaining 25 bits can be reserved.

[0225] When MRQ is 1, the A-control subfield is used for MLA responses, and Figure 24 An example consisting of two MLA control subfields is shown.

[0226] The two MLA control subfields used for the above MLA response include a BSS color subfield and an RSSI (or SNR) value for that BSS color subfield. For example, the first MLA control subfield can respond with BSS color 1, RSSI 1 based on BSS color 1, BSS color 2, and RSSI 2 based on BSS color 2, and an end flag can be inserted and set to 0 to indicate that it is not the last MLA control subfield (continue). The second MLA control subfield can respond with BSS color 3, RSSI 3 based on BSS color 3, BSS color 4, and RSSI 4 based on BSS color 4, and an end flag can be inserted and set to 1 to indicate that it is the last MLA control subfield (end).

[0227] As another example, a link adaptation method utilizing group IDs defined for multi-AP operations is proposed.

[0228] A group ID for multi-AP operations is an identifier that collectively represents the set of APs participating in the multi-AP operation. It can be defined differently depending on the type of multi-AP operation (e.g., ID for C-OFDMA, ID for C-SR, etc.). Alternatively, a single BSS AP can be included in multiple multi-AP operation sets and therefore belong to multiple IDs. This definition can be newly defined or can reuse existing standard group IDs, such as Mobile Domain Identifiers (MDIDs). This is referred to herein as the Multi-AP ID (MA ID), and detailed configuration methods are not covered in this specification. An example of the structure of an MLA request and response using this ID is shown below.

[0229] When the BSS AP issues an MLA request, it indicates the MAID to be measured. The measurement start time, measurement duration, or channel information to be measured (e.g., RU allocation) can be set based on the MAID. (Alternatively, setting the MAID as the default eliminates the need for separate signaling.)

[0230] The STA receiving an MLA request or making an MLA response can include the MAID of the measurement. It can respond in the order of the BSSs included in the MAID. Alternatively, it can include an index of that order to replace the previous BSS colors. Alternatively, it can provide a bitmap of the APs included in the measurement during that order. (This reduces the number of bits used compared to listing the BSS colors previously.) For example, the AP index can be used to determine which AP's RSSI is being measured.

[0231] Feedback values ​​can be various channel values ​​(including those mentioned above), such as Receive Channel Power Indicator (RCPI), Receive Power Indicator (RPI), Average Noise Power Indicator (ANPI), and Receive Signal-to-Noise Ratio Indicator (RSNI). It can be a value for the entire frequency band, a value for the entire frequency band excluding disabled sub-channels, or a value for the frequency band including RU allocations. It can also include information about disabled sub-channels, preferred / avoided / idle sub-channels, etc. (For example, RU allocation can indicate preferred / avoided / idle sub-channels.) One or more of these feedback values ​​can be included and transmitted.

[0232] In an MLA response, one A-control can be used for each OBSS AP's channel value. When reporting channel values ​​for two OBSS APs, such as... Figure 25 As shown, two A-control subfields can be used.

[0233] Figure 25 Another example of an A-control subfield used for MLA requests / responses is shown.

[0234] Reference Figure 25 When MRQ is 1, the A-control subfield is used for MLA responses, and Figure 25 An example is shown that includes two MLA control subfields for two OBSS APs.

[0235] The two MLA control subfields used for the above MLA response can respond with the RU allocation and RSSI (including the MAID and AP indexes) for each OBSS AP. For example, the first MLA control subfield for the first OBSS AP can respond with the RU allocation and RSSI value based on the MAID and AP indexes, and an end flag can be inserted and set to 0 to indicate that it is not the last MLA control subfield (continue). The second MLA control subfield for the second OBSS AP can respond with the RU allocation and RSSI value based on the MAID and AP indexes, and an end flag can be inserted and set to 1 to indicate that it is the last MLA control subfield (end).

[0236] While all the above implementations suggest information or configurations that can be included in the MLA subfields of A-control, new control frames can also be defined. For example, they can be sent together with other frames as Aggregate-MAC Protocol Data Units (A-MPDUs).

[0237] In other words, this embodiment proposes a method for obtaining channel information for multiple AP operations by defining an A-control subfield for MLA control. To this end, the AP requests channel information from the STA using the A-control subfield for MLA control, and the STA responds to this request using the A-control subfield for MLA control.

[0238] In addition, this specification presents a radio measurement procedure for OBSS channel measurement in Wi-Fi systems.

[0239] An AP participating in space reuse can request beacon reports from its associated non-AP STA to obtain channel information about its neighbors (OBSS APs). This information may include the operation category, channel number, frame type and PHY type of the measurement frame, RCPI, RSNI, BSSID, etc. Optionally, the requested information may also include the frame body information of the measurement frame, or, in 802.11be, information on disabled sub-channels.

[0240] This specification proposes methods for obtaining more refined neighbor channel information to improve spatial reuse or efficiently operate multi-AP technologies.

[0241] Spatial reuse (SR), introduced in 802.11ax WLAN systems, improves spectral efficiency by increasing the number of parallel transmissions. SR allows adjustment of the carrier sense threshold (CST) for detected inter-BSS transmissions. CST adjustment is achieved through two mechanisms: i) SR based on overlapping Basic Service Set Packet Detection (OBSS PD), and ii) parameterized spatial reuse (PSR).

[0242] The key difference between these two mechanisms lies in the degree of coordination between BSSs to identify SR-based opportunities. Both mechanisms include transmit power control (TPC), which limits additional interference generated by concurrent transmissions.

[0243] SR operation was introduced as a mechanism to increase the number of transmits stored in the OBSS and improve spectral efficiency. In some cases, dynamic sensitivity and transmit power adjustment have been shown to significantly improve network performance and alleviate the well-known hidden / exposed device problem. However, in other cases, modifying CST or transmit power may exacerbate the hidden / exposed device problem by causing flow starvation and asymmetry.

[0244] Figure 26This diagram illustrates the effects of increasing and decreasing transmit power and sensitivity in a WLAN. For example, increasing sensitivity may facilitate more frequent channel access because it reduces the carrier sense (CS) area. However, this may lead to a greater number of collisions observed due to hidden nodes. Furthermore, using a more aggressive channel access strategy may expose the receiver to higher levels of interference, thus requiring a more robust modulation and coding scheme (MCS).

[0245] SR operation relies on Dynamic Idle Channel Assessment / Carrier Sense / CS (CCA / CS) adjustments to increase the number of Transmission Opportunities (TXOPs) in the OBSS. A Wi-Fi device triggers the CCA / CS mechanism when it detects a preamble transmitted by another device. If the received signal quality is poor, detected transmissions (exceeding the physical sensitivity threshold) may not be decoded correctly. Conversely, for decoded transmissions exceeding the CCA / CS threshold, physical or virtual carrier sense operation sets the medium to busy. Furthermore, the capture effect is used when multiple signals are detected, allowing the device to lock onto the strongest signal without experiencing packet collisions.

[0246] Figure 27 This is an example of a CS area in a WLAN system.

[0247] The above concepts are illustrated in Figure 27 In. Figure 27 In the middle, the center's AP A It can detect received signals exceeding the sensitivity of the antenna receiver, but can only decode signals above the CCA / CS threshold. Furthermore, 11ax SR operation uses the OBSS / PD threshold to allow ignoring AP signals. B This improves channel utilization. Furthermore, transmit power limiting applies to TXOPs detected using OBSS / PD thresholds. Figure 13 In this system, the transmission power is fixed, and all devices use the same frequency channel.

[0248] 1) SR based on OBSS PD

[0249] Upon receiving a PPDU, the MAC layer of the specific device receives a notification from the PHY. The node then examines the frame and, in other actions, determines whether the PPDU is an intra-BSS frame or an inter-BSS frame. By quickly identifying the source of an ongoing transmission, the HE STA can use an appropriate OBSS / PD value to improve its chances of accessing the channel.

