Method and apparatus for performing TID-to-link mapping based operation in wireless LAN system

Abstract

Disclosed are a method and an apparatus for operating in a wireless LAN system. According to one embodiment of the present disclosure, a method performed by means of a first STA MLD in a wireless LAN system comprises the steps of: transmitting a specific element including a multi-user (MU) enhanced distributed channel access (EDCA) mapping field to a second STA MLD, or receiving the specific element from the second STA MLD and performing an MU EDCA operation in at least one link on the basis of the specific element, wherein the MU EDCA mapping field can comprise: first information related to at least one link; and second information related to at least one traffic identifier (TID) corresponding to the at least one link.

Description

Technical Field

[0001] The present disclosure relates to communication operations in a wireless local area network (WLAN) system, and more particularly, to a method and apparatus for performing an operation based on TID (Traffic Identifier) ​​to link mapping in a next generation WLAN system. Background Art

[0002] New technologies have been introduced for wireless LAN (WLAN) to improve transmission rates, increase bandwidth, improve reliability, reduce errors, and reduce latency. Among WLAN technologies, the Institute of Electrical and Electronics Engineers (IEEE) 802.11 series of standards may be referred to as Wi-Fi. For example, technologies recently introduced to WLAN include enhancements to the Very High Throughput (VHT) standard of the 802.11ac standard and enhancements to High Efficiency (HE) of the IEEE 802.11ax standard.

[0003] In order to provide a more complete wireless communication environment, enhanced technologies for EHT (Extremely High Throughput) are being discussed. For example, technologies for supporting increased bandwidth, effective use of multiple bands, and increased spatial streams, multi-access point (AP) coordination and multiple-input multiple-output (MIMO) are being studied, and in particular, various technologies for supporting low-latency or real-time services are being studied. In addition, new technologies that support ultra-high reliability (UHR) by including improvements or extensions of EHT technology are being discussed. Summary of the invention

[0004] Technical issues

[0005] The technical problem of the present disclosure is to provide a method and apparatus for performing an operation based on TID-to-link mapping in a wireless LAN system.

[0006] The technical problem of the present disclosure is to provide a method and apparatus for applying MU (Multi-User) EDCA (Enhanced Distributed Channel Access) in a TID-to-link mapping process of a wireless LAN system to allocate delay-sensitive traffic to a specific link and assign priority for channel access to traffic classified as delay-sensitive traffic.

[0007] The technical objectives achieved by the present disclosure are not limited to the above-mentioned technical objectives, and other technical objectives not described herein will be clearly understood by those skilled in the relevant art from the following description.

[0008] Technical Solutions

[0009] According to one aspect of the present disclosure, a method performed by a first STA MLD in a wireless LAN system may include: sending a specific element including a multi-user (MU) enhanced distributed channel access (EDCA) map field to a second STA MLD or receiving a specific element from the second STA MLD; and performing a MU EDCA operation on at least one link based on the specific element, and the MU EDCA map field may include first information related to the at least one link and second information related to at least one traffic identifier (TID) corresponding to the at least one link.

[0010] According to one aspect of the present disclosure, a method performed by a second STA MLD in a wireless LAN system may include: generating a specific element including a multi-user (MU) enhanced distributed channel access (EDCA) map field; and transmitting the specific element including the MU EDCA map field to a first STA MLD, and the MU EDCA map field may include first information related to at least one link and second information related to at least one traffic identifier (TID) corresponding to the at least one link.

[0011] Technical Effects

[0012] According to various embodiments of the present disclosure, it is possible to provide a method and apparatus for performing an operation based on TID-to-link mapping in a wireless LAN system.

[0013] According to various embodiments of the present disclosure, a method and apparatus may be provided for applying MU EDCA in a TID-to-link mapping process of a wireless LAN system to allocate delay-sensitive traffic to a specific link and to allocate priority for channel access to traffic classified as delay-sensitive traffic.

[0014] According to various embodiments of the present disclosure, by creating a link for low-latency services / data through a new field during the TID-to-link mapping negotiation process, the priority of non-low-latency services can be reduced without modifying the existing TID-to-link mapping rules, so that the transmission and reception of low-latency services can be performed smoothly.

[0015] Effects achievable by the present disclosure are not limited to the above-described effects, and other effects not described herein may be clearly understood by those skilled in the art through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings, which are included as a part of the detailed description for understanding the present disclosure, provide embodiments of the present disclosure and describe technical features of the present disclosure through the detailed description.

[0017] Figure 1 A block configuration diagram of a wireless communication device according to an embodiment of the present disclosure is illustrated.

[0018] Figure 2 is a diagram illustrating an exemplary structure of a WLAN system to which the present disclosure can be applied.

[0019] Figure 3 is a diagram for describing a link setting process to which the present disclosure can be applied.

[0020] Figure 4 is a diagram for describing a backoff process to which the present disclosure can be applied.

[0021] Figure 5 is a diagram for describing a CSMA / CA-based frame transmission operation to which the present disclosure may be applied.

