WO2023128642A1 - Sensing measurement method and device in wireless lan system - Google Patents

Abstract

A sensing measurement method and device in a wireless LAN system are disclosed. A method by which a first station (STA) performs a sounding phase in a wireless LAN system, according to one embodiment of the present disclosure, may comprise the steps of: transmitting, to one or more second STAs, information related to the order of one or more sounding phases in a trigger based (TB) sensing measurement instance; and performing the one or more sounding phases on the basis of the information in the TB sensing measurement instance. The information can be transmitted through a trigger frame in the TB sensing measurement instance.

Description

Sensing measurement method and apparatus in wireless LAN system

The present disclosure relates to sensing in a wireless local area network (WLAN) system, and more particularly, to a sensing measurement method and apparatus in a wireless LAN system.

New technologies have been introduced to improve transmission rates, increase bandwidth, improve reliability, reduce errors, and reduce latency for a wireless local area network (WLAN). Among wireless LAN technologies, an Institute of Electrical and Electronics Engineers (IEEE) 802.11 series standard may be referred to as Wi-Fi. For example, technologies recently introduced to wireless LANs include enhancements for VHT (Very High-Throughput) of the 802.11ac standard, and enhancements for HE (High Efficiency) of the IEEE 802.11ax standard. do.

An improvement technique for providing sensing for a device using a WLAN signal (ie, WLAN sensing) is being discussed. For example, in the IEEE 802.11 task group (task group, TG) bf, an object (eg, a person, Standard technology development for performing sensing on objects, etc.) is in progress. Object sensing based on a WLAN signal has the advantage of being able to utilize an existing frequency band and having a lower possibility of invasion of privacy compared to existing sensing technologies. As the frequency range used in WLAN technology increases, precise sensing information can be obtained, and along with this, technology for reducing power consumption to efficiently support precise sensing procedures is being studied.

A technical problem of the present disclosure is to provide a measurement method and apparatus related to sensing in a wireless LAN system.

An additional technical problem of the present disclosure is to provide a method and apparatus for reducing ambiguity and performing efficient sensing measurement by sharing information on the configuration of a sensing measurement instance in a WLAN system.

The technical problems to be achieved in the present disclosure are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below. You will be able to.

A method performed by a first station (STA) in a wireless LAN system according to an aspect of the present disclosure includes information related to an order of one or more sounding phases in a trigger based (TB) sensing measurement instance. Transmitting the above to the second STA; and performing the one or more sounding phases based on information related to the order within the TB sensing measurement instance. Information related to the order may be transmitted through a trigger frame within the TB sensing measurement instance.

A method performed by a second station (STA) in a wireless LAN system according to an additional aspect of the present disclosure provides information related to an order of one or more sounding phases in a trigger based (TB) sensing measurement instance. Receiving from 1 STA; and performing the one or more sounding phases based on information related to the order within the TB sensing measurement instance. Information related to the order may be received through a trigger frame within the TB sensing measurement instance.

According to the present disclosure, a measurement method and apparatus related to sensing in a wireless LAN system may be provided.

According to the present disclosure, a method and apparatus for reducing ambiguity and performing efficient sensing measurement by sharing information on the configuration of a sensing measurement instance in a WLAN system may be provided.

Effects obtainable in the present disclosure are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below. .

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included as part of the detailed description to aid understanding of the present disclosure, provide embodiments of the present disclosure and, together with the detailed description, describe technical features of the present disclosure.

1 illustrates a block configuration diagram of a wireless communication device according to an embodiment of the present disclosure.

2 is a diagram illustrating an exemplary structure of a WLAN system to which the present disclosure may be applied.

3 is a diagram for explaining a link setup process to which the present disclosure may be applied.

4 is a diagram for explaining a backoff process to which the present disclosure may be applied.

5 is a diagram for explaining a frame transmission operation based on CSMA/CA to which the present disclosure may be applied.

6 is a diagram for explaining an example of a frame structure used in a WLAN system to which the present disclosure can be applied.

7 is a diagram illustrating examples of PPDUs defined in the IEEE 802.11 standard to which the present disclosure may be applied.

8 to 10 are diagrams for explaining examples of resource units of a WLAN system to which the present disclosure can be applied.

11 shows an exemplary structure of a HE-SIG-B field.

12 is a diagram for explaining a MU-MIMO method in which a plurality of users/STAs are allocated to one RU.

13 shows an example of a PPDU format to which the present disclosure can be applied.

14 is a diagram for explaining a HE Non-TB/TB sounding procedure to which the present disclosure may be applied.

15 is a diagram for explaining examples of available windows in a trigger-based ranging exchange process to which the present disclosure can be applied.

16 shows an exemplary format of a trigger frame to which the present disclosure may be applied.

17 is a diagram illustrating a configuration example of a TB sensing measurement instance to which the present disclosure may be applied.

18 is a diagram illustrating an example of a TF sounding phase to which the present disclosure may be applied.

19 is a diagram illustrating an example of an NDPA sounding phase to which the present disclosure may be applied.

20 is a diagram illustrating an example of a method of performing a sounding phase by a first STA according to the present disclosure.

21 is a diagram illustrating an example of a method of performing a sounding phase by a second STA according to the present disclosure.

22 is a diagram illustrating an example of a trigger dependent common information subfield format in a sensing trigger frame according to the present disclosure.

Hereinafter, preferred embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description set forth below in conjunction with the accompanying drawings is intended to describe exemplary embodiments of the present disclosure, and is not intended to represent the only embodiments in which the present disclosure may be practiced. The following detailed description includes specific details for the purpose of providing a thorough understanding of the present disclosure. However, one skilled in the art recognizes that the present disclosure may be practiced without these specific details.

In some cases, in order to avoid obscuring the concept of the present disclosure, well-known structures and devices may be omitted or may be shown in block diagram form centering on core functions of each structure and device.

In the present disclosure, when a component is said to be "connected", "coupled" or "connected" to another component, this is not only a direct connection relationship, but also an indirect connection relationship between which another component exists. may also be included. Also in this disclosure, the terms "comprises" or "has" specify the presence of a stated feature, step, operation, element and/or component, but not one or more other features, steps, operations, elements, components and/or components. The presence or addition of groups of these is not excluded.

In the present disclosure, terms such as “first” and “second” are used only for the purpose of distinguishing one component from another component and are not used to limit the components, unless otherwise specified. The order or importance among them is not limited. Accordingly, within the scope of the present disclosure, a first component in one embodiment may be referred to as a second component in another embodiment, and similarly, a second component in one embodiment may be referred to as a first component in another embodiment. can also be called

Terminology used in this disclosure is for description of specific embodiments and is not intended to limit the scope of the claims. As used in the description of the embodiments and the appended claims, the singular forms are intended to include the plural forms as well unless the context clearly dictates otherwise. As used in this disclosure, the term “and/or” may refer to any one of the associated listed items, or is meant to refer to and include any and all possible combinations of two or more of them. Also, in this disclosure, “/” between words has the same meaning as “and/or” unless otherwise stated.

Examples of the present disclosure may be applied to various wireless communication systems. For example, examples of the present disclosure may be applied to a wireless LAN system. For example, examples of the present disclosure may be applied to an IEEE 802.11a/g/n/ac/ax standards-based wireless LAN. Furthermore, examples of the present disclosure may be applied to a wireless LAN based on the newly proposed IEEE 802.11be (or EHT) standard. Examples of the present disclosure may be applied to a wireless LAN based on the IEEE 802.11be Release-2 standard corresponding to an additional improvement technology of the IEEE 802.11be Release-1 standard. Additionally, examples of the present disclosure may be applied to a next-generation standards-based wireless LAN after IEEE 802.11be. Further, examples of this disclosure may be applied to a cellular wireless communication system. For example, it can be applied to a cellular wireless communication system based on Long Term Evolution (LTE)-based technology and 5G New Radio (NR)-based technology of the 3rd Generation Partnership Project (3GPP) standard.

Hereinafter, technical features to which examples of the present disclosure may be applied will be described.

1 illustrates a block configuration diagram of a wireless communication device according to an embodiment of the present disclosure.

The first device 100 and the second device 200 illustrated in FIG. 1 are a terminal, a wireless device, a wireless transmit receive unit (WTRU), a user equipment (UE), and a mobile station (MS). ), UT (user terminal), MSS (Mobile Subscriber Station), MSS (Mobile Subscriber Unit), SS (Subscriber Station), AMS (Advanced Mobile Station), WT (Wireless terminal), or simply user. term can be replaced. In addition, the first device 100 and the second device 200 include an access point (AP), a base station (BS), a fixed station, a Node B, a base transceiver system (BTS), a network, It can be replaced with various terms such as AI (Artificial Intelligence) system, RSU (road side unit), repeater, router, relay, and gateway.

The devices 100 and 200 illustrated in FIG. 1 may also be referred to as stations (STAs). For example, the devices 100 and 200 illustrated in FIG. 1 may be referred to by various terms such as a transmitting device, a receiving device, a transmitting STA, and a receiving STA. For example, the STAs 110 and 200 may perform an access point (AP) role or a non-AP role. That is, in the present disclosure, the STAs 110 and 200 may perform functions of an AP and/or a non-AP. When the STAs 110 and 200 perform an AP function, they may be simply referred to as APs, and when the STAs 110 and 200 perform non-AP functions, they may be simply referred to as STAs. Also, in the present disclosure, an AP may also be indicated as an AP STA.

Referring to FIG. 1 , the first device 100 and the second device 200 may transmit and receive wireless signals through various wireless LAN technologies (eg, IEEE 802.11 series). The first device 100 and the second device 200 may include an interface for a medium access control (MAC) layer and a physical layer (PHY) conforming to the IEEE 802.11 standard.

In addition, the first device 100 and the second device 200 may additionally support various communication standards (eg, 3GPP LTE series, 5G NR series standards, etc.) technologies other than wireless LAN technology. In addition, the device of the present disclosure may be implemented in various devices such as a mobile phone, a vehicle, a personal computer, augmented reality (AR) equipment, and virtual reality (VR) equipment. In addition, the STA of the present specification includes voice call, video call, data communication, autonomous-driving, machine-type communication (MTC), machine-to-machine (M2M), device-to-device (D2D), Various communication services such as IoT (Internet-of-Things) may be supported.

The first device 100 includes one or more processors 102 and one or more memories 104, and may additionally include one or more transceivers 106 and/or one or more antennas 108. The processor 102 controls the memory 104 and/or the transceiver 106 and may be configured to implement the descriptions, functions, procedures, suggestions, methods and/or flowcharts of operations set forth in this disclosure. For example, the processor 102 may process information in the memory 104 to generate first information/signal, and transmit a radio signal including the first information/signal through the transceiver 106 . In addition, the processor 102 may receive a radio signal including the second information/signal through the transceiver 106, and then store information obtained from signal processing of the second information/signal in the memory 104. The memory 104 may be connected to the processor 102 and may store various information related to the operation of the processor 102 . For example, memory 104 may perform some or all of the processes controlled by processor 102, or instructions for performing the descriptions, functions, procedures, suggestions, methods, and/or operational flowcharts disclosed in this disclosure. (instructions) may be stored. Here, the processor 102 and the memory 104 may be part of a communication modem/circuit/chip designed to implement a wireless LAN technology (eg, IEEE 802.11 series). The transceiver 106 may be coupled to the processor 102 and may transmit and/or receive wireless signals via one or more antennas 108 . The transceiver 106 may include a transmitter and/or a receiver. The transceiver 106 may be used interchangeably with a radio frequency (RF) unit. In the present disclosure, a device may mean a communication modem/circuit/chip.

The second device 200 includes one or more processors 202, one or more memories 204, and may further include one or more transceivers 206 and/or one or more antennas 208. The processor 202 controls the memory 204 and/or the transceiver 206 and may be configured to implement the descriptions, functions, procedures, suggestions, methods and/or flowcharts of operations set forth in this disclosure. For example, the processor 202 may process information in the memory 204 to generate third information/signal, and transmit a radio signal including the third information/signal through the transceiver 206 . In addition, the processor 202 may receive a radio signal including the fourth information/signal through the transceiver 206 and store information obtained from signal processing of the fourth information/signal in the memory 204 . The memory 204 may be connected to the processor 202 and may store various information related to the operation of the processor 202 . For example, memory 204 may perform some or all of the processes controlled by processor 202, or instructions for performing the descriptions, functions, procedures, suggestions, methods, and/or flowcharts of operations disclosed in this disclosure. It may store software codes including them. Here, the processor 202 and the memory 204 may be part of a communication modem/circuit/chip designed to implement a wireless LAN technology (eg, IEEE 802.11 series). The transceiver 206 may be coupled to the processor 202 and may transmit and/or receive wireless signals via one or more antennas 208 . The transceiver 206 may include a transmitter and/or a receiver. The transceiver 206 may be used interchangeably with an RF unit. In the present disclosure, a device may mean a communication modem/circuit/chip.

Hereinafter, hardware elements of the devices 100 and 200 will be described in more detail. Although not limited to this, one or more protocol layers may be implemented by one or more processors 102, 202. For example, one or more processors 102, 202 may implement one or more layers (eg, functional layers such as PHY, MAC). One or more processors (102, 202) may generate one or more Protocol Data Units (PDUs) and/or one or more Service Data Units (SDUs) in accordance with the descriptions, functions, procedures, proposals, methods and/or operational flow charts disclosed herein. can create

One or more processors 102, 202 may generate messages, control information, data or information in accordance with the descriptions, functions, procedures, proposals, methods and/or operational flow diagrams set forth in this disclosure. One or more processors 102, 202 may process PDUs, SDUs, messages, control information, data or signals containing information (e.g., baseband signals) according to the functions, procedures, proposals and/or methods disclosed herein. generated and provided to one or more transceivers (106, 206). One or more processors 102, 202 may receive signals (e.g., baseband signals) from one or more transceivers 106, 206, the descriptions, functions, procedures, suggestions, methods and/or described in this disclosure. PDUs, SDUs, messages, control information, data or information may be acquired according to the operational flowcharts.