[0250] 802.11ax defines a set of rules to limit the OBSS / PD threshold, which has the following upper limits:

[0251] OBSS / PD <= max(OBSS / PD) minmin(OBSS / PD) max OBSS / PD min +(TX_PWR ref -TX_PWR)))

[0252] Here, OBSS / PD min and OBSS / PD max -82dBm and -62dBm respectively, reference power TX PWR ref The capability of the device is 21dBm or 25dBm, and TX PWR refers to the transmit power (in dBm) of the HE node at the antenna connector for identifying SR-based TXOP.

[0253] Figure 28 This is a graph illustrating OBSS / PD and transmit power adjustment rules.

[0254] SR operation (along with sensitivity adjustment) includes a transmit power limit for all transmissions resulting from detected SR TXOP (i.e., after ignoring the inter-BSS frames given by OBSS / PD-based SR operation). Maximum allowed transmit power (TXPWR) max The definition is as follows:

[0255] TX PWR max =TX PWR ref -(OBSS / PD-OBSS / PD min )

[0256] The above formula in OBSS / PD max >=OBSS / PD>OBSS / PD min The condition is met when the maximum transmit power is not limited. Otherwise, the maximum transmit power is unrestricted. By applying power limits, the OBSS / PD value is designed to reduce the impact of simultaneous transmissions caused by SR.

[0257] Simply put, the higher the OBSS / PD threshold (which allows for more inter-BSS transmissions to be ignored), the lower the transmission power (which should generate less interference). The transmission power limit continues until the end of the SR TXOP identified by the HE node, which begins when backoff reaches 0. This duration depends on the active transmission period used to detect the SR TXOP.

[0258] 2) PSR (Parameterized Space Reuse)

[0259] PSR operation is defined as an alternative to OBSS / PD-based SR for TB transmission.

[0260] Nodes utilizing PSR opportunities identify them from detected TB transmissions. On the other hand, opportunists perform TB transmissions and look for a sender holder indicating support for PSR operation in the trigger frame (TF) header. To identify PSR opportunities, opportunists must determine whether a TB PPDU following a given TF packet can be ignored.

[0261] Therefore, the opportunist's expected transmission power must not exceed the requirement imposed by the transmission holder (encapsulated in the PSR_INPUT parameter).

[0262] The opportunist checks the PSR value of the detected TF and, if the expected transmit power is acceptable (indicated in the Common Information field), transmits during the TB PPDU. Specifically, the expected transmit power must be less than the PSR value measured in the conventional part of the TF (i.e., the PHY header) minus the Receive Power Level (RPL). The PSR value is calculated as follows:

[0263] PSR = TX PWR AP +I AP max

[0264] Here, TX PWRAP is the normalized transmit power (in dBm) at the output of the antenna connector, and I... AP max It is a normalized value (in dB) of the maximum allowable interference in the captured transmitter. Specifically, I AP max The target RSSI indicated in the TF is calculated as the minimum SNR allowed by 10% PER (based on the highest MCS for UL HE TB PPDU transmission). A 5dB safety margin (set at the AP) is also included to ensure that it does not exceed that value.

[0265] In an 802.11ax wireless LAN system, a HE AP participating in spatial reuse can send a beacon request to request an associated non-AP HE STA to collect information about its neighbors. The non-AP HE STA performing spatial reuse responds to the beacon request with a beacon report.

[0266] Figure 29 An example of the measurement request field format for a beacon request is shown.

[0267] Figure 29 The measurement request fields include the operation category field, channel number field, randomization interval field, measurement duration field, measurement mode field, BSSID field, and optional sub-element field.

[0268] The optional child element ID for the beacon request is set as follows:

[0269] [Table 2]

[0270] Child element ID name Scalability 0 SSID no 1 Beacon Report yes 2 Report details yes 3-9 reserve 10 ask no 11 Extended Request no 12-50 reserve 51 AP Channel Report no 52-162 reserve 163 Wideband channel switching yes 164 Final beacon report instruction request no 165-220 reserve 221 Manufacturer-specific Manufacturer definition 222-255 reserve

[0271] Figure 30 An example of the measurement report field format for a beacon report is shown.

[0272] Figure 30 The measurement report fields include the operation category field, channel number field, actual measurement start field, measurement duration field, reported frame information field, RCPI field, RSNI field, BSSID field, antenna ID field, parent TSF field, and optional child element field.

[0273] The optional sub-element ID settings for the beacon report are as follows.

[0274] [Table 3]

[0275] Child element ID name Scalability 0 reserve 1 Report frame body no 2 Report frame body segment ID no 3-162 reserve 163 Wideband channel switching yes 164 Final beacon report instructions no 165-220 reserve 221 Manufacturer-specific Manufacturer definition 222-225 reserve

[0276] Essentially, neighbor channel information is reported by the BSS STA to the BSS AP by incidentally hearing management frames (such as beacons) from the OBSS AP. This specification describes methods for requesting and reporting channel information for the entire BW band as well as for specific BW, RU, or sub-channels.

[0277] As an example of how this can be applied, existing beacon reports ( Figure 31 The measurement report field can provide RCPI (Received Channel Power of Beacon, Measurement Pilot, or Probe Response Frame) or RSNI (Received Signal-to-Noise Ratio Indication) information for the entire frequency band, as well as RCPI or RSNI for RU or sub-channel units. For example, reserved values ​​of optional sub-elements can be used to indicate or report the following information.

[0278] For example, if sub-element ID = 166, the beacon report reports channel information in units of RU or sub-channel (20MHz), or reports channel information for a frequency range specified in the RU allocation. The reported channel information can be not only about existing RCPI or RSNI, but also SINR, Received Signal Strength Indicator (RSSI), Received Power Indicator (RPI), Average Noise Power Indicator (ANPI), Idle Power Indicator (IPI), Received Channel Power Indicator (RCPI), Received Signal-to-Noise Ratio Indicator (RSNI), etc. One or more of the above information can be included in the beacon report.

[0279] When this sub-element ID is included in the beacon request, the STA must report channel information in units of RU or sub-channel (20MHz). The RU or sub-channel unit can be fixed to a default value (e.g., 20MHz or 242-tone RU) or indicated by an indicator. Alternatively, an RU allocation sub-field can be included in the beacon report to indicate the channel to be reported.

[0280] The beacon report may include the sub-element ID and channel information for each RU or sub-channel, or channel information for a frequency range specified in the RU allocation. The length of the report frame may vary depending on the amount of channel information to be reported. Furthermore, if disabled sub-channel information is included, the information for the sub-channel can be omitted from the beacon report, or the sub-channel can be reported as unavailable (RCPI value = 255).

[0281] The channel information of the OBSS AP can facilitate more refined SR (spatial reuse) operations or multi-AP operations. For example, when C-OFDMA is applied between APs in 20MHz units, C-SR can be applied within that 20MHz space. Alternatively, with the introduction of 20MHz punched channels, methods such as transmitting data in SR only in the 20MHz units where SR is possible can be applied.

[0282] Although referred to here as OBSS AP, in the context of multi-link operation, it can also be applied to links in an MLD (Multi-Link Device) where a specific AP or STA does not transmit or receive data, or links where data is not associated. For example, if AP1 through AP3 are included in the AP MLD, and STA1 through STA3 are included in the STA MLD, then AP1 sends a beacon request to STA1 in the STA MLD via link 1, and STA1 sends a beacon report to AP1, thus AP1 can obtain channel information about AP2 and AP3 for another link.

[0283] The multi-AP configuration can be set based on the channel information (MLA control information (RSSI or SNR), measurement report information per RU or sub-channel (RCPI, RSNI, etc.)) obtained through the above implementation method.

[0284] The following describes a method for performing a probe procedure after a multi-AP configuration has been established. 1) A method for setting an OAID for a non-associated STA to obtain channel information about surrounding APs is described.

[0285] This specification presents a method for setting up an AID in a Wi-Fi system and performing an NDP probe procedure between the OBSS AP and the BSS STA.

[0286] In the current standard, the NDP probe procedure defines the process by which a BSS AP requests and receives feedback from a STA within the BSS. If multi-AP technology is introduced, the STAs within the BSS may require channel information from both the BSS AP and the OBSS AP. Therefore, this specification proposes a method for an OBSS AP to perform NDP probes to a BSS STA. From the BSS AP's perspective, this can also be applied to a method for a BSS AP to perform NDP probes to an OBSS STA. In other words, the procedure described below can be applied to both the NDP probe process between an OBSS AP and a BSS STA, and the NDP probe process between a BSS AP and an OBSS STA.

