Method and apparatus for transmitting or receiving in enhanced trigger transmission opportunity sharing process in wireless LAN system

Abstract

Disclosed are a method and an apparatus for transmitting or receiving in an enhanced trigger transmission opportunity sharing procedure in a wireless LAN system. According to one embodiment of the present disclosure, a method performed by an STA in a wireless LAN system may comprise the steps of: receiving, from an AP, a trigger frame related to sharing of a TXOP; sending a response frame for the trigger frame to the AP; and performing a frame exchange with another STA in the time interval allocated to the STA based on the trigger frame. A TXOP sharing mode subfield included in the trigger frame may be set to a value indicating a TXOP sharing mode for allocating a time interval such that a frame exchange is performed between the STA and another STA. A duration of a frame transmitted in a time interval allocated to the STA may be set based on an end point of the TXOP or an end point of the frame exchange.

Description

Technical Field

[0001] This disclosure relates to methods and apparatus for transmitting or receiving during enhanced triggered transmission opportunity (TXOP) sharing in a wireless local area network (WLAN) system. Background Technology

[0002] New technologies have been introduced for Wireless LANs (WLANs) to improve transmission rates, increase bandwidth, enhance reliability, reduce errors, and decrease latency. Within WLAN technology, the IEEE 802.11 series of standards can be referred to as Wi-Fi. For example, recent technologies introduced into WLAN include the Ultra High Throughput (VHT) enhancement of the 802.11 ac standard and the High Efficiency (HE) enhancement of the IEEE 802.11 ax standard.

[0003] To provide a more advanced wireless communication environment, improved techniques for Extremely High Throughput (EHT) are being discussed. For example, techniques for MIMO and multiple access point (AP) coordination that support increased bandwidth, efficient use of multiple frequency bands, and increased spatial flow are being investigated. Specifically, various techniques are being explored to support low-latency or real-time services. Furthermore, new technologies to support Ultra-High Reliability (UHR), including improvements or extensions to EHT techniques, are being discussed. Summary of the Invention

[0004] Technical issues

[0005] The technical objective of this disclosure is to provide a method and apparatus for transmitting or receiving data during enhanced triggered transmission opportunity (TXOP) sharing in a wireless WLAN system.

[0006] Another technical objective of this disclosure is to provide a method and apparatus for supporting multiple peer-to-peer (P2P) communications in a wireless LAN system during the Triggered Transmission Opportunity (TXOP) sharing process.

[0007] The additional technical objective of this disclosure is to provide a method and apparatus for configuring the duration of frames transmitted and received within a shared triggered transmission opportunity (TXOP).

[0008] The technical objectives to be achieved by this disclosure are not limited to those described above, and other technical objectives not described herein will be clearly understood by those skilled in the art through the following description.

[0009] Technical solution

[0010] According to one aspect of this disclosure, a method performed by a station (STA) in a wireless LAN system may include: receiving a trigger frame associated with sharing a transmission opportunity (TXOP) from an access point (AP); transmitting a response frame to the trigger frame to the AP; and performing a frame exchange with another STA within a time period allocated to the STA based on the trigger frame. Herein, a TXOP sharing mode subfield included in the trigger frame may be set to a value indicating a TXOP sharing mode used to allocate a time period for performing frame exchange between the STA and another STA. In this case, the duration of frames transmitted within the time period allocated to the STA may be set based on the end timing of the TXOP or the end timing of the frame exchange.

[0011] According to an additional aspect of this disclosure, a method performed by an access point (AP) in a wireless LAN system may include: receiving a trigger frame associated with sharing a transmission opportunity (TXOP) to a plurality of stations (STAs); and receiving a response frame for the trigger frame from one or more of the plurality of STAs. Herein, a TXOP sharing mode subfield included in the trigger frame may be set to a value indicating a TXOP sharing mode used to allocate a time period for performing frame exchange between STAs belonging to the plurality of STAs and STAs not belonging to the plurality of STAs. In this case, since the frame exchange is performed within the time period allocated based on the trigger frame, the duration of frames transmitted within that time period may be set based on the end timing of the TXOP or the end timing of the frame exchange.

[0012] Technical effect

[0013] According to this disclosure, methods and apparatus may be provided for transmitting or receiving in a wireless LAN system during enhanced trigger transmission opportunity sharing.

[0014] According to this disclosure, a method and apparatus may be provided for supporting multiple P2P communications in a wireless LAN system during the triggering of transmission opportunity sharing.

[0015] According to this disclosure, a method and apparatus may be provided for performing P2P communication on demand by multiple stations (STAs) in a wireless LAN system.

[0016] According to this disclosure, P2P transmission can be performed for multiple users / stations in a transmission opportunity sharing mode triggered in any situation where a network allocation vector (NAV) can be set.

[0017] The effects achievable by this disclosure are not limited to those described above, and those skilled in the art can clearly understand other effects not described herein through the following description. Attached Figure Description

[0018] The accompanying drawings, which are included as part of the detailed description of this disclosure, provide embodiments of the disclosure and, together with the detailed description, describe the technical features of the disclosure.

[0019] Figure 1 A configuration block diagram of a wireless communication device according to an embodiment of the present disclosure is illustrated.

[0020] Figure 2 This is a diagram illustrating an exemplary structure of a WLAN system to which this disclosure can be applied.

[0021] Figure 3 This is a diagram used to illustrate the link establishment process that can be applied to this disclosure.

[0022] Figure 4 This is a diagram used to illustrate the backoff processing that can be applied to this disclosure.

[0023] Figure 5 This is a diagram illustrating the CSMA / CA-based frame transmission operation that can be applied to this disclosure.

[0024] Figure 6 This is a diagram illustrating an example of a frame structure that can be used in a WLAN system to which this disclosure may be applied.

[0025] Figure 7 This is a diagram illustrating an example of a PPDU as defined in the IEEE 802.11 standard of this disclosure.

[0026] Figure 8 This is a diagram illustrating an exemplary format of the trigger frame to which the present disclosure may be applied.

[0027] Figure 9 This is a diagram used to explain an example of how the TXOP sharing process can be triggered by applying this disclosure.

[0028] Figure 10 This is a diagram used to explain the operation of the STA during the triggering of TXOP sharing according to this disclosure.

[0029] Figure 11 This is a diagram used to explain the operation of the AP during the triggering of TXOP sharing according to this disclosure.

[0030] Figure 12 This is a diagram used to explain an example of triggering the TXOP sharing process according to the examples in this disclosure.

[0031] Figure 13 This is a diagram used to explain an example of triggering the TXOP sharing process according to another example of this disclosure.

[0032] Figure 14This is a diagram used to explain an example of triggering the TXOP sharing process according to another example of this disclosure.

[0033] Figure 15 This is a diagram used to explain the triggering of the TXOP sharing process according to another example of this disclosure.

[0034] Figure 16 This is a diagram used to explain the triggering of the TXOP sharing process according to another example of this disclosure.

[0035] Figure 17 An example of setting the duration of a frame based on a P2P operation according to an embodiment of the present disclosure is illustrated.

[0036] Figure 18 Another example of setting the duration of a frame based on a P2P operation according to an embodiment of the present disclosure is illustrated. Detailed Implementation

[0037] In the following, embodiments according to this disclosure will be described in detail with reference to the accompanying drawings. The detailed description disclosed with reference to the drawings is intended to describe exemplary embodiments of this disclosure and not to represent the only embodiments in which this disclosure can be implemented. The following detailed description includes specific details to provide a complete understanding of this disclosure. However, those skilled in the art will recognize that this disclosure can be implemented without these specific details.

[0038] In some cases, known structures and devices may be omitted, or they may be shown in block diagram form based on the core functions of each structure and device in order to prevent ambiguity in the concepts of this disclosure.

[0039] In this disclosure, when an element is referred to as “connected,” “combined,” or “linked” to another element, it can include both indirect and direct connections between the two elements. Furthermore, in this disclosure, the terms “comprising” or “having” specify the presence of the mentioned features, steps, operations, components, and / or elements, but do not exclude the presence or addition of one or more other features, stages, operations, components, elements, and / or groups thereof.

[0040] In this disclosure, terms such as "first" and "second" are used only to distinguish one element from another and are not used to limit the elements. Unless otherwise stated, they do not limit the order or importance of the elements. Therefore, within the scope of this disclosure, a first element in one embodiment may be referred to as a second element in another embodiment, and similarly, a second element in one embodiment may be referred to as a first element in another embodiment.

[0041] The terminology used in this disclosure is for the purpose of describing particular embodiments and not for limiting the claims. As used in the description of embodiments and the appended claims, the singular form is intended to include the plural form unless the context clearly indicates otherwise. The term “and / or” as used in this disclosure may refer to one of the associated enumerations, or is intended to refer to and include any and all possible combinations of two or more of them. Furthermore, unless otherwise stated, the “ / ” between words in this disclosure has the same meaning as “and / or”.

[0042] The examples disclosed herein can be applied to various wireless communication systems. For example, the examples disclosed herein can be applied to wireless LAN systems. For example, the examples disclosed herein can be applied to wireless LANs based on the IEEE 802.11a / g / n / ac / ax standards. Furthermore, the examples disclosed herein can be applied to wireless LANs based on the newly proposed IEEE 802.11be (or EHT) standard. The examples disclosed herein can be applied to wireless LANs based on the IEEE 802.11be version 2 standard, corresponding to the additional enhancements of the IEEE 802.11be version 1 standard. Additionally, the examples disclosed herein can be applied to wireless LANs based on next-generation standards following IEEE 802.11be. Furthermore, the examples disclosed herein can be applied to cellular wireless communication systems. For example, it can be applied to cellular wireless communication systems based on 3GPP standards using Long Term Evolution (LTE) technology and 5G New Radio (NR) technology.

[0043] The technical features that can be applied to examples of this disclosure will be described below.

[0044] Figure 1 A block diagram illustrating a wireless communication device according to an embodiment of the present disclosure is shown.

[0045] Figure 1 The first device 100 and the second device 200 illustrated herein can be replaced by various terms such as terminal, wireless device, wireless transceiver unit (WTRU), user equipment (UE), mobile station (MS), user terminal (UT), mobile subscriber station (MSS), mobile subscriber unit (MSU), subscriber station (SS), advanced mobile station (AMS), wireless terminal (WT), or simply user. Furthermore, the first device 100 and the second device 200 include access point (AP), base station (BS), fixed station, node B, base transceiver system (BTS), and network. It can be replaced by various terms such as artificial intelligence (AI) system, roadside unit (RSU), repeater, router, relay, and gateway.

[0046] Figure 1The devices 100 and 200 illustrated herein may be referred to as stations (STAs). For example, Figure 1 The devices 100 and 200 illustrated herein may be referred to by various terms such as transmitting device, receiving device, transmitting STA, and receiving STA. For example, STA 110 and 200 may perform an access point (AP) role or a non-AP role. That is, in this disclosure, STA 110 and 200 may perform AP and / or non-AP functions. When STA 110 and 200 perform AP functions, they may simply be referred to as APs, and when STA 110 and 200 perform non-AP functions, they may simply be referred to as STAs. Alternatively, in this disclosure, AP may also be referred to as AP STA.

[0047] Reference Figure 1 The first device 100 and the second device 200 can transmit and receive radio signals via various wireless LAN technologies (e.g., IEEE 802.11 series). The first device 100 and the second device 200 may include interfaces for the Media Access Control (MAC) layer and Physical Layer (PHY) conforming to the IEEE 802.11 standard.

[0048] In addition to wireless LAN technology, the first device 100 and the second device 200 can also support various communication standards (e.g., 3GPP LTE series, 5G NR series standards, etc.). Furthermore, the devices disclosed herein can be implemented in various devices such as mobile phones, vehicles, personal computers, augmented reality (AR) devices, and virtual reality (VR) devices. Additionally, the STA of this specification can support various communication services such as voice calls, video calls, data communication, autonomous driving, machine-type communication (MTC), machine-to-machine (M2M), device-to-device (D2D), and IoT (Internet of Things).

[0049] The first device 100 may include 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 processors 102 may control the memories 104 and / or the transceivers 106, and may be configured to implement the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure. For example, the processor 102 may transmit a wireless signal including the first information / signal via the transceivers 106 after generating first information / signal by processing information in the memories 104. Additionally, the processor 102 may receive a wireless signal including second information / signal via the transceivers 106, and then store information obtained through signal processing of the second information / signal in the memories 104. The memories 104 may be connected to the processor 102 and may store various information related to the operation of the processor 102. For example, the memories 104 may store software code including instructions for performing all or part of the processing controlled by the processor 102 or for performing the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure. Here, processor 102 and memory 104 may be part of a communication modem / circuit / chip designed to implement wireless LAN technology (e.g., IEEE 802.11 series). Transceiver 106 may be connected to processor 102 and may transmit and / or receive wireless signals via one or more antennas 108. Transceiver 106 may include a transmitter and / or a receiver. Transceiver 106 may be used with an RF (radio frequency) unit. In this disclosure, wireless device may refer to a communication modem / circuit / chip.