[0022] Figure 6 is a diagram for describing an example of a frame structure used in a WLAN system to which the present disclosure can be applied.

[0023] Figure 7 is a diagram illustrating an example of a PPDU defined in the IEEE 802.11 standard to which the present disclosure can be applied.

[0024] Figure 8 An exemplary format of a TID-to-link mapping element format and a TID-to-link control field format suitable for use with the present disclosure is illustrated.

[0025] Fig. 9 An exemplary structure of the EDCA parameter set field is shown.

[0026] Fig.10 is a diagram for describing an operation performed by a first STA MLD according to an embodiment of the present disclosure.

[0027] Fig.11 is a diagram for explaining an operation performed by the second STA MLD according to an embodiment of the present disclosure.

[0028] Fig.12 and Fig.13 An exemplary format of a TID-to-Link element including a MU EDCA mapping field according to an embodiment of the present disclosure is illustrated.

[0029] Fig.14 and Fig.15 An exemplary format of a TID-to-Link element including an LL MU EDCA parameter set element and a LL MU EDCA mapping field according to an embodiment of the present disclosure is illustrated.

[0030] Fig.16 and 17 FIG. 4 illustrates an exemplary format of an LL EDCA mapping element according to an embodiment of the present disclosure.

[0031] Fig.18 and 19 FIG. 2 illustrates an exemplary format of a TID-to-Link Mapping field indicating links and ACs to which MU EDCA is applied according to one embodiment of the present disclosure. DETAILED DESCRIPTION

[0032] Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description to be disclosed by the accompanying drawings is intended to describe exemplary embodiments of the present disclosure, rather than to represent the only embodiment in which the present disclosure can be implemented. The following detailed description includes specific details to provide a complete understanding of the present disclosure. However, those skilled in the relevant art will appreciate that the present disclosure can be implemented without these specific details.

[0033] In some cases, well-known structures and devices may be omitted, or may be shown in the form of a block diagram based on the core functions of each structure and device in order to prevent ambiguity in the concepts of the present disclosure.

[0034] In the present disclosure, when an element is referred to as being "connected", "combined" or "linked" to another element, it may include an indirect connection relationship between another element and a direct connection relationship. In addition, in the present disclosure, the term "comprising" or "having" specifies the presence of the mentioned features, steps, operations, components and / or elements, but does not exclude the presence or addition of one or more other features, stages, operations, components, elements and / or groups thereof.

[0035] In the present invention, terms such as "first", "second", etc. are only used to distinguish one element from another element and are not used to limit the elements, and unless otherwise specified, they do not limit the order or importance between the elements. Therefore, within the scope of the present disclosure, the first element in an embodiment may be referred to as the second element in another embodiment, and similarly, the second element in an embodiment may be referred to as the first element in another embodiment.

[0036] The terms used in this disclosure are intended to describe specific embodiments rather than to limit the claims. As used in the description of the 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" used in this disclosure may refer to one of the related enumerated items, or mean that it refers to and includes any and all possible combinations of two or more of them. In addition, unless otherwise stated, the " / " between words in this disclosure has the same meaning as "and / or".

[0037] Examples of the present disclosure may be applied to various wireless communication systems. For example, examples of the present disclosure may be applied to wireless LAN systems. For example, examples of the present disclosure may be applied to wireless LANs based on IEEE 802.11a / g / n / ac / ax standards. In addition, examples of the present disclosure may be applied to wireless LANs based on the newly proposed IEEE 802.11be (or EHT) standard. Examples of the present disclosure may be applied to wireless LANs based on the IEEE 802.11be version-2 standard corresponding to the additional enhanced technology of the IEEE 802.11be version-1 standard. In addition, examples of the present disclosure may be applied to next-generation standard-based wireless LANs after IEEE802.11be. In addition, examples of the present disclosure may be applied to cellular wireless communication systems. For example, it may be applied to cellular wireless communication systems based on technologies based on long term evolution (LTE) and technologies based on 5G new radio (NR) based on the third generation partnership project (3GPP) standard.

[0038] Hereinafter, technical features of examples to which the present disclosure can be applied will be described.

[0039] Figure 1 A block diagram of a wireless communication device according to an embodiment of the present disclosure is illustrated.

[0040] Figure 1 The first device 100 and the second device 200 illustrated in the figure may be replaced by various terms, such as terminal, wireless device, wireless transmit / receive 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 simple user, etc. In addition, the first device 100 and the second device 200 may include an access point (AP), a base station (BS), a fixed station, a node B, a base transceiver system (BTS), a network. It may be replaced by various terms such as an artificial intelligence (AI) system, a road side unit (RSU), a repeater, a router, a repeater and a gateway.

[0041] Figure 1 The devices 100 and 200 illustrated in FIG. 1 may be referred to as stations (STAs). For example, Figure 1The devices 100 and 200 illustrated in the figure may be referred to by various terms such as a transmitting device, a receiving device, a transmitting STA, and a receiving STA. For example, STA110 and 200 may perform an access point (AP) role or a non-AP role. That is, in the present disclosure, STA 110 and 200 may perform the functions of an AP and / or a non-AP. When STA 110 and 200 perform an AP function, they may be referred to as AP for short, and when STA 110 and 200 perform a non-AP function, they may be referred to as STA for short. In addition, in the present disclosure, an AP may also be indicated as an APSTA.