One or more processors 102, 202 may be referred to as a controller, microcontroller, microprocessor or microcomputer. One or more processors 102, 202 may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Digital Signal Processing Devices (DSPDs), one or more Programmable Logic Devices (PLDs), or one or more Field Programmable Gate Arrays (FPGAs). may be included in one or more processors 102 and 202. The descriptions, functions, procedures, proposals, methods and/or operational flow charts disclosed in this disclosure may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, and the like. Firmware or software configured to perform the descriptions, functions, procedures, suggestions, methods and/or operational flow diagrams disclosed in this disclosure may be included in one or more processors (102, 202) or stored in one or more memories (104, 204). It can be driven by the above processors 102 and 202. The descriptions, functions, procedures, suggestions, methods and/or operational flow diagrams disclosed in this disclosure may be implemented using firmware or software in the form of codes, instructions and/or sets of instructions.

One or more memories 104, 204 may be coupled with one or more processors 102, 202 and may store various types of data, signals, messages, information, programs, codes, instructions and/or instructions. One or more memories 104, 204 may be comprised of ROM, RAM, EPROM, flash memory, hard drives, registers, cache memory, computer readable storage media, and/or combinations thereof. One or more memories 104, 204 may be located internally and/or external to one or more processors 102, 202. Additionally, one or more memories 104, 204 may be coupled to one or more processors 102, 202 through various technologies, such as wired or wireless connections.

One or more transceivers 106, 206 may transmit user data, control information, radio signals/channels, etc., as referred to in the methods and/or operational flow charts of this disclosure, to one or more other devices. The one or more transceivers 106, 206 may receive user data, control information, radio signals/channels, etc. referred to in the descriptions, functions, procedures, proposals, methods and/or operational flow charts, etc. disclosed in this disclosure from one or more other devices. there is. For example, one or more transceivers 106 and 206 may be connected to one or more processors 102 and 202 and transmit and receive wireless signals. For example, one or more processors 102, 202 may control one or more transceivers 106, 206 to transmit user data, control information, or radio signals to one or more other devices. Additionally, one or more processors 102, 202 may control one or more transceivers 106, 206 to receive user data, control information, or radio signals from one or more other devices. In addition, one or more transceivers 106, 206 may be coupled with one or more antennas 108, 208, and one or more transceivers 106, 206 may be connected to one or more antennas 108, 208, as described herein. , procedures, proposals, methods and / or operation flowcharts, etc. can be set to transmit and receive user data, control information, radio signals / channels, etc. In the present disclosure, one or more antennas may be a plurality of physical antennas or a plurality of logical antennas (eg, antenna ports). One or more transceivers (106, 206) convert the received radio signals/channels from RF band signals in order to process the received user data, control information, radio signals/channels, etc. using one or more processors (102, 202). It can be converted into a baseband signal. One or more transceivers 106 and 206 may convert user data, control information, and radio signals/channels processed by one or more processors 102 and 202 from baseband signals to RF band signals. To this end, one or more of the transceivers 106, 206 may include (analog) oscillators and/or filters.

For example, one of the STAs 100 and 200 may perform an intended operation of an AP, and the other of the STAs 100 and 200 may perform an intended operation of a non-AP STA. For example, the transceivers 106 and 206 of FIG. 1 transmit and receive signals (eg, packets conforming to IEEE 802.11a/b/g/n/ac/ax/be or PPDU (Physical Layer Protocol Data Unit)). action can be performed. In addition, in the present disclosure, an operation in which various STAs generate transmission/reception signals or perform data processing or calculation in advance for transmission/reception signals may be performed by the processors 102 and 202 of FIG. 1 .

For example, an example of an operation of generating a transmission/reception signal or performing data processing or calculation in advance for the transmission/reception signal is, 1) a field included in the PPDU (SIG (signal), STF (short training field), LTF (long training field), Data, etc.) operation of determining/acquiring/constructing/operating/decoding/encoding, 2) time resource or frequency used for fields (SIG, STF, LTF, Data, etc.) included in the PPDU Operation of determining/constructing/acquiring resources (eg, subcarrier resources), etc. 3) Specific sequences (eg, pilot sequences) used for fields (SIG, STF, LTF, Data, etc.) included in the PPDU , STF/LTF sequence, extra sequence applied to SIG), etc., 4) power control operation and/or power saving operation applied to the STA, 5) determination/acquisition/configuration of ACK signal It may include operations related to / calculation / decoding / encoding. In addition, in the following example, various information (eg, information related to fields / subfields / control fields / parameters / power, etc.) used by various STAs to determine / acquire / configure / calculate / decode / encode transmission and reception signals may be stored in the memories 104 and 204 of FIG. 1 .

Hereinafter, downlink (DL) refers to a link for communication from an AP STA to a non-AP STA, and a downlink PPDU/packet/signal may be transmitted and received through the downlink. In downlink communication, a transmitter may be part of an AP STA, and a receiver may be part of a non-AP STA. Uplink (UL) refers to a link for communication from non-AP STAs to AP STAs, and UL PPDUs/packets/signals may be transmitted and received through uplink. In uplink communication, a transmitter may be part of a non-AP STA, and a receiver may be part of an AP STA.

2 is a diagram illustrating an exemplary structure of a WLAN system to which the present disclosure may be applied.

The structure of the WLAN system may be composed of a plurality of components. A wireless LAN supporting STA mobility transparent to an upper layer may be provided by interaction of a plurality of components. A Basic Service Set (BSS) corresponds to a basic building block of a wireless LAN. In FIG. 2, there are two BSSs (BSS1 and BSS2), and two STAs are included as members of each BSS (STA1 and STA2 are included in BSS1, and STA3 and STA4 are included in BSS2) by way of example. show An ellipse representing a BSS in FIG. 2 may also be understood as representing a coverage area in which STAs included in the corresponding BSS maintain communication. This area may be referred to as a Basic Service Area (BSA). When an STA moves out of the BSA, it cannot directly communicate with other STAs within the BSA.

If the DS shown in FIG. 2 is not considered, the most basic type of BSS in a wireless LAN is an independent BSS (Independent BSS, IBSS). For example, IBSS may have a minimal form consisting of only two STAs. For example, assuming that other components are omitted, BSS1 composed of only STA1 and STA2 or BSS2 composed of only STA3 and STA4 may respectively correspond to representative examples of IBSS. This configuration is possible when STAs can communicate directly without an AP. In addition, in this type of wireless LAN, it is not configured in advance, but may be configured when a LAN is required, and this may be referred to as an ad-hoc network. Since the IBSS does not include an AP, there is no centralized management entity. That is, in IBSS, STAs are managed in a distributed manner. In the IBSS, all STAs can be made up of mobile STAs, and access to the distributed system (DS) is not allowed, forming a self-contained network.

The STA's membership in the BSS may be dynamically changed by turning on or off the STA, entering or exiting the BSS area, and the like. To become a member of the BSS, the STA may join the BSS using a synchronization process. In order to access all services of the BSS infrastructure, the STA must be associated with the BSS. This association may be dynamically established and may include the use of a Distribution System Service (DSS).

Direct STA-to-STA distance in a WLAN may be limited by PHY performance. In some cases, this distance limit may be sufficient, but in some cases, communication between STAs at a longer distance may be required. A distributed system (DS) may be configured to support extended coverage.

DS means a structure in which BSSs are interconnected. Specifically, as shown in FIG. 2, a BSS may exist as an extended form of a network composed of a plurality of BSSs. DS is a logical concept and can be specified by the characteristics of Distributed System Media (DSM). In this regard, a wireless medium (WM) and a DSM may be logically separated. Each logical medium is used for a different purpose and is used by different components. These media are not limited to being the same, nor are they limited to being different. In this way, the flexibility of the WLAN structure (DS structure or other network structure) can be explained in that a plurality of media are logically different. That is, the WLAN structure may be implemented in various ways, and the corresponding WLAN structure may be independently specified by the physical characteristics of each embodiment.

A DS can support a mobile device by providing seamless integration of multiple BSSs and providing logical services needed to address addresses to destinations. In addition, the DS may further include a component called a portal that serves as a bridge for connection between the wireless LAN and other networks (eg, IEEE 802.X).

An AP means an entity that enables access to a DS through a WM for coupled non-AP STAs and also has the functionality of an STA. Data movement between the BSS and the DS may be performed through the AP. For example, STA2 and STA3 shown in FIG. 2 have the functionality of STAs, and provide a function allowing combined non-AP STAs (STA1 and STA4) to access the DS. Also, since all APs basically correspond to STAs, all APs are addressable entities. The address used by the AP for communication on the WM and the address used by the AP for communication on the DSM are not necessarily the same. A BSS composed of an AP and one or more STAs may be referred to as an infrastructure BSS.

Data transmitted from one of the STA(s) coupled to an AP to an STA address of that AP is always received on an uncontrolled port and may be processed by an IEEE 802.1X port access entity. In addition, when a controlled port is authenticated, transmission data (or frames) can be delivered to the DS.

An extended service set (ESS) may be set to provide wide coverage in addition to the above-described DS structure.

ESS refers to a network in which a network having an arbitrary size and complexity is composed of DS and BSS. An ESS may correspond to a set of BSSs connected to one DS. However, ESS does not include DS. An ESS network is characterized by being seen as an IBSS in the LLC (Logical Link Control) layer. STAs included in the ESS can communicate with each other, and mobile STAs can move from one BSS to another BSS (within the same ESS) transparently to the LLC. APs included in one ESS may have the same service set identification (SSID). The SSID is distinguished from the BSSID, which is an identifier of the BSS.

In the WLAN system, nothing is assumed about the relative physical locations of BSSs, and all of the following forms are possible. BSSs can partially overlap, which is a form commonly used to provide continuous coverage. Also, BSSs may not be physically connected, and logically there is no limit on the distance between BSSs. Also, the BSSs may be physically located in the same location, which may be used to provide redundancy. Also, one (or more than one) IBSS or ESS networks may physically exist in the same space as one (or more than one) ESS network. This is when an ad-hoc network operates in a location where an ESS network exists, when physically overlapping wireless networks are configured by different organizations, or when two or more different access and security policies are required in the same location. It may correspond to the form of an ESS network in the like.

3 is a diagram for explaining a link setup process to which the present disclosure may be applied.

In order for the STA to set up a link with respect to the network and transmit/receive data, it first discovers the network, performs authentication, establishes an association, and authenticates for security have to go through The link setup process may also be referred to as a session initiation process or a session setup process. In addition, the processes of discovery, authentication, association, and security setting of the link setup process may be collectively referred to as an association process.

In step S310, the STA may perform a network discovery operation. The network discovery operation may include a scanning operation of the STA. That is, in order for the STA to access the network, it needs to find a network in which it can participate. The STA must identify a compatible network before participating in a wireless network, and the process of identifying a network existing in a specific area is called scanning.

Scanning schemes include active scanning and passive scanning. FIG. 3 exemplarily illustrates a network discovery operation including an active scanning process. In active scanning, an STA performing scanning transmits a probe request frame to discover which APs exist around it while moving channels and waits for a response thereto. A responder transmits a probe response frame as a response to the probe request frame to the STA that has transmitted the probe request frame. Here, the responder may be an STA that last transmitted a beacon frame in the BSS of the channel being scanned. In the BSS, since the AP transmits the beacon frame, the AP becomes a responder. In the IBSS, the STAs in the IBSS rotate to transmit the beacon frame, so the responder is not constant. For example, an STA that transmits a probe request frame on channel 1 and receives a probe response frame on channel 1 stores BSS-related information included in the received probe response frame and transmits the probe request frame on the next channel (e.g., channel 2). channel), and scanning (ie, probe request/response transmission/reception on channel 2) can be performed in the same way.

Although not shown in FIG. 3, the scanning operation may be performed in a passive scanning manner. In passive scanning, an STA performing scanning waits for a beacon frame while moving channels. A beacon frame is one of the management frames defined in IEEE 802.11, and is periodically transmitted to notify the existence of a wireless network and to allow an STA performing scanning to find a wireless network and participate in the wireless network. In the BSS, the AP serves to transmit beacon frames periodically, and in the IBSS, STAs within the IBSS rotate to transmit beacon frames. When an STA performing scanning receives a beacon frame, it stores information about the BSS included in the beacon frame and records beacon frame information in each channel while moving to another channel. The STA receiving the beacon frame may store BSS-related information included in the received beacon frame, move to the next channel, and perform scanning in the next channel in the same way. Comparing active scanning and passive scanning, active scanning has an advantage of having less delay and less power consumption than passive scanning.

After the STA discovers the network, an authentication process may be performed in step S320. This authentication process may be referred to as a first authentication process in order to be clearly distinguished from the security setup operation of step S340 to be described later.

The authentication process includes a process in which the STA transmits an authentication request frame to the AP, and in response, the AP transmits an authentication response frame to the STA. An authentication frame used for authentication request/response corresponds to a management frame.

The authentication frame includes authentication algorithm number, authentication transaction sequence number, status code, challenge text, RSN (Robust Security Network), finite cyclic group Group), etc. This corresponds to some examples of information that may be included in the authentication request/response frame, and may be replaced with other information or additional information may be further included.

The STA may transmit an authentication request frame to the AP. The AP may determine whether to allow authentication of the corresponding STA based on information included in the received authentication request frame. The AP may provide the result of the authentication process to the STA through an authentication response frame.

After the STA is successfully authenticated, an association process may be performed in step S330. The association process includes a process in which the STA transmits an association request frame to the AP, and in response, the AP transmits an association response frame to the STA.

For example, the association request frame includes information related to various capabilities, beacon listen interval, service set identifier (SSID), supported rates, supported channels, RSN, mobility It may include information about domain, supported operating classes, TIM broadcast request (Traffic Indication Map Broadcast request), interworking service capability, and the like. For example, the combined response frame includes information related to various capabilities, status code, association ID (AID), supported rate, enhanced distributed channel access (EDCA) parameter set, received channel power indicator (RCPI), received signal to RSNI (received signal to Noise Indicator), mobility domain, timeout interval (e.g., association comeback time), overlapping BSS scan parameters, TIM broadcast response, Quality of Service (QoS) map, etc. can do. This corresponds to some examples of information that may be included in the association request/response frame, and may be replaced with other information or additional information may be further included.