[0050] The second device 200 may include one or more processors 202 and one or more memories 204, and may additionally include one or more transceivers 206 and / or one or more antennas 208. The processors 202 may control the memories 204 and / or the transceivers 206, and may be configured to implement the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure. For example, the processors 202 may generate third information / signals by processing information in the memories 204, and then transmit a wireless signal including the third information / signals via the transceivers 206. Additionally, the processors 202 may receive wireless signals including fourth information / signals via the transceivers 206, and then store information obtained through signal processing of the fourth information / signals in the memories 204. The memories 204 may be connected to the processors 202 and may store various information related to the operation of the processors 202. For example, the memories 204 may store software code including instructions for performing all or part of the processing controlled by the processors 202 or for performing the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure. Here, processor 202 and memory 204 may be part of a communication modem / circuit / chip designed to implement wireless LAN technology (e.g., IEEE 802.11 series). Transceiver 206 may be connected to processor 202 and may transmit and / or receive wireless signals via one or more antennas 208. Transceiver 206 may include a transmitter and / or a receiver. Transceiver 206 may be used with an RF unit. In this disclosure, apparatus may refer to a communication modem / circuit / chip.

[0051] The hardware elements of devices 100 and 200 will be described in more detail below. Not limited thereto, one or more protocol layers may be implemented by one or more processors 102 and 202. For example, one or more processors 102 and 202 may implement one or more layers (e.g., functional layers such as PHY and MAC). One or more processors 102 and 202 may generate one or more PDUs (Protocol Data Units) and / or one or more SDUs (Service Data Units) according to the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts disclosed in this disclosure. One or more processors 102 and 202 may generate messages, control information, data, or information according to the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts disclosed in this disclosure. One or more processors 102 and 202 may generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the functions, processes, suggestions, and / or methods disclosed in this disclosure to provide them to one or more transceivers 106 and 206. One or more processors 102, 202 may receive signals (e.g., baseband signals) from one or more transceivers 106, 206 and obtain PDUs, SDUs, messages, control information, data or information, in accordance with the description, functions, processes, suggestions, methods and / or operation flowcharts included in this disclosure.

[0052] One or more processors 102, 202 may be referred to as controllers, microcontrollers, microprocessors, or microcomputers. One or more processors 102, 202 may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more ASICs (Application-Specific Integrated Circuits), one or more DSPs (Digital Signal Processors), one or more DSPDs (Digital Signal Processing Devices), one or more PLDs (Programmable Logic Devices), or one or more FPGAs (Field-Programmable Gate Arrays) may be included in one or more processors 102, 202. The descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure may be implemented using firmware or software, and the firmware or software may be implemented to include modules, processes, functions, etc. Firmware or software configured to execute the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure may be included in one or more processors 102, 202, or may be stored in one or more memories 104, 204 and driven by one or more processors 102, 202. The descriptions, functions, processes, suggestions, methods and / or operation flowcharts included in this disclosure may be implemented using firmware or software in the form of code, instructions and / or instruction sets.

[0053] One or more memories 104, 204 may be connected to one or more processors 102, 202 and may store data, signals, messages, information, programs, code, instructions, and / or commands in various forms. One or more memories 104, 204 may be configured with ROM, RAM, EPROM, flash memory, hard disk drive, registers, cache memory, computer-readable storage media, and / or combinations thereof. One or more memories 104, 204 may be located internally and / or externally to one or more processors 102, 202. Furthermore, one or more memories 104, 204 may be connected to one or more processors 102, 202 via various technologies such as wired or wireless connections.

[0054] One or more transceivers 106, 206 can transmit user data, control information, wireless signals / channels, etc., mentioned in the methods and / or operation flowcharts of this disclosure to one or more other devices. One or more transceivers 106, 206 can receive user data, control information, wireless signals / channels, etc., mentioned in the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure from one or more other devices. For example, one or more transceivers 106, 206 can be connected to one or more processors 102, 202 and can transmit and receive wireless signals. For example, one or more processors 102, 202 can control one or more transceivers 106, 206 to transmit user data, control information, or wireless signals to one or more other devices. Additionally, one or more processors 102, 202 can control one or more transceivers 106, 206 to receive user data, control information, or wireless signals from one or more other devices. Additionally, one or more transceivers 106, 206 may be connected to one or more antennas 108, 208, and one or more transceivers 106, 206 may be configured to transmit and receive user data, control information, wireless signals / channels, etc., mentioned in the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure, via one or more antennas 108, 208. In this disclosure, one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers 106, 206 may convert received wireless signals / channels, etc., from RF band signals into baseband signals for processing using one or more processors 102, 202. One or more transceivers 106, 206 may convert user data, control information, wireless signals / channels, etc., processed using one or more processors 102, 202, from baseband signals into RF band signals. Therefore, one or more transceivers 106, 206 may include (analog) oscillators and / or filters.

[0055] For example, one of STAs 100 and 200 can perform the expected operation of an AP, and the other of STAs 100 and 200 can perform the expected operation of a non-AP STA. For example, Figure 1 Transceivers 106 and 206 can perform transmission and reception operations of signals (e.g., packet or physical layer protocol data units (PPDUs) conforming to IEEE 802.11a / b / g / n / ac / ax / be / bn). Additionally, in this disclosure, the various STAs can generate transmit / receive signals or perform data processing or calculations on the transmit / receive signals in advance by [the relevant entity / component]. Figure 1Processors 102 and 202 perform the following operations: For example, examples of generating transmit / receive signals or performing data processing or computations on transmit / receive signals in advance may include: 1) determining / acquiring / configuring / computing / decoding / encoding bit information of fields (signals (SIG), short training field (STF), long training field (LTF), data, etc.) included in the PPDU; 2) determining / configuring / acquiring time or frequency resources (e.g., subcarrier resources) for the fields (SIG, STF, LTF, data, etc.) included in the PPDU; 3) determining / configuring / acquiring specific sequences (e.g., pilot sequences, STF / LTF sequences, additional sequences applied to SIG) for the fields (SIG, STF, LTF, data, etc.) included in the PPDU action; 4) power control operations and / or power saving operations applied to the STA; 5) operations related to determining / acquiring / configuring / computing / decoding / encoding of the ACK signal. Additionally, in the example below, various information used by different STAs to determine / acquire / configure / calculate / decode / encode transmitted and received signals (e.g., information related to fields / subfields / control fields / parameters / power, etc.) can be stored. Figure 1 In memory 104 and 204.

[0056] In the following text, downlink (DL) can refer to a link used for communication from an AP STA to a non-AP STA, and DL PPDU / packets / signals can be sent and received via DL. In DL communication, the transmitter can be part of an AP STA, and the receiver can be part of a non-AP STA. Uplink (UL) can refer to a link used for communication from a non-AP STA to an AP STA, and UL PPDU / packets / signals can be sent and received via UL. In UL communication, the transmitter can be part of a non-AP STA, and the receiver can be part of an AP STA.

[0057] Figure 2 This is a diagram illustrating an exemplary structure of a wireless LAN system to which this disclosure can be applied.

[0058] A wireless LAN system can be structured by multiple components. These components interact to provide STA mobility support that is transparent to upper layers. The Basic Service Set (BSS) corresponds to the basic building blocks of a wireless LAN. Figure 2 An example is shown where there are two BSSs (BSS1 and BSS2), and two STAs included as members of each BSS (STA1 and STA2 are included in BSS1, and STA3 and STA4 are included in BSS2). Figure 2The ellipse representing the BSS can also be interpreted as representing the coverage area within the corresponding BSS where STAs maintain communication. This area can be called the Basic Service Area (BSA). When a STA moves outside the BSA, it cannot communicate directly with other STAs within the BSA.

[0059] If we do not consider Figure 2 The DS shown in the diagram represents the most basic BSS type in a wireless LAN: the Independent BSS (IBSS). For example, an IBSS can have a minimal form containing only two STAs. For instance, assuming other components are omitted, BSS1 containing only STA1 and STA2, or BSS2 containing only STA3 and STA4, can respectively correspond to representative examples of IBSS. This configuration is possible when STAs can communicate directly without an AP. Furthermore, in this type of wireless LAN, it is not pre-configured but can be configured as needed, and this can be called an ad-hoc network. Since an IBSS does not include an AP, there is no centralized management entity. That is, in an IBSS, STAs are managed in a distributed manner. In an IBSS, all STAs can consist of mobile STAs and are not allowed to access the Distributed System (DS), thus forming a self-contained network.

[0060] Membership of an STA in a BSS can be dynamically changed by opening or closing an STA, or by entering or leaving a BSS zone. To become a member of a BSS, an STA can join the BSS using a synchronization process. To access all services of the BSS infrastructure, an STA must be associated with the BSS. This association can be dynamically established and may include the use of Distributed System Services (DSS).

[0061] Direct STA-to-STA distance in a wireless LAN may be limited by PHY performance. In some cases, this distance limitation may be sufficient, but in others, longer distances between STAs may be required for communication. Distributed systems (DS) can be configured to support extended coverage.

[0062] DS refers to the structure of BSS interconnection. Specifically, such as... Figure 2As shown, a BSS can exist as an extension of a network composed of multiple BSSs. A DS is a logical concept and can be specified through the characteristics of the Distributed System Medium (DSM). At this point, the Wireless Medium (WM) and the DSM can be logically separated. Each logical medium is used for a different purpose and 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 a wireless LAN architecture (DS architecture or other network architectures) can be interpreted as multiple media being logically different. That is, a wireless LAN architecture can be implemented in various ways, and the corresponding wireless LAN architecture can be independently specified by the physical characteristics of each implementation.

[0063] The DS can support mobile devices by providing seamless integration of multiple BSSs and offering the logical services necessary for addressing to the destination. Additionally, the DS may include a component called a portal, which acts as a bridge between the wireless LAN and other networks, such as IEEE 802.X.

[0064] AP enables access to DS via WM for associated non-AP STAs, and refers to entities that also have STA functionality. Data movement between BSS and DS can be performed through AP. For example, Figure 2 STA2 and STA3, shown in the diagram, have the functionality of STAs and provide the ability for associated non-AP STAs (STA1 and STA4) to access the DS. Furthermore, since all APs essentially correspond to STAs, all APs are addressable entities. The address used by an AP for communication on the WM is not necessarily the same as the address used by the AP for communication on the DSM. A BSS consisting of APs and one or more STAs can be referred to as an infrastructure BSS.

[0065] Data sent from one of the STAs associated with the AP to the corresponding STA address of the AP can always be received on an uncontrolled port and can be processed by the IEEE 802.1X port access entity. Alternatively, when the controlled port is authenticated, the transmitted data (or frames) can be delivered to the DS.

[0066] In addition to the DS structure described above, Extended Service Sets (ESS) can also be configured to provide wide coverage.

[0067] An ESS (Service Set Identity) refers to a network of arbitrary size and complexity consisting of DS (Service Controller) and BSS (Service Set Service). An ESS can correspond to a set of BSSs connected to a DS. However, an ESS does not include the DS. An ESS network is characterized as an IBSS (Integrated Service Set Service) within the Logical Link Control (LLC) layer. STAs included in an ESS can communicate with each other, and a moving STA can transparently move from one BSS to another (within the same ESS) to the LLC. APs included in an ESS can have the same Service Set Identity (SSID). The SSID is distinguished from the BSSID, which serves as the identifier for the BSS.

[0068] Wireless LAN systems make no assumptions about the relative physical locations of BSSs, and all of the following forms are possible. BSSs can partially overlap, a form commonly used to provide continuous coverage. Additionally, BSSs may not be physically connected, and logically, there is no limit to the distance between BSSs. Furthermore, BSSs can be physically located in the same location, which can be used to provide redundancy. Additionally, one (or more) IBSS or ESS networks can physically exist in the same space as one (or more) ESS networks. This can correspond to the form of ESS networks 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, etc.

[0069] Figure 3 This is a diagram illustrating the link establishment process that can be applied to this disclosure.

[0070] In order for a STA to establish a link with the network and send / receive data, it first discovers the network, performs authentication, establishes an association, and performs authentication processing for security. The link establishment process can also be called session initiation processing or session establishment processing. Furthermore, the discovery, authentication, association, and security establishment processes of the link establishment process can be collectively referred to as association processing.

[0071] In step S310, the STA can perform a network discovery operation. The network discovery operation may include a scanning operation by the STA. That is, in order for the STA to access a network, it needs to find networks it can participate in. The STA should identify compatible networks before participating in a wireless network, and the process of identifying networks existing in a specific area is called scanning.

[0072] Scanning schemes include active scanning and passive scanning. Figure 3An exemplary network discovery operation including active scanning processing is illustrated. In active scanning, the STA performing the scan sends a probe request frame to discover which APs are present around it as the channel moves and awaits a response. The responder sends a probe response frame as a response to the probe request frame to the STA that sent the probe request frame. Here, the responder may be the STA that last sent a beacon frame in the BSS of the channel being scanned. In the BSS, the AP becomes the responder because it sends a beacon frame, and in the IBSS, the STAs in the IBSS rotate to send beacon frames, so the responder is not constant. For example, an STA that sends a probe request frame on channel 1 and receives a probe response frame on channel 1 may store the BSS-related information included in the received probe response frame and may move to the next channel (e.g., channel 2) and perform a scan in the same manner (i.e., sending and receiving probe requests / responses on channel 2).