[0042] refer to Figure 1 , the first device 100 and the second device 200 can send and receive radio signals through various wireless LAN technologies (eg, IEEE802.11 series). The first device 100 and the second device 200 may include interfaces for a media access control (MAC) layer and a physical layer (PHY) conforming to the IEEE802.11 standard.

[0043] In addition, the first device 100 and the second device 200 may additionally support various communication standards (e.g., 3GPP LTE series, 5G NR series standards, etc.) technologies other than wireless LAN technology. In addition, the device of the present disclosure may be implemented in various devices, such as mobile phones, vehicles, personal computers, augmented reality (AR) devices, virtual reality (VR) devices, etc. In addition, the STA of the present specification may support various communication services, such as voice calls, video calls, data communications, autonomous driving, machine type communications (MTC), machine to machine (M2M), device to device (D2D), IoT (Internet of Things), etc.

[0044] The first device 100 may include one or more processors 102 and one or more memories 104, and may further include one or more transceivers 106 and / or one or more antennas 108. The processor 102 may control the memory 104 and / or the transceiver 106 and may be configured to implement the description, function, process, proposal, method and / or operation flow chart disclosed in the present disclosure. For example, the processor 102 may send a wireless signal including the first information / signal through the transceiver 106 after generating the first information / signal by processing the information in the memory 104. In addition, the processor 102 may receive a wireless signal including the second information / signal through the transceiver 106, and then store the information obtained by the signal processing of the second information / signal in the memory 104. The memory 104 may be connected to the processor 102 and may store various information related to the operation of the processor 102. For example, the memory 104 may store software code including instructions for executing all or part of the process controlled by the processor 102 or for executing the description, function, process, proposal, method and / or operation flow chart disclosed in the present disclosure. Here, the processor 102 and the memory 104 may be part of a communication modem / circuit / chip designed to implement wireless LAN technology (e.g., LTE 802.11 series). The transceiver 106 may be connected to the processor 102 and may send and / or receive wireless signals through one or more antennas 108. The transceiver 106 may include a transmitter and / or a receiver. The transceiver 106 may be used in conjunction with an RF (radio frequency) unit. In the present disclosure, a device may refer to a communication modem / circuit / chip.

[0045] The second device 200 may include one or more processors 202 and one or more memories 204, and may further include one or more transceivers 206 and / or one or more antennas 208. The processor 202 may control the memory 204 and / or the transceiver 206 and may be configured to implement the description, function, process, proposal, method and / or operation flow chart disclosed in the present disclosure. For example, the processor 202 may generate third information / signal by processing the information in the memory 204, and then send a wireless signal including the third information / signal through the transceiver 206. In addition, the processor 202 may receive a wireless signal including fourth information / signal through the transceiver 206, and then store the information obtained by signal processing of the fourth information / signal in the memory 204. The memory 204 may be connected to the processor 202 and may store various information related to the operation of the processor 202. For example, the memory 204 may store software code including instructions for executing all or part of the process controlled by the processor 202 or for executing the description, function, process, proposal, method and / or operation flow chart disclosed in the present disclosure. Here, the processor 202 and the memory 204 may be part of a communication modem / circuit / chip designed to implement wireless LAN technology (e.g., IEEE 802.11 series). The transceiver 206 may be connected to the processor 202 and may send and / or receive wireless signals through one or more antennas 208. The transceiver 206 may include a transmitter and / or a receiver. The transceiver 206 may be used in conjunction with an RF unit. In the present disclosure, a device may refer to a communication modem / circuit / chip.

[0046] In the following, the hardware elements of the device 100, 200 will be described in more detail. It is not limited thereto, but one or more protocol layers may be implemented by one or more processors 102, 202. For example, one or more processors 102, 202 may implement one or more layers (e.g., functional layers such as PHY, MAC). One or more processors 102, 202 may generate one or more PDUs (protocol data units) and / or one or more SDUs (service data units) according to the description, function, process, proposal, method, and / or operation flow chart disclosed in the present disclosure. One or more processors 102, 202 may generate messages, control information, data, or information according to the description, function, process, proposal, method, and / or operation flow chart disclosed in the present disclosure. One or more processors 102, 202 may generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the functions, processes, proposals, and / or methods disclosed in the present disclosure to provide them to one or more transceivers 106, 206. The one or more processors 102, 202 may receive signals (e.g., baseband signals) from the one or more transceivers 106, 206 and obtain PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, processes, proposals, methods, and / or operational flow charts disclosed in the present disclosure.

[0047] 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. In an 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, proposals, methods, and / or operational flowcharts included in the present 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, proposals, methods, and / or operational flowcharts included in the present 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, proposals, methods, and / or operational flowcharts included in the present disclosure may be implemented by firmware or software in the form of codes, commands, and / or command sets.