After the STA has successfully joined the network, a security setup process may be performed in step S340. The security setup process of step S340 may be referred to as an authentication process through RSNA (Robust Security Network Association) request/response, and the authentication process of step S320 is referred to as a first authentication process, and the security setup process of step S340 may also simply be referred to as an authentication process.

The security setup process of step S340 may include, for example, a process of setting up a private key through 4-way handshaking through an Extensible Authentication Protocol over LAN (EAPOL) frame. . Also, the security setup process may be performed according to a security method not defined in the IEEE 802.11 standard.

4 is a diagram for explaining a backoff process to which the present disclosure may be applied.

In a WLAN system, a basic access mechanism of medium access control (MAC) is a carrier sense multiple access with collision avoidance (CSMA/CA) mechanism. The CSMA/CA mechanism is also called Distributed Coordination Function (DCF) of IEEE 802.11 MAC, and basically adopts a "listen before talk" access mechanism. According to this type of access mechanism, the AP and / or STA senses a radio channel or medium for a predetermined time interval (eg, DCF Inter-Frame Space (DIFS)) prior to starting transmission As a result of the sensing, if the medium is determined to be in an idle state, frame transmission is started through the corresponding medium, while the medium is occupied or If it is detected that it is busy, the corresponding AP and/or STA does not start its own transmission and waits by setting a delay period (eg, random backoff period) for medium access. Frame transmission may be attempted later, and since several STAs are expected to attempt frame transmission after waiting for different periods of time due to the application of the random backoff period, collision may be minimized.

In addition, the IEEE 802.11 MAC protocol provides a Hybrid Coordination Function (HCF). HCF is based on the DCF and Point Coordination Function (PCF). PCF is a polling-based synchronous access method and refers to a method in which all receiving APs and/or STAs periodically poll to receive data frames. In addition, HCF has Enhanced Distributed Channel Access (EDCA) and HCF Controlled Channel Access (HCCA). EDCA is a contention-based access method for a provider to provide data frames to multiple users, and HCCA uses a non-contention-based channel access method using a polling mechanism. In addition, the HCF includes a medium access mechanism for improving WLAN QoS (Quality of Service), and can transmit QoS data in both a Contention Period (CP) and a Contention Free Period (CFP). .

An operation based on a random backoff period will be described with reference to FIG. 4 . When the occupied/busy medium changes to an idle state, several STAs may attempt to transmit data (or frames). As a method for minimizing collisions, STAs may select a random backoff count and attempt transmission after waiting for a corresponding slot time. The random backoff count has a pseudo-random integer value and may be determined as one of values ranging from 0 to CW. Here, CW is a contention window parameter value. The CW parameter is given CWmin as an initial value, but may take a value twice as large in case of transmission failure (for example, when an ACK for the transmitted frame is not received). When the CW parameter value reaches CWmax, data transmission may be attempted while maintaining the CWmax value until data transmission is successful, and when data transmission is successful, the CWmin value is reset. The values of CW, CWmin and CWmax are preferably set to 2 ⁿ -1 (n = 0, 1, 2, ...).

When the random backoff process starts, the STA continuously monitors the medium while counting down the backoff slots according to the determined backoff count value. When the medium is monitored for occupancy, it stops counting down and waits, and resumes the rest of the countdown when the medium becomes idle.

In the example of FIG. 4 , when a packet to be transmitted arrives at the MAC of STA3, STA3 can transmit the frame immediately after confirming that the medium is idle as much as DIFS. The remaining STAs monitor and wait for the medium to be occupied/occupied. In the meantime, data to be transmitted may also occur in each of STA1, STA2, and STA5, and each STA waits as long as DIFS when the medium is monitored as idle, and then counts down the backoff slot according to the random backoff count value selected by each STA. can be performed. Assume that STA2 selects the smallest backoff count value and STA1 selects the largest backoff count value. That is, the case where the remaining back-off time of STA5 is shorter than the remaining back-off time of STA1 at the time when STA2 completes the back-off count and starts frame transmission is exemplified. STA1 and STA5 temporarily stop counting down and wait while STA2 occupies the medium. When the occupation of STA2 ends and the medium becomes idle again, STA1 and STA5 wait for DIFS and resume the stopped backoff count. That is, frame transmission may be started after counting down the remaining backoff slots for the remaining backoff time. Since the remaining backoff time of STA5 is shorter than that of STA1, STA5 starts frame transmission. While STA2 occupies the medium, data to be transmitted may also occur in STA4. From the standpoint of STA4, when the medium becomes idle, after waiting for as much as DIFS, the STA4 may perform a countdown according to the random backoff count value selected by the STA4 and start transmitting frames. The example of FIG. 4 shows a case where the remaining backoff time of STA5 coincides with the random backoff count value of STA4 by chance. In this case, a collision may occur between STA4 and STA5. When a collision occurs, both STA4 and STA5 do not receive an ACK, so data transmission fails. In this case, STA4 and STA5 may double the CW value, select a random backoff count value, and perform a countdown. STA1 waits while the medium is occupied due to transmission of STA4 and STA5, waits for DIFS when the medium becomes idle, and then starts frame transmission after the remaining backoff time has elapsed.

As in the example of FIG. 4, the data frame is a frame used for transmission of data forwarded to a higher layer, and may be transmitted after a backoff performed after DIFS elapses from when the medium becomes idle. Additionally, the management frame is a frame used for exchange of management information that is not forwarded to a higher layer, and is transmitted after a backoff performed after an IFS such as DIFS or Point Coordination Function IFS (PIFS). Beacon, association request/response, re-association request/response, probe request/response, authentication request/response as subtype frames of management frame. request/response), etc. A control frame is a frame used to control access to a medium. RTS (Request-To-Send), CTS (Clear-To-Send), ACK (Acknowledgment), PS-Poll (Power Save-Poll), block ACK (BlockAck), block ACK request ( BlockACKReq), NDP announcement (null data packet announcement), and trigger. If the control frame is not a response frame of the previous frame, it is transmitted after backoff performed after DIFS elapses, and if it is a response frame of the previous frame, it is transmitted without performing backoff after SIFS (short IFS) elapses. The type and subtype of the frame may be identified by a type field and a subtype field in a frame control (FC) field.

QoS (Quality of Service) STA is AIFS (arbitration IFS) for the access category (AC) to which the frame belongs, that is, AIFS[i] (where i is a value determined by AC) Backoff performed after elapsed After that, the frame can be transmitted. Here, the frame in which AIFS[i] can be used may be a data frame, a management frame, or a control frame other than a response frame.

5 is a diagram for explaining a frame transmission operation based on CSMA/CA to which the present disclosure may be applied.

As described above, the CSMA/CA mechanism includes virtual carrier sensing in addition to physical carrier sensing in which an STA directly senses a medium. Virtual carrier sensing is intended to compensate for problems that may occur in medium access, such as a hidden node problem. For virtual carrier sensing, the STA's MAC may use a Network Allocation Vector (NAV). NAV is a value that indicates to other STAs the remaining time until the medium is available for use by an STA currently using or having the right to use the medium. Accordingly, the value set as the NAV corresponds to a period in which the medium is scheduled to be used by the STA transmitting the frame, and the STA receiving the NAV value is prohibited from accessing the medium during the corresponding period. For example, the NAV may be set based on the value of the “duration” field of the MAC header of the frame.

In the example of FIG. 5 , it is assumed that STA1 intends to transmit data to STA2, and STA3 is in a position capable of overhearing some or all of frames transmitted and received between STA1 and STA2.

In order to reduce the possibility of transmission collision of multiple STAs in CSMA/CA based frame transmission operation, a mechanism using RTS/CTS frames may be applied. In the example of FIG. 5 , while transmission of STA1 is being performed, as a result of carrier sensing of STA3, it may be determined that the medium is in an idle state. That is, STA1 may correspond to a hidden node to STA3. Alternatively, in the example of FIG. 5 , it may be determined that the carrier sensing result medium of STA3 is in an idle state while transmission of STA2 is being performed. That is, STA2 may correspond to a hidden node to STA3. Before performing data transmission/reception between STA1 and STA2, an STA outside the transmission range of one of STA1 or STA2, or an STA outside the carrier sensing range for transmission from STA1 or STA3, transmits data between STA1 and STA2 through exchange of RTS/CTS frames. It is possible not to attempt to occupy a channel during data transmission and reception.

Specifically, STA1 may determine whether a channel is being used through carrier sensing. In terms of physical carrier sensing, STA1 may determine a channel occupation idle state based on an energy level or signal correlation detected in a channel. In addition, in terms of virtual carrier sensing, STA1 may use a network allocation vector (NAV) timer to determine a channel occupancy state.

STA1 may transmit an RTS frame to STA2 after performing a backoff when the channel is in an idle state during DIFS. When STA2 receives the RTS frame, it may transmit a CTS frame as a response to the RTS frame to STA1 after SIFS.

If STA3 cannot overhear the CTS frame from STA2, but can overhear the RTS frame from STA1, STA3 uses duration information included in the RTS frame to transmit frames continuously transmitted thereafter A NAV timer for (eg, SIFS + CTS frame + SIFS + data frame + SIFS + ACK frame) may be set. Alternatively, if STA3 can overhear a CTS frame from STA2 although STA3 cannot overhear an RTS frame from STA1, STA3 uses duration information included in the CTS frame to transmit frames that are subsequently transmitted continuously A NAV timer for a period (eg, SIFS + data frame + SIFS + ACK frame) may be set. That is, if STA3 can overhear one or more of the RTS or CTS frames from one or more of STA1 or STA2, it can set the NAV accordingly. When the STA3 receives a new frame before the NAV timer expires, the STA3 may update the NAV timer using duration information included in the new frame. STA3 does not attempt channel access until the NAV timer expires.

When STA1 receives the CTS frame from STA2, it may transmit a data frame to STA2 after SIFS from the time when reception of the CTS frame is completed. When the STA2 successfully receives the data frame, it may transmit an ACK frame as a response to the data frame to the STA1 after SIFS. STA3 may determine whether the channel is being used through carrier sensing when the NAV timer expires. When the STA3 determines that the channel is not used by other terminals during DIFS after expiration of the NAV timer, the STA3 may attempt channel access after a contention window (CW) according to a random backoff has passed.

6 is a diagram for explaining an example of a frame structure used in a WLAN system to which the present disclosure can be applied.

By means of an instruction or primitive (meaning a set of instructions or parameters) from the MAC layer, the PHY layer may prepare an MPDU (MAC PDU) to be transmitted. For example, when a command requesting transmission start of the PHY layer is received from the MAC layer, the PHY layer switches to the transmission mode and configures information (eg, data) provided from the MAC layer in the form of a frame and transmits it. . In addition, when the PHY layer detects a valid preamble of the received frame, it monitors the header of the preamble and sends a command notifying the start of reception of the PHY layer to the MAC layer.

In this way, information transmission/reception in the WLAN system is performed in the form of a frame, and for this purpose, a PHY layer protocol data unit (PPDU) frame format is defined.

A basic PPDU frame may include a Short Training Field (STF), a Long Training Field (LTF), a SIGNAL (SIG) field, and a Data field. The most basic (eg, non-high throughput (HT)) PPDU frame format may consist of only legacy-STF (L-STF), legacy-LTF (L-LTF), SIG field, and data field. In addition, depending on the type of PPDU frame format (eg, HT-mixed format PPDU, HT-greenfield format PPDU, VHT (Very High Throughput) PPDU, etc.), an additional (or different type) STF, LTF, and SIG fields may be included (this will be described later with reference to FIG. 7).

The STF is a signal for signal detection, automatic gain control (AGC), diversity selection, precise time synchronization, and the like, and the LTF is a signal for channel estimation and frequency error estimation. The STF and LTF may be referred to as signals for synchronization and channel estimation of the OFDM physical layer.

The SIG field may include a RATE field and a LENGTH field. The RATE field may include information on modulation and coding rates of data. The LENGTH field may include information about the length of data. Additionally, the SIG field may include a parity bit, a SIG TAIL bit, and the like.

The data field may include a SERVICE field, a physical layer service data unit (PSDU), and a PPDU TAIL bit, and may also include padding bits if necessary. Some bits of the SERVICE field may be used for synchronization of the descrambler at the receiving end. The PSDU corresponds to the MAC PDU defined in the MAC layer, and may include data generated/used in the upper layer. The PPDU TAIL bit can be used to return the encoder to a 0 state. Padding bits may be used to adjust the length of a data field in a predetermined unit.

A MAC PDU is defined according to various MAC frame formats, and a basic MAC frame is composed of a MAC header, a frame body, and a Frame Check Sequence (FCS). The MAC frame may be composed of MAC PDUs and transmitted/received through the PSDU of the data part of the PPDU frame format.

The MAC header includes a frame control field, a duration/ID field, an address field, and the like. The frame control field may include control information required for frame transmission/reception. The duration/ID field may be set to a time for transmitting a corresponding frame or the like. For details of the Sequence Control, QoS Control, and HT Control subfields of the MAC header, refer to the IEEE 802.11 standard document.

A null-data packet (NDP) frame format means a frame format that does not include a data packet. That is, the NDP frame refers to a frame format that includes a physical layer convergence procedure (PLCP) header part (ie, STF, LTF, and SIG fields) in a general PPDU frame format and does not include the remaining parts (ie, data field). do. An NDP frame may also be referred to as a short frame format.

7 is a diagram illustrating examples of PPDUs defined in the IEEE 802.11 standard to which the present disclosure may be applied.

Various types of PPDUs have been used in standards such as IEEE 802.11a/g/n/ac/ax. The basic PPDU format (IEEE 802.11a/g) includes L-LTF, L-STF, L-SIG and Data fields. The basic PPDU format may also be referred to as a non-HT PPDU format.

The HT PPDU format (IEEE 802.11n) additionally includes HT-SIG, HT-STF, and HT-LFT(s) fields to the basic PPDU format. The HT PPDU format shown in FIG. 7 may be referred to as an HT-mixed format. In addition, an HT-greenfield format PPDU may be defined, which does not include L-STF, L-LTF, and L-SIG, but includes HT-GF-STF, HT-LTF1, HT-SIG, one or more HT-LTF, Data Corresponds to a format composed of fields (not shown).