[0073] Although not in Figure 3 As shown, scanning can be performed passively. In passive scanning, the STA performing the scan waits for beacon frames while moving through the channel. Beacon frames are one of the management frames defined in IEEE 802.11 and are sent periodically to notify of the existence of a wireless network and allow the STA performing the scan to find and participate in the wireless network. In the BSS, the AP periodically sends beacon frames, and in the IBSS, the STA within the IBSS rotates to send beacon frames. When the STA performing the scan receives a beacon frame, it stores the BSS information included in the beacon frame and records the beacon frame information for each channel while moving to another channel. The STA receiving the beacon frame can store the BSS-related information included in the received beacon frame, move to the next channel, and perform scanning in the next channel in the same manner. Comparing active and passive scanning, active scanning has the advantages of less latency and less power consumption.

[0074] After the STA discovers the network, an authentication process can be performed in step S320. To clearly distinguish it from the security establishment operation in step S340, which will be described later, this authentication process can be referred to as the first authentication process.

[0075] The authentication process includes the following steps: the STA sends an authentication request frame to the AP, and in response, the AP sends an authentication response frame to the STA. The authentication frame used for the authentication request / response corresponds to the management frame.

[0076] An authentication frame includes the authentication algorithm number, authentication transaction sequence number, status code, challenge text, robust security network (RSN), and finite circular group. These correspond to some examples of information that can be included in the authentication request / response frame and can be replaced with other information, or additional information may be included.

[0077] A STA can send an authentication request frame to an AP. The AP can determine whether to allow the corresponding STA's authentication based on the information included in the received authentication request frame. The AP can then provide the STA with the authentication processing result via an authentication response frame.

[0078] After the STA is successfully authenticated, the association process can be performed in step S330. The association process includes the following steps: the STA sends an association request frame to the AP, and in response, the AP sends an association response frame to the STA.

[0079] For example, an association request frame may include information related to various capabilities, beacon listening intervals, service set identifiers (SSIDs), supported rates, supported channels, RSNs, mobile domains, supported operation classes, service indication mapping broadcast requests (TIM broadcast requests), interoperability capabilities, etc. Similarly, an association response frame may include information related to various capabilities, status codes, association IDs (AIDs), supported rates, enhanced distributed channel access (EDCA) parameter sets, received channel power indicators (RCPIs), received signal-to-noise ratio indicators (RSNIs), mobile domains, timeout intervals (e.g., association recovery time), overlapping BSS scan parameters, TIM broadcast responses, quality of service (QoS) mappings, etc. These correspond to some examples of information that can be included in association request / response frames and may be replaced with other information, or additional information may be included.

[0080] After the STA successfully associates with the network, a security establishment process can be performed in step S340. The security establishment process in step S340 can be referred to as the authentication process via a Robust Secure Network Association (RSNA) request / response, the authentication process in step S320 is referred to as the first authentication process, and the security establishment process in step S340 can also be simply referred to as the authentication process.

[0081] The secure establishment process in step S340 may include, for example, the process of establishing a private key using a four-way handshake via Extensible Authentication Protocol (EAPOL) frames over the LAN. Alternatively, the secure establishment process may be performed according to a security scheme not defined in the IEEE 802.11 standard.

[0082] Figure 4 This is a diagram illustrating the fallback process that can be applied to this disclosure.

[0083] In wireless LAN systems, the basic access mechanism for Media Access Control (MAC) is Carrier Sensing Multiple Access with Collision Avoidance (CSMA / CA). Also known as the Distributed Coordination Function (DCF) of IEEE 802.11 MAC, CSMA / CA essentially employs a "listen-before-talk" access mechanism. Under this type of access mechanism, before commencing transmission, the AP and / or STA can perform a Net Channel Assessment (CCA) of the sensing radio channel or medium during a predetermined time interval (e.g., the DCF inter-frame interval (DIFS)). As a result of the sensing, if the medium is determined to be idle, frame transmission begins via the corresponding medium. Conversely, if the medium is detected to be occupied or busy, the corresponding AP and / or STA does not begin its own transmission and can set a delay period for medium access (e.g., a random backoff period) and attempt frame transmission after waiting. By applying a random backoff period, collisions can be minimized because multiple STAs are expected to attempt frame transmission after waiting for different time periods.

[0084] In addition, the IEEE 802.11 MAC protocol provides a Hybrid Coordination Function (HCF). HCF is based on DCF and Point Coordination Function (PCF). PCF is a polling-based synchronous access method, meaning that all receiving APs and / or STAs periodically poll to receive data frames. Furthermore, HCF includes Enhanced Distributed Channel Access (EDCA) and HCF Control Channel Access (HCCA). EDCA is a contention-based access method that provides data frames to multiple users, while HCCA uses a non-contention-based channel access method that utilizes a polling mechanism. Additionally, HCF includes a media access mechanism for improving the QoS (Quality of Service) of wireless LANs and can transmit QoS data during contention periods (CP) and contention-free periods (CFP).

[0085] Reference Figure 4 This section describes the operation based on a random backoff period. When an occupied / busy medium becomes idle, multiple STAs can attempt to transmit data (or frames). As a method to minimize collisions, each STA can individually select a random backoff count and attempt to transmit after waiting for the corresponding time slot. The random backoff count has a pseudo-random integer value and can be determined as one of the values ​​ranging from 0 to CW. Here, CW is the contention window parameter value. The CW parameter is assigned an initial value of CWmin, but can take a value twice as large as in the event of transmission failure (e.g., when no ACK is received for the transmitted frame). When the CW parameter value reaches CWmax, data transmission can be attempted while maintaining the CWmax value until successful data transmission, and when successful, the CWmin value is reset. The values ​​of CW, CWmin, and CWmax are preferably set to 2.n -1 (n=0, 1, 2,...).

[0086] When random backoff processing begins, the STA continuously monitors the medium during the backoff time slot countdown based on the determined backoff count value. When monitoring the medium for occupancy, it stops the countdown and waits, and restarts the remainder of the countdown when the medium becomes idle.

[0087] exist Figure 4 In the example, when the packet to be sent arrives at STA 3's MAC, STA 3 can send the frame immediately after confirming that the medium has been idle for up to DIFS. The remaining STAs monitor and wait for the medium to be occupied / busy. Meanwhile, the data to be sent can also occur in each of STA 1, STA 2, and STA 5, and when the medium is detected as idle, each STA waits for up to DIFS, and then performs a countdown for the backoff slot based on a random backoff count value chosen by each STA. Assume STA 2 chooses the minimum backoff count value, and STA 1 chooses the maximum backoff count value. That is, the example illustrates the case where STA 5's remaining backoff time is shorter than STA 1's remaining backoff time when STA 2 completes its backoff count and begins frame transmission. STA 1 and STA 5 temporarily stop the countdown and wait while STA 2 occupies the medium. When STA 2's occupancy ends and the medium becomes idle again, STA 1 and STA 5 wait for DIFS and restart the stopped backoff count. In other words, frame transmission can begin after a countdown for the remaining backoff slot based on the remaining backoff time. Since STA5 has a shorter remaining backoff time than STA1, STA5 begins frame transmission. Data to be transmitted can also occur in STA4 while STA2 is occupying the medium. From STA4's perspective, when the medium becomes idle, STA4 can wait for DIFS, then execute a countdown based on a random backoff count value selected by STA4, and begin transmitting frames. Figure 4 The example illustrates a scenario where the remaining backoff time of STA5 accidentally conflicts with the random backoff count value of STA4. In this case, a collision may occur between STA4 and STA5. When a collision occurs, neither STA4 nor STA5 receives an ACK, so data transmission fails. In this situation, STA4 and STA5 can double the CW value, select a random backoff count value, and begin a countdown. While the medium is occupied due to the transmissions of STA4 and STA5, STA1 waits; when the medium becomes idle, STA1 waits for DIFS, and then begins frame transmission after the remaining backoff time has elapsed.

[0088] As in Figure 4In the example, data frames are frames used to send data forwarded to higher layers and can be sent after a backoff performed after DIFS, starting from when the medium becomes idle. Additionally, management frames are frames used to exchange management information that has not been forwarded to higher layers and are sent after a backoff performed after an IFS such as DIFS or Point Coordination Function IFS (PIFS). Subtypes of management frames include beacons, association requests / responses, reassociation requests / responses, probe requests / responses, authentication requests / responses, etc. Control frames are frames used to control access to the medium. Subtypes of control frames include Request to Send (RTS), Allow to Send (CTS), Acknowledge (ACK), Power Saving Poll (PS-Poll), Block Acknowledge (BlockAck), Block Acknowledge Request (BlockACKReq), Null Data Packet Announcement (NDP Announcement), and Trigger, etc. If a control frame is not a response frame to the previous frame, it is sent after a backoff performed after DIFS; if it is a response frame to the previous frame, it is sent without a backoff performed after a Short IFS (SIFS). The type and subtype of a frame can be identified by the type field and subtype field in the Frame Control (FC) field.

[0089] The Quality of Service (QoS) ST can perform a backoff following the Arbitration IFS (AIFS) for the Access Class (AC) to which the frame belongs (i.e., AIFS where i is a value determined by the AC) before the frame can be transmitted. Here, the frame that can use AIFS can be a data frame, management frame, or control frame, rather than a response frame.

[0090] Figure 5 This is a diagram illustrating the CSMA / CA-based frame transmission operation that can be applied to this disclosure.

[0091] As mentioned above, in addition to physical carrier sensing of the medium directly sensed by the STA, the CSMA / CA mechanism also includes virtual carrier sensing. Virtual carrier sensing aims to compensate for problems such as hidden node issues that may occur during medium access. For virtual carrier sensing, the STA's MAC can use the Network Allocation Vector (NAV). The NAV is a value that indicates to other STAs the remaining time until the medium is available for current use or for STAs authorized to use the medium. Therefore, a value set to NAV corresponds to the period during which the STA sending the frame plans to use the medium, and during the corresponding period, STAs receiving the NAV value are prohibited from accessing the medium. For example, the NAV can be configured based on the value of the "Duration" field in the frame's MAC header.

[0092] exist Figure 5 In the example, it is assumed that STA1 intends to send data to STA2, and STA3 is in a position that can eavesdrop on some or all of the frames sent and received between STA1 and STA2.

[0093] To reduce the likelihood of transmission conflicts among multiple STAs in CSMA / CA-based frame transmission operations, a mechanism using RTS / CTS frames can be applied. Figure 5 In the example, when STA1 is transmitting, as a result of carrier sensing by STA3, it can be determined that the medium is in an idle state. That is, STA1 can correspond to a hidden node with respect to STA3. Alternatively, in Figure 5 In the example, it can be determined that while STA2 is transmitting, the carrier sensing result medium of STA3 is in an idle state. That is, STA2 can correspond to a hidden node with respect to STA3. By exchanging RTS / CTS frames before performing data transmission and reception between STA1 and STA2, STAs outside the transmission range of either STA1 or STA2, or STAs outside the carrier sensing range of transmissions from STA1 or STA3, can avoid attempting to occupy the channel during data transmission and reception between STA1 and STA2.

[0094] Specifically, STA1 can determine whether a channel is in use through carrier sensing. Regarding physical carrier sensing, STA1 can determine the channel occupancy / idle status based on the energy level or signal correlation detected in the channel. Alternatively, regarding virtual carrier sensing, STA1 can use a Network Allocation Vector (NAV) timer to determine the channel occupancy status.

[0095] When the channel is idle during DIFS, STA1 can send an RTS frame to STA2 after performing backoff. When STA2 receives the RTS frame, STA2 can send a CTS frame to STA1 after SIFS as a response to the RTS frame.

[0096] If STA3 cannot eavesdrop on CTS frames from STA2 but can eavesdrop on RTS frames from STA1, STA3 can use the duration information included in the RTS frame to set the NAV timer for the subsequent consecutive frame transmission period (e.g., SIFS+CTS frame+SIFS+data frame+SIFS+ACK frame). Alternatively, if STA3 can eavesdrop on CTS frames from STA2, STA3 can also use the duration information included in the CTS frame to set the NAV timer for the subsequent consecutive frame transmission period (e.g., SIFS+data frame+SIFS+ACK frame) even though STA3 cannot eavesdrop on RTS frames from STA1. That is, if STA3 can eavesdrop on one or more RTS frames or CTS frames from STA1 or STA2, STA3 can set the NAV accordingly. When STA3 receives a new frame before the NAV timer expires, STA3 can update the NAV timer using the duration information included in the new frame. STA3 does not attempt channel access until the NAV timer expires.

[0097] When STA1 receives a CTS frame from STA2, STA1 can send a data frame to STA2 after SIFS, starting from the time point when the CTS frame reception is complete. When STA2 successfully receives the data frame, STA2 can send an ACK frame to STA1 after SIFS as a response to the data frame. When the NAV timer expires, STA3 can determine whether the channel is in use through carrier sensing. If STA3 determines that the channel is not in use by other terminals during DIFS after the NAV timer expires, STA3 can attempt channel access after the contention window (CW) for random backoff has passed.

[0098] Figure 6 This is a diagram illustrating an example of a frame structure that can be used in a WLAN system to which this disclosure may be applied.

[0099] Using instructions or primitives (meaning a set of instructions or parameters) from the MAC layer, the PHY layer can prepare the MAC PDU (MPDU) to be transmitted. For example, when the PHY layer receives a command from the MAC layer requesting the start of transmission, it switches to transmit mode, configures the information (e.g., data) provided by the MAC layer in the form of a frame, and transmits it. Additionally, when the PHY layer detects a valid preamble in a received frame, it monitors the preamble header and sends a command to the MAC layer notifying the PHY layer of the start of reception.