[0048] One or more memories 104, 204 may be connected to one or more processors 102, 202 and may store data, signals, messages, information, programs, codes, instructions, and / or commands in various forms. One or more memories 104, 204 may be configured with ROM, RAM, EPROM, flash memory, hard drive, registers, cache memory, computer-readable storage media, and / or combinations thereof. One or more memories 104, 204 may be located inside and / or outside one or more processors 102, 202. In addition, one or more memories 104, 204 may be connected to one or more processors 102, 202 via a variety of technologies such as wired or wireless connections.

[0049] One or more transceivers 106, 206 may send user data, control information, wireless signals / channels, etc. mentioned in the methods and / or operation flow charts, etc. of the present disclosure to one or more other devices. One or more transceivers 106, 206 may receive user data, control information, wireless signals / channels, etc. mentioned in the descriptions, functions, processes, proposals, methods, and / or operation flow charts, etc. included in the present disclosure from one or more other devices. For example, one or more transceivers 106, 206 may be connected to one or more processors 102, 202 and may send and receive wireless signals. For example, one or more processors 102, 202 may control one or more transceivers 106, 206 to send user data, control information, or wireless signals to one or more other devices. In addition, one or more processors 102, 202 may control one or more transceivers 106, 206 to receive user data, control information, or wireless signals from one or more other devices. In addition, 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 send and receive user data, control information, wireless signals / channels, etc. mentioned in the description, functions, processes, proposals, methods and / or operation flow charts, etc. included in the present disclosure through one or more antennas 108, 208. In the present invention, 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 to baseband signals by using one or more processors 102, 202 to process received user data, control information, wireless signals / channels, etc. One or more transceivers 106, 206 may convert user data, control information, wireless signals / channels, etc. processed by using one or more processors 102, 202 from baseband signals to RF band signals. Therefore, one or more transceivers 106, 206 may include (analog) oscillators and / or filters.

[0050] For example, one of the STAs 100 and 200 may perform the intended operation of an AP, and the other of the STAs 100 and 200 may perform the intended operation of a non-AP STA. Figure 1 The transceivers 106 and 206 of the present invention may perform transmission and reception operations of signals (e.g., packets or physical layer protocol data units (PPDUs) compliant with IEEE 802.11a / b / g / n / ac / ax / be). In addition, in the present disclosure, operations in which various STAs generate transmission / reception signals or perform data processing or calculation on transmission / reception signals in advance may be performed by Figure 1 The processors 102 and 202 are executed. For example, examples of operations of generating a transmit / receive signal or performing data processing or calculation on the transmit / receive signal in advance may include 1) determining / obtaining / configuring / calculating / decoding / encoding bit information of fields (signal (SIG), short training field (STF), long training field (LTF), data, etc.) included in the PPDU, 2) determining / configuring / obtaining time resources or frequency resources (e.g., subcarrier resources) used for fields (SIG, STF, LTF, data, etc.) included in the PPDU; 3) determining / configuring / obtaining a specific sequence (e.g., pilot sequence, STF / LTF sequence, additional sequence applied to SIG) for fields (SIG, STF, LTF, data, etc.) included in the PPDU action, 4) power control operations and / or power saving operations applied to STAs, 5) operations related to ACK signal determination / obtaining / configuring / calculating / decoding / encoding, etc. In addition, in the following examples, various information used by various STAs to determine / acquire / configure / calculate / decode / encode transmission and reception signals (e.g., information related to fields / subfields / control fields / parameters / power, etc.) may be stored in Figure 1 in the memories 104 and 204.

[0051] Hereinafter, downlink (DL) may mean a link for communication from an AP STA to a non-AP STA, and a DL PPDU / packet / signal may be transmitted and received through the DL. In DL communication, a transmitter may be a part of an AP STA, and a receiver may be a part of a non-AP STA. An uplink (UL) may mean a link for communication from a non-AP STA to an AP STA, and a UL PPDU / packet / signal may be transmitted and received through the UL. In UL communication, a transmitter may be a part of a non-AP STA, and a receiver may be a part of an AP STA.

[0052] Figure 2 is a diagram illustrating an exemplary structure of a wireless LAN system to which the present disclosure can be applied.

[0053] The structure of a wireless LAN system may consist of multiple components. A wireless LAN that supports STA mobility transparent to upper layers may be provided through the interaction of multiple components. A basic service set (BSS) corresponds to a basic building block of a wireless LAN. Figure 2 It is exemplarily shown that two BSSs (BSS1 and BSS2) exist and two STAs are included as members of each BSS (STA1 and STA2 are included in BSS1, and STA3 and STA4 are included in BSS2). Figure 2 The ellipse representing the BSS in FIG. 1 may also be understood to represent a coverage area in which the STAs included in the corresponding BSS maintain communication. This area may be referred to as a basic service area (BSA). When a STA moves out of a BSA, it cannot directly communicate with other STAs in the BSA.