An example of the VHT PPDU format (IEEE 802.11ac) includes VHT SIG-A, VHT-STF, VHT-LTF, and VHT-SIG-B fields in addition to the basic PPDU format.

An example of the HE PPDU format (IEEE 802.11ax) is Repeated L-SIG (RL-SIG), HE-SIG-A, HE-SIG-B, HE-STF, HE-LTF(s), Packet Extension (PE) fields is additionally included in the basic PPDU format. Some fields may be excluded or their length may vary according to detailed examples of the HE PPDU format. For example, the HE-SIG-B field is included in the HE PPDU format for multi-user (MU), and the HE-SIG-B is not included in the HE PPDU format for single user (SU). In addition, the HE trigger-based (TB) PPDU format does not include HE-SIG-B, and the length of the HE-STF field may vary to 8us. The HE ER (Extended Range) SU PPDU format does not include the HE-SIG-B field, and the length of the HE-SIG-A field may vary to 16us.

8 to 10 are diagrams for explaining examples of resource units of a WLAN system to which the present disclosure can be applied.

Referring to FIGS. 8 to 10, a resource unit (RU) defined in a WLAN system will be described. An RU may include a plurality of subcarriers (or tones). The RU may be used when transmitting signals to multiple STAs based on the OFDMA technique. In addition, an RU may be defined even when a signal is transmitted to one STA. RU may be used for STF, LTF, data fields, etc. of the PPDU.

As shown in FIGS. 8 to 10, RUs corresponding to different numbers of tones (ie, subcarriers) are used to select some fields of a 20 MHz, 40 MHz, or 80 MHz X-PPDU (X is HE, EHT, etc.) can be configured. For example, resources may be allocated in RU units shown for the X-STF, X-LTF, and Data fields.

8 is a diagram illustrating an exemplary arrangement of resource units (RUs) used on a 20 MHz band.

As shown at the top of FIG. 8, 26-units (ie, units corresponding to 26 tones) may be allocated. 6 tones may be used as a guard band in the leftmost band of the 20 MHz band, and 5 tones may be used as a guard band in the rightmost band of the 20 MHz band. In addition, 7 DC tones are inserted in the center band, that is, the DC band, and 26-units corresponding to each of the 13 tones may exist on the left and right sides of the DC band. In addition, 26-unit, 52-unit, and 106-unit may be allocated to other bands. Each unit may be allocated for STAs or users.

The RU arrangement of FIG. 8 is utilized not only in a situation for multiple users (MU) but also in a situation for a single user (SU), and in this case, as shown at the bottom of FIG. 8, using one 242-unit it is possible In this case, three DC tones may be inserted.

In the example of FIG. 8 , RUs of various sizes, that is, 26-RU, 52-RU, 106-RU, and 242-RU are exemplified, but the specific size of these RUs may be reduced or expanded. Therefore, in the present disclosure, the specific size of each RU (ie, the number of corresponding tones) is exemplary and not restrictive. In addition, within a predetermined bandwidth (eg, 20, 40, 80, 160, 320 MHz, ...) in the present disclosure, the number of RUs may vary according to the size of the RU. In the examples of FIGS. 9 and/or 10 to be described below, the fact that the size and/or number of RUs can be changed is the same as the example of FIG. 8 .

9 is a diagram illustrating an exemplary arrangement of resource units (RUs) used on a 40 MHz band.

Just as RUs of various sizes are used in the example of FIG. 8 , 26-RU, 52-RU, 106-RU, 242-RU, 484-RU, and the like may also be used in the example of FIG. In addition, 5 DC tones may be inserted at the center frequency, 12 tones are used as a guard band in the leftmost band of the 40MHz band, and 11 tones are used in the rightmost band of the 40MHz band. This can be used as a guard band.

Also, as shown, when used for a single user, a 484-RU may be used.

10 is a diagram illustrating an exemplary arrangement of resource units (RUs) used on an 80 MHz band.

As in the example of FIGS. 8 and 9, RUs of various sizes are used, in the example of FIG. 10, 26-RU, 52-RU, 106-RU, 242-RU, 484-RU, 996-RU, etc. can be used. there is. Also, in the case of an 80 MHz PPDU, RU arrangements of HE PPDUs and EHT PPDUs may be different, and the example of FIG. 10 shows an example of RU arrangements for 80 MHz EHT PPDUs. In the example of FIG. 10, 12 tones are used as the guard band in the leftmost band of the 80 MHz band and 11 tones are used as the guard band in the rightmost band of the 80 MHz band. and EHT PPDU. Unlike the HE PPDU in which 7 DC tones are inserted into the DC band and there is one 26-RU corresponding to each of the 13 tones on the left and right sides of the DC band, in the EHT PPDU, 23 DC tones are inserted into the DC band, There is one 26-RU on the left and right side of the DC band. Unlike the HE PPDU where one null subcarrier exists between 242-RUs rather than the center band, there are five null subcarriers in the EHT PPDU. In the HE PPDU, one 484-RU does not include null subcarriers, but in the EHT PPDU, one 484-RU includes 5 null subcarriers.

Also, as shown, when used for a single user, 996-RU may be used, and in this case, the insertion of 5 DC tones is common to HE PPDU and EHT PPDU.

EHT PPDUs of 160 MHz or higher may be set to a plurality of 80 MHz subblocks in FIG. 10 . The RU arrangement for each 80 MHz subblock may be the same as that of the 80 MHz EHT PPDU of FIG. 10 . If the 80 MHz subblock of the 160 MHz or 320 MHz EHT PPDU is not punctured and the entire 80 MHz subblock is used as part of RU or Multiple RU (MRU), the 80 MHz subblock may use 996-RU of FIG. 10 .

Here, the MRU corresponds to a group of subcarriers (or tones) composed of a plurality of RUs, and the plurality of RUs constituting the MRU may be RUs of the same size or RUs of different sizes. For example, single MRUs are: 52+26-ton, 106+26-ton, 484+242-ton, 996+484-ton, 996+484+242-ton, 2Х996+484-ton, 3Х996-ton, or 3Х996+484-tons. Here, the plurality of RUs constituting one MRU may correspond to small-sized (eg, 26, 52, or 106) RUs or large-sized (eg, 242, 484, or 996) RUs. can That is, one MRU including a small size RU and a large size RU may not be set/defined. Also, a plurality of RUs constituting one MRU may or may not be consecutive in the frequency domain.

If an 80 MHz subblock contains RUs smaller than 996 tones, or parts of the 80 MHz subblock are punctured, the 80 MHz subblock may use RU arrangements other than the 996-tone RU.

The RU of the present disclosure may be used for uplink (UL) and/or downlink (DL) communication. For example, when trigger-based UL-MU communication is performed, an STA (eg, an AP) transmitting a trigger may include trigger information (eg, a trigger frame or a triggered response scheduling (TRS) ), a first RU (eg, 26/52/106/242-RU, etc.) is allocated to the first STA, and a second RU (eg, 26/52/106/242-RU, etc.) is allocated to the second STA. RU, etc.) can be allocated. Thereafter, the first STA may transmit a first trigger-based (TB) PPDU based on the first RU, and the second STA may transmit a second TB PPDU based on the second RU. The first/second TB PPDUs may be transmitted to the AP in the same time interval.

For example, when a DL MU PPDU is configured, an STA (eg, AP) transmitting the DL MU PPDU sends a first RU (eg, 26/52/106/242-RU, etc.) to the first STA. , and a second RU (eg, 26/52/106/242-RU, etc.) may be allocated to the second STA. That is, the transmitting STA (eg, AP) may transmit HE-STF, HE-LTF, and Data fields for the first STA through the first RU within one MU PPDU, and through the second RU HE-STF, HE-LTF, and Data fields for 2 STAs may be transmitted.

Information on the arrangement of RUs may be signaled through HE-SIG-B in HE PPDU format.

11 shows an exemplary structure of a HE-SIG-B field.

As shown, the HE-SIG-B field may include a common field and a user-specific field. If HE-SIG-B compression is applied (eg, full-bandwidth MU-MIMO transmission), the common field may not be included in HE-SIG-B, and HE-SIG-B content A content channel may contain only user-specific fields. If HE-SIG-B compression is not applied, the common field may be included in HE-SIG-B.

The common field may include information on RU allocation (eg, RU assignment, RUs allocated for MU-MIMO, the number of MU-MIMO users (STAs), etc.) .

The common field may include N*8 RU allocation subfields. Here, N is the number of subfields, N = 1 in the case of 20 or 40 MHz MU PPDU, N = 2 in the case of 80 MHz MU PPDU, N = 4 in the case of 160 MHz or 80 + 80 MHz MU PPDU, ... can have a value. One 8-bit RU allocation subfield may indicate the size (26, 52, 106, etc.) and frequency location (or RU index) of RUs included in the 20 MHz band.

For example, if the value of the 8-bit RU allocation subfield is 00000000, nine 26-RUs are sequentially arranged from the leftmost to the rightmost in the example of FIG. If the value is 00000010, five 26-RUs, one 52-RU, and two 26-RUs are arranged in order from leftmost to rightmost. can indicate

As an additional example, if the value of the 8-bit RU allocation subfield is 01000y ₂ y ₁ y ₀ , it indicates that one 106-RU and five 26-RUs are sequentially arranged from the leftmost to the rightmost in the example of FIG. 8 can In this case, multiple users/STAs may be allocated to the 106-RU in the MU-MIMO scheme. Specifically, up to 8 users/STAs can be allocated to the 106-RU, and the number of users/STAs allocated to the 106-RU is determined based on 3-bit information (ie, y ₂ y ₁ y ₀ ). For example, when 3-bit information (y ₂ y ₁ y ₀ ) corresponds to a decimal value N, the number of users/STAs allocated to the 106-RU may be N+1.

Basically, one user/STA may be allocated to each of a plurality of RUs, and different users/STAs may be allocated to different RUs. For RUs larger than a predetermined size (eg, 106, 242, 484, 996-tones, ...), a plurality of users/STAs may be allocated to one RU, and for the plurality of users/STAs, MU -MIMO scheme can be applied.

The set of user-specific fields includes information on how all users (STAs) of the PPDU decode their payloads. User-specific fields may include zero or more user block fields. The non-final user block field includes two user fields (ie, information to be used for decoding in two STAs). The final user block field contains one or two user fields. The number of user fields may be indicated by the RU allocation subfield of HE-SIG-B, the number of symbols of HE-SIG-B, or the MU-MIMO user field of HE-SIG-A there is. User-specific fields may be encoded separately from or independently of common fields.

12 is a diagram for explaining a MU-MIMO method in which a plurality of users/STAs are allocated to one RU.

In the example of FIG. 12, it is assumed that the value of the RU allocation subfield is 01000010. This corresponds to the case where 01000y ₂ y ₁ y ₀ to y ₂ y ₁ y ₀ =010. 010 corresponds to 2 in decimal (ie, N=2) and may indicate that 3 (=N+1) users are allocated to one RU. In this case, one 106-RU and five 26-RUs may be sequentially arranged from the leftmost side to the rightmost side of a specific 20 MHz band/channel. Three users/STAs may be allocated to the 106-RU in a MU-MIMO manner. As a result, a total of 8 users/STAs are allocated to the 20 MHz band/channel, and the user-specific fields of HE-SIG-B may include 8 user fields (ie, 4 user block fields). Eight user fields may be assigned to RUs as shown in FIG. 12 .

User fields can be constructed based on two formats. The user field for MU-MIMO assignments may be in a first format, and the user field for non-MU-MIMO assignments may be in a second format. Referring to the example of FIG. 12 , user fields 1 to 3 may be based on a first format, and user fields 4 to 8 may be based on a second format. The first format and the second format may include bit information of the same length (eg, 21 bits).

The user field of the first format (ie format for MU-MIMO allocation) may be configured as follows. For example, among all 21 bits of one user field, B0-B10 includes identification information (e.g., STA-ID, AID, partial AID, etc.) of the corresponding user, and B11-14 contains information about the corresponding user. It includes spatial configuration information such as the number of spatial streams, B15-B18 includes Modulation and Coding Scheme (MCS) information applied to the Data field of the corresponding PPDU, and B19 is a reserved field. defined, and B20 may include information on a coding type (eg, binary convolutional coding (BCC) or low-density parity check (LDPC)) applied to the Data field of the corresponding PPDU.

The user field of the second format (ie format for non-MU-MIMO assignment) may be configured as follows. For example, among all 21 bits of one user field, B0-B10 includes identification information (e.g., STA-ID, AID, partial AID, etc.) of the user, and B11-13 applies to the corresponding RU. B14 includes information indicating the number of spatial streams to be used (NSTS), B14 includes information indicating whether beamforming is performed (or whether a beamforming steering matrix is applied), and B15-B18 include MCS (Modulation and coding scheme) information, B19 includes information indicating whether dual carrier modulation (DCM) is applied, and B20 includes coding type (eg, BCC or LDPC) information applied to the Data field of the PPDU. can

MCS, MCS information, MCS index, MCS field, etc. used in this disclosure may be indicated by a specific index value. For example, MCS information may be displayed as index 0 to index 11. MCS information includes information on constellation modulation type (eg, BPSK, QPSK, 16-QAM, 64-QAM, 256-QAM, 1024-QAM, etc.), and coding rate (eg, 1/2, 2/ 3, 3/4, 5/6, etc.) Information on a channel coding type (eg, BCC or LDPC) may be excluded from the MCS information.

13 shows an example of a PPDU format to which the present disclosure can be applied.

The PPDU of FIG. 13 may be called various names such as EHT PPDU, transmitted PPDU, received PPDU, first type or Nth type PPDU. For example, the PPDU or EHT PPDU of the present disclosure may be called various names such as a transmission PPDU, a reception PPDU, a first type or an Nth type PPDU. In addition, the EHT PPU may be used in an EHT system and/or a new wireless LAN system in which the EHT system is improved.

The EHT MU PPDU of FIG. 13 corresponds to a PPDU carrying one or more data (or PSDUs) for one or more users. That is, the EHT MU PPDU can be used for both SU transmission and MU transmission. For example, the EHT MU PPDU may correspond to a PPDU for one receiving STA or a plurality of receiving STAs.