[0287] Although this manual mentions BSS AP and OBSS AP, this can also be applied to every link in MLD.

[0288] Figure 31 An example of the trigger frame format is shown.

[0289] A trigger frame requests the transmission of at least one TB PPDU and the allocation of resources for it. The trigger frame may include additional information requested by the responding STA for the transmission of the TB PPDU.

[0290] Figure 31 The trigger frame includes the frame control field, duration field, RA field, TA field, public information field, user information list field, fill field, and FCS field.

[0291] Figure 32 An example of the NDP announcement frame format is shown.

[0292] There are three variants of the NDP announcement frame: VHT NDP announcement frame, HE NDP announcement frame, and EHT NDP announcement frame. Each variant is distinguished by the configuration of the HE subfield and the ranging subfield within the probe dialogue token field.

[0293] VHT / HE / EHT NDP advertisement frames contain at least one STA information field. If a VHT / HE / EHT NDP advertisement frame contains only one STA information field, the RA field is set to the address of the STA capable of providing feedback. If a VHT / HE / EHT NDP advertisement frame contains more than one STA information field, the RA field is set to the broadcast address.

[0294] The TA field is set to the address of the STA that sends the VHT / HE / EHT NDP advertisement frame, or the bandwidth signaling TA of the STA that sends the VHT / HE / EHT NDP advertisement frame.

[0295] The resolution subfield in the partial BW information subfield indicates the resolution bandwidth for each bit of the feedback bitmap subfield. The feedback bitmap subfield indicates the request for each resolution bandwidth from the lowest to the highest frequency, where B1 indicates the lowest resolution bandwidth. If feedback is requested for a corresponding resolution bandwidth, each bit of the feedback bitmap subfield is set to 1.

[0296] The resolution bit indicates the feedback resolution bandwidth. When the BW subfield is set to 0 through 3, the resolution bit is set to 0 to indicate a resolution of 20 MHz; and when the BW subfield is set to 4, the resolution bit is set to 1 to indicate a resolution of 40 MHz. The feedback bitmap subfield indicates the beamforming transmission policy for each resolution bandwidth it requests feedback on. If feedback is requested for the corresponding bandwidth, each bit in the feedback bitmap subfield is set to 1; otherwise, it is set to 0.

[0297] When the bandwidth of the EHT NDP announcement frame is less than 320MHz, the resolution bit B0 is set to 0 to indicate a resolution of 20MHz.

[0298] - When the bandwidth of the EHT NDP announcement frame is 20MHz, B1 is set to 1 to indicate a feedback request to the 242 tone RU. B2-B8 are reserved and set to 0.

[0299] - When the bandwidth of the EHT NDP announcement frame is 40MHz, B1 and B2 indicate feedback requests for the two 242-tone RUs from low to high frequencies. B3-B8 are reserved and set to 0.

[0300] - When the bandwidth of the EHT NDP announcement frame is 80MHz, B1-B4 indicate feedback requests for each of the four 242-tone RUs from low to high frequencies. B5-B8 are reserved and set to 0. If all B1-B4 are set to 1, this indicates a feedback request for 996-tone RUs.

[0301] - When the bandwidth of the EHT NDP announcement frame is 160MHz, B1-B8 indicate feedback requests for each of the eight 242-tone RUs from low to high frequencies. If all of B1-B4 are set to 1, this indicates a feedback request for the lower 996-tone RU; and if all of B5-B8 are set to 1, this indicates a feedback request for the higher 996-tone RU.

[0302] When the bandwidth of the EHT NDP announcement frame is 320MHz, the resolution bit B0 is set to 1 to indicate a resolution of 40MHz. B1 through B8 represent feedback requests for each of the eight 484-tone RUs from low to high frequencies. When both B1 and B2 are set to 1, it indicates a feedback request for the lowest 996-tone RU; when both B3 and B4 are set to 1, it indicates a feedback request for the second lowest 996-tone RU; when both B5 and B6 are set to 1, it indicates a feedback request for the second highest 996-tone RU; and when both B7 and B8 are set to 1, it indicates a feedback request for the highest 996-tone RU.

[0303] The detection protocol can be described as follows. Since the standardization phase is not yet complete, the detection protocol described below is written for EHT wireless LAN systems, but it can also be applied to UHR wireless LAN systems or next-generation wireless LAN systems.

[0304] Transmit beamforming and downlink multiple-user multiple-input multiple-output (DLMU-MIMO) require knowledge of channel conditions to compute steering matrices applied to the transmitted signal, thereby optimizing reception at one or more receivers. EHT STA uses the EHT probe protocol to determine channel condition information. The EHT probe protocol provides explicit feedback mechanisms, defined as EHT non-trigger-based (non-TB) probe and EHT trigger-based (TB) probe. Here, the EHT beamforming receiver measures the channel using a training signal transmitted by the EHT beamforming transmitter (i.e., EHT probe NDP) and transmits back a transformed estimate of the channel conditions. The EHT beamforming transmitter uses this estimate to derive the steering matrix.

[0305] The EHT beamforming transmitter returns an estimate of the channel state from EHT compressed beamforming / CQI reports contained in one or more EHT compressed beamforming / CQI frames. There are three types of EHT compressed beamforming / CQI reports.

[0306] -SU Feedback: The EHT Compressed Beamforming / CQI report consists of EHT Compressed Beamforming report fields.

[0307] -MU Feedback: The EHT Compressed Beamforming / CQI report consists of the EHT Compressed Beamforming Report field and the EHT MU-specific Beamforming Report field.

[0308] -CQI Feedback: The EHT Compressed Beamforming / CQI report consists of EHT CQI report fields.

[0309] Note that the use of EHT TB probing does not necessarily imply MU feedback. EHT TB probing is also used to obtain SU feedback and CQI feedback.

[0310] Figure 33 An example of EHT non-TB detection is shown.

[0311] The EHT non-TB probe sequence is initiated by the EHT beamforming transmitter using a separately addressed EHT NDP announcement frame, which contains exactly one STA information field. Following the SIFS, an EHT probe NDP is performed. The EHT beamforming transmitter responds with an EHT compressed beamforming / CQI frame after the SIFS.

[0312] The AID11 subfield of the STA information field must be set to the AID of the STA identified by the RA field of the EHT NDP advertisement frame; if the STA identified by the RA field is a mesh STA, AP, or IBSS STA, then set it to 0.

[0313] Figure 33 An example of an EHT non-TB probe sequence with a single EHT beamforming transmitter is shown.

[0314] Figure 34 An example of EHT TB detection is shown.

[0315] The EHT TB probe sequence is initiated by the EHT beamforming transmitter using a broadcast EHT NDP advertisement frame with two or more STA information fields. An EHT probe NDP is sent after the SIFS, followed by a Beamforming Report Polling (BFRP) trigger frame. Each EHT beamforming receiver responds after the SIFS with an EHT TB PPDU containing one or more EHT Compact Beamforming / CQI frames. The BFRP trigger frame sent within the EHT TB probe sequence must request an EHT TB PPDU.

[0316] Figure 13 An example of an EHT TB probe sequence with two or more EHT beamforming receivers is shown.

[0317] The EHT beamforming transmitter that initiates the EHT TB probe sequence must send an EHT NDP announcement frame, which contains two or more STA information fields and an RA field set as the broadcast address.

[0318] An EHT beamforming transmitter can initiate an EHT TB probe sequence to request SU, MU, or CQI feedback.