[0054] If you don't consider Figure 2 , the most basic type of BSS in a wireless LAN is an independent BSS (IBSS), if the DS shown in is included. For example, an IBSS may have a minimal form containing only two STAs. For example, assuming that other components are omitted, BSS1 containing only STA1 and STA2 or BSS2 containing only STA3 and STA4 may correspond to representative examples of IBSSs, respectively. This configuration is possible when STAs can communicate directly without an AP. In addition, in this type of wireless LAN, it is not configured in advance but can be configured when a LAN is needed, and this may be referred to as a self-organizing network. Because the IBSS does not include an AP, there is no centralized management entity. That is, in the IBSS, STAs are managed in a distributed manner. In an IBSS, all STAs may be composed of mobile STAs, and access to a distributed system (DS) is not allowed, thereby forming a self-contained network.

[0055] The membership of a STA in a BSS can be changed dynamically by turning the STA on or off, entering or exiting a BSS region, etc. To become a member of a BSS, a STA can join the BSS using a synchronization process. In order to access all services of the BSS infrastructure, a STA should be associated with the BSS. This association can be established dynamically and can include the use of distributed system services (DSS).

[0056] The 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 some cases, communication between STAs at greater distances may be required. A distributed system (DS) can be configured to support extended coverage.

[0057] DS means a structure in which BSSs are interconnected. Specifically, Figure 2As shown in , the BSS can exist as an extended form of a network composed of multiple BSSs. DS is a logical concept and can be specified by the characteristics of the distributed system medium (DSM). In this regard, the wireless medium (WM) and the DSM can be logically separated. Each logical medium is used for a different purpose and is used by different components. These media are not limited to being the same or different. In this way, the flexibility of the wireless LAN structure (DS structure or other network structure) can be explained by the logical difference of multiple media. That is, the wireless LAN structure can be implemented in various ways, and the corresponding wireless LAN structure can be independently specified by the physical characteristics of each embodiment.

[0058] DS can support mobile devices by providing seamless integration of multiple BSSs and providing logical services necessary to address addresses to destinations. In addition, DS can further include a component called a portal, which serves as a bridge for connection between wireless LAN and other networks (e.g., IEEE 802.X).

[0059] The AP enables access to the DS through the WM for the associated non-AP STAs and means an entity that also has the functionality of a STA. Data movement between the BSS and the DS can be performed by the AP. For example, Figure 2 STA2 and STA3 shown in the figure have the functionality of STA and provide the function of allowing the associated non-AP STA (STA1 and STA4) to access the DS. In addition, because all APs basically correspond to STAs, all APs are addressable entities. The address used by the AP for communication on the WM and the address used by the AP for communication on the DSM are not necessarily the same. A BSS composed of an AP and one or more STAs can be called an infrastructure BSS.

[0060] Data sent from one of the STAs associated with an AP to the STA address of the corresponding AP can always be received on an uncontrolled port and can be processed by the IEEE 802.1X port access entity. In addition, when the controlled port is authenticated, the transmission data (or frame) can be delivered to the DS.

[0061] In addition to the above structure of DS, an extended service set (ESS) can also be configured to provide wide coverage.

[0062] ESS means a network in which a network of arbitrary size and complexity is composed of DS and BSS. ESS may correspond to a set of BSSs connected to one DS. However, ESS does not include DS. The ESS network is characterized by being regarded as an IBSS in the logical link control (LLC) layer. STAs included in the ESS can communicate with each other, and a mobile STA can move from one BSS to another BSS (within the same ESS) which is transparent to LLC. APs included in one ESS may have the same service set identifier (SSID). SSID is distinguished from BSSID, which is an identifier of BSS.

[0063] The wireless LAN system does not assume anything about the relative physical location of the BSS, and all of the following forms are possible. BSSs may partially overlap, which is a form commonly used to provide continuous coverage. In addition, the BSSs may not be physically connected, and logically, there is no limit to the distance between the BSSs. In addition, the BSSs may be physically located in the same location, which can be used to provide redundancy. In addition, one (or more) IBSSs or ESS networks may physically exist in the same space as one (or more) 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, this can be similar to the form corresponding to an ESS network.

[0064] Figure 3 is a diagram for explaining a link setting process to which the present disclosure can be applied.

[0065] In order for a STA to establish a link with respect to a network and send / receive data, it first discovers the network, performs authentication, establishes association, and needs to perform an authentication process for security. The link establishment process may also be referred to as a session initiation process or a session establishment process. In addition, the processes of discovery, authentication, association, and security settings of the link establishment process may be collectively referred to as an association process.

[0066] In step S310, the STA may perform a network discovery operation. The network discovery operation may include a scanning operation of the STA. That is, in order for the STA to access the network, it needs to find a network that 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.