[0100] In this way, information transmission / reception in a wireless LAN system is performed in the form of frames, and for this purpose, the PHY layer Protocol Data Unit (PPDU) format is defined.

[0101] A basic PPDU can include a Short Training Field (STF), a Long Training Field (LTF), a Signal (SIG) field, and a Data field. The most basic PPDU format (e.g., Figure 7 The non-HT (High Throughput) fields shown can consist solely of a Traditional-STF (L-STF), Traditional-LTF (L-LTF), Traditional-SIG (L-SIG) field, and a data field. Additionally, depending on the PPDU format type (e.g., HT mixed format PPDU, HT green format PPDU, VHT (Very High Throughput) PPDU, etc.), additional (or different types) RL-SIG, U-SIG, non-traditional SIG fields, non-traditional STF, non-traditional LTF (i.e., xx-SIG, xx-STF, xx-LTF (e.g., xx is HT, VHT, HE, EHT, etc.)) can be included between the L-SIG field and the data field.

[0102] STF is a signal used for signal detection, automatic gain control (AGC), diversity selection, precise time synchronization, etc., while LTF is a signal used for channel estimation and frequency error estimation. STF and LTF can be referred to as signals used for synchronization and channel estimation in the OFDM physical layer.

[0103] The SIG field can include various information related to PPDU transmission and reception. For example, the L-SIG field consists of 24 bits and can include 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 field. The RATE field can include information about the modulation and coding rate of the data. For example, the 12-bit length field can include information about the length or duration of the PPDU. For example, the value of the 12-bit length field can be determined based on the type of PPDU. For example, for non-HT, HT, VHT, or EHT PPDUs, the value of the length field can be determined to be a multiple of 3. For example, for HEPPDUs, the value of the length field can be determined to be a multiple of 3+1 or 3+2.

[0104] 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 can be used for synchronization of the descrambler at the receiver. 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 can be used to adjust the length of the data field by predetermined units.

[0105] MAC PDUs are defined according to various MAC frame formats, and a basic MAC frame consists of a MAC header, a frame body, and a Frame Check Sequence (FCS). MAC frames can be composed of MAC PDUs and transmitted / received via PSDUs in the data portion of the PPDU format.

[0106] The MAC header includes a frame control field, a duration / ID field, and an address field. The frame control field can include control information required for frame transmission / reception. The duration / ID field can be set to the time used to transmit the corresponding frame, etc. For details on the sequence control, QoS control, and HT control subfields of the MAC header, refer to the IEEE 802.11 standard document.

[0107] The Narrow Data PPDU (NDP) format refers to a PPDU format that does not include the data field. In other words, NDP is a frame format that includes the PPDU preamble of the general PPDU format (i.e., the L-STF, L-LTF, L-SIG fields and other non-traditional SIG, non-traditional STF, and non-traditional LTF (if present)) and does not include the remaining part (i.e., the data field).

[0108] Figure 7 This is a diagram illustrating an example of a PPDU as defined in the IEEE 802.11 standard of this disclosure.

[0109] 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 a data field. The basic PPDU format can also be referred to as a non-HT PPDU format (such as...). Figure 7 (as shown in (a)).

[0110] Compared to the basic PPDU format, the HT PPDU format (IEEE 802.11n) additionally includes the HT-SIG, HT-STF, and HT-LFT fields. Figure 7 The HT PPDU format shown in (b) can be referred to as the HT hybrid format. Furthermore, an HT green format PPDU can be defined, and this corresponds to a format consisting of HT-GF-STF, HT-LTF1, HT-SIG, one or more HT-LTFs and data fields, excluding L-STF, L-LTF, and L-SIG (not shown).

[0111] Compared to the basic PPDU format, examples of the VHT PPDU format (IEEE 802.11ac) additionally include VHTSIG-A, VHT-STF, VHT-LTF, and VHT-SIG-B fields (such as...). Figure 7 (as shown in (c)).

[0112] Compared to the basic PPDU format, examples of the HE PPDU format (IEEE 802.11ax) additionally include repeated L-SIG (RL-SIG), HE-SIG-A, HE-SIG-B, HE-STF, HE-LTF, and Packet Extension (PE) fields (such as...). Figure 7 (as shown in (d)). Some fields can be excluded, or their lengths can vary depending on the 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), but not in the HE PPDU format for single-user (SU). Furthermore, the HE-Trigger-Based (TB) PPDU format does not include HE-SIG-B, and the length of the HE-STF field can vary up to 8 μs. The Extended Range (HE ER) SU PPDU format does not include the HE-SIG-B field, and the length of the HE-SIG-A field can vary up to 16 μs. For example, RL-SIG can be configured to be the same as L-SIG. Based on the presence of RL-SIG, the receiving STA can determine whether the received PPDU is an HE PPDU or an EHT PPDU, which will be described later.

[0113] EHT PPDU format can include Figure 7 EHT MU (Multi-user) in (e) and Figure 7 The EHT TB (trigger-based) PPDU in (f). The EHT PPDU format is similar to the HE PPDU format in that it includes RL-SIG following L-SIG, but it can include U (generic)-SIG, EHT-SIG, EHT-STF and EHT-LTF following RL-SIG.

[0114] Figure 7 In (e), the EHT MU PPDU corresponds to a PPDU carrying one or more data (or PSDU) for one or more users. That is, the EHT MU PPDU can be used for both SU and MU transmissions. For example, the EHT MU PPDU can correspond to a PPDU for one or more receiving STAs.

[0115] Compared to EHT MU PPDU, Figure 7 In (f), the EHT-SIG is omitted from the EHT TB PPDU. The STA that receives the trigger for UL MU transmission (e.g., trigger frame or trigger response schedule (TRS)) can perform UL transmission based on the EHT TB PPDU format.

[0116] The L-STF, L-LTF, L-SIG, RL-SIG, U-SIG (general signal), and EHT-SIG fields can be encoded and modulated so that even conventional STAs can attempt demodulation and decoding, and can be mapped based on a determined subcarrier frequency interval (e.g., 312.5 kHz). These can be referred to as pre-EHT modulated fields. Next, the EHT-STF, EHT-LTF, data, and PE fields can be encoded and modulated to be demodulated and decoded by an STA that has successfully decoded a non-conventional SIG (e.g., U-SIG and / or EHT-SIG) and obtained the information contained in that field, and can be mapped based on a determined subcarrier frequency interval (e.g., 78.125 kHz). These can be referred to as EHT modulated fields.

[0117] Similarly, in the HE PPDU format, the L-STF, L-LTF, L-SIG, RL-SIG, HE-SIG-A, and HE-SIG-B fields can be referred to as pre-HE modulation fields, and the HE-STF, HE-LTF, data, and PE fields can be referred to as HE modulation fields. Additionally, in the VHT PPDU format, the L-STF, L-LTF, L-SIG, and VHT-SIG-A fields can be referred to as non-VHT modulation fields, and the VHT STF, VHT-LTF, VHT-SIG-B, and data fields can be referred to as VHT modulation fields.

[0118] Included Figure 7 In the EHT PPDU format, U-SIG can be configured based on, for example, two symbols (e.g., two consecutive OFDM symbols). Each symbol used for U-SIG (e.g., an OFDM symbol) can have a duration of 4 μs, and U-SIG can have a total duration of 8 μs. Each symbol of U-SIG can be used to transmit 26 bits of information. For example, each symbol of U-SIG can be transmitted and received based on 52 data tones and 4 pilot tones.

[0119] U-SIGs can be constructed in 20 MHz units. For example, if an 80 MHz PPDU is constructed, U-SIGs can be replicated. That is, the same four U-SIGs can be included in an 80 MHz PPDU. PPDUs with bandwidths exceeding 80 MHz can include different U-SIGs.

[0120] For example, A uncoded bits can be sent via U-SIG. The first symbol of U-SIG (e.g., U-SIG-1 symbol) can send the first X bits of the total A bits, and the second symbol of U-SIG (e.g., U-SIG-2 symbol) can send the remaining Y bits of the total A bits. The A bits (e.g., 52 uncoded bits) can include a CRC field (e.g., a 4-bit field) and a tail field (e.g., a 6-bit field). For example, the tail field can be used to terminate the lattice structure of the convolutional decoder and can be set to 0.

[0121] Bit information sent via U-SIG can be divided into version-independent bits and version-dependent bits. For example, U-SIG can be included in... Figure 7 The new PPDU format (e.g., UHR PPDU format) not shown in the figure, and can be included in the format of the U-SIG field included in the EHT PPDU format and the format of the U-SIG field included in the UHR PPDU format, the version-independent bits can be the same, and some or all of the version-related bits can be different.

[0122] For example, the size of the version-independent bits in U-SIG can be fixed or variable. Version-independent bits can be assigned only to the U-SIG-1 symbol, or to both the U-SIG-1 and U-SIG-2 symbols. Version-independent and version-dependent bits can be referred to by various names, such as first control bit and second control bit.

[0123] For example, the version-independent bits of U-SIG may include a 3-bit Physical Layer Version Identifier (PHY Version Identifier), which can indicate the PHY version (e.g., EHT, UHR, etc.) of the transmitted / received PPDU. The version-independent bits of U-SIG may include a 1-bit UL / DL Flag field. The first value of the 1-bit UL / DL Flag field is related to UL communication, and the second value is related to DL communication. The version-independent bits of U-SIG may include information about the length of the Transmission Opportunity (TXOP) and information about the BSS color ID.

[0124] For example, the version-related bits of U-SIG may include information that directly or indirectly indicates the type of PPDU (e.g., SU PPDU, MU PPDU, TB PPDU, etc.).

[0125] Information required for PPDU transmission and reception can be included in the U-SIG. For example, the U-SIG may also include information about bandwidth, information about the MCS technique applied to non-traditional SIGs (e.g., EHT-SIG or UHR-SIG), information indicating whether DCM (dual-carrier modulation) techniques (e.g., techniques used to achieve effects similar to frequency diversity by reusing the same signal on two subcarriers) are applied to non-traditional SIGs, information about the number of symbols used for non-traditional SIGs, and information about whether non-traditional SIGs are generated across the entire frequency band.

[0126] Some of the information required for PPDU transmission and reception may be included in U-SIG and / or non-traditional SIG (e.g., EHT-SIG or UHR-SIG). For example, information about the type of non-traditional LTF / STF (e.g., EHT-LTF / EHT-STF or UHR-LTF / UHR-STF), the length of the non-traditional LTF and the CP (cyclic prefix) length, the GI (guard interval) applicable to the non-traditional LTF, the preamble punching information applicable to the PPDU, and the resource unit (RU) allocation may be included only in U-SIG, only in non-traditional SIG, or may be indicated by a combination of information included in U-SIG and information included in non-traditional SIG.

[0127] Preamble puncturing can represent the transmission of a PPDU where no signal is present in one or more frequency units within the bandwidth of the PPDU. For example, the size of the frequency unit (or the resolution of the preamble puncturing) can be defined as 20 MHz, 40 MHz, etc. For example, preamble puncturing can be applied to PPDU bandwidths of a predetermined size or larger.

[0128] exist Figure 7 In the examples, non-traditional SIGs such as HE-SIG-B and EHT-SIG can include control information for receiving STAs. Non-traditional SIGs can be transmitted on at least one symbol, and a symbol can have a length of 4 μs. Information regarding the number of symbols used for EHT-SIGs can be included in previous SIGs (e.g., HE-SIG-A, U-SIG, etc.).

[0129] Non-traditional SIGs such as HE-SIG-B and EHT-SIG can include both public and user-specific fields. These public and user-specific fields can be encoded separately.

[0130] In some cases, the common field can be omitted. For example, in compressed mode using non-OFDMA (Orthogonal Frequency Division Multiple Access), the common field can be omitted, and multiple STAs can receive PPDUs (e.g., the data field of the PPDU) through the same frequency band. In uncompressed mode using OFDMA, multiple users can receive PPDUs (e.g., the data field of the PPDU) through different frequency bands.

[0131] The number of user-specific fields can be determined based on the number of users. A user block field can include up to two user fields. Each user field can be associated with either a MU-MIMO allocation or a non-MU-MIMO allocation.

[0132] The common fields may include CRC bits and a tail bit, where the length of the CRC bits can be determined to be 4 bits, and the length of the tail bit can be determined to be 6 bits and set to 000000. The common fields may include RU allocation information. RU allocation information may include information about the locations of RUs assigned to multiple users (i.e., multiple receiving STAs).

[0133] An RU can include multiple subcarriers (or tones). RUs can be used when transmitting signals to multiple STAs based on OFDMA technology. Additionally, RUs can be defined even when transmitting signals to a single STA. Resources can be allocated in units of RUs for non-traditional STFs, non-traditional LTFs, and data fields.

[0134] The appropriate RU size can be defined based on the PPDU bandwidth. RUs can be defined the same or different for the applied PPDU format (e.g., HEPPDU, EHT PPDU, UHR PPDU, etc.). For example, in the case of an 80 MHz PPDU, the RU layout for HEPPDU and EHT PPDU can be different. The appropriate RU size, number and location of RUs, DC (direct current) subcarrier locations and numbers, empty subcarrier locations and numbers, guard subcarrier locations and numbers, etc., for each PPDU bandwidth can be referred to as the tone scheme. For example, a tone scheme for high bandwidth can be defined as multiple iterations of a low-bandwidth tone scheme.