In the EHT TB PPDU of FIG. 13, the EHT-SIG is omitted compared to the EHT MU PPDU. Upon receiving a trigger for UL MU transmission (eg, a trigger frame or TRS), the STA may perform UL transmission based on the EHT TB PPDU format.

In the example of the EHT PPDU format of FIG. 13, L-STF to EHT-LTF correspond to a preamble or a physical preamble, and can be generated/transmitted/received/acquired/decoded in the physical layer.

Subcarrier frequency spacing of L-STF, L-LTF, L-SIG, RL-SIG, Universal SIGNAL (U-SIG), EHT-SIG fields (these are referred to as pre-EHT modulated fields) (subcarrier frequency spacing) may be set to 312.5 kHz. The subcarrier frequency interval of the EHT-STF, EHT-LTF, Data, and PE fields (these are referred to as EHT modulated fields) may be set to 78.125 kHz. That is, the tone/subcarrier index of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and EHT-SIG fields is displayed in units of 312.5 kHz, and the EHT-STF, EHT-LTF, Data, The tone/subcarrier index of the PE field may be displayed in units of 78.125 kHz.

The L-LTF and L-STF of FIG. 13 may have the same configuration as the corresponding fields of the PPDU described in FIGS. 6 to 7.

The L-SIG field of FIG. 13 consists of 24 bits and can be used to communicate rate and length information. For example, the L-SIG field includes a 4-bit Rate field, a 1-bit Reserved bit, a 12-bit Length field, a 1-bit Parity field, and a 6-bit tail (Tail) field may be included. For example, the 12-bit Length field may include information about the length or time duration of the PPDU. For example, the value of the 12-bit Length field may be determined based on the type of PPDU. For example, for a non-HT, HT, VHT, or EHT PPDU, the value of the Length field may be determined as a multiple of 3. For example, for the HE PPDU, the value of the Length field may be determined as a multiple of 3 + 1 or a multiple of 3 + 2.

For example, the transmitting STA may apply BCC encoding based on a coding rate of 1/2 to 24-bit information of the L-SIG field. Thereafter, the transmitting STA may obtain 48-bit BCC coded bits. BPSK modulation may be applied to 48-bit coded bits to generate 48 BPSK symbols. The transmitting STA transmits 48 BPSK symbols, pilot subcarriers (eg, {subcarrier index -21, -7, +7, +21}) and DC subcarriers (eg, {subcarrier index 0}) It can be mapped to any location except for . As a result, 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. there is. The transmitting STA may additionally map the signals of {-1, -1, -1, 1} to the subcarrier index {-28, -27, +27, +28}. The above signal may be used for channel estimation in the frequency domain corresponding to {-28, -27, +27, +28}.

The transmitting STA may generate the same RL-SIG as the L-SIG. For RL-SIG, BPSK modulation is applied. The receiving STA may know that the received PPDU is a HE PPDU or an EHT PPDU based on the existence of the RL-SIG.

After the RL-SIG of FIG. 13, a Universal SIG (U-SIG) may be inserted. The U-SIG may be called various names such as a first SIG field, a first SIG, a first type SIG, a control signal, a control signal field, and a first (type) control signal.

The U-SIG may include N bits of information and may include information for identifying the type of EHT PPDU. For example, U-SIG may be configured based on two symbols (eg, two consecutive OFDM symbols). Each symbol (eg, OFDM symbol) for U-SIG may have a duration of 4us, and the U-SIG may have a duration of 8us in total. Each symbol of U-SIG can be used to transmit 26 bits of information. For example, each symbol of U-SIG can be transmitted and received based on 52 data tones and 4 pilot tones.

For example, A bit information (eg, 52 uncoded bits) may be transmitted through the U-SIG (or U-SIG field), and the first symbol of the U-SIG ( For example, U-SIG-1) transmits the first X bit information (eg, 26 un-coded bits) of the total A bit information, and transmits the second symbol of U-SIG (eg, U-SIG -2) may transmit the remaining Y-bit information (eg, 26 un-coded bits) of the total A-bit information. For example, the transmitting STA may obtain 26 un-coded bits included in each U-SIG symbol. The transmitting STA may generate 52-coded bits by performing convolutional encoding (eg, BCC encoding) based on a rate of R = 1/2, and perform interleaving on the 52-coded bits. The transmitting STA may generate 52 BPSK symbols allocated to each U-SIG symbol by performing BPSK modulation on the interleaved 52-coded bits. One U-SIG symbol may be transmitted based on 56 tones (subcarriers) from subcarrier index -28 to subcarrier index +28, except for DC index 0. The 52 BPSK symbols generated by the transmitting STA may be transmitted based on the remaining tones (subcarriers) excluding pilot tones -21, -7, +7, and +21 tones.

For example, the A-bit information (e.g., 52 un-coded bits) transmitted by U-SIG includes a CRC field (e.g., a 4-bit field) and a tail field (e.g., a 6-bit field). ) may be included. The CRC field and the tail field may be transmitted through the second symbol of U-SIG. The CRC field may be generated based on 26 bits allocated to the first symbol of U-SIG and 16 bits remaining except for the CRC/tail field in the second symbol, and may be generated based on a conventional CRC calculation algorithm. can Also, the tail field may be used to terminate the trellis of the convolution decoder, and may be set to 0, for example.

A bit information (eg, 52 un-coded bits) transmitted by U-SIG (or U-SIG field) may be divided into version-independent bits and version-dependent bits. can For example, the size of version-independent bits can be fixed or variable. For example, version-independent bits may be allocated only to the first symbol of the U-SIG, or version-independent bits may be allocated to both the first symbol and the second symbol of the U-SIG. For example, version-independent bits and version-dependent bits may be called various names such as a first control bit and a second control bit.

For example, the version-independent bits of the U-SIG may include a 3-bit physical layer version identifier (PHY version identifier). For example, the 3-bit PHY version identifier may include information related to the PHY version of the transmitted/received PPDU. For example, the first value of the 3-bit PHY version identifier may indicate that the transmission/reception PPDU is an EHT PPDU. In other words, when transmitting the EHT PPDU, the transmitting STA may set the 3-bit PHY version identifier to a first value. In other words, the receiving STA may determine that the received PPDU is an EHT PPDU based on the PHY version identifier having the first value.

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

For example, the version-independent bits of the U-SIG may include information about the length of a transmission opportunity (TXOP) and information about a BSS color ID.

For example, EHT PPDUs are classified into various types (e.g., EHT PPDU related to SU mode, EHT PPDU related to MU mode, EHT PPDU related to TB mode, EHT PPDU related to extended range transmission, etc.) , information on the type of EHT PPDU may be included in version-dependent bits of the U-SIG.

For example, U-SIG includes 1) a bandwidth field including information about bandwidth, 2) a field including information about MCS scheme applied to EHT-SIG, 3) whether DCM scheme is applied to EHT-SIG An indication field containing information related to 4) a field containing information about the number of symbols used for EHT-SIG, 5) a field containing information about whether EHT-SIG is generated over all bands, 6) a field including information about the type of EHT-LTF/STF, and 7) information about a field indicating the length of EHT-LTF and CP length.

Preamble puncturing may be applied to the PPDU of FIG. 13 . Preamble puncturing means applying puncturing to a partial band (eg, a secondary 20 MHz band) among all bands of the PPDU. For example, when an 80 MHz PPDU is transmitted, the STA applies puncturing to the secondary 20 MHz band of the 80 MHz band and transmits the PPDU only through the primary 20 MHz band and the secondary 40 MHz band. there is.

For example, a preamble puncturing pattern may be set in advance. For example, when the first puncturing pattern is applied, puncturing may be applied only to a secondary 20 MHz band within an 80 MHz band. For example, when the second puncturing pattern is applied, puncturing may be applied only to one of two secondary 20 MHz bands included in a secondary 40 MHz band within an 80 MHz band. For example, when the third puncturing pattern is applied, puncturing may be applied only to a secondary 20 MHz band included in a primary 80 MHz band within a 160 MHz band (or 80+80 MHz band). For example, when the fourth puncturing pattern is applied, the primary 40 MHz band included in the primary 80 MHz band within the 160 MHz band (or 80+80 MHz band) is present and does not belong to the primary 40 MHz band. Puncture can be applied to at least one 20 MHz channel that does not

Information on preamble puncturing applied to the PPDU may be included in the U-SIG and/or the EHT-SIG. For example, the first field of the U-SIG includes information about the contiguous bandwidth of the PPDU, and the second field of the U-SIG includes information about preamble puncturing applied to the PPDU. there is.

For example, U-SIG and EHT-SIG may include information about preamble puncturing based on the following method. If the bandwidth of the PPDU exceeds 80 MHz, the U-SIG may be individually configured in units of 80 MHz. For example, if the bandwidth of the PPDU is 160 MHz, the PPDU may include a first U-SIG for a first 80 MHz band and a second U-SIG for a second 80 MHz band. In this case, the first field of the first U-SIG includes information about the 160 MHz bandwidth, and the second field of the first U-SIG includes information about preamble puncturing applied to the first 80 MHz band (ie, preamble information on a puncturing pattern). In addition, the first field of the second U-SIG includes information about the 160 MHz bandwidth, and the second field of the second U-SIG includes information about preamble puncturing applied to the second 80 MHz band (ie, preamble fung information about the processing pattern). The EHT-SIG following the first U-SIG may include information on preamble puncturing applied to the second 80 MHz band (ie, information on the preamble puncturing pattern), and The EHT-SIG may include information on preamble puncturing applied to the first 80 MHz band (ie, information on a preamble puncturing pattern).

Additionally or alternatively, the U-SIG and EHT-SIG may include information about preamble puncturing based on the method below. The U-SIG may include information on preamble puncturing for all bands (ie, information on a preamble puncturing pattern). That is, EHT-SIG does not include information on preamble puncturing, and only U-SIG may include information on preamble puncturing (ie, information on preamble puncturing patterns).

U-SIG may be configured in units of 20 MHz. For example, if an 80 MHz PPDU is configured, the U-SIG may be duplicated. That is, the same 4 U-SIGs may be included in the 80 MHz PPDU. PPDUs exceeding 80 MHz bandwidth may include different U-SIGs.

The EHT-SIG of FIG. 13 may include control information for the receiving STA. EHT-SIG may be transmitted through at least one symbol, and one symbol may have a length of 4us. Information on the number of symbols used for EHT-SIG may be included in U-SIG.

EHT-SIG may include technical features of HE-SIG-B described with reference to FIGS. 11 and 12 . For example, EHT-SIG, like the example of FIG. 8, may include a common field and a user-specific field. Common fields of EHT-SIG may be omitted, and the number of user-specific fields may be determined based on the number of users.

As in the example of FIG. 11, the common field of EHT-SIG and the user-specific field of EHT-SIG may be individually coded. One user block field included in the user-specific field contains information for two user fields, but the last user block field included in the user-specific field contains information for one or two user fields. May contain fields. That is, one user block field of the EHT-SIG may include up to two user fields. As in the example of FIG. 12, each user field may be related to MU-MIMO allocation or non-MU-MIMO allocation.

As in the example of FIG. 11, the common field of EHT-SIG may include a CRC bit and a Tail bit, the length of the CRC bit may be determined as 4 bits, and the length of the Tail bit may be determined as 6 bits and set to 000000. can

As in the example of FIG. 11, the common field of EHT-SIG may include RU allocation information. RU allocation information may mean information about the location of an RU to which a plurality of users (ie, a plurality of receiving STAs) are allocated. RU allocation information may be configured in units of 8 bits (or N bits).

A mode in which the common field of EHT-SIG is omitted may be supported. A mode in which the common field of the EHT-SIG is omitted may be called a compressed mode. When the compressed mode is used, a plurality of users (ie, a plurality of receiving STAs) of the EHT PPDU may decode the PPDU (eg, the data field of the PPDU) based on non-OFDMA. That is, a plurality of users of the EHT PPDU can decode a PPDU (eg, a data field of the PPDU) received through the same frequency band. When a non-compressed mode is used, multiple users of the EHT PPDU can decode the PPDU (eg, the data field of the PPDU) based on OFDMA. That is, a plurality of users of the EHT PPDU may receive the PPDU (eg, the data field of the PPDU) through different frequency bands.

EHT-SIG can be configured based on various MCS techniques. As described above, information related to the MCS scheme applied to the EHT-SIG may be included in the U-SIG. EHT-SIG may be configured based on the DCM technique. For example, among N data tones (eg, 52 data tones) allocated for EHT-SIG, the first modulation scheme is applied to half of the continuous tones, and the second modulation scheme is applied to the remaining half of the tones. techniques can be applied. That is, the transmitting STA modulates specific control information into a first symbol based on a first modulation scheme and allocates to consecutive half tones, modulates the same control information into a second symbol based on a second modulation scheme, and modulates the remaining consecutive can be assigned to half a ton. As described above, information related to whether the DCM technique is applied to the EHT-SIG (eg, a 1-bit field) may be included in the U-SIG. The EHT-STF of FIG. 13 can be used to improve automatic gain control (AGC) estimation in a MIMO environment or an OFDMA environment. The EHT-LTF of FIG. 13 may be used to estimate a channel in a MIMO environment or an OFDMA environment.

Information about the type of STF and/or LTF (including information about a guard interval (GI) applied to LTF) may be included in the U-SIG field and/or the EHT-SIG field of FIG. 13 .

The PPDU (ie, EHT PPDU) of FIG. 13 may be configured based on examples of RU arrangements of FIGS. 8 to 10 .

For example, an EHT PPDU transmitted on a 20 MHz band, that is, a 20 MHz EHT PPDU may be configured based on the RU of FIG. 8 . That is, the location of the EHT-STF, EHT-LTF, and RU of the data field included in the EHT PPDU may be determined as shown in FIG. 8 . An EHT PPDU transmitted on a 40 MHz band, that is, a 40 MHz EHT PPDU may be configured based on the RU of FIG. 9 . That is, the location of the EHT-STF, EHT-LTF, and RU of the data field included in the EHT PPDU may be determined as shown in FIG. 9 .