[0067] Scanning schemes include active scanning and passive scanning. Figure 3The network discovery operation including the active scanning process is exemplarily illustrated. In active scanning, the STA performing the scan sends a probe request frame while moving the channel to find out which APs exist around it and wait for a response thereto. The responder sends a probe response frame to the STA that has sent the probe request frame as a response to the probe request frame. Here, the responder may be the STA that last sent a beacon frame in the BSS of the scanned channel. In the BSS, because the AP sends a beacon frame, the AP becomes the responder, and in the IBSS, the STAs in the IBSS take turns sending beacon frames, so the responder is not constant. For example, a 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 scanning in the same manner (i.e., transmission / reception of probe requests / responses on channel 2).

[0068] Although Figure 3 Although not shown in the figure, the scanning operation can be performed in a passive scanning manner. In passive scanning, the STA performing the scan waits for a beacon frame while moving the channel. The beacon frame is one of the management frames defined in IEEE 802.11, and is sent periodically to notify the existence of a wireless network and allow the STA performing the scan to find the wireless network and participate in the wireless network. In the BSS, the AP is used to send beacon frames periodically, and in the IBSS, the STAs within the IBSS take turns to send beacon frames. When the STA performing the scan receives the beacon frame, the STA stores the information for the BSS included in the beacon frame and records the beacon frame information in 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 scanning and passive scanning, active scanning has the advantages of less delay and lower power consumption than passive scanning.

[0069] After the STA discovers the network, an authentication process may be performed in step S320. In order to clearly distinguish it from the security setup operation of step S340 to be described later, this authentication process may be referred to as a first authentication process.

[0070] The authentication process includes a process in which the STA sends an authentication request frame to the AP, and in response thereto, the AP sends an authentication response frame to the STA. The authentication frame for authentication request / response corresponds to a management frame.

[0071] The authentication frame includes an authentication algorithm number, an authentication transaction sequence number, a status code, a challenge text, a robust security network (RSN), and a limited cycle group, etc. This corresponds to some examples of information that can be included in the authentication request / response frame, and can be replaced with other information or can further include additional information.

[0072] The STA may send an authentication request frame to the AP. The AP may determine whether to allow authentication of the corresponding STA based on the information included in the received authentication request frame. The AP may provide the result of the authentication process to the STA through an authentication response frame.

[0073] After the STA is successfully authenticated, an association process may be performed in step S330. The association process includes a process in which the STA sends an association request frame to the AP, and in response, the AP sends an association response frame to the STA.

[0074] For example, the association request frame may include information related to various capabilities, beacon listening interval, service set identifier (SSID), supported rates, supported channels, RSN, mobile domain, supported operation category, traffic indication map broadcast request (TIM broadcast request), interworking service capabilities, etc. For example, the association response frame may include information related to various capabilities, status code, association ID (AID), supported rates, enhanced distributed channel access (EDCA) parameter set, received channel power indicator (RCPI), received signal-to-noise ratio indicator (RSNI), mobile domain, timeout interval (e.g., association recovery time), overlapping BSS scanning parameters, TIM broadcast response, quality of service (QoS) map, etc. This corresponds to some examples of information that may be included in the association request / response frame, and may be replaced with other information, or may further include additional information.

[0075] After the STA successfully associates with the network, a security setup process may be performed in step S340. The security setup process of step S340 may be referred to as an authentication process through a robust security network association (RSNA) request / response, and the authentication process of step S320 may be referred to as a first authentication process, and the security setup process of step S340 may also be referred to simply as an authentication process.

[0076] The security setup process of step S340 may include, for example, a process of establishing a private key through a 4-way handshake of an Extensible Authentication Protocol over LAN (EAPOL) frame. In addition, the security setup process may be performed according to a security scheme not defined in the IEEE 802.11 standard.

[0077] Figure 4 is a diagram for explaining a backoff process to which the present disclosure can be applied.

[0078] In a wireless LAN system, the basic access mechanism of the medium access control (MAC) is the carrier sense multiple access with collision avoidance (CSMA / CA) mechanism. The CSMA / CA mechanism is also called the distributed coordination function (DCF) of the IEEE 802.11 MAC, and basically adopts a "listen before talk" access mechanism. According to this type of access mechanism, the AP and / or STA may perform a clear channel assessment (CCA) for sensing a wireless channel or medium within a predetermined time interval (e.g., a DCF interframe space (DIFS)) before starting transmission. As a result of the sensing, if it is determined that the medium is in an idle state, frame transmission is started through the corresponding medium. On the other hand, if it is detected that the medium is occupied or busy, the corresponding AP and / or STA does not start its own transmission, and a delay period (e.g., a random backoff period) for medium intervention may be set and frame transmission may be attempted after waiting. By applying a random backoff period, collisions can be minimized because several STAs are expected to attempt frame transmission after waiting for different time periods.

[0079] 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, and refers to a method in which all receiving APs and / or STAs periodically poll to receive data frames. In addition, HCF has enhanced distributed channel access (EDCA) and HCF-controlled channel access (HCCA). EDCA is a contention-based access method for a provider to provide data frames to multiple users, and HCCA uses a non-contention-based channel access method using a polling mechanism. In addition, HCF includes a media access mechanism for improving the QoS (Quality of Service) of a wireless LAN, and QoS data can be sent in both a contention period (CP) and a contention-free period (CFP).