[0135] RUs of various sizes can be defined as 26-tone RUs, 52-tone RUs, 106-tone RUs, 242-tone RUs, 484-tone RUs, 996-tone RUs, and 2... 996 tone RU, 3 996-tone RU, etc. MRU (Multi-RU) differs from multiple individual RUs and corresponds to a group of subcarriers composed of multiple RUs. For example, an MRU can be defined as 52+26 tones, 106+26 tones, 484+242 tones, 996+484 tones, 996+484+242 tones, 2... 996+484 tones, 3 996 tones, or 3 996+484 tones. Furthermore, the multiple RUs constituting an MRU can be consecutive or non-consecutive in the frequency domain.

[0136] The specific size of the RU can be reduced or expanded. Therefore, the specific size of each RU in this disclosure (i.e., the number of corresponding tones) is not limiting but illustrative. In addition, in this disclosure, the number of RUs can vary depending on the RU size within a predetermined bandwidth (e.g., 20 MHz, 40 MHz, 80 MHz, 160 MHz, 320 MHz...).

[0137] Figure 7 The names of each field in the PPDU format are exemplary, and the scope of this disclosure is not limited to these names. Furthermore, the examples in this disclosure can be applied to… Figure 7 The PPDU format shown and based on Figure 7 A new PPDU format that excludes some fields and / or adds some fields, based on the PPDU format.

[0138] Figure 8 This is a diagram illustrating an exemplary format of the trigger frame to which the present disclosure may be applied.

[0139] A trigger frame can allocate resources for one or more TB PPDU transmissions and can request TB PPDU transmissions. The trigger frame may also include additional information required by the STA that sends the TB PPDU in response to the trigger frame. The trigger frame may include a public information field and a user information list field in the frame body.

[0140] The common information field may include information shared by one or more TB PPDU transmissions requested by the trigger frame, such as trigger type, UL length, presence of subsequent trigger frames (e.g., more TFs), presence of required channel sensing (CS), ULBW (bandwidth), etc. Figure 8 An example is shown of the EHT variant public information field format.

[0141] The 4-bit trigger type subfield can have values ​​from 0 to 15. Among these values, the values ​​0, 1, 2, 3, 4, 5, 6, and 7 of the trigger type subfield are defined to correspond to Basic, Beamforming Report Polling (BFRP), Multi-User Block Acknowledgment Request (MU-BAR), Multi-User Request Transmission (MU-RTS), Buffer Status Report Polling (BSRP), Multicast with Retry (GCR) MU-BAR, Bandwidth Query Report Polling (BQRP), and NDP Feedback Report Polling (NFRP), respectively, and values ​​8 to 15 are defined as reserved.

[0142] In public information, the trigger-related public information subfields may include information selectively included based on the trigger type.

[0143] The trigger frame may include a special user information field. This special user information field does not contain user-specific information, but rather extended public information not provided in the public information field.

[0144] The user information list contains zero or more user information fields. Figure 8 An example of the EHT variant user information field format is shown.

[0145] The AID12 subfield essentially indicates that it is a user information field for a STA with a corresponding AID. Furthermore, if the AID12 field has a predetermined specific value, it can be used for other purposes, such as assigning a Random Access (RA)-RU, or configuring it as a special user information field. A special user information field is a user information field that does not include user-specific information but includes extended public information not provided in the public information field. For example, a special user information field can be identified by the AID12 value 2007, and the special user information field flag subfield in the public information field can indicate whether a special user information field is included.

[0146] The RU allocation subfield can indicate the size and location of the RU / MRU. For this purpose, the RU allocation subfield can be interpreted together with the PS160 (primary / secondary 160MHz) subfield of the user information field, the UL BW subfield of the public information field, etc.

[0147] Triggering the TXOP sharing process for multiple peer-to-peer (P2P) communications

[0148] Triggering the TXOP sharing procedure allows an AP to allocate a portion of its TXOP to an associated non-AP STA for sending one or more non-TB PPDUs.

[0149] TXOP can correspond to the duration for which a specific QoS STA (e.g., AP STA and / or non-AP STA) is entitled to initiate a frame exchange sequence via the radio medium (WM). For example, TXOP can be defined by a start time and a maximum duration.

[0150] A frame can be called an MU-RTS TXOP Share (TXS) trigger frame when a TXOP share mode subfield associated with triggering the TXOP share mode is defined in the MU-RTS frame and the value of the subfield is not 0.

[0151] For example, the TXOP shared mode subfield can be encoded as follows.

[0152] If the value of the TXOP sharing mode subfield of the MU-RTS frame is 0, it corresponds to an MU-RTS that does not initiate the MU-RTS TXOP sharing process.

[0153] If the value of the TXOP sharing mode subfield of the MU-RTS frame is 1, it corresponds to the MU-RTS that initiated the MU-RTS TXOP sharing process. During the MU-RTS TXOP sharing process, the scheduled STA can send only the MPDU addressing its associated AP.

[0154] If the value of the TXOP sharing mode subfield of the MU-RTS frame is 2, it corresponds to the MU-RTS that initiates the MU-RTS TXOP sharing process, which enables the scheduled STA to send an MPDU addressing to its associated AP or to another STA.

[0155] The value 3 of the TXOP shared mode subfield in the MU-RTS frame can be defined as a reserved value.

[0156] Specifically, based on triggering TXOP sharing mode 1, the AP can send a MU-RTS TXS trigger frame to allocate time for the STA to send a non-TB PPDU to the AP, and the STA can respond to this.

[0157] According to Triggered TXOP Sharing Mode 2, the AP can send a MU-RTS TXS trigger frame to allocate time for STAs to send non-TB PPDUs to other STAs or the AP, and the STAs can respond to this. In Triggered TXOP Sharing Mode 2, the transmission from one STA to another can be called peer-to-peer (P2P) transmission.

[0158] A STA that uses information from the received MU-RTS TXS trigger frame as the latest basis for its Network Allocation Vector (NAV) update may not reset its NAV after the NAV timeout timer expires, unless it receives a CF-End frame that satisfies the conditions for TXOP truncation.

[0159] The NAV is maintained by each STA and is an indicator of the time period during which a STA will not initiate transmissions on the wireless medium (WM), regardless of whether the STA's Net Channel Assessment (CCA) function senses that the WM is busy. For example, the expected channel occupancy time can be indicated by the duration information in frames (e.g., RTS / CTS frames) exchanged between the transmitting and receiving STAs, and other STAs besides the transmitting and receiving STAs (e.g., third-party STAs) can set a NAV timer corresponding to the indicated time period and can refrain from transmitting on the WM until the NAV timer expires (or becomes 0).

[0160] After sending the CTS frame requested by the MU-RTS TXS trigger frame received from the AP associated with the STA, the STA can ignore the NAV set by the AP within the time allocation signaled in the MU-RTS TXS trigger frame. That is, if an NAV is set, the radio medium is considered busy or no transmission is initiated. Therefore, in order to allow transmission by STAs that have already been allocated / shared the AP's TXOP during the TXOP sharing trigger process, the STA can ignore the NAV set by the AP.

[0161] Figure 9 This is a diagram used to explain an example of how the TXOP sharing process can be triggered by applying this disclosure.

[0162] Figure 9 The example corresponds to the example of triggering TXOP sharing mode 2. That is, assuming the value of the TXOP sharing mode subfield of the MU-RTS TXS trigger frame sent by the AP to non-AP STA1 is set to 2.

[0163] Here, the MU-RTS TXS trigger frame sent by the AP to the non-AP STA1 may include time allocation information.

[0164] For example, the user information field format of the MU-RTS TXS trigger frame may include an AID12 subfield, an RU allocation subfield, an allocation duration subfield, a PS160 subfield, and reserved bits.

[0165] Here, the AID12 subfield corresponds to the STA's identification information, and the allocation duration subfield indicates the duration allocated to the corresponding STA. In this case, the corresponding duration can be indicated in units of 16µs. In this regard, for STA1 (i.e., a non-AP STA), the corresponding duration can be applied starting from the time the physical layer indication primitive (e.g., PHY-RXEND. indication primitive) for the PPDU that includes the MU-RTS TXS trigger frame is generated.

[0166] STA1 can send a CTS frame in response to a MU-RTS TXS trigger frame from the AP, and send data (i.e., P2P transmission) to STA2 and receive a block ACK during the time allocated by the MU-RTS TXS trigger frame (corresponding to a portion of the AP's TXOP). When the time allocated by the MU-RTS TXS trigger frame expires (e.g., after a PIFS from the expiration of the allocated time), the AP can perform a transmission (e.g., data transmission to another STA (STA3)) during its TXOP. Although Figure 15 As not shown, STA1 can also send frames to the AP during the time period allocated by the MU-RTS TXS trigger frame.

[0167] Regarding the above process, in existing wireless LAN systems, APs (e.g., EHT APs) can allocate time to only one STA for P2P transmission by using only one user information field in the MU-RTSTXS trigger frame.

[0168] However, to support P2P transmissions by multiple STAs, the aforementioned TXOP sharing triggering process needs to be modified. Therefore, this disclosure proposes a process (i.e., frame sequence and time allocation method) for supporting P2P transmissions by multiple STAs.

[0169] Figure 10 This is a diagram used to explain the operation of the STA during the triggering of TXOP sharing according to this disclosure.

[0170] In step S1010, the STA can receive trigger frames related to the sharing of TXOP from the AP.

[0171] For example, a STA can be a non-AP STA, a STA associated with an AP, or a STA within the coverage area of ​​the Basic Service Set (BSS) to which the AP belongs.

[0172] Here, the trigger frame may include a common information field and multiple user information fields for multiple STAs, including the corresponding STA.

[0173] For example, the trigger frame in step S1010 can be a trigger frame defined as allocating the duration associated with TXOP sharing to multiple STAs. That is, it is possible to define sending the trigger frame to multiple STAs.

[0174] In step S1020, the STA can send a response frame to the AP in response to the trigger frame.

[0175] For example, the trigger frame in step S1010 may correspond to a Multi-User Request to Send (MU-RTS) TXOP Share (TXS) trigger frame, and the response frame in step S1020 may correspond to a CTS (Complete Sending) frame for the MU-RTS TXS trigger frame.

[0176] In this regard, the timing of the duration allocated to the corresponding STA within the AP's TXOP can be identified based on the order of the user information fields for the corresponding STA among the multiple user information fields included in the trigger frame.

[0177] For example, if there are one or more user information fields for one or more other STAs included among a plurality of STAs before the user information field for the corresponding STA, the timing of the duration allocated to the corresponding STA can be located after the sum of the durations allocated to one or more other STAs. In this case, the corresponding STA can (sequentially) decode the one or more user information fields for one or more other STAs to obtain the sum of the one or more durations.

[0178] Furthermore, a STA can perform the transmission of frames addressed to another STA (e.g., P2P transmission) within the time allocated to it. In this case, the TXOP sharing mode subfield included in the common information field of the trigger frame can be set to a value (e.g., value 2) that indicates the TXOP sharing mode for allocating time to send frames addressed to another STA from that STA. For example, the TXOP sharing mode subfield included in the trigger frame can be set to a value indicating the TXOP sharing mode for allocating the time period for performing frame exchange between that STA and another STA.

[0179] Alternatively, the user information field for another STA included in a plurality of STAs may precede the user information field for the corresponding STA, and there may be a TXOP return from the other STA. Here, a TXOP return may refer to a procedure performed for the AP to terminate the time allocation when all transmissions are completed within the duration allocated to that STA. In this case, the STA may receive from the AP an additional frame that triggers the duration allocation within the TXOP. Here, this frame may correspond to at least one of a control frame (e.g., a MU-RTS TXS frame, an RTS frame, etc.), a Quality of Service (QoS) data frame, or a QoS empty frame.

[0180] Alternatively, the user information field for another STA included in the multiple STAs may precede the user information field for the corresponding STA, and there may be no other STA sending a response frame to the trigger frame. That is, it is possible that some STAs that have received the corresponding trigger frame may not send a response frame. In this case, the STA can receive an additional frame from the AP specifying the duration allocation within the trigger TXOP. Here, this frame may correspond to at least one of a control frame (e.g., MU-RTS TXS frame, RTS frame, etc.), a QoS data frame, or a QoS empty frame.

[0181] Alternatively, the user information field for another STA included in a plurality of STAs may precede the user information field for the corresponding STA, and to prevent conflicts, the AP may determine whether the channel is in an idle state at the end of the duration allocated to the other STA. If the channel is in an idle state, the STA can receive an additional frame from the AP, which triggers the allocation of duration within the TXOP based on the end time after the PIFS. Here, the frame may correspond to at least one of a control frame (e.g., MU-RTS TXS frame, RTS frame, etc.), a QoS data frame, or a QoS empty frame.

[0182] Additionally, various methods can be considered for signaling a TXOP sharing mode for allocating time to multiple STAs based on multiple user information fields included in the single trigger frame. For example, to indicate the TXOP sharing mode, the TXOP sharing mode subfield included in the public information field can be set to a value indicating the TXOP sharing mode for allocating time to multiple STAs based on multiple user information fields. Alternatively, regarding indicating the TXOP sharing mode, the public information field may include a specific 1-bit information for indicating the TXOP sharing mode for allocating time to multiple STAs based on multiple user information fields.