[0319] Currently, the 802.11ax and 802.11be standards do not define how the OBSS AP applies the NDP probe procedure to the BSSSTA. However, in the future, the use of OBSS channel information with NDP probes may be necessary for reasons such as using multi-AP technology or more effectively applying spatial reuse. This can also be applied to NDP probes on other links for multi-link operation. Therefore, although we will refer to the OBSS AP in the future, this can be replaced by links on which the STA does not transmit or receive or is not associated. Furthermore, the channel value measurement performed by the BSS STA in response to the NDP probe transmission of the OBSS AP is described below, but this can naturally be interpreted and applied to the channel value measurement performed by the OBSS STA in response to the NDP probe transmission of the BSS AP. Figure 35 Examples are given of channel value measurements performed by the BSS STA in response to NDP probe transmissions from the OBSS AP, and channel value measurements performed by the OBSS STA in response to NDP probe transmissions from the BSS AP.

[0320] This specification proposes using the so-called OAID (OBSS STA AID) instead of using AID to allow the AP to identify (or even send / receive) STAs in unrelated neighbors. That is, just as the STAID between a BSS AP and a BSS STA is defined as an AID, the STA ID between an OBSS AP and a BSS STA (or the STA ID between a BSS AP and an OBSS STA) is pre-defined as OAID. (The terminology used to refer to this can be anything other than OAID (OBSS AID), but it is referred to as OAID in this specification.)

[0321] In 802.11az, an ID called RSID is assigned to unassociated BSS STAs, and FTM negotiation is performed via RSID. According to the 802.11az standard, after pre-associated security negotiation, an FTM request frame is sent to the ISTA (Initiating STA), and an IFTM frame (Initial FTM frame) is received from the RSTA (Responding STA) to complete the FTM negotiation. Here, the AID / RSID field is included in the TB-specific sub-element of the ranging parameter element included in the IFTM frame. If the ISTA is not associated with an RSTA, the AID / RSID field is set to the RSID assigned by the responder to identify the unassociated ISTA with the same length as the AID.

[0322] This specification uses this method to define and utilize OAID. Specifically, OAID is used in the NDP probing process for OBSS channel acquisition to enable the OBSS AP to perform NDP probing (or even other transmit and receive) with the BSS STA. (Detailed establishment, configuration, and allocation of OAID are not covered in this specification.)

[0323] The OBSS NDP probe process for obtaining OBSS channel information is described in this specification as follows. Figures 35 to 37 An example of applying the OBSS NDP probing procedure is shown.

[0324] Figure 35 An example of the NDP probe procedure for obtaining OBSS channel information is shown.

[0325] Figure 35 The NDP detection process mainly includes steps 1) to 5).

[0326] 1) OAID negotiation: OBSS AP assigns OAID to identify BSS STA.

[0327] - Although the allocation method and process are not detailed in this specification, as an example, the BSS AP can assign an OAID to a BSS STA that requires OBSS channel measurements. The BSS STA requiring OBSS channel measurements can be a STA with multi-AP capability (or more specifically, capability specific to each multi-AP technology) or a STA with OBSS channel measurement capability. Alternatively, the BSS STA requiring OBSS channel measurements can be a STA belonging to a group operating multiple APs (specifically, specific to a particular technology). In this case, the OAID can be assigned as requested or unrequested by defining a new management frame for OBSS channel measurements, or by adding a subfield or element (also known as an OAID assignment frame / (sub)element) to an existing management frame. This OAID information must be shared with the OBSS AP.

[0328] -OAID negotiation is a pre-process that must be performed before the OBSS NDP probing process begins.

[0329] 2) Triggering of the OBSS Probe Process: The BSS AP instructs the OBSS AP and BSS STA to initiate the OBSS probe process. This instruction frame (trigger frame, see...) Figure 31 The content can be as follows.

[0330] The TA address is the BSSID of the BSS. The RA address can be set to broadcast and can include a separate indicator known as an indicator frame for OBSS probes. Alternatively, the RA address can be set to a BSSID specifically designated for OBSS probes.

[0331] - The trigger frame must include the ID information of the OBSS AP (e.g., BSSID, BSS color, BSS index of multiple AP groups, etc.). This allows the OBSS AP with its ID information to be ready to send NDPA and NDP.

[0332] - BSS STAs that require OBSS channel measurements can use the above information to prepare to receive OBSS probes and provide feedback. Alternatively, AID / OAID can be included in the trigger frame to specify the BSS STAs that will participate in the OBSS NDP probe process.

[0333] - This instruction frame (trigger frame) can be used to configure the TXOP (Transmission Opportunity) for the entire OBSS probe process. For example, the MU-RTS trigger frame can be used to configure the SP (Service Hour) interval for r-TWT (Constrained Target Wake-up Time).

[0334] - An example of configuring this instruction frame would be to define a new trigger type, setting RA=Broadcast and TA=BSSID. Subfields within the public information field, such as other LTFs, would be set to reserved. Trigger-related public information can also be defined to include the OBSSID and the AID / OAID of the BSS STA participating in this OBSS NDP probe. In this case, the newly defined trigger frame may not include user-specific fields.

[0335] - The transmission of this instruction frame can be omitted, and process 3 can begin immediately.

[0336] 3) NDPA and NDP for OBSS probes: The OBSS AP sends an NDPA (NDP Advertisement) frame (see...). Figure 32 ) and NDP detection.

[0337] - At this point, the TA address of the NDPA can be set to the BSSID of the OBSS AP. The RA address of the NDPA can be set to broadcast or to a BSSID specifically designated for OBSS probes. In this case, a separate NDPA (and NDP) indicator for OBSS probes can be included in the NDPA.

[0338] - At this point, the AID11 subfield in the STA information field of the NDPA can be set to the AID / OAID included in the indicator in step 2). The U-SIG of the NDP (the UHR-SIG or next SIG containing public information) can also use a verification bit to indicate that it is an NDP used for OBSS probing.

[0339] - At this point, NDPA can be sent by the BSS AP, and only NDP can be sent by the OBSS AP. However, in this case, since the OBSS AP must send NDP after the SIFS following the NDPA, it must preemptively stop and prepare all transmissions and receptions, including those within the OBSS. In this situation, the BSS AP can send NDPA only to the BSS STA.

[0340] 4) Triggering for OBSS probes: If there are NDPA and NDP for multiple BSS STAs, the OBSS AP can send a trigger frame to configure the resources to be fed back. Alternatively, since this is a resource allocation for a BSS STA, the trigger frame can be sent by the BSS AP.

[0341] 5) Feedback: The BSS STA can feed back information about the OBSS channel obtained from the NDP probe to the OBSS AP or BSS AP.

[0342] Here, the interval between each frame in steps 2) to 5) can be xIFS (or SIFS).

[0343] Between steps 3) and 4), the BSS AP can send an acknowledgment message to the OBSS AP indicating that NDPA and NDP have been sent correctly.

[0344] If steps 2) through 5 (excluding step 1) are defined as the NDP probing process for an OBSS AP (step 1 is a pre-configuration step of the NDP probing process for an OBSS AP and only needs to be performed before the NDP probing process), then this NDP probing process can be repeated more than once. For example, NDP probing for multiple OBSS APs can be performed sequentially and repeatedly. Alternatively, the trigger of step 2) can be used to indicate NDP probing to multiple OBSS APs at once, and only steps 3) through 5) can be repeated. However, since frames may not be heard between the OBSS AP and the BSS STA, it may be preferable to repeat from the trigger of step 2). In other words, after the NDP probing process for one OBSS AP is completed, the BSS AP can send an indication frame for the trigger again. In this case, the first trigger frame (the first trigger frame) may only include information about the OBSS AP and the BSS STA that will then immediately perform the probing process (see [link to relevant documentation]). Figure 36 (Example in [reference]). Alternatively, the first trigger frame (the first trigger frame) may include information about both the OBSS AP and the BSS STA, which will subsequently perform the probing process immediately (see [reference]). Figure 37(Example in the example). In this case, the TXOP length, service period, or duration can be set to include only sections containing information about the OBSS AP and BSS STA that will subsequently perform a probe process immediately (see example in the example). Figure 36 (Example in the text), or it can be set to include a section that includes information about both the OBSS AP and BSS STA, which are then immediately executed during the probing process (see example in the text). Figure 37 (Example in the text).

[0345] Figure 36 An example of the NDP probing process for OBSS AP is shown.