[0080] refer to Figure 4 , the operation based on the random backoff period will be described. When an occupied / busy medium becomes idle, several STAs may attempt to send data (or frames). As a method for minimizing collisions, each STA may select a random backoff count respectively and attempt to transmit after waiting for the corresponding time slot time. The random backoff count has a pseudo-random integer value and may 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 CWmin as an initial value, but may take a value twice as large if a transmission failure occurs (for example, when an ACK for a transmitted frame is not received). When the CW parameter value reaches CWmax, data transmission may be attempted while maintaining the CWmax value until data transmission is successful, and when data transmission is successful, the CWmin value is reset. The values ​​of CW, CWmin, and CWmax are preferably set to 2n -1 (n = 0, 1, 2, ...).

[0081] When the random backoff process starts, the STA continuously monitors the medium while counting down the backoff slot according to the determined backoff count value. When it detects that the medium is occupied, it stops the countdown and waits, and when the medium becomes idle, it resumes the remaining countdown.

[0082] exist Figure 4 In the example of , when the packet to be sent arrives at the MAC of STA3, STA3 can send the frame immediately after confirming that the medium is idle for as much as DIFS. The remaining STAs monitor and wait for the medium to be occupied / busy. At the same time, data to be sent may also occur in each of STA1, STA2 and STA5, and when the medium is monitored as idle, each STA waits as long as DIFS, and then the backoff slot can be counted down according to the random backoff count value selected by each STA. Assume that STA2 selects the minimum backoff count value and STA1 selects the maximum backoff count value. That is, the case where the remaining backoff time of STA5 is less than the remaining backoff time of STA1 when STA2 completes the backoff count and starts frame transmission is illustrated. STA1 and STA5 temporarily stop the countdown and wait while STA2 occupies the medium. When STA2 occupancy ends and the medium becomes idle again, STA1 and STA5 wait for DIFS and resume the stopped backoff count. That is, after counting down the remaining backoff slot within the remaining backoff time, frame transmission can be started. Because the remaining backoff time of STA5 is less than that of STA1, STA5 starts frame transmission. While STA2 occupies the medium, data to be sent may also appear in STA4. From the perspective of STA4, when the medium becomes idle, STA4 can wait for DIFS, and then perform a countdown according to the random backoff count value selected by STA4 and start sending frames. Figure 4 The example shows a case where the remaining backoff time of STA5 coincides 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 case, STA4 and STA5 can double the CW value, select a random backoff count value, and perform a countdown. STA1 waits while the medium is occupied due to the transmission of STA4 and STA5, waits for DIFS when the medium becomes idle, and then starts frame transmission after the remaining backoff time has elapsed.

[0083] like Figure 4As shown in the example of , a data frame is a frame for transmitting data forwarded to a higher layer, and may be sent after performing a backoff after DIFS has elapsed from when the medium becomes idle. In addition, a management frame is a frame for exchanging management information that is not forwarded to a higher layer, and is sent after performing a backoff after an IFS such as DIFS or a point coordination function IFS (PIFS). As subtype frames of the management frame, there are beacons, association request / responses, reassociation request / responses, probe request / responses, authentication request / responses, and the like. A control frame is a frame for controlling access to a medium. As subtype frames of the control frame, there are request to send (RTS), clear to send (CTS), acknowledgement (ACK), power save poll (PS-Poll), block ACK (BlockAck), block ACK request (BlockACKReq), empty data packet announcement (NDP announcement), and triggers, and the like. If the control frame is not a response frame of a previous frame, it is sent after performing a backoff after DIFS has elapsed, and if it is a response frame of a previous frame, it is sent without performing a backoff after a short IFS (SIFS) has elapsed. The type and subtype of a frame can be identified by the type field and subtype field in the frame control (FC) field.

[0084] Quality of Service (QoS) STA can perform a backoff performed after the arbitration IFS (AIFS) of the access category (AC) to which the frame belongs, that is, AIFS [i] (where i is a value determined by AC), and then can transmit the frame. Here, the frame that can use AIFS [i] may be a data frame, a management frame, or a control frame other than a response frame.

[0085] Figure 5 is a diagram for explaining a CSMA / CA-based frame transmission operation to which the present disclosure can be applied.

[0086] As described above, the CSMA / CA mechanism includes virtual carrier sensing in addition to the physical carrier sensing in which the STA directly senses the medium. Virtual carrier sensing is intended to compensate for problems that may occur in media access, such as hidden node problems. For virtual carrier sensing, the STA's MAC can use a network allocation vector (NAV). NAV is a value that indicates to other STAs the remaining time until the medium is available for use by the STA that is currently using or has the right to use the medium. Therefore, the value set to NAV corresponds to the period in which the medium is scheduled for use by the STA that sends the frame, and the STA that receives the NAV value is prohibited from accessing the medium during the corresponding period. For example, the NAV can be configured based on the value of the "Duration" field of the MAC header of the frame.