[0183] Subsequently, in step S1030, the STA (e.g., P2P TX STA) may perform frame exchange with another STA (e.g., P2P RX STA) within the time period allocated to the corresponding STA based on the aforementioned trigger frame.

[0184] At this point, the duration of frames sent in the time period allocated to the corresponding STA can be set based on the end timing of the aforementioned TXOP (i.e., the TXOP set by the AP) or the end timing of frame exchange with another STA.

[0185] For example, since the aforementioned duration is set based on the end timing of frame switching, this duration can be set from the end timing of the transmission of frames sent in the time period allocated to the corresponding STA to the end timing of frame switching.

[0186] In this regard, regarding the time period allocated to the corresponding STA, the duration of a frame sent by another STA can be set based on the duration of the frame sent by that STA.

[0187] Alternatively, within the TXOP, a first time period can be allocated for frame exchange between the first STA and the second STA, and after the first time period, a second time period can be allocated for frame exchange between the third STA and the fourth STA. In this case, the duration of the first frame transmitted in the first time period can be set from the end timing of the first frame transmission to the end timing of the frame exchange between the first STA and the second STA. Furthermore, the duration of the second frame transmitted in the second time period can be set from the end timing of the second frame transmission to the end timing of the frame exchange between the third STA and the fourth STA.

[0188] In another example, the duration mentioned above is set based on the end timing of the TXOP, which can be set from the end timing of the transmission of a frame sent in the time period allocated to the corresponding STA to the end timing of the TXOP.

[0189] In this regard, within the TXOP, a first time period can be allocated for frame exchange between the first STA and the second STA, and after the first time period, a second time period can be allocated for frame exchange between the third STA and the fourth STA. In this case, the first STA can correspond to the STA that receives the first frame from the AP that triggers the frame exchange with the second STA, and the third STA can correspond to the STA that receives the second frame from the AP that triggers the frame exchange with the fourth STA.

[0190] Here, the third STA can be configured to update the intra-BSS NAV based on frames sent from the first STA within the first time period to the NAV set based on the transmission address (TA) for the frames sent from the first STA.

[0191] Alternatively, the third STA may be configured to check / identify the TA for frames sent from the first STA based on frame exchanges between the first and second STAs.

[0192] Alternatively, if the Receive Address (RA) of a frame transmitted from the second STA is the same as the TA of a frame transmitted from the first STA, the third STA can be configured to set and ignore the basic NAV based on the frame transmitted from the second STA, or it can be configured not to set the basic NAV based on the frame transmitted from the second STA. In this case, the first STA and the third STA can be STAs within the coverage area of ​​the first BSS to which the AP belongs, and the second STA can be STAs within the coverage area of ​​a second BSS different from the first BSS.

[0193] Alternatively or additionally, the address information based on the second frame includes the MAC address of the first STA, and the second frame may be defined to also include information indicating whether the network allocation vector (NAV) should be reset.

[0194] Figure 10 The method described in the example, executed by STA, can be performed by Figure 1 The first device (100) is executed. For example, Figure 1 One or more processors (102) of the first device (100) may be configured to receive trigger frames associated with the sharing of TXOP from the AP (200) via one or more transceivers (106) and send response frames to the trigger frames to the AP (200).

[0195] Additionally, one or more processors (102) may be configured to identify the time point of the duration allocated to the first device (100) based on the order of the user information fields for the first device (100) among multiple user information fields included in the trigger frame. For example, if there are one or more user information fields for one or more other STAs before the user information fields for the first device (100), one or more processors (102) may be configured to decode the one or more user information fields for the one or more other STAs to calculate the sum of the durations allocated to the one or more other STAs. Based on this, one or more processors (102) may be configured to confirm that the time point of the duration allocated to the first device (100) is after the sum of the durations calculated based on the reception of the trigger frame.

[0196] Additionally, one or more processors (102) may be configured to send frames or non-TBPPDU transmissions addressed to another STA to the AP (200) via one or more transceivers (106) during a time period allocated for the first device (100) within the TXOP.

[0197] Furthermore, one or more memories (104) of the first device (100) may store information for execution by one or more processors (102) in order to perform the operation. Figure 10 The instructions for the methods described in the examples or examples described below.

[0198] Figure 11 This is a diagram used to explain the operation of the AP during the triggering of TXOP sharing according to this disclosure.

[0199] In step S1110, the AP can send trigger frames related to the sharing of TXOP to multiple STAs.

[0200] For example, multiple STAs can be non-AP STAs, or they can be STAs associated with an AP, or STAs within the coverage area of ​​the Basic Service Set (BSS) to which the AP belongs.

[0201] Here, the trigger frame may include a common information field and multiple user information fields for multiple STAs, including the corresponding STA.

[0202] For example, the trigger frame in step S1110 could be a trigger frame defined as allocating a duration associated with TXOP sharing to multiple STAs.

[0203] In this regard, the TXOP sharing mode subfield included in the aforementioned trigger frame can be set to a value indicating the TXOP sharing mode, which allocates a time period for performing frame exchange between STAs belonging to the plurality of STAs and STAs not belonging to the plurality of STAs.

[0204] In step S1120, the AP can receive a response frame to the trigger frame from one or more of the multiple STAs.

[0205] In this regard, the timing of the duration allocated to the corresponding STA within the AP's TXOP can be determined based on the order of the user information fields for the corresponding STA among the multiple user information fields included in the trigger frame.

[0206] In addition, when the above frame exchange (i.e., frame exchange between STAs belonging to multiple STAs and STAs not belonging to multiple STAs) is performed within the time period based on the trigger frame allocation in step S1110, the duration of the frames sent within the allocated time period can be set based on the end timing of TXOP or the end timing of frame exchange.

[0207] exist Figure 11 In the example, the features of trigger frames, response frames, TXOP sharing mode, and setting the duration of frames within the allocated time period (e.g., P2P operation duration) are similar to... Figure 10 The features described in the examples are the same, so redundant descriptions have been omitted.

[0208] Figure 11 The method described in the example, which is executed by the AP, can be performed by... Figure 1 The second device (200) is executed. For example, Figure 1 One or more processors (202) of the second device (200) can be configured to send a trigger frame related to the sharing of TXOP to a plurality of STAs (100) via one or more transceivers (206), and receive a response frame to the trigger frame from one or more of the plurality of STAs (100).

[0209] Additionally, one or more processors (202) can be configured to determine a point in time within the duration allocated to each STA (100) based on the order of the user information fields relative to multiple user information fields when generating a trigger frame. For example, one or more processors (202) can be configured to sequentially encode multiple user information fields for multiple STAs to generate a trigger frame.

[0210] Additionally, one or more memories (204) of the second device (200) may store information for execution by one or more processors (202) when the device is executed. Figure 11 The example or the command described in the example below.

[0211] In the following text, reference will be made to Figure 9 , Figure 10 and Figure 11 A more detailed example of this disclosure is described below.

[0212] In this disclosure, for clarity of explanation, STAs (e.g., STAs) are assigned for P2P transmission. Figure 9 Non-APSTA1 in the P2P TX STA is referred to as P2P TX STA, and from P2P TX STA (e.g., Figure 9In this context, a STA that receives frames (not AP STA2) is referred to as a P2P-RX STA. However, the scope of this disclosure is not limited to these names. Furthermore, in the following description, a STA not specified as non-AP or AP may correspond to an AP STA or a non-AP STA.

[0213] Implementation Method 1

[0214] This implementation relates to a method for allocating time to each STA to support P2P transmission of multiple STAs by using multiple user information fields corresponding to multiple STAs in a MU-RTS TXS trigger frame.

[0215] Specifically, to extend the triggering of the TXOP sharing process to multiple users, a method can be applied to allocate time by assigning a user information field to each of the multiple STAs via the MU-RTS TXS trigger frame. In this case, STAs that have already received the MU-RTS TXS trigger frame (i.e., its own user information field) can simultaneously send CTS frames.

[0216] At this point, the STA needs to know exactly when it is assigned to make non-TB PPDU transmissions or P2P transmissions to the AP.

[0217] The following describes a specific method for indicating the duration assigned to each STA based on the user information field.

[0218] As mentioned above, in order to allocate time to multiple STAs (i.e., multiple users), multiple user information fields can exist / include in the user information list field of the MU-RTS TXS trigger frame.

[0219] In this scenario, each user information field is defined as allocating time to each STA, and the time can be calculated sequentially from the first allocated user information field to the last. That is, the duration allocated to each STA can be indicated based on the order of the user information fields included in the user information list.

[0220] At this point, each STA can confirm / identify the start point of the duration assigned to it by adding the times of the user information fields located in front of / existing in its own user information field.

[0221] Figure 12 This is a diagram used to explain an example of triggering the TXOP sharing process according to the examples in this disclosure.

[0222] Reference Figure 12The AP can send MU-RTS TXS trigger frames with TXOP sharing mode set to 2 to multiple STAs (i.e., STA1, STA2, STA3) corresponding to the P2P TX STA. Figure 12 The AP in the text can correspond to an AP in an existing wireless LAN system (e.g., an EHT AP) or an AP in a next-generation wireless LAN system (e.g., a UHR AP, a next-generation Wi-Fi AP, etc.).

[0223] Here, the MU-RTS TXS trigger frame may include a common information field and a user information list field, and the user information list field may include multiple user information fields for multiple STAs.

[0224] Specifically, the user information list fields may include a first user information field (user information field #1) for allocating a T_1 duration to STA1, a second user information field (user information field #2) for allocating a T_2 duration to STA2, and a third user information field (user information field #3) for allocating a T_3 duration to STA3. Through these multiple user information fields, the AP can allocate a duration for non-TB PPDU transmissions or P2P transmissions to each STA.

[0225] At this time, multiple STAs (i.e., STA1, STA2, STA3) can simultaneously send CTS frames to the AP in response to the MU-RTS TXS trigger frame.

[0226] In the case of STA1, since its own user information field is placed first, STA1 can perform P2P transmission during the allocated T_1 duration after receiving the MU-RTS TXS trigger frame, as described above. Figure 9 The process is shown below.

[0227] STA2, which has been assigned a duration of T_2, can identify / recognize that the T_2 duration is the duration assigned to it, starting from the T_1 duration corresponding to the duration information assigned to STA1.

[0228] STA3, which has been assigned a duration of T_3, can identify / recognize that the duration of T_3 is the duration assigned to it after the sum of the durations of T_1 and T_2 (T_1+T_2), based on the duration of T_1 corresponding to the duration of STA1 and the duration of T_2 corresponding to the duration of STA2.

[0229] Figure 12 The method described in the paper has the advantage of low design complexity for multiple users (MUs).

[0230] Regarding this method, when each STA decodes the user information list field, it is necessary to decode the allocation duration subfield of the user information field other than its AID until it confirms that the user information field in which its AID is identified is the user information field.

[0231] Alternatively, with respect to this method, any STA may complete all transmissions before its allocated time expires, thus performing a TXOP return to the AP. In this case, the channel corresponding to a portion of the time allocated to the STA (i.e., the remaining time after all transmissions are completed) may not be operated by any STA.

[0232] Alternatively or concurrently, some STAs may respond to this method without regard to their channel state (e.g., sending a CTS frame to the AP). For example, if Figure 12 If STA2 does not respond to the CTS frame due to a busy channel, then the duration of T_2 can correspond to a period of inoperability. In other words, there may be situations where the channel corresponding to the durations of T_1 and T_3 is not operated by any STA.

[0233] Considering these points, to improve duration / channel utilization, another method can be applied whereby the AP notifies other STAs allocated durations of information about durations / channels not operated by other STAs. In this regard, the AP can send trigger frames to the corresponding STAs.

[0234] First, the method by which the AP sends a trigger frame to other STAs when a specific STA performs a TXOP return is described.

[0235] Figure 13 This is a diagram used to explain an example of triggering the TXOP sharing process according to another example of this disclosure.

[0236] Reference Figure 13 The AP can send MU-RTS TXS trigger frames with the TXOP sharing mode set to 2 to STA1 and STA2, which correspond to the P2P TX STA. Here, the MU-RTS TXS trigger frame may include a common information field and a user information list field, and the user list information field may include multiple user information fields for multiple STAs.

[0237] Specifically, the user information list fields may include a first user information field (user information field #1) for allocating a duration of T_1 to STA1 and a second user information field (user information field #2) for allocating a duration of T_2 to STA2. Through these multiple user information fields, the AP can allocate a duration for non-TB PPDU transmissions or P2P transmissions to each STA.

[0238] In this regard, STA1 and STA2 can simultaneously send CTS frames to the AP in response to the MU-RTS TXS trigger frame.

[0239] STA1 can perform P2P operations during the T_1 duration assigned to it.

[0240] If STA1 has no more frames to send during the T_1 duration, STA1 can perform a TXOP return to the AP to terminate the time allocated to it. For example, a TXOP return can be indicated by setting the RDG / More PPDU subfield of the HT Control header in the MAC header to a value of 0. QoS data / empty frames can also be used in this regard.