The EHT PPDU transmitted on the 80 MHz band, that is, the 80 MHz EHT PPDU may be configured based on the RU of FIG. 10 . That is, the location of the EHT-STF, EHT-LTF, and RU of the data field included in the EHT PPDU may be determined as shown in FIG. 10 . The tone-plan for 80 MHz in FIG. 10 may correspond to two repetitions of the tone-plan for 40 MHz in FIG.

The tone-plan for 160/240/320 MHz may be configured in the form of repeating the pattern of FIG. 9 or 10 several times.

The PPDU of FIG. 13 can be identified as an EHT PPDU based on the following method.

The receiving STA may determine the type of the received PPDU as the EHT PPDU based on the following items. For example, 1) the first symbol after the L-LTF signal of the received PPDU is BPSK, 2) RL-SIG in which the L-SIG of the received PPDU is repeated is detected, and 3) the L-LTF signal of the received PPDU is detected. When a result of applying a modulo 3 operation to the value of the Length field of the SIG (ie, a remainder after dividing by 3) is detected as 0, the received PPDU may be determined as an EHT PPDU. When the received PPDU is determined to be an EHT PPDU, the receiving STA may determine the type of the EHT PPDU based on bit information included in symbols subsequent to the RL-SIG of FIG. 13 . In other words, the receiving STA is 1) the first symbol after the L-LTF signal that is BSPK, 2) the RL-SIG that is consecutive to the L-SIG field and the same as the L-SIG, and 3) the result of applying modulo 3 is 0 Based on the L-SIG including the set Length field, the received PPDU may be determined as an EHT PPDU.

For example, the receiving STA may determine the type of the received PPDU as the HE PPDU based on the following. For example, 1) the first symbol after the L-LTF signal is BPSK, 2) RL-SIG in which L-SIG is repeated is detected, and 3) the result of applying modulo 3 to the length value of L-SIG is If 1 or 2 is detected, the received PPDU may be determined as a HE PPDU.

For example, the receiving STA may determine the type of the received PPDU as non-HT, HT, and VHT PPDU based on the following items. For example, if 1) the first symbol after the L-LTF signal is BPSK and 2) RL-SIG in which L-SIG is repeated is not detected, the received PPDU is determined to be non-HT, HT, and VHT PPDU. can In addition, even if the receiving STA detects repetition of the RL-SIG, if the result of applying modulo 3 to the Length value of the L-SIG is detected as 0, the received PPDU can be determined as non-HT, HT, and VHT PPDUs there is.

The PPDU of FIG. 13 can be used to transmit and receive various types of frames. For example, the PPDU of FIG. 13 may be used for (simultaneous) transmission and reception of one or more of a control frame, a management frame, or a data frame.

sounding protocol sequence

The HE non-trigger based (non-TB) sounding sequence is an HE beamformer having an individually addressed HE NDP announcement frame including one STA information field, as shown in (a) of FIG. ), and after SIFS, the HE sounding NDP may be transmitted to the (single) HE beamformee. The HE beamformer may respond by receiving the HE sounding NDP from the HE beamformer and transmitting the HE compressed beamforming/CQI frame to the HE beamformer after SIFS.

If the STA identified by the RA (receiver address) field is a mesh STA, AP, or IBSS STA, the AID11 subfield of the STA information field is set to 0 or the AID of the STA identified by the RA field of the HE NDP announcement frame. can be set.

Specifically, the HE beamformer starting the HE non-TB sounding sequence must transmit a HE NDP announcement frame with a single STA information (Info) field, and the STA identified by the RA field is a mesh STA, AP or IBSS member In the case of an STA, the AID11 field value of the corresponding STA information field may be set to 0 or the AID of the STA identified by the RA field other than 2047. The HE beamformer may start a HE non-TB sounding sequence with the HE beamformer to request SU feedback over the entire bandwidth. The HE beamformer may not start HE non-TB with a HE NDP announcement frame having a partial BW information subfield indicating less than the entire bandwidth.

As shown in (b) of FIG. 14, the HE TB sounding sequence uses a broadcast HE NDP announcement frame having two or more STA information fields, and uses HE beamformer, SIFS, HE sounding NDP, and SIFS Afterwards, it can be initiated by a BFRP trigger frame. One or more HE beamformers may receive the BFPR trigger frame and respond with a HE compressed beamforming/CQI frame after SIFS. Here, the BFRQ trigger frame may include one or more user info fields for identifying HE beamformes.

The HE beamformer that starts the HE TB sounding sequence may transmit a HE NDP announcement frame including two or more STA information fields and an RA field set to a broadcast address. The HE beamformer may initiate a HE TB sounding sequence to request MU feedback over the entire bandwidth.

The HE beamformer may initiate the HE TB sounding sequence to request the feedback variant only if the feedback variant is calculated based on the parameters supported by the HE beamformer; otherwise, the HE beamformer may not request a feedback variant calculated based on a parameter not supported by the HE beamformie.

A HE beamformer that transmits a HE NDP announcement frame to a HE beamformer that is an AP, TDLS peer STA, mesh STA, or IBSS STA includes one STA information (info) field on the HE NDP announcement frame And the AID11 field may be set to 0 in the STA information field of the frame.

An HE beamformer that is an AP and transmits the HE NDP announcement frame to one or more HE beamformers may set the AID11 field of the STA information field for identifying the non-AP STA to 11 LSB of the AID of the non-AP STA. The HE NDP announcement frame may not include several STA information fields having the same value in the AID11 subfield.

The HE beamformer transmitting the HE NDP announcement frame starting the HE TB sounding sequence has an AID11 subfield value of 2047 to indicate a disallowed subchannel during punctured channel operation STA information field can include When the STA information field is present, the STA information field having an AID11 value of 2047 may be the first STA information field of the frame. The HE beamformer transmitting the HE NDP announcement frame may not include one or more STA information fields having an AID11 subfield value of 2047.

As shown in (b) of FIG. 14, the HE beamformer that starts the HE TB sounding sequence may transmit another BFRP trigger frame in the same TXOP. From the HE beamformer, the HE beamformer may request a HE compressed beamforming/CQI report that has not been processed in a previous BFRP trigger frame or request retransmission of a HE compressed beamforming/CQI report using an additional BFRP trigger frame. . The HE beamformer may not transmit a BFRP trigger frame identifying the STA identified in the HE NDP announcement frame of the HE TB sounding sequence unless it is in the same TXOP as the HE TB sounding sequence.

In the HE TB sounding sequence, the STA information field of the HE NDP announcement frame requesting SU or MU feedback is used by the HE beamformer identified by the STA information field for generating SU or MU feedback Subcarrier grouping to be used (Ng), codebook size and number of columns (Nc). And, in the HE TB sounding sequence, the STA information field of the HE NDP announcement frame requesting CQI feedback may indicate Nc to be used by the HE beamforme identified by the STA information field for generating CQI feedback.

Polling phase of trigger-based ranging

15 is a diagram for explaining examples of available windows in a trigger-based ranging exchange process to which the present disclosure can be applied.

Trigger-based (TB) ranging corresponds to a dynamic trigger-based variant of the fine timing measurement (FTM) process. Here, the polling phase corresponds to the first phase in each of the polling/sounding/reporting triplet.

Each polling phase instance may include one or more polling ranging trigger frames (or ranging trigger frames in which the subvariant is polling), and receive up to one response from the initiator STA (ISTA) for this there is. The poll ranging trigger frame may be referred to as a TF ranging poll frame. A responder STA (RSTA) may allocate each RU in a TF ranging poll frame for one ISTA. The ISTA addressed by the user information field in the TF ranging poll frame may request to participate in the measurement in the corresponding availability window, and for this purpose, in the RU allocation identified in the TF ranging poll frame, HE It can respond with CTS-to-self in a single-MPDU (S-MPDU) in the TB PPDU. For example, FIG. 15(a) shows a TB ranging availability window having two instances of polling/sounding/reporting triplets in separate TXOPs.

If the available bandwidth does not allow polling using a single TH ranging poll frame of all ISTAs assigned to that available window, the RSTA schedules one or more extra polling/sounding/reporting triplets within that available window you can try RSTA sets the value of the more TF (more TF) subfield of the common information field to 1 and sets the RA field to the broadcast address in the TF ranging poll frame and the TF (trigger frame) in subsequent polling, By setting, Additional polling/sounding/reporting triplets may be indicated. If there is no additional polling / sounding / reporting triplet in the same available window, the RSTA is a common information field in the TF ranging poll frame and TF in the subsequent measurement sounding and measurement reporting phases of the same available window The value of the more TF subfield of may be set to 0 and the RA field may be set to a broadcast address. Upon receiving this frame, ISTAs not addressed by the user information field of the TF may enter a doze state if there are no other conditions to remain awake. Based on the maximum allowed TXOP duration and the expected length for additional instances of the polling/sounding/reporting triplet, the additional polling/sounding/reporting triplet may be transmitted in the same TXOP (e.g., FIG. 15(b) ) indicates a TB ranging availability window with two instances of polling/sounding/reporting triplets within a single TXOP); Or it may be transmitted in a new TXOP (eg, see FIG. 15 (a)).

trigger frame structure

16 is a diagram illustrating an exemplary format of a trigger frame to which the present disclosure may be applied.

The trigger frame may allocate resources for one or more TB PPDU transmissions and request TB PPDU transmission. The trigger frame may also include other information required by the STA transmitting the TB PPDU in response. A trigger frame may include common info and user info list fields in a frame body.

The common information field is information commonly applied to transmission of one or more TB PPDUs requested by the trigger frame, for example, trigger type, UL length, presence or absence of a subsequent trigger frame (eg, More TF), CS (channel) sensing) request, UL BW (bandwidth), and the like. 16 shows an EHT variant common information field format by way of example.

The 4-bit trigger type subfield may have a value of 0-15. Among them, values 0, 1, 2, 3, 4, 5, 6, 7, and 8 of the trigger type subfield are basic, beamforming report poll (BFRP), and multi user-block acknowledgment request (MU-BAR), respectively. ), MU-RTS (multi user-request to send), BSRP (Buffer Status Report Poll), GCR (groupcast with retries) MU-BAR, BQRP (Bandwidth Query Report Poll), NFRP (NDP Feedback Report Poll) and Ranging It is defined as corresponding, and values of 9-15 are defined as reserved.

Among common information, a trigger dependent common info subfield may include information selectively included based on a trigger type.

A special user info field may be included in the trigger frame. The special user information field does not include user specific information and includes extended common information not provided in the common information field.

The user information list includes zero or more user info fields. 16 illustrates an EHT variant user information field format.

The AID12 subfield basically represents a user information field for an STA having a corresponding AID. In addition, when the AID12 field has a predetermined specific value, it may be used for other purposes, such as allocating a random access (RA)-RU or being configured in the form of a special user info field. The special user information field is a user information field that does not include user specific information but includes extended common information not provided in the common information field. For example, the special user information field may be identified by the AID12 value of 2007, and the special user information field flag subfield in the common information field may indicate whether the special user information field is included.

The RU allocation subfield may indicate the size and location of RU/MRU. To this end, the RU allocation subfield may be interpreted together with the PS160 (primary/secondary 160 MHz) subfield of the user information field and the UL BW subfield of the common information field.

For example, a trigger dependent user info subfield may not exist in a sounding subvariant of a ranging trigger frame.

In addition, the user information field for the sounding subvariant may include an AID12/RSID12 subfield, an I2R Rep subfield, an SS Allocation subfield, and a UL target RSSI subfield.

Here, the AID12/RSID12 subfield may be the same as the corresponding subfield in the ranging trigger frame of the subvariant poll. The I2R Rep subfield may signal the repetition number (N_REP) of HE LTF symbols in the corresponding HE TB Raing NDP from the STA indicated in the AID12/RSID12 subfield. The value of the I2R Rep subfield is the same as all user information fields of the trigger frame. The SS allocation subfield and the UL target RSSI subfield may be the same as the corresponding subfields in the basic trigger frame.

WLAN sensing procedure

A WLAN sensing procedure (hereinafter referred to as a sensing procedure) refers to a procedure for obtaining recognition information about a surrounding environment based on information about a channel environment (or state) included in a signal transmitted from a transmitter to a receiver. Each STA may provide additional services that can be applied to real life in various forms based on information about the surrounding environment acquired through a sensing procedure.

Here, the information on the surrounding environment, for example, gesture recognition information, fall detection information, intrusion detection information, user motion detection, health monitoring information information), or pet movement detection.

A sensing procedure may be initiated by a sensing initiator. A sensing initiator refers to an STA that instructs one or more STAs having a sensing function (or capability) to initiate a sensing session using a (WLAN) signal.

For example, the sensing initiator may transmit a signal for sensing (eg, a PPDU for sensing measurement) to one or more STAs having a sensing function, or may transmit a frame requesting transmission of a signal for sensing.

A sensing session means a time period (or instance) in which a series of sensing procedures are performed. That is, a sensing session refers to a time interval (or instance) in which various protocols related to transmission and reception of signals for sensing are exchanged or an instance of a sensing procedure having associated operational parameters of the corresponding instance. Sensing sessions may be allocated to STAs periodically or aperiodically as needed.

A sensing session includes (sensing) setup phase, (sensing) measurement setup phase, (sensing measurement instance phase), reporting phase, and termination. It can consist of steps, etc. The negotiation step (or process) for determining the operating parameters may be configured as a sub-step of the setup step (ie, a part of the setup step) or may be configured independently of the setup step.

Also, the sensing session may include a plurality of sub-session, and each sub-session may include a measurement step and a reporting step. Here, the sub-session may be expressed as a sensing burst, a measurement instance, or a measurement burst.

A sensing responder refers to an STA participating in a sensing session initiated by a sensing initiator. The sensing responder may transmit a result obtained by performing the sensing operation (eg, channel state information, etc.) to the sensing initiator, or may transmit a signal for sensing to the sensing initiator according to an instruction of the sensing initiator.

A sensing transmitter refers to an STA that transmits a signal for sensing (eg, a PPDU for sensing measurement, etc.) during a sensing session (or burst). A sensing receiver refers to an STA that receives a signal for sensing during a sensing session (or burst).