[0346] Reference Figure 36 The BSS AP can sequentially instruct two OBSS APs (AP1 and AP2) to perform the NDP probing process.

[0347] First, the BSS AP can send a first trigger frame to AP1 to establish the TXOP period of the first trigger frame. During the TXOP period of the first trigger frame, an NDP probe procedure can be performed between AP1 and the BSS STA.

[0348] Additionally, the BSS AP can send a second trigger frame to AP2 to set the TXOP period of the second trigger frame. During the TXOP period of the second trigger frame, an NDP probe procedure can be performed between AP2 and the BSS STA.

[0349] Figure 37 Another example of the NDP probing process for OBSS AP is shown.

[0350] Reference Figure 37 The BSS AP can sequentially instruct two OBSS APs (AP1 and AP2) to perform the NDP probing process.

[0351] First, the BSS AP can send a first trigger frame to AP1 and AP2 to establish the TXOP period of the first trigger frame. During the TXOP period of the first trigger frame, an NDP probe procedure can be performed between AP1 and the BSS STA.

[0352] Additionally, the BSS AP can send a second trigger frame to AP2 to set the TXOP period of the second trigger frame. During the TXOP period of the second trigger frame, an NDP probe procedure can be performed between AP2 and the BSS STA.

[0353] At this time, the TXOP period of the first trigger frame may include the TXOP period of the second trigger frame. Figure 37 Examples and Figure 36The difference between the examples lies in whether the TXOP period of the first trigger frame is set longer or shorter. A longer TXOP period allows the OBSS NDP probe process to be performed at various points in time.

[0354] Figure 38 This is a flowchart illustrating the operation of the transmitting device according to this embodiment.

[0355] Figure 38 Examples can be performed by the transmitting device (AP and / or non-AP STA).

[0356] Figure 38 Some steps in the example (or detailed sub-steps described later) can be skipped / omitted.

[0357] Through step S3810, the transmitting device (transmitting STA) can obtain information about the aforementioned tone plan. As described above, the information about the tone plan includes the size and location of the RU, control information related to the RU, information about the frequency band including the RU, and information about the STA receiving the RU, etc.

[0358] In step S3820, the transmitting device can construct / generate a PPDU based on the acquired control information. Configuring / generating a PPDU may include configuring / generating each field of the PPDU. Specifically, step S3820 includes configuring the EHT-SIG field, which includes control information regarding the tone plan. That is, step S3820 includes configuring fields that include control information (e.g., an N-bitmap) indicating the size / location of the RU; and / or configuring fields that include the identifier (e.g., AID) of the STA receiving the RU.

[0359] Furthermore, step S3820 may include generating an STF / LTF sequence transmitted via a specific RU. The STF / LTF sequence may be generated based on a preset STF generation sequence / LTF generation sequence.

[0360] In addition, step S3820 may include generating a data field (i.e., MPDU) sent through a specific RU.

[0361] The transmitting device can send the PPDU constructed in step S3820 to the receiving device based on step S3830.

[0362] While performing step S3830, the transmitting device may perform at least one of operations such as CSD, spatial mapping, IDFT / IFFT operation, and GI insertion.

[0363] The signals / fields / sequences constructed according to this specification can be used as follows: Figure 5 Send in the form of.

[0364] Figure 39 This is a flowchart illustrating the operation of the receiving device / apparatus according to this embodiment.

[0365] According to Figure 39 The example is used to receive the above PPDU.

[0366] Figure 39 Examples can be performed by the receiving device / app (AP and / or non-AP STA).

[0367] Figure 39 Some steps in the example (or detailed sub-steps described later) can be skipped / omitted.

[0368] The receiving device (receiving STA) can receive all or part of the PPDU through step S3910. The received signal can be... Figure 5 In the form of.

[0369] The sub-steps of step S3910 can be based on Figure 38 Step S3830 is used to determine this. That is, in step S3910, the results of the CSD, spatial mapping, IDFT / IFFT operations, and GI insertion operations applied in step S3830 can be recovered.

[0370] In step S3920, the receiving device may perform decoding on all or part of the PPDU. Furthermore, the receiving device can obtain control information related to the tone plan (i.e., RU) from the decoded PPDU.

[0371] More specifically, the receiving device can decode the L-SIG and EHT-SIG of the PPDU based on conventional STF / LTF and obtain the information included in the L-SIG and EHT-SIG fields. The information about various tone schemes (i.e., RUs) described in this specification can be included in the EHT-SIG, and the receiving STA can obtain information about tone schemes (i.e., RUs) through the EHT-SIG.

[0372] In step S3930, the receiving device can decode the remaining portion of the PPDU based on the information about the tone scheme (i.e., RU) obtained in step S3920. For example, the receiving STA can decode the STF / LTF field of the PPDU based on the information about a scheme (i.e., RU). Furthermore, the receiving STA can decode the data field of the PPDU based on the information about the tone scheme (i.e., RU) to obtain the MPDU included in the data field.

[0373] Furthermore, the receiving device can perform a processing operation to transmit the data decoded in step S3930 to a higher layer (e.g., the MAC layer). Additionally, when the upper layer instructs the PHY layer to generate a signal in response to data sent to the upper layer, subsequent operations can be performed.

[0374] In the following text, reference will be made to Figures 1 to 39 The above implementation method is described.

[0375] Figure 40 This is a flowchart illustrating the process of performing OBSS detection for OBSS AP and BSS STA according to this embodiment.

[0376] Figure 40 The example can be implemented in network environments that support next-generation wireless LAN systems (Ultra-High Reliability (UHR) wireless LAN systems or next-generation Wi-Fi). Next-generation wireless LAN systems are improved versions of the 802.11be system and meet backward compatibility requirements with the 802.11be system.

[0377] Figure 40 The example is performed at the transmitting STA, which can correspond to a beamforming transmitter or an access point (AP). Figure 40 The receiving STA can correspond to a beamforming receiver or at least one STA (station).

[0378] This embodiment proposes a method for an OBSS AP to perform an NDP probing procedure against a BSS STA, or a method for a BSS AP to perform an NDP probing procedure against an OBSS STA. Specifically, this embodiment proposes a method for setting an ID for a non-associated STA to provide feedback on information related to the OBSS channel or to receive feedback on information related to the OBSS channel.

[0379] In step S4010, the second transmitting station (STA) receives the first trigger frame from the first transmitting STA.

[0380] In step S4020, the second transmitting STA sends a Null Data Packet Advertisement (NDPA) frame to the receiving STA.

[0381] In step S4030, the second transmitting STA sends an NDP frame to the receiving STA.

[0382] In step S4040, the second transmitting STA receives a feedback frame based on the NDPA frame and the NDP frame from the receiving STA.

[0383] The receiving STA is a Basic Service Set (BSS) STA, the first transmitting STA is a BSS AP, and the second transmitting STA is an Overlapping Basic Service Set (OBSS) AP.

[0384] The first trigger frame includes information about the OBSS Association Identifier (OAID). The OAID is used by the second transmitting STA to identify the receiving STA. NDPA frames, NDP frames, and feedback frames are transmitted and received based on the OAID.

[0385] In other words, this embodiment proposes a method for setting OAID to perform a probe process for a receiving STA that is not associated with the second transmitting STA. This has the following effect: the BSS AP can obtain channel information for the neighboring AP (OBSS AP) of the BSS STA more accurately and quickly (or the OBSS AP can obtain channel information for the neighboring AP (BSS AP) of the OBSS STA), thereby enabling more efficient multi-AP operations (especially coordinated beamforming (C-BF) or joint transmission (J-TX), etc.).

[0386] OAID negotiation can be performed between the first transmitting STA and the receiving STA. This OAID negotiation can be performed before the first trigger frame is sent. In other words, OAID negotiation is a preparatory process that must be performed before the OBSS probe procedure begins. Afterwards, the OAID information can be shared with the second transmitting STA.

[0387] The first trigger frame may include a first sender address (TA) field and a first receiver address (RA) field. The first TA field may include a basic service set identifier (BSSID) for the first sending STA. The first RA field may be set to a broadcast address and includes a first indicator field. The first indicator field may include information about whether the first trigger frame is a frame used for probing between a second sending STA and a receiving STA.