[0241] At this point, STA2 cannot recognize STA1's TXOP return because the T_2 duration has not yet begun and STA1 cannot recognize the TXOP return. Therefore, STA2 needs to wait until the T_2 duration begins.

[0242] With this in mind, in order to prevent channel waste during the duration before the start of the T_2 duration, the AP can send a frame to STA2 that triggers STA2 to perform P2P transmission during that duration.

[0243] Control frames or QoS data / empty frames can be used as trigger frames to trigger corresponding operations.

[0244] For example, as a control frame example, the MU-RTS TXS trigger frame can be (re)used. This method can be the same as the method for allocating time for a single user (SU). In this case, the information for the duration used for STA2 (i.e., the duration of T_2) can be changed to another time.

[0245] Since the trigger frame in the example corresponds to the MU-RTS TXS trigger frame that occurs in the middle of the TXOP, and the pre-allocated time is changed based on this, it can be used for Figure 13 The operation can be set to a separate mode. For example, for this operation, the reserved value of the existing TXOP shared mode field (i.e., 3) can be used, or the reserved bit of the common information field included in the MU-RTS TXS trigger frame can be used.

[0246] Alternatively or alternatively, due to... Figure 13The trigger frames related to the operation can be sent separately to STA2, so the allocation time information for STA2 can be sent in the A-Control field of the MAC header by utilizing QoS data / empty frames. That is, a new type of A-Control field can be defined. In this case, the corresponding type of A-Control field includes the allocation duration subfield as described above, and may also include an RU allocation subfield and / or a PS160 subfield, etc.

[0247] Alternatively or at another location, regarding Figure 13 The operation can be considered in the case where the RU location information (e.g., RU allocation subfield) or time allocation information (e.g., allocation duration subfield) remains unchanged. In this case, to reduce overhead, the AP can send an RTS frame corresponding to the QoS data / empty frame, along with a control frame, to STA2 without information such as the A-Control field mentioned above. At this time, the STA receiving the frame can recognize this and immediately start transmission because it has already allocated the RU and / or duration through the previous MU-RTS TXS trigger frame.

[0248] Next, we describe how the AP sends a trigger frame to another STA when a particular STA does not respond to a CTS frame.

[0249] Figure 14 This is a diagram used to explain an example of triggering the TXOP sharing process according to another example of this disclosure.

[0250] Reference Figure 14 The AP can send MU-RTS TXS trigger frames with the TXOP sharing mode set to 2 to multiple STAs (i.e., STA1, STA2, and STA3) corresponding to the P2P TX STA. Here, the MU-RTS TXS trigger frame may include a common information field and a user information list field, and the user list information field may include multiple user information fields for multiple STAs.

[0251] Specifically, the user information list fields may include a first user information field (user information field #1) for allocating a T_1 duration to STA1, a second user information field (user information field #2) for allocating a T_2 duration to STA2, and a third user information field (user information field #3) for allocating a T_3 duration to STA3. Through these multiple user information fields, the AP can allocate a duration for non-TB PPDU transmissions or P2P transmissions to each STA.

[0252] In this regard, STA1 and STA3 simultaneously send CTS frames to the AP in response to the MU-RTS TXS trigger frame, while STA2 may not send a CTS frame to the AP. In this case, since there is no CTS frame response from STA2, the channel may not be operational during the T_2 duration allocated to STA2.

[0253] Therefore, to prevent channel waste during the T_2 duration, the AP can send a frame to STA3, which triggers STA3 to perform P2P transmission during that duration.

[0254] Control frames or QoS data / empty frames can be used as trigger frames to trigger corresponding operations.

[0255] For example, as a control frame example, the MU-RTS TXS trigger frame can be (re)used. This method can be the same as the method for allocating time for a single user (SU). In this case, the information for the duration of STA3 (i.e., the duration of T_3) can be changed to another time.

[0256] Since the trigger frame in the example corresponds to the MU-RTS TXS trigger frame that occurs in the middle of the TXOP, and the pre-allocated time is changed based on this, it can be used for Figure 14 The operation can be set to a separate mode. For example, for this operation, the reserved value of the existing TXOP shared mode field (i.e., 3) can be used, or the reserved bit of the common information field included in the MU-RTS TXS trigger frame can be used.

[0257] Alternatively or alternatively, due to... Figure 14 The trigger frames related to the operation can be sent separately to STA3. Therefore, allocation time information for STA3 can be sent in the A-Control field of the MAC header by utilizing QoS data / empty frames. That is, a new type of A-Control field can be defined. In this case, the corresponding type of A-Control field includes the allocation duration subfield as described above, and may also include an RU allocation subfield and / or a PS160 subfield, etc.

[0258] Alternatively or at another location, regarding Figure 14The operation can be considered in the case where the RU location information (e.g., RU allocation subfield) or time allocation information (e.g., allocation duration subfield) remains unchanged. In this case, to reduce overhead, the AP can send an RTS frame corresponding to the QoS data / empty frame, along with a control frame, to STA3 without information such as the A-Control field mentioned above. At this time, the STA receiving the frame can recognize this and immediately start transmission because it has already allocated the RU and / or duration through the previous MU-RTS TXS trigger frame.

[0259] In addition, to prevent conflicts, a method is described for sending a trigger frame to another STA after the time allocated to one STA.

[0260] Figure 15 This is a diagram used to explain the triggering of the TXOP sharing process according to another example of this disclosure.

[0261] Reference Figure 15 The AP can send MU-RTS TXS trigger frames with the TXOP sharing mode set to 2 to STA1 and STA2, which correspond to the P2P TX STA. Here, the MU-RTS TXS trigger frame may include a common information field and a user information list field, and the user list information field may include multiple user information fields for multiple STAs.

[0262] Specifically, the user information list fields may include a first user information field (user information field #1) for allocating a duration of T_1 to STA1 and a second user information field (user information field #2) for allocating a duration of T_2 to STA2. Through these multiple user information fields, the AP can allocate a duration for non-TB PPDU transmissions or P2P transmissions to each STA.

[0263] In this regard, STA1 and STA2 can simultaneously send CTS frames to the AP in response to the MU-RTS TXS trigger frame.

[0264] STA1 can perform P2P operations during the T_1 duration assigned to it.

[0265] After STA1 completes the P2P operation, the AP can perform CCA during the PIFS period starting from the end of the time allocated to STA1 to avoid collisions. If the channel is in the IDLE state according to the CCA, the AP can send a trigger frame to STA2.

[0266] Once the STA2 has received the trigger frame, it sends a response frame to the AP and can perform a P2P operation (or send a non-TB PPDU to the AP) during the duration of T_2 based on the response time.

[0267] Here, the trigger frame can be a control frame or a QoS data / empty frame, similar to the above. Figure 13 and 14 Those in it.

[0268] For example, as a control frame example, the MU-RTS TXS trigger frame can be (re)used. This method can be the same as the method for allocating time for a single user (SU). In this case, the information for the duration used for STA2 (i.e., the duration of T_2) can be changed to another time.

[0269] Since the trigger frame in this example corresponds to the MU-RTS TXS trigger frame that occurs in the middle of the TXOP, and the pre-allocated time is changed accordingly, it can be used for... Figure 15 The operation can be set to a separate mode. For example, for this operation, the reserved value of the existing TXOP shared mode field (i.e., 3) can be used, or the reserved bit of the common information field included in the MU-RTS TXS trigger frame can be used.

[0270] Alternatively or alternatively, due to... Figure 15 The trigger frames related to the operation can be sent separately to STA2. Therefore, allocation time information for STA2 can be sent in the A-Control field of the MAC header by utilizing QoS data / empty frames. That is, a new type of A-Control field can be defined. In this case, the corresponding type of A-Control field includes the allocation duration subfield as described above, and may also include an RU allocation subfield and / or a PS160 subfield, etc.

[0271] Alternatively or at another location, regarding Figure 15 The operation can be considered in the case where the RU location information (e.g., RU allocation subfield) or time allocation information (e.g., allocation duration subfield) remains unchanged. In this case, to reduce overhead, the AP can send an RTS frame corresponding to the QoS data / empty frame, along with a control frame, to STA2 without information such as the A-Control field mentioned above. At this time, the STA receiving the frame can recognize this and immediately start transmission because it has already allocated the RU and / or duration through the previous MU-RTS TXS trigger frame.

[0272] The P2P transmission (or non-TBPPDU transmission to AP) method proposed in this embodiment for multiple users (e.g., multiple STAs) can be set to a specific mode.

[0273] In other words, the STA receiving the MU-RTS TXS trigger frame can detect / confirm the indication for the corresponding mode, thereby identifying that the corresponding MU-RTS TX trigger frame has been assigned to multiple users. Put another way, the STA receiving the corresponding MU-RTS TXS trigger frame can identify the presence of multiple user information fields and recognize that an operation may be occurring within the AP's TXOP (e.g., ...). Figure 13 / Figure 14 (Transmission of trigger frames in the process).

[0274] Signaling for this mode can be executed in the following manner.

[0275] For example, one could consider changing the meaning of values ​​1 and 2 of the TXOP shared mode subfield in the MU-RTS frame. That is, within the meaning of values ​​1 and 2 of the TXOP shared mode subfield in the aforementioned MU-RTS frame, mode signaling could be executed by extending / changing the operation for one STA to an operation for one or more STAs.

[0276] For another example, a mode used for P2P transmission to multiple STAs or non-TB PPDU transmission to an AP can be defined as a new TXOP sharing mode. That is, the value 3 of the TXOP sharing mode subfield in the aforementioned MU-RTS frame (i.e., the previously reserved value) can be used to signal this mode.

[0277] As another example, the common information field of the MU-RTS TXS trigger frame can be used to signal the mode for P2P transmission to multiple STAs or non-TB PPDU transmission to the AP. For this purpose, a reserved bit (e.g., value 1) of the common information field can be used.

[0278] Implementation Method 2

[0279] This implementation relates to a method for sequentially performing operations of sending MU-RTS TXS frames to each STA and receiving CST frames from the corresponding STA in order to support P2P transmission of multiple STAs.

[0280] Specifically, unlike the method in Implementation 1 where triggering is performed on multiple STAs at once, the AP can sequentially allocate duration to each STA using MU-RTS TXS trigger frames within a TXOP.

[0281] According to this method, when multiple STAs execute CTS responses simultaneously, the AP may not be unable to completely determine which STA executed the response. Furthermore, situations where a certain duration / channel allocated to a particular STA is not used may be avoided.

[0282] Figure 16 This is a diagram used to explain the triggering of the TXOP sharing process according to another example of this disclosure.

[0283] Reference Figure 16 The MU-RTS TXS trigger frame can be used to continuously allocate the duration for P2P operation for each STA.

[0284] In other words, when a P2P transmission is terminated within the allocated duration of each STA in a TXOP, the AP can allocate a duration for P2P transmission by sending a MU-RTS TXS trigger frame to the next STA.

[0285] For example, the AP can send a MU-RTS TXS trigger frame with the TXOP sharing mode set to 2 to STA1, which corresponds to the P2P TX STA. Here, the MU-RTS TXS trigger frame may include a common information field and a user information list field. The user information list field may include a first user information field (user information field #1) used to allocate the T_1 duration to STA1. STA1 can send a CTS frame to the AP in response to the MU-RTS TXS trigger frame and perform P2P operation during the T_1 duration.

[0286] When STA1's P2P operation terminates, the AP can send a MU-RTS TXS trigger frame with the TXOP sharing mode set to 2 to STA2, which corresponds to another P2P TX STA. Here, the MU-RTS TXS trigger frame may include a common information field and a user information list field. The user information list field may include a second user information field (user information field #2) used to allocate the T_2 duration to STA2. STA2 can send a CTS frame to the AP in response to the MU-RTS TXS trigger frame and perform P2P operation during the T_2 duration.

[0287] If, as Figure 13 As shown, if STA1 performs a TXOP return or does not perform a transmit / receive (TX / RS) operation during the operation duration, the AP can send a MU-RST TXS trigger frame for duration allocation to STA2.

[0288] Regarding the method described in this disclosure, the method proposed in Embodiment 1 has the effect of reducing the overhead for triggering frame signaling by being able to allocate durations to multiple STAs at once. Furthermore, even if some time intervals / channels are inoperable, the method proposed above (e.g., Figure 13 and Figure 14 The QoS data / empty frame / RTS frame transmission in the middle triggers the next STA to resolve the issue.

[0289] If this occurs frequently, a method can be applied to allocate the duration for P2P transmission by sending a MU-RTS TXS trigger frame individually to each STA using the method proposed in Implementation 2.

[0290] Implementation Method 3

[0291] This embodiment relates to a scheme for setting the duration of each frame in the P2P process within a shared TXOP in conjunction with the above-described TXOP sharing process.

[0292] In this regard, the duration setting can be related to the network allocation vector (NAV) set for the corresponding frame. Here, NAV can refer to reserved time information regarding the use of the wireless medium (e.g., delaying access to the wireless medium until NAV becomes 0).

[0293] In the case of a shared TXOP process, frame transmission for each STA is performed within the AP's TXOP. Therefore, a duration needs to be set for each frame, and for this purpose, one or more of the following methods can be used.

[0294] Implementation Method 3-1

[0295] Implementation 3-1 relates to a method for setting the duration of a frame to be sent by a STA (i.e., P2P TX) that has been allocated time from an AP for P2P operation as the TXOP end time of the AP.