When a sensing session consists of a plurality of sensing bursts, sensing senders/receivers in all sensing bursts may be the same, but are not limited thereto. Sensing senders/receivers in some sensing bursts may be different, and sensing senders/receivers may be different for each sensing burst.

Within a sensing session, the sensing initiator may operate as a sensing transmitter or sensing receiver, and the sensing responder may operate as a sensing receiver or sensing transmitter.

And, during each sensing burst constituting the sensing session, signal transmission for sensing by the sensing sender and feedback transmission by the sensing receiver may be performed. As another example, during each sensing burst, only signal transmission for sensing by a sensing sender may be performed.

Each sensing burst may be defined continuously in time, but is not limited thereto, and may be defined discontinuously in time. When each sensing burst is defined discontinuously in time, the sensing burst may be defined identically or similarly to a transmission opportunity (TXOP). Here, TXOP means a time interval in which a specific STA may have the right to start a frame exchange sequence on a wireless medium (WM).

Methods related to wireless LAN sensing measurement

In the WLAN system, trigger frame based (TB) measurement for channel measurement may be applied in relation to sensing measurement.

In relation to the above-described TB measurement, a TB sensing measurement instance may be used. Here, the TB sensing measurement instance may consist of a polling phase, a trigger frame (TF) sounding phase, and/or a null data packet announcement (NDPA) sounding phase.

17 is a diagram illustrating a configuration example of a TB sensing measurement instance to which the present disclosure may be applied.

17(a) shows a TB sensing measurement instance composed of [polling phase, TF sounding phase], and FIG. 17(b) shows a TB sensing measurement instance composed of [polling phase, TF sounding phase, NDPA sounding phase] 17(c) shows a TB sensing measurement instance composed of [polling phase, NDPA sounding phase], and FIG. 17(d) shows TB composed of [polling phase, NDPA sounding phase, TF sounding phase] Represents a sensing measurement instance.

Referring to FIG. 17 , the polling phase may be set/defined to be performed prior to the sounding phase (ie, the TF sounding phase and/or the NDPA sounding phase) in all configurations of the TB sensing measurement instance. In the corresponding polling phase, a trigger frame for identifying STA(s) participating in sensing measurement may be transmitted.

In the present disclosure, it is described that an STA transmitting a trigger frame or NDPA is mainly an AP, but it goes without saying that a trigger frame or NDPA may also be transmitted by a non-AP STA.

In relation to the above-described TB sensing measurement instance, the TF sounding phase and the NDPA sounding phase may be configured as shown in FIGS. 18 and 19, respectively.

18 is a diagram illustrating an example of a TF sounding phase to which the present disclosure may be applied.

Referring to FIG. 18, in the TF sounding phase, a sensing initiator (eg, a first STA) sends a trigger frame to one or more sensing responder(s) (eg, a second STA(s)). can transmit The sensing responder(s) may transmit NDP after SIFS based on trigger frame reception. For example, trigger frame transmission for requesting / soliciting NDP transmission (s) from STA (s) may be performed by the AP, and NDP transmission by STA (s) is based on the reception of the trigger frame can be performed after SIFS.

At this time, as shown in FIG. 18(a), the sensing initiator may request/solicit NDP frame transmission from one or more sensing responder(s) participating in sensing measurement. The NDP frame may be transmitted through an OFDMA transmission scheme or an MU-MIMO transmission scheme.

Alternatively, as shown in FIG. 18(b), the sensing responder(s) receiving the trigger frame and participating in sensing may sequentially transmit NDP. In this case, each STA may receive/obtain information on the order of NDP transmission through the trigger frame. In addition, the corresponding NDP frame(s) may be transmitted in a bandwidth (BW) indicated through a trigger frame.

19 is a diagram illustrating an example of an NDPA sounding phase to which the present disclosure may be applied.

Referring to FIG. 19, in the NDPA sounding phase, a sensing initiator may transmit a sensing NDPA frame, and may transmit an NDP to one or more sensing responder(s) after SIFS based on the transmission of the sensing NDPA frame. NDPA sounding can be used by pre-HE STA(s), that is, its use is not limited to HE STA(s) and/or EHT STA(s). For example, transmission of a sensing NDPA frame may be performed by an AP, and NDP transmission may be performed by a corresponding AP after SIFS based on transmission of the sensing NDPA frame.

Hereinafter, in the case of using the above-described TB sensing measurement instance, the present disclosure proposes a method of instructing other STAs (eg, responders) with information on how TB sensing measurement is configured through a trigger frame. That is, a method of instructing/transmitting information related to the configuration of a TB sensing measurement instance is proposed.

20 is a diagram illustrating an example of a method of performing a sounding phase by a first STA according to the present disclosure.

Referring to FIG. 20 , in step S2010, the first STA may transmit information related to the order of one or more sounding phases in a trigger based (TB) sensing measurement instance to one or more second STAs. Here, the one or more sounding phases may include at least one of a trigger frame (TF) sounding phase and a null data packet announcement (NDPA) sounding phase.

At this time, information related to the order may be transmitted through a trigger frame within the TB sensing measurement instance. For example, the trigger frame may be a trigger frame transmitted and received in a polling phase within the TB sensing measurement instance.

In addition, for example, the information related to the order includes a first measurement instance type composed of only the TF sounding phase, a second measurement instance type composed of the TF sounding phase and the NDPA sounding phase in order, the NDPA sounding phase and the TF sounding One of the third measurement instance type configured in phase order or the fourth measurement instance type configured only with NDPA sounding phases may be indicated. Alternatively, the information related to the order is a first measurement instance type composed of only TF sounding phases, a second measurement instance type composed of TF sounding phases and NDPA sounding phases in order, or NDPA sounding phases and TF sounding phases in order One of the configured third measurement instance types may be indicated. Alternatively, the information related to the order may include information indicating whether an NDPA sounding phase following the TF sounding phase exists.

Also, for example, information related to the order may be included in trigger dependent common information of the trigger frame.

In this regard, the trigger frame may include information indicating a first sensing trigger subtype related to the polling phase or a second sensing trigger subtype related to the sounding phase. Additionally or alternatively, the trigger frame may include identification information about sensing measurement setup related to one or more TB sensing measurement instances including the TB sensing measurement instance. Additionally or alternatively, the trigger frame may include identification information about the TB sensing measurement instance.

Regarding the identification information for the TB sensing measurement instance, if there is an NDPA sounding phase following the TF sounding phase in the TB sensing measurement instance, the sounding dialog token number related to the NDPA sounding phase (sounding dialog token number) may be set to the same value as the identification information for the TB sensing measurement instance. Conversely, if there is a TF sounding phase following the NDPA sounding phase in the TB sensing measurement instance, the value of the identification information for the TB sensing measurement instance is a sounding dialog token number related to the NDPA sounding phase and can be set to the same value.

Also, for example, the first STA may be a sensing initiator, and the second STA may be a sensing responder.

Also, for example, the trigger frame may include bit information for distinguishing a ranging trigger type from a sensing trigger type.

Thereafter, in step S2020, the first STA may perform the one or more sounding phases based on information related to the order in step S2010 within the TB sensing measurement instance.

21 is a diagram illustrating an example of a method of performing a sounding phase by a second STA according to the present disclosure.

Referring to FIG. 21 , in step S2110, the second STA may receive information related to a sequence of one or more sounding phases in a trigger based (TB) sensing measurement instance from the first STA. Here, the one or more sounding phases may include at least one of a trigger frame (TF) sounding phase and a null data packet announcement (NDPA) sounding phase.

At this time, information related to the order may be transmitted through a trigger frame within the TB sensing measurement instance. For example, the trigger frame may be a trigger frame transmitted and received in a polling phase within the TB sensing measurement instance.

In addition, for example, the information related to the order includes a first measurement instance type composed of only the TF sounding phase, a second measurement instance type composed of the TF sounding phase and the NDPA sounding phase in order, the NDPA sounding phase and the TF sounding One of the third measurement instance type configured in phase order or the fourth measurement instance type configured only with NDPA sounding phases may be indicated. Alternatively, the information related to the order is a first measurement instance type composed of only TF sounding phases, a second measurement instance type composed of TF sounding phases and NDPA sounding phases in order, or NDPA sounding phases and TF sounding phases in order One of the configured third measurement instance types may be indicated. Alternatively, the information related to the order may include information indicating whether an NDPA sounding phase following the TF sounding phase exists.

Also, for example, information related to the order may be included in trigger dependent common information of the trigger frame.

In this regard, the trigger frame may include information indicating a first sensing trigger subtype related to the polling phase or a second sensing trigger subtype related to the sounding phase. Additionally or alternatively, the trigger frame may include identification information about sensing measurement setup related to one or more TB sensing measurement instances including the TB sensing measurement instance. Additionally or alternatively, the trigger frame may include identification information about the TB sensing measurement instance.

Regarding the identification information for the TB sensing measurement instance, if there is an NDPA sounding phase following the TF sounding phase in the TB sensing measurement instance, the sounding dialog token number related to the NDPA sounding phase (sounding dialog token number) may be set to the same value as the identification information for the TB sensing measurement instance. Conversely, if there is a TF sounding phase following the NDPA sounding phase in the TB sensing measurement instance, the value of the identification information for the TB sensing measurement instance is a sounding dialog token number related to the NDPA sounding phase and can be set to the same value.

Also, for example, the first STA may be a sensing initiator, and the second STA may be a sensing responder.

Also, for example, the trigger frame may include bit information for distinguishing a ranging trigger type from a sensing trigger type.

Thereafter, in step S2120, the second STA may perform the one or more sounding phases based on information related to the order in step S2010 within the TB sensing measurement instance.

Hereinafter, in relation to the operations described in FIGS. 20 and 21 described above, specific methods for instructing/transmitting information related to the configuration of a TB sensing measurement instance and the like will be described.

As in the above-described examples of TB sensing measurement instances in FIG. 17, when a TF sounding phase exists (eg, FIG. 17 (a), FIG. 17 (b), and FIG. 17 (d)), the first STA is channel For measurement, a trigger frame requesting/soliciting NDP transmission may be transmitted to one or more second STAs. In addition, even in the polling phase included in the examples of TB sensing measurement instances in FIG. 17, the first STA may transmit a trigger frame for polling purposes to one or more second STAs regarding participation in sensing measurement.

Here, the first STA may be an STA corresponding to a sensing initiator/transmitter, and the second STA may be an STA corresponding to a sensing responder/receiver. In addition, the opposite case is also possible, and transmission and reception of trigger frames between STAs may be performed regardless of classification of an initiator and/or a responder.

At this time, the second STA(s) participating in the sensing may identify/acquire information on NDP transmission through the received trigger frame.

In order to indicate a trigger frame (hereinafter, a sensing trigger frame) used in the above-described sensing process, information/field indicating that the trigger frame is for sensing may be included in the corresponding trigger frame.

For example, in order to indicate a sensing trigger frame, it may be indicated that the trigger frame is used for sensing by using one of reserved values among the reserved trigger type subfield values.

As a specific example, one of the reserved values '9' to '15' of the trigger type subfield may be used, and '9' may be allocated to indicate a sensing trigger frame as shown in Table 1 below.

Trigger type subfield value	trigger frame variant
...	...
8	Ranging
9	Sensing
10-15	Reserved

As another example, a trigger type subfield value previously used/prescribed is used (eg, '8' indicating ranging), but the sensing trigger frame is indicated through additional information/field indicating that the trigger frame is for sensing. may be

As described above in the present disclosure, a sensing trigger frame in a TB sensing measurement instance may be used for various sensing operations. A corresponding sensing operation type may be defined as a subvariant of a sensing trigger frame.

For example, the subvariant of the sensing trigger frame may include at least one of the following subvariants.

-Poll subvariant: A subvariant for a trigger frame transmitted to identify an STA (e.g., responder) participating in sensing

- Sounding subvariant: Subvariant for a trigger frame transmitted to request / solicit NDP transmission to perform sensing measurement

-Secure sounding subvariant: A trigger transmitted to perform sensing measurement using a secure sequence determined between the first STA (eg, initiator) and the second STA (eg, responder) Subvariant to frame

- Report subvariant: A subvariant for a trigger frame used to report a result of performing channel measurement

In relation to the subvariants described above, an indication of a specific subvariant may be performed through a preset/defined subfield of a sensing trigger frame.

For example, an indication of a specific subvariant among the subvariants described above may be performed through a trigger dependent common information (Trigger Dependent Common Info) subfield of a sensing trigger frame. The name of the corresponding subfield is an example, and it is of course possible to change and use another subfield name.

As shown in Table 2 below, the sensing trigger frame subvariant may be indicated through a 4-bit sensing trigger subtype subfield.

Sensing Trigger Subtype Subfield Value	Sensing trigger frame subvariant
0	pole
One	sounding
2	security sounding
3	report
4-15	Reserved

Also, unlike Table 2, the sensing trigger subtype may be composed of subfields with a different number of bits (eg, 3 bits).

Regarding the method of constructing the trigger frame, in the present disclosure, a case in which the sensing trigger frame is used as a sounding subvariant is mainly described, but the method may also be applied to other subvariants. For example, the trigger frame proposed in the present disclosure may correspond to a polling phase, that is, a trigger frame for a poll subvariant.

In addition, as described above in the present disclosure, a TB sensing measurement instance may be variously configured using a TF sounding phase and/or an NDPA sounding phase. That is, various types of TB sensing measurement instances may exist in consideration of the existence and/or order of the TF sounding phase and the NDPA sounding phase.

Accordingly, the configuration information for the TB sensing measurement instance or the configuration information for the sounding phase may be performed through a specific preset/defined subfield of the sensing trigger frame.

For example, the configuration information for the above-described TB sensing measurement instance or configuration information for the sounding phase may be delivered through a trigger dependent common information subfield of the sensing trigger frame. That is, the first STA (eg, sensing initiator) may transmit the configuration information to the second STA (eg, sensing responder) through a corresponding subfield.

Hereinafter, for convenience of explanation, the corresponding subfield is referred to as a sounding order/measurement configuration subfield. The name of the corresponding subfield is an example, and it is of course possible to change and use another subfield name.