[0388] The information related to OAID may include the ID information of the second transmitting STA. The ID information of the second transmitting STA may include the BSSID, BSS color, or BSS index of the multi-AP group. The second transmitting STA can transmit NDPA and NDP frames based on the OAID. A second transmitting STA that has confirmed its own ID information from the information related to OAID can prepare to transmit NDPA and NDP frames.

[0389] The receiving STA can be identified as a BSS STA that will receive NDPA and NDP frames based on OAID.

[0390] The first trigger frame may include allocation information for transmission opportunities (TXOPs) or service periods (SPs) for sending and receiving NDPA frames, NDP frames, and feedback frames. If the first trigger frame is a Multi-User Request to Transmit (MU-RTS) trigger frame, the SP duration of the limited target wake-up time (r-TWT) can be set for sending and receiving NDPA frames, NDP frames, and feedback frames.

[0391] Additionally, the first trigger frame may include a first TA field, a first RA field, and a public information field, but may exclude the user information field. In this case, the trigger-related public information subfield within the public information field can be defined as including the OBSSID and the AID or OAID of the BSS STA that will participate in the OBSS probe process. Other subfields within the public information field can be retained.

[0392] An NDPA frame may include a second TA field, a second RA field, and an AID11 subfield. The second TA field may include the BSSID of the second transmitting STA. The second RA field may be set to a broadcast address, or it may include a BSSID specifically assigned for probes between the second transmitting STA and the receiving STA. The AID11 subfield may be set to OAID.

[0393] The second transmitting STA can send a second trigger frame to the receiving STA. Since there are multiple receiving STAs, the second trigger frame can be a Beamforming Report Polling (BFRP) trigger frame used to set the resources to be fed back. The feedback frame can include information about the OBSS channel between the second transmitting STA and the receiving STA.

[0394] When multiple OBSS APs exist, the above OBSS probing process can be performed sequentially using NDP probing. Assume that the multiple OBSS APs include not only the second transmitting STA but also a third transmitting STA (another OBSS AP).

[0395] The third transmitting STA can receive the third trigger frame from the first transmitting STA. The third transmitting STA can send a (separate) NDPA frame to the receiving STA. The third transmitting STA can send a (separate) NDP frame to the receiving STA. The third transmitting STA can receive a (separate) feedback frame based on the NDPA frame and the NDP frame from the receiving STA.

[0396] The third trigger frame may include information for a (separate) OAID. This OAID can be information used by the third transmitting STA to identify the receiving STA. NDPA frames, NDP frames, and feedback frames can be sent and received based on this OAID.

[0397] The third trigger frame may include allocation information for TXOPs or SPs used (between the third transmitting STA and the receiving STA) to transmit and receive NDPA frames, NDP frames, and feedback frames.

[0398] In other words, an OBSS probe can be performed between the second transmitting STA and the receiving STA during the duration allocated by the first trigger frame, and an OBSS probe can be performed between the third transmitting STA and the receiving STA during the duration allocated by the third trigger frame. The duration allocated by the third trigger frame can be set after the duration allocated by the first trigger frame. Alternatively, the duration allocated by the third trigger frame can be set within the duration allocated by the first trigger frame.

[0399] NDP frames can be defined as a variant of an Ultra High Throughput (EHT) Multi-User (MU) PPDU or a variant of an UHR MU PPDU.

[0400] Figure 41 This is a flowchart illustrating the process of performing OBSS detection for BSS STA and OBSS AP according to this embodiment.

[0401] Figure 41 The example can be implemented in network environments that support next-generation wireless LAN systems (Ultra-High Reliability (UHR) wireless LAN systems or next-generation Wi-Fi). Next-generation wireless LAN systems are improved versions of the 802.11be system and meet backward compatibility requirements with the 802.11be system.

[0402] Figure 41 The example is performed at the receiving STA, which may correspond to a beamforming receiver or at least one STA (station). Figure 41 The transmitting STA can correspond to a beamforming transmitter or an AP (access point).

[0403] This embodiment proposes a method for an OBSS AP to perform an NDP probing procedure against a BSS STA, or a method for a BSS AP to perform an NDP probing procedure against an OBSS STA. Specifically, this embodiment proposes a method for setting an ID for a non-associated STA to provide feedback on information related to the OBSS channel or to receive feedback on information related to the OBSS channel.

[0404] In step S4110, the receiving station (STA) receives the first trigger frame from the first transmitting STA.

[0405] In step S4120, the receiving STA receives a Null Data Packet Advertisement (NDPA) frame from the second transmitting STA.

[0406] In step S4130, the receiving STA receives an NDP frame from the second transmitting STA.

[0407] In step S4140, the receiving STA sends a feedback frame to the first transmitting STA or the second transmitting STA based on the NDPA frame and the NDP frame.

[0408] The receiving STA is a Basic Service Set (BSS) STA, the first transmitting STA is a BSS AP, and the second transmitting STA is an Overlapping Basic Service Set (OBSS) AP.

[0409] The first trigger frame includes information about the OBSS Association Identifier (OAID). The OAID is used by the second transmitting STA to identify the receiving STA. NDPA frames, NDP frames, and feedback frames are transmitted and received based on the OAID.

[0410] In other words, this embodiment proposes a method for setting OAID to perform a probing process for a receiving STA that is not associated with the second transmitting STA. This has the following effect: the BSS AP can obtain channel information for the neighboring AP (OBSS AP) of the BSS STA more accurately and quickly (or the OBSS AP can obtain channel information for the neighboring AP (BSS AP) of the OBSS STA), thereby enabling more efficient multi-AP operations (especially coordinated beamforming (C-BF) or joint transmission (J-TX), etc.).

[0411] OAID negotiation can be performed between the first transmitting STA and the receiving STA. This OAID negotiation can be performed before the first trigger frame is sent. In other words, OAID negotiation is a preparatory process that must be performed before the OBSS probe procedure begins. Afterwards, the OAID information can be shared with the second transmitting STA.

[0412] The first trigger frame may include a first sender address (TA) field and a first receiver address (RA) field. The first TA field may include a basic service set identifier (BSSID) for the first sending STA. The first RA field may be set to a broadcast address and includes a first indicator field. The first indicator field may include information about whether the first trigger frame is a frame used for probing between a second sending STA and a receiving STA.

[0413] The information related to OAID may include the ID information of the second transmitting STA. The ID information of the second transmitting STA may include the BSSID, BSS color, or BSS index of the multi-AP group. The second transmitting STA can transmit NDPA and NDP frames based on the OAID. A second transmitting STA that has confirmed its own ID information from the information related to OAID can prepare to transmit NDPA and NDP frames.

[0414] The receiving STA can be identified as a BSS STA that will receive NDPA and NDP frames based on OAID.

[0415] The first trigger frame may include allocation information for transmission opportunities (TXOPs) or service periods (SPs) for sending and receiving NDPA frames, NDP frames, and feedback frames. If the first trigger frame is a Multi-User Request to Transmit (MU-RTS) trigger frame, the SP duration of the limited target wake-up time (r-TWT) can be set for sending and receiving NDPA frames, NDP frames, and feedback frames.

[0416] Additionally, the first trigger frame may include a first TA field, a first RA field, and a public information field, but may exclude the user information field. In this case, the trigger-related public information subfield within the public information field can be defined as including the OBSSID and the AID or OAID of the BSS STA that will participate in the OBSS probe process. Other subfields within the public information field can be retained.

[0417] An NDPA frame may include a second TA field, a second RA field, and an AID11 subfield. The second TA field may include the BSSID of the second transmitting STA. The second RA field may be set to a broadcast address, or may include a BSSID specifically assigned for probes between the second transmitting STA and the receiving STA. The AID11 subfield may be set to OAID.

[0418] The second transmitting STA can send a second trigger frame to the receiving STA. Since there are multiple receiving STAs, the second trigger frame can be a Beamforming Report Polling (BFRP) trigger frame used to set the resources to be fed back. The feedback frame can include information about the OBSS channel between the second transmitting STA and the receiving STA.