[0296] Figure 17 An example of setting the duration of a frame based on a P2P operation according to an embodiment of the present disclosure is illustrated.

[0297] Reference Figure 17 In P2P operations, the duration of a frame sent can be set by the AP from the TX end time of the corresponding frame to the TXOP end time (t0).

[0298] By using the method proposed in this embodiment, channel access from another AP or another STA can be prevented within the AP's TXOP, where the NAV is set by the TXOP. In other words, this provides a highly efficient technical effect for protecting P2P operations of multiple STAs.

[0299] In this case, subsequent P2P operations are performed (e.g., Figure 17 A specific STA in STA 2's P2P operation may be affected by previous P2P operations (e.g., Figure 17 The impact of P2P operation on STA 1 in the middle.

[0300] For example, due to the P2P TX STA from the previous P2P operation (e.g., Figure 17 In the case of STA 1), the NAV in the BSS of the frame sent is not greater than the NAV in the BSS set from the AP, so the NAV does not need to be updated separately.

[0301] In this regard, when the P2P RX STA that previously performed a P2P operation is not in the same BSS (i.e., belongs to the OBSS), the basic NAV is set from the corresponding P2P RX STA, and therefore the STA that performs the subsequent P2P operation may not be able to send frames during the allocated time period.

[0302] Considering this scenario, NAV (i.e., the NAV within the aforementioned BSS) can be updated according to P2P TX STA (e.g., Figure 17 The sending address (TA) setting of STA 1 in the system.

[0303] Alternatively, the TA (i.e., the TA for frames sent from a P2P TX STA) may be identified and stored separately. For example, refer to Figure 17 In subsequent P2P operations, the STA can identify the P2P TX STA by listening to frames sent by the P2P TX STA and / or P2P RX STA in the previous P2P operation. Specifically, if the receive address (RA) of a frame sent from the P2P RX STA in the previous P2P operation is the same as the TA of the P2P TX STA (i.e., the TA for a frame sent from the P2P TX STA), the STA in the subsequent P2P operation can set and ignore the basic NAV, or can choose not to set the basic NAV.

[0304] Alternatively, when a P2P operation ends and the AP sends a trigger frame for subsequent P2P operations, the trigger frame may include information about NAV reset. That is, to address the aforementioned problem (e.g., the situation where frame transmission is impossible during the allocated interval because the P2P RX belonging to the OBSS has a basic NAV set), a method indicating NAV reset can be applied when the address information of the frame sent in the previous P2P operation includes the MAC address of the P2P TX STA. For example, the trigger frame may be defined to include information / fields indicating whether to reset the NAV and information / fields about the MAC address corresponding to the P2P TX STA.

[0305] Implementation Method 3-2

[0306] Implementation 3-2 relates to a method for setting the duration of frames to be sent by STAs (i.e., P2P TX STAs) that have been allocated time periods for P2P operation from APs as the end of the duration of frame exchange with P2P RX STAs.

[0307] Figure 18 Another example of setting the duration of a frame based on a P2P operation according to an embodiment of the present disclosure is illustrated.

[0308] Reference Figure 18 The duration of each frame in a P2P operation can be set to the end time of the duration from the transmission end time of the corresponding frame to the end time of the frame exchange between the P2P TX STA and the P2P RX STA (e.g., the end time of the corresponding P2P operation).

[0309] For example, in the P2P operation of STA 1, the duration of the transmitted frame can be set from the end timer of the corresponding frame transmission to the end timer of the corresponding P2P operation (t1). For example, in the P2P operation of STA 2, the duration of the transmitted frame can be set from the end timer of the corresponding frame transmission to the end timer of the corresponding P2P operation (t2).

[0310] In this regard, the P2P RX STA can set the duration of the frames to be sent by itself based on the duration set by the P2P TX STA.

[0311] Alternatively, the method proposed in this embodiment can also be applied to CTS frames / response frames sent by a STA performing a first P2P operation or a subsequent P2P operation including the first P2P operation.

[0312] The method proposed in this embodiment may prevent frames sent by P2P RX STA in previous P2P operations from affecting subsequent P2P operations.

[0313] The method proposed in this embodiment does not protect the entire TXOP of the AP. Therefore, in the event of a frame transmission failure between P2P operations or between the AP and the STA, a STA that has not configured NAV on the AP can access the channel and send frames.

[0314] In existing wireless LAN systems, the trigger frame for TXOP sharing (i.e., the MU-RTS TXS trigger frame) includes only one user information field. Therefore, duration allocation for P2P transmission or non-TB PPDU transmission is only possible for a single STA. In contrast, the method proposed in this disclosure can include one or more user information fields, i.e., multiple user message fields, in the MU-RTS TXS trigger frame. This approach offers a novel feature: the ability to allocate durations for P2P transmission or non-TB PPDU transmission for multiple STAs using a single MU-RTS TXS trigger frame. Therefore, multiple P2P transmissions can be supported within a single TXOP, and since time allocation can be performed for multiple STAs at once, signaling overhead is reduced and efficiency is improved, achieving new effects. Furthermore, based on the NAV setting method proposed in this disclosure, the technical effect of performing P2P transmission in a TXOP sharing mode triggered for multiple users / STAs can be achieved under any circumstances.

[0315] The above embodiments combine the elements and features of this disclosure in a predetermined form. Unless otherwise expressly stated, each element or feature should be considered optional. Each element or feature may be implemented without being combined with other elements or features. Furthermore, embodiments of this disclosure may include combinations of some elements and / or features. The order of operations described in embodiments of this disclosure may be changed. Some elements or features of one embodiment may be included in other embodiments, or may be replaced by corresponding elements or features of other embodiments. Obviously, embodiments may include claims that are not explicitly referenced in the claims, or may be included as new claims after the application has been amended.

[0316] It will be apparent to those skilled in the art that this disclosure may be implemented in other specific forms without departing from its essential characteristics. Therefore, the above detailed description should not be construed as restrictive in every respect, but rather as illustrative. The scope of this disclosure should be determined by a reasonable interpretation of the appended claims, and all variations within the equivalent scope of this disclosure are included within its scope.

[0317] The scope of this disclosure includes software or machine-executable commands (e.g., operating systems, applications, firmware, programs, etc.) that operate in a device or computer according to methods of various embodiments, as well as non-transitory computer-readable media that cause software or commands to be stored and executable in a device or computer. Commands that can be used to program a processing system to perform the features described in this disclosure can be stored in a storage medium or a computer-readable storage medium, and the features described in this disclosure can be implemented by using a computer program product including such a storage medium. 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 storage devices, and may include non-volatile memory, such as one or more disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid-state storage devices. The memory may optionally include one or more storage devices located remotely from the processor. The memory, or alternatively, the non-volatile memory devices in the memory include non-transitory computer-readable storage media. The features described in this disclosure can be stored in any machine-readable medium to control the hardware of a processing system and can be integrated into software and / or firmware that allows the processing system to interact with other mechanisms using the results of embodiments of this disclosure. Such software or firmware may include, but is not limited to, application code, device drivers, operating systems, and execution environments / containers.

[0318] Industrial applicability

[0319] The method presented in this disclosure is primarily described based on examples applied to IEEE 802.11-based systems (5G systems), but can be applied to systems other than those based on IEEE 802.11.

Claims

1. A method performed by a station (STA) in a wireless LAN system, the method comprising: receiving, from an access point (AP), a trigger frame related to sharing of a transmission opportunity (TXOP); transmitting, to the AP, a response frame for the trigger frame; and performing, with another STA, a frame exchange within a time period allocated to the STA based on the trigger frame, wherein a TXOP sharing mode subfield included in the trigger frame is set to a value indicating a TXOP sharing mode for allocating a time period for performing the frame exchange between the STA and the other STA, and wherein a duration of a frame transmitted in the time period allocated to the STA is set based on an end timing of the TXOP or an end timing of the frame exchange.

2. The method of claim 1, wherein, based on the duration being set according to the end timing of the frame exchange, the duration is set from a transmission end timing of the frame to the end timing of the frame exchange.

3. The method of claim 2, wherein, for the time period allocated to the STA, a duration of a frame transmitted by the other STA is set based on the duration of the frame transmitted by the STA.

4. The method of claim 1, wherein, based on, within the TXOP, a first time period being allocated for a frame exchange between a first STA and a second STA, and after the first time period, a second time period being allocated for a frame exchange between a third STA and a fourth STA, a duration of a first frame transmitted in the first time period is set from a transmission end timing of the first frame to an end timing of the frame exchange between the first STA and the second STA, and a duration of a second frame transmitted in the second time period is set from a transmission end timing of the second frame to an end timing of the frame exchange between the third STA and the fourth STA.

5. The method of claim 1, wherein, based on the duration being set according to the end timing of the TXOP, the duration is set from a transmission end timing of the frame to the end timing of the TXOP.

6. The method of claim 1, wherein, based on, within the TXOP, a first time period being allocated for a frame exchange between a first STA and a second STA, and after the first time period, a second time period being allocated for a frame exchange between a third STA and a fourth STA, the first STA corresponds to a STA that receives a first frame from the AP, the first frame triggering the frame exchange with the second STA, and the third STA corresponds to a STA that receives a second frame from the AP, the second frame triggering the frame exchange with the fourth STA.

7. The method of claim 6, wherein, the third STA is configured to update an intra-BSS NAV based on a frame transmitted from the first STA to be based on a transmit address, TA, set for the frame transmitted from the first STA during the first time period. 8.The method of claim 6, wherein, the third STA is configured to check a TA for a frame transmitted from the first STA based on the frame exchange between the first STA and the second STA. 9.The method of claim 6, wherein, a receive address, RA, based on a frame transmitted from the second STA is the same as the TA for a frame transmitted from the first STA, the third STA sets a basic NAV based on a frame transmitted from the second STA and ignores, or the third STA is configured to not set a basic NAV based on a frame transmitted from the second STA. 10.The method of claim 9, wherein, the first STA and the third STA are STAs within a coverage of a first BSS to which the AP belongs, and the second STA is a STA within a coverage of a second BSS different from the first BSS. 11.The method of claim 6, wherein, address information based on the second frame includes a MAC address of the first STA, the second frame further includes information indicating whether to reset a network allocation vector, NAV. 12.The method of claim 1, wherein, the trigger frame corresponds to a multi-user-request-to-send, MU-RTS, transmit opportunity, TXOP, sharing, TXS, trigger frame, and the response frame corresponds to an allow-to-send, CTS, frame for the MU-RTS TXS trigger frame. 13.The method of claim 12, wherein, the STA is an STA associated with the AP or an STA within a coverage of a BSS to which the AP belongs. 14.An apparatus for a station, STA, in a wireless local area network, WLAN, system, the apparatus comprising: at least one transceiver; and at least one processor connected to the at least one transceiver, wherein the at least one processor is configured to: receive, from an access point, AP, a trigger frame related to sharing of a transmission opportunity, TXOP; transmit, to the AP, a response frame for the trigger frame; and perform, based on the trigger frame, a frame exchange with another STA within a time period allocated to the STA, wherein a TXOP sharing mode subfield included in the trigger frame is set to a value indicating a TXOP sharing mode for allocating the time period for performing the frame exchange between the STA and the other STA, and wherein a duration of a frame transmitted in the time period allocated to the STA is set based on an end timing of the TXOP or an end timing of the frame exchange. 15.A processing unit configured to control a station, STA, in an online wireless local area network, WLAN, system, the processing unit comprising: at least one processor; and at least one computer memory operatively connected to the at least one processor and storing instructions for performing the method of any one of claims 1 to 13 based on execution by the at least one processor.

16. At least one non-transitory computer-readable medium storing at least one instruction, wherein, the at least one instruction, when executed by at least one processor, controls an apparatus in a wireless local area network (WLAN) system to perform the method of any one of claims 1 to 13.

17. A method performed by an access point (AP) in a wireless LAN system, the method comprising: receiving, from a plurality of stations (STAs), a trigger frame related to sharing of a transmission opportunity (TXOP); and receiving, from one or more of the plurality of STAs, a response frame to the trigger frame, wherein a TXOP sharing mode subfield included in the trigger frame is set to a value indicating a TXOP sharing mode for allocating a time period for performing a frame exchange between a STA belonging to the plurality of STAs and a STA not belonging to the plurality of STAs, and wherein, based on the frame exchange being performed in the time period allocated based on the trigger frame, a duration of a frame transmitted in the time period is set based on an end timing of the TXOP or an end timing of the frame exchange.

18. An apparatus for an access point (AP) in a wireless local area network (WLAN) system, the apparatus comprising: at least one transceiver; and at least one processor connected to the at least one transceiver, wherein the at least one processor is configured to: receive, from a plurality of stations (STAs), a trigger frame related to sharing of a transmission opportunity (TXOP); and receive, from one or more of the plurality of STAs, a response frame to the trigger frame, wherein a TXOP sharing mode subfield included in the trigger frame is set to a value indicating a TXOP sharing mode for allocating a time period for performing a frame exchange between a STA belonging to the plurality of STAs and a STA not belonging to the plurality of STAs, and wherein, based on the frame exchange being performed in the time period allocated based on the trigger frame, a duration of a frame transmitted in the time period is set based on an end timing of the TXOP or an end timing of the frame exchange.

Images