As an example, the sounding order/measurement configuration subfield is all configurations/cases in the above-described FIG. 17 (ie, FIGS. 17(a), 17(b), 17(c) and 17(d)) It can be set / defined to indicate in consideration of.

That is, the configuration information for the TB sensing measurement instance or the configuration information for the sounding phase may be indicated through the trigger dependent common information subfield of the sensing trigger frame. As shown in Table 3 below, the corresponding subfield may be composed of a 2-bit table.

value (bits)	contents
0 (00)	TF sounding
1 (01)	TF sounding + NDPA sounding
2 (10)	NDPA sounding + TF sounding
3 (11)	NDPA sounding

The subfield size in Table 3 is an example, and may consist of 2 bits or more. Also, Table 3 above is an example, and indication bits/values for each sounding phase configuration may be set differently.

As another example, the sounding order/measurement configuration subfield is all configurations/cases in FIG. 17 described above (ie, FIGS. 17(a), 17(b), 17(c) and 17(d)) It may be set / defined to indicate only in consideration of the configuration / case in which TF sounding is used / included.

Since the corresponding information is transmitted through the trigger frame, the corresponding information may be transmitted through the NDPA for a configuration/case in which only NDPA sounding is used (eg, FIG. 17(c)). Therefore, in this case, the corresponding information does not need to be transmitted through the trigger frame.

Therefore, in this case, in order to reduce unnecessary indications, the corresponding subfield may be configured as shown in Table 4 below (eg, a 2-bit table).

value (bits)	contents
0 (00)	TF sounding
1 (01)	TF sounding + NDPA sounding
2 (10)	NDPA sounding + TF sounding
3 (11)	Reserved

The subfield size in Table 4 is an example, and may consist of 2 bits or more. Also, Table 4 above is an example, and indication bits/values for each sounding phase configuration may be set differently.

As another example, information on whether NDPA sounding is performed after TF sounding may be indicated through the sounding order/measurement configuration subfield.

Regarding the sounding phase, in the TB sensing measurement instance, the trigger frame can be used only in the TF sounding phase. Therefore, information about whether only TF sounding is performed after receiving the trigger frame or NDPA sounding continues after TF sounding is briefly indicated to the STA (e.g., sensing responder) receiving the trigger frame. method can be considered.

As described above, in order to indicate TF sounding only (eg, FIG. 17 (a)) and TF sounding + NDPA sounding (eg, FIG. 17 (b)), the sounding order/measurement configuration subfields are shown in the following table. It can be configured like 5 (e.g. 1-bit table).

value (bits)	contents
0	TF sounding
One	TF sounding + NDPA sounding

Referring to Table 5, TF sounding corresponding to a value of '0' is applied / set when only TF sounding is performed, or when TF sounding is performed after NDPA sounding (eg, 17 (d)) It can be.

Table 5 above is an example, and indication bits/values for each sounding phase configuration may be set differently.

Also, as described above in the present disclosure, sensing measurement may be performed using a plurality of measurement instances through one sensing measurement setup.

In this case, information for indicating that each measurement instance is performed within the same sensing measurement setup may be transmitted through a sensing trigger frame. That is, the information may be information indicating a sensing measurement setup to which a corresponding measurement instance belongs.

For example, to indicate that each measurement instance is performed within the same sensing measurement setup, the trigger dependent common information subfield included in the sensing trigger frame may include a measurement setup ID subfield.

The measurement setup ID subfield may consist of 3 or 4 bits, and as another example, may consist of 11 bits the same as the STA-ID. In addition, the name of the corresponding subfield is an example, and it is of course possible to change and use another subfield name.

Also, as described above in the present disclosure, information for indicating each measurement instance performed within the sensing measurement setup may be delivered through the sensing trigger frame. That is, the information may be information indicating which measurement instance the corresponding measurement instance corresponds to among one or more measurement instances in the sensing measurement setup.

For example, in order to indicate each measurement instance performed within the sensing measurement setup, a trigger dependent common information subfield included in the sensing trigger frame may include a measurement instance ID subfield. The name of the corresponding subfield is an example, and it is of course possible to change and use another subfield name.

The corresponding measurement instance ID subfield may be set identically to a sounding dialog token number transmitted through NDPA. Also, the corresponding measurement instance ID subfield may consist of 6 bits.

As shown in FIG. 17, one measurement instance may be configured in various ways according to a combination of a TF sounding phase and an NDPA sounding phase.

If the TF sounding phase starts first, the NDPA sounding dialog token number in the NDPA sounding performed subsequent to the TF sounding is set using the value of the measurement instance ID included in the trigger dependent common information subfield do. Conversely, in the case of starting with NDPA sounding, the measurement instance ID included in the trigger dependent common information subfield is set to the same value as the NDPA sounding dialog token number.

Therefore, the measurement instance ID may represent the sounding dialog token number included in the NDPA, or the value of the sounding dialog token number of the NDPA may be set using the value of the measurement instance ID.

In addition, as described above in the present disclosure, in a TB sensing measurement instance, a trigger frame may be transmitted to request NDP transmission to another STA (eg, a sensing responder). At this time, information for indicating a frame format for the corresponding NDP may be delivered through the corresponding trigger frame.

For example, the trigger dependent common information subfield of the sensing trigger frame may include a subfield indicating a frame format for an NDP to be transmitted by an STA (eg, a sensing responder).

An STA with wireless LAN sensing-related capabilities uses a previously defined NDP frame format (e.g., VHT, HE, EHT, etc.) and/or a new NDP frame format that has not yet been defined (e.g., radio to be defined later) for sensing measurement. It can be set/defined to use the LAN system (eg, NDP format of next wi-fi).

In this regard, a subfield indicating a frame format for NDP may consist of 2 bits or 3 bits.

For example, when a corresponding subfield consists of 2 bits, the corresponding subfield may be set as shown in Table 6 in consideration of the PPDU (or NDP) type/format requested/solicited through the sensing trigger frame.

value (bits)	contents
0 (B0B1=00)	VHT format
1 (B0B1=01)	HE format
2 (B0B1=10)	EHT format
3 (B0B1=11)	Reserved for other NDP formats

As another example, when a corresponding subfield consists of 2 bits, the corresponding subfield may be set as shown in Table 7 in consideration of the TB PPDU type/format.

value (bits)	contents
0 (B0B1=00)	HE TB format
1 (B0B1=01)	EHT TB format
2 (B0B1=10)	Reserved for other NDP formats
3 (B0B1=11)	Reserved for other NDP formats

Considering the above-described subfields related to the TB sensing measurement instance in the present disclosure, the trigger dependent common information subfield format for the sensing trigger variant may be set/defined as shown in FIG. 22 .

22 is a diagram illustrating an example of a trigger dependent common information subfield format in a sensing trigger frame according to the present disclosure.

Referring to FIG. 22, the trigger dependent common information subfield format for the sensing trigger variant includes a 3-bit/4-bit sensing trigger subtype subfield, a 3-bit/4-bit measurement setup ID subfield, and a 1-bit/2-bit sounding It may include a sequence/measurement configuration subfield, a 2-bit/3-bit PPDU format subfield, and a 6-bit measurement instance ID subfield.

22 illustrates a case in which all of the five subfields described above are included for convenience of description, but a format configuration including at least one of the five subfields described above is also possible based on the environment and/or setting. am.

The name of the corresponding subfield is an example, and it is of course possible to change and use another subfield name. In addition, the order of subfields included in the trigger dependent common information subfield corresponds to an example, and the order may be changed.

In addition, the number of bits of each subfield corresponds to an example and may be configured with a different number of bits.

According to various embodiments of the present disclosure described above, a sensing measurement process based on information sharing on a configuration of a TB sensing measurement instance can be efficiently and accurately performed.

The embodiments described above are those in which elements and features of the present disclosure are combined in a predetermined form. Each component or feature should be considered optional unless explicitly stated otherwise. Each component or feature may be implemented in a form not combined with other components or features. In addition, it is also possible to configure an embodiment of the present disclosure by combining some components and/or features. The order of operations described in the embodiments of the present disclosure may be changed. Some components or features of one embodiment may be included in another embodiment, or may be replaced with corresponding components or features of another embodiment. It is obvious that claims that do not have an explicit citation relationship in the claims can be combined to form an embodiment or can be included as new claims by amendment after filing.

It is apparent to those skilled in the art that the present disclosure may be embodied in other specific forms without departing from the essential features of the present disclosure. Accordingly, the foregoing detailed description should not be construed as limiting in all respects and should be considered illustrative. The scope of the present disclosure should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent range of the present disclosure are included in the scope of the present disclosure.

The scope of the present disclosure is software or machine-executable instructions (eg, operating systems, applications, firmware, programs, etc.) that cause operations in accordance with the methods of various embodiments to be executed on a device or computer, and such software or It includes a non-transitory computer-readable medium in which instructions and the like are stored and executable on a device or computer. Instructions that may be used to program a processing system that performs the features described in this disclosure may be stored on/in a storage medium or computer-readable storage medium and may be viewed using a computer program product that includes such storage medium. Features described in the disclosure may be implemented. The storage medium may include, but is not limited to, high speed random access memory such as DRAM, SRAM, DDR RAM or other random access solid state memory devices, one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or It may include non-volatile memory, such as other non-volatile solid state storage devices. The memory optionally includes one or more storage devices located remotely from the processor(s). The memory, or alternatively, the non-volatile memory device(s) within the memory includes non-transitory computer readable storage media. Features described in this disclosure may be stored on any one of the machine readable media to control hardware of a processing system and to allow the processing system to interact with other mechanisms that utilize results according to embodiments of the present disclosure. It may be integrated into software and/or firmware. Such software or firmware may include, but is not limited to, application code, device drivers, operating systems, and execution environments/containers.

The method proposed in the present disclosure has been described focusing on an example applied to an IEEE 802.11 based system, but it can be applied to various wireless LANs or wireless communication systems other than the IEEE 802.11 based system.

Claims (19)

1. A method performed by a first station (STA) in a wireless LAN system, the method comprising:

   Transmitting information related to a sequence of one or more sounding phases in a trigger based (TB) sensing measurement instance to one or more second STAs; and

   Performing the one or more sounding phases based on information related to the order within the TB sensing measurement instance,

   Information related to the order is transmitted through a trigger frame within the TB sensing measurement instance.
2. According to claim 1,

   The trigger frame is transmitted in a polling phase within the TB sensing measurement instance.
3. According to claim 1,

   Information related to the order is included in a trigger dependent common information subfield of the trigger frame.
4. According to claim 1,

   The one or more sounding phases include at least one of a trigger frame (TF) sounding phase or a null data packet announcement (NDPA) sounding phase.
5. According to claim 4,

   The information related to the order includes a first measurement instance type composed of only TF sounding phases, a second measurement instance type composed of TF sounding phases and NDPA sounding phases in order, and a third measurement instance type composed of NDPA sounding phases and TF sounding phases in order. Indicates one of a measurement instance type or a fourth measurement instance type consisting only of an NDPA sounding phase.
6. According to claim 4,

   The information related to the order may include a first measurement instance type composed of only the TF sounding phase, a second measurement instance type composed of the order of the TF sounding phase and the NDPA sounding phase, or the order of the NDPA sounding phase and the TF sounding phase. 3 Indicates one of the measurement instance types.
7. According to claim 4,

   The information related to the order includes information indicating whether an NDPA sounding phase following the TF sounding phase exists.
8. According to claim 1,

   The trigger frame includes information indicating a first sensing trigger subtype related to a polling phase or a second sensing trigger subtype related to a sounding phase.
9. According to claim 1,

   The trigger frame includes identification information for sensing measurement setup related to one or more TB sensing measurement instances including the TB sensing measurement instance.
10. According to claim 1,

    The trigger frame includes identification information for the TB sensing measurement instance.
11. According to claim 10,

    Based on the presence of an NDPA sounding phase following the TF sounding phase in the TB sensing measurement instance, the value of the sounding dialog token number related to the NDPA sounding phase is the TB sensing measurement instance Is set to the same value as the identification information for, method.
12. According to claim 10,

    Based on the existence of a TF sounding phase following the NDPA sounding phase in the TB sensing measurement instance, the value of the identification information for the TB sensing measurement instance is the same as the sounding dialog token number related to the NDPA sounding phase A method that is set to a value.
13. According to claim 1,

    The first STA is a sensing initiator, and the second STA is a sensing responder.
14. According to claim 1,

    The trigger frame includes bit information for distinguishing a ranging purpose from a sensing purpose.
15. In a first station (STA) device in a wireless LAN system, the STA device:

    one or more transceivers; and

    one or more processors coupled to the one or more transceivers;

    The one or more processors:

    Transmit information related to a sequence of one or more sounding phases in a trigger based (TB) sensing measurement instance to one or more second STAs;

    Set to perform the one or more sounding phases based on information related to the order in the TB sensing measurement instance,

    The information related to the order is transmitted through a trigger frame within the TB sensing measurement instance.
16. A method performed by a second station (STA) in a wireless LAN system, the method comprising:

    Receiving information related to a sequence of one or more sounding phases in a trigger based (TB) sensing measurement instance from a first STA; and

    Performing the one or more sounding phases based on information related to the order within the TB sensing measurement instance,

    Information related to the order is received through a trigger frame within the TB sensing measurement instance.
17. In a second station (STA) device in a wireless LAN system, the device comprises:

    one or more transceivers; and

    one or more processors coupled to the one or more transceivers;

    The one or more processors:

    Receive information related to a sequence of one or more sounding phases in a trigger based (TB) sensing measurement instance from the first STA;

    Set to perform the one or more sounding phases based on information related to the order in the TB sensing measurement instance,

    The information related to the order is received through a trigger frame within the TB sensing measurement instance.
18. A processing device configured to control a station (STA) in a wireless LAN system, the processing device comprising:

    one or more processors; and

    A processing device comprising one or more computer memories operatively connected to the one or more processors and storing instructions for performing the method according to claim 1 upon being executed by the one or more processors.
19. one or more non-transitory computer readable media storing one or more instructions, comprising:

    The one or more instructions are executed by one or more processors to control a device to perform the method according to claim 1 in a wireless LAN system.

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