[0419] When multiple OBSS APs exist, the above OBSS probing process can be performed sequentially using NDP probing. Assume that the multiple OBSS APs include not only the second transmitting STA but also a third transmitting STA (another OBSS AP).

[0420] The third transmitting STA can receive the third trigger frame from the first transmitting STA. The third transmitting STA can send a (separate) NDPA frame to the receiving STA. The third transmitting STA can send a (separate) NDP frame to the receiving STA. The third transmitting STA can receive a (separate) feedback frame based on the NDPA frame and the NDP frame from the receiving STA.

[0421] The third trigger frame can be for information including a (separate) OAID. This OAID can be information used by the third transmitting STA to identify the receiving STA. NDPA frames, NDP frames, and feedback frames can be sent and received based on this OAID.

[0422] The third trigger frame may include allocation information for TXOPs or SPs used (between the third transmitting STA and the receiving STA) to transmit and receive NDPA frames, NDP frames, and feedback frames.

[0423] In other words, an OBSS probe can be performed between the second transmitting STA and the receiving STA during the duration allocated by the first trigger frame, and an OBSS probe can be performed between the third transmitting STA and the receiving STA during the duration allocated by the third trigger frame. The duration allocated by the third trigger frame can be set after the duration allocated by the first trigger frame. Alternatively, the duration allocated by the third trigger frame can be set within the duration allocated by the first trigger frame.

[0424] NDP frames can be defined as a variant of an Ultra High Throughput (EHT) Multi-User (MU) PPDU or a variant of an UHR MU PPDU.

[0425] <Device Configuration>

[0426] The technical features of this disclosure can be applied to various apparatuses and methods. For example, the technical features of this disclosure can be used by... Figure 1 and / or Figure 13 The device is used to perform / support this. For example, the technical features of this disclosure can be applied only to... Figure 1 and / or Figure 13 Part of it. For example, the technical features of this disclosure may be based on Figure 1 The processing chips 114 and 124 are used to implement this, or it can be implemented based on processors 111 and 121 and memory 112 and 122, or based on... Figure 13 The processor 610 and memory 620 are used for implementation. For example, the apparatus according to this disclosure receives a first trigger frame from a first transmitting station (STA); receives a null data packet announcement (NDPA) frame from a second transmitting STA; receives an NDP frame from the second transmitting STA; and transmits a feedback frame to the first transmitting STA or the second transmitting STA based on the NDPA frame and the NDP frame.

[0427] The technical features of this disclosure can be implemented based on a computer-readable medium (CRM). For example, the CRM according to this disclosure is at least one computer-readable medium that includes instructions designed to be executed by at least one processor.

[0428] The CRM can store instructions for performing operations, including: receiving a first trigger frame from a first transmitting station (STA); receiving a null data packet advertisement (NDPA) frame from a second transmitting STA; receiving an NDP frame from the second transmitting STA; and sending a feedback frame to either the first or second transmitting STA based on the NDPA and NDP frames. At least one processor can execute the instructions stored in the CRM according to this disclosure. The at least one processor associated with the CRM of this disclosure may be... Figure 1 Processors 111, 121, Figure 1 Processing chips 114, 124 or Figure 13 The processor 610. Furthermore, the CRM disclosed herein can be... Figure 1 Memory 112, 122, Figure 13 The memory 620 or a separate external memory / storage medium / disk.

[0429] The technical features described above are applicable to various applications or business models. For example, these technical features can be applied to wireless communication in devices that support artificial intelligence (AI).

[0430] Artificial intelligence (AI) refers to the field of research concerning artificial intelligence or the methods for creating AI, while machine learning refers to the field of research concerning methods for defining and solving various problems within the field of AI. Machine learning is also defined as algorithms used to improve the performance of operations through continuous experience.

[0431] Artificial neural networks (ANNs) are models used in machine learning, and can refer to an overall problem-solving model consisting of artificial neurons (nodes) that form a network through the combination of synapses. An artificial neural network can be defined by the connection patterns between neurons in different layers, the learning process that updates model parameters, and the activation function that generates the output values.

[0432] An artificial neural network may include an input layer, an output layer, and optionally one or more hidden layers. Each layer includes one or more neurons, and the artificial neural network may include synapses connecting the neurons. In an artificial neural network, each neuron can output the value of an activation function that takes the input signal, weights, and biases as input through the synapse.

[0433] Model parameters refer to the parameters determined through learning, and include the weights of synaptic connections and the biases of neurons. Hyperparameters refer to the parameters that are set before learning in a machine learning algorithm, and include the learning rate, number of iterations, mini-batch size, and initialization function.

[0434] The learning process of artificial neural networks can aim to determine the model parameters used to minimize the loss function. The loss function can be used as a metric for determining the optimal model parameters during the learning process of artificial neural networks.

[0435] Machine learning can be classified into supervised learning, unsupervised learning, and reinforcement learning.

[0436] Supervised learning refers to the method of training an artificial neural network using labels given to the training data. These labels indicate the correct answer (or result value) the artificial neural network should infer when the training data is input. Unsupervised learning refers to the method of training an artificial neural network without giving labels to the training data. Reinforcement learning refers to the training method used to train an agent defined in an environment to select actions or sequences of actions to maximize the cumulative reward in each state.

[0437] In artificial neural networks, machine learning implemented using deep neural networks (DNNs) with multiple hidden layers is called deep learning, and deep learning is a part of machine learning. In the following text, machine learning will be interpreted as including deep learning.

[0438] The aforementioned technical features can be applied to wireless communication for robots.

[0439] A robot is a machine that uses its own capabilities to automatically process or run a given task. Specifically, a robot that has the ability to recognize its environment and make autonomous judgments to perform operations can be called an intelligent robot.

[0440] Robots can be classified according to their purpose or field, such as industrial robots, medical robots, home robots, and military robots. Robots may include actuators or drivers containing motors to perform various physical operations, such as moving robot joints. Furthermore, mobile robots may include wheels, brakes, propellers, etc., in their actuators to move on the ground or fly in the air.

[0441] The aforementioned technical features can be applied to devices that support extended reality.

[0442] Extended reality is collectively referred to as Virtual Reality (VR), Augmented Reality (AR), and Mixed Reality (MR). VR technology is a computer graphics technology that provides real-world objects and backgrounds only in CG images; AR technology is a computer graphics technology that provides virtual CG images on top of real object images; and MR technology is a computer graphics technology that provides virtual objects that are blended and combined with the real world.

[0443] MR (Mixed Reality) and AR (Augmented Reality) technologies are similar in that they display real and virtual objects together. However, in AR, virtual objects serve as a supplement to real objects, while in MR, virtual and real objects have equal status.

[0444] XR technology can be applied to head-mounted displays (HMDs), head-up displays (HUDs), mobile phones, tablets, laptops, desktop computers, TVs, digital signage, and more. Devices that utilize XR technology can be referred to as XR devices.

[0445] The claims described in this specification can be combined in various ways. For example, the technical features of the method claims can be combined to implement an apparatus, and the technical features of the apparatus claims can be combined to implement a method. Furthermore, the technical features of the method claims and the apparatus claims can be combined to implement an apparatus, and the technical features of the method claims and the apparatus claims can be combined to implement a method.

Claims

1. A method in a wireless local area network (WLAN) system, the method comprising the following steps: The receiving station (STA) receives the first trigger frame from the first transmitting station (STA); The receiving STA receives an NDPA (Notification of Empty Data Packet) frame from the second transmitting STA. The receiving STA receives the NDP frame from the second transmitting STA; as well as The receiving STA sends a feedback frame to either the first transmitting STA or the second transmitting STA based on the NDPA frame and the NDP frame. Wherein, the receiving STA is a Basic Service Set (BSS) STA, the first transmitting STA is a BSS AP, and the second transmitting STA is an Overlapping Basic Service Set (OBSS) AP. The first trigger frame includes information about the OBSS associated identifier OAID. Wherein, the OAID is information used by the second transmitting STA to identify the receiving STA, and Specifically, the NDPA frame, the NDP frame, and the feedback frame are sent and received based on the OAID.

2. The method according to claim 1, further comprising the following steps: The receiving STA and the first sending STA perform negotiation for the OAID. Specifically, the negotiation for the OAID is performed before the first trigger frame is sent, and The information regarding the OAID is shared with the second transmitting STA.

3. The method according to claim 1, wherein, The first trigger frame includes a first sender address (TA) field and a first receiver address (RA) field. The first TA field includes the Basic Service Set Identifier (BSSID) of the first transmitting STA. The first RA field is set to the broadcast address and includes a first indicator field. The first indicator field includes information about whether the first trigger frame is a frame used for probing between the second transmitting STA and the receiving STA.

4. The method according to claim 1, wherein, The information regarding the OAID includes the ID information of the second transmitting STA. Specifically, the second transmitting STA transmits the NDPA frame and the NDP frame based on the OAID, and Specifically, the receiving STA is identified as a BSSSTA that will receive the NDPA frame and the NDP frame based on the OAID.

5. The method according to claim 1, wherein, The first trigger frame includes allocation information for transmission opportunities (TXOPs) or service periods (SPs) for sending and receiving the NDPA frame, the NDP frame, and the feedback frame.

6. The method according to claim 1, wherein, The NDPA frame includes a second TA field, a second RA field, and an AID11 subfield. The second TA field includes the BSSID of the second transmitting STA. Wherein, the second RA field is set to a broadcast address or includes a BSSID specifically assigned for probes between the second transmitting STA and the receiving STA, and The AID11 subfield is set to the OAID.

7. The method according to claim 1, further comprising: The receiving STA receives the second trigger frame from the second transmitting STA. Wherein, based on the fact that the receiving STA is multiple STAs, the second trigger frame is a Beamforming Report Polling (BFRP) trigger frame, the BFRP trigger frame being used to set the resources to be fed back, and The feedback frame includes information about the OBSS channel between the second transmitting STA and the receiving STA.

8. A receiving station (STA) in a wireless local area network (WLAN) system, the receiving STA comprising: Memory; transceiver; as well as A processor, operatively connected to the memory and the transceiver, The processor is configured as follows: Receive the first trigger frame from the first transmitting STA; Receive empty data packet announcement (NDPA) frames from the second transmitting STA; Receive NDP frames from the second transmitting STA; and Based on the NDPA frame and the NDP frame, a feedback frame is sent to the first transmitting STA or the second transmitting STA. Wherein, the receiving STA is a Basic Service Set (BSS) STA, the first transmitting STA is a BSS AP, and the second transmitting STA is an Overlapping Basic Service Set (OBSS) AP. The first trigger frame includes information about the OBSS associated identifier OAID. Wherein, the OAID is information used by the second transmitting STA to identify the receiving STA, and Specifically, the NDPA frame, the NDP frame, and the feedback frame are sent and received based on the OAID.

9. A method in a wireless local area network (WLAN) system, the method comprising the following steps: The second transmitting station (STA) receives the first trigger frame from the first transmitting station (STA); The second transmitting STA sends an NDPA (Notification of Empty Data Packet) frame to the receiving STA. The second transmitting STA sends an NDP frame to the receiving STA; as well as The second transmitting STA receives a feedback frame based on the NDPA frame and the NDP frame from the receiving STA. Wherein, the receiving STA is a Basic Service Set (BSS) STA, the first transmitting STA is a BSS AP, and the second transmitting STA is an Overlapping Basic Service Set (OBSS) AP. The first trigger frame includes information about the OBSS associated identifier OAID. Wherein, the OAID is information used by the second transmitting STA to identify the receiving STA, and Specifically, the NDPA frame, the NDP frame, and the feedback frame are sent and received based on the OAID.

10. The method according to claim 9, wherein, Negotiation for the OAID is performed between the first transmitting STA and the receiving STA. Specifically, the negotiation for the OAID is performed before the first trigger frame is sent, and The information regarding the OAID is shared with the second transmitting STA.

11. The method according to claim 9, wherein, The first trigger frame includes a first sender address (TA) field and a first receiver address (RA) field. The first TA field includes the Basic Service Set Identifier (BSSID) of the first transmitting STA. The first RA field is set to the broadcast address and includes a first indicator field. The first indicator field includes information about whether the first trigger frame is a frame used for probing between the second transmitting STA and the receiving STA.

12. The method according to claim 9, wherein, The information regarding the OAID includes the ID information of the second transmitting STA. Specifically, the second transmitting STA transmits the NDPA frame and the NDP frame based on the OAID, and Specifically, the receiving STA is identified as a BSSSTA that will receive the NDPA frame and the NDP frame based on the OAID.

13. The method according to claim 9, wherein, The first trigger frame includes allocation information for transmission opportunities (TXOPs) or service periods (SPs) for sending and receiving the NDPA frame, the NDP frame, and the feedback frame.

14. The method according to claim 9, wherein, The NDPA frame includes a second TA field, a second RA field, and an AID11 subfield. The second TA field includes the BSSID of the second transmitting STA. Wherein, the second RA field is set to a broadcast address or includes a BSSID specifically assigned for probes between the second transmitting STA and the receiving STA, and The AID11 subfield is set to the OAID.

15. The method according to claim 9, further comprising the following step: The second transmitting STA sends a second trigger frame to the receiving STA. Wherein, based on the fact that the receiving STA is multiple STAs, the second trigger frame is a Beamforming Report Polling (BFRP) trigger frame, the BFRP trigger frame being used to set the resources to be fed back, and The feedback frame includes information about the OBSS channel between the second transmitting STA and the receiving STA.

16. A second transmitting station STA in a wireless local area network (WLAN) system, the second transmitting STA comprising: Memory; transceiver; as well as A processor, operatively connected to the memory and the transceiver, The processor is configured as follows: Receive the first trigger frame from the first transmitting STA; Send an empty data packet announcement (NDPA) frame to the receiving STA; Send an NDP frame to the receiving STA; and The receiving STA receives a feedback frame based on the NDPA frame and the NDP frame. Wherein, the receiving STA is a Basic Service Set (BSS) STA, the first transmitting STA is a BSS AP, and the second transmitting STA is an Overlapping Basic Service Set (OBSS) AP. The first trigger frame includes information about the OBSS associated identifier OAID. Wherein, the OAID is information used by the second transmitting STA to identify the receiving STA, and Specifically, the NDPA frame, the NDP frame, and the feedback frame are sent and received based on the OAID.

17. A computer-readable medium comprising instructions executable by at least one processor to perform a method comprising the steps of: Receive the first trigger frame from the first transmitting station STA; Receive empty data packet announcement (NDPA) frames from the second transmitting STA; Receive NDP frames from the second transmitting STA; as well as Based on the NDPA frame and the NDP frame, a feedback frame is sent to the first transmitting STA or the second transmitting STA. Wherein, the receiving STA is a Basic Service Set (BSS) STA, the first transmitting STA is a BSS AP, and the second transmitting STA is an Overlapping Basic Service Set (OBSS) AP. The first trigger frame includes information about the OBSS associated identifier OAID. Wherein, the OAID is information used by the second transmitting STA to identify the receiving STA, and Specifically, the NDPA frame, the NDP frame, and the feedback frame are sent and received based on the OAID.

18. An apparatus in a wireless local area network (WLAN) system, the apparatus comprising: Memory; as well as A processor, operatively connected to the memory, The processor is configured as follows: Receive the first trigger frame from the first transmitting station STA; Receive empty data packet announcement (NDPA) frames from the second transmitting STA; Receive NDP frames from the second transmitting STA; and Based on the NDPA frame and the NDP frame, a feedback frame is sent to the first transmitting STA or the second transmitting STA. Wherein, the receiving STA is a Basic Service Set (BSS) STA, the first transmitting STA is a BSS AP, and the second transmitting STA is an Overlapping Basic Service Set (OBSS) AP. The first trigger frame includes information about the OBSS associated identifier OAID. Wherein, the OAID is information used by the second transmitting STA to identify the receiving STA, and Specifically, the NDPA frame, the NDP frame, and the feedback frame are sent and received based on the OAID.

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