[0087] exist Figure 5In the example of FIG. 1 , it is assumed that STA1 intends to send data to STA2, and STA3 is in a position to eavesdrop on some or all frames sent and received between STA1 and STA2.

[0088] In order to reduce the possibility of transmission conflicts between multiple STAs in CSMA / CA-based frame transmission operations, a mechanism using RTS / CTS frames can be applied. Figure 5 In the example of , while STA1's transmission is being performed, as a result of STA3's carrier sensing, it can be determined that the medium is in an idle state. That is, STA1 may correspond to a hidden node of STA3. Alternatively, Figure 5 In the example of , it can be determined that the carrier sensing result medium of STA3 is in an idle state while the transmission of STA2 is performed. That is, STA2 may correspond to a hidden node of STA3. By performing the exchange of RTS / CTS frames before data transmission and reception between STA1 and STA2, STAs outside the transmission range of one of STA1 or STA2, or STAs outside the carrier sensing range for transmission from STA1 or STA3 may not attempt to occupy the channel during data transmission and reception between STA1 and STA2.

[0089] Specifically, STA1 can determine whether the channel is in use through carrier sensing. In terms of physical carrier sensing, STA1 can determine the channel occupancy idle state based on the energy level or signal correlation detected in the channel. In addition, in terms of virtual carrier sensing, STA1 can use the network allocation vector (NAV) timer to determine the channel occupancy state.

[0090] When the channel is idle during DIFS, STA1 may send an RTS frame to STA2 after performing backoff. When STA2 receives the RTS frame, STA2 may send a CTS frame to STA1 after SIFS as a response to the RTS frame.

[0091] If STA3 cannot eavesdrop on the CTS frame from STA2 but can eavesdrop on the RTS frame from STA1, STA3 can set the NAV timer for the subsequent consecutively transmitted frame transmission period (e.g., SIFS+CTS frame+SIFS+data frame+SIFS+ACK frame) using the duration information included in the RTS frame. Alternatively, if STA3 can eavesdrop on the CTS frame from STA2, although STA3 cannot eavesdrop on the RTS frame from STA1, STA3 can set the NAV timer for the subsequent consecutively transmitted frame transmission period (e.g., SIFS+data frame+SIFS+ACK frame) using the duration information included in the CTS frame. That is, if STA3 can eavesdrop on one or more of the RTS or CTS frames from one or more of 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 before the NAV timer expires.

[0092] When STA1 receives a CTS frame from STA2, STA1 may send a data frame to STA2 after SIFS from the time point when reception of the CTS frame is completed. When STA2 successfully receives the data frame, STA2 may send an ACK frame to STA1 as a response to the data frame after SIFS. STA3 may determine whether the channel is being used by carrier sensing when the NAV timer expires. When STA3 determines that the channel is not being used by other terminals during DIFS after the NAV timer expires, STA3 may attempt channel access after a contention window (CW) according to random backoff has elapsed.

[0093] Figure 6 is a diagram for explaining an example of a frame structure used in a WLAN system to which the present disclosure can be applied.

[0094] With the help of 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 sent. For example, when receiving a command requesting the PHY layer to start transmission from the MAC layer, the PHY layer switches to the transmission mode and configures the information (e.g., data) provided from the MAC layer in the form of a frame and sends it. In addition, when the PHY layer detects a valid preamble of the received frame, the PHY layer monitors the header of the preamble and sends a command to the MAC layer notifying the PHY layer of the start of reception.

[0095] In this manner, information transmission / reception in the wireless LAN system is performed in the form of a frame, and for this purpose, a PHY layer protocol data unit (PPDU) frame format is defined.

[0096] The basic PPDU frame may include a short training field (STF), a long training field (LTF), a signal (SIG) field, and a data field. The most basic PPDU format (e.g., Figure 7 The non-HT (high throughput) shown in the PPDU format may consist of only the legacy STF (L-STF), the legacy LTF (L-LTF), the legacy SIG (L-SIG) field and the data field. In addition, depending on the type of PPDU format (e.g., HT mixed format PPDU, HT-greenfield format PPDU, VHT (very high throughput) PPDU, etc.), additional (or different types of) RL-SIG, U-SIG, non-legacy SIG field, non-legacy STF, non-legacy LTF (i.e., xx-SIG, xx-STF, xx-LTF (e.g., xx is HT, VHT, HE, EHT, etc.)), etc. may be included between the L-SIG field and the data field.

[0097] STF is a signal used for signal detection, automatic gain control (AGC), diversity selection, precise time synchronization, etc., and LTF is a signal used for channel estimation and frequency error estimation. STF and LTF may be referred to as signals for synchronization and channel estimation of the OFDM physical layer.

[0098] The SIG field may include various information related to PPDU transmission and reception. For example, the L-SIG field consists of 24 bits, and the L-SIG field may 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 may include information about the modulation and coding rate of the data. For example, the 12-bit length field may include information about the length or duration of the PPDU. For example, the value of the 12-bit length field may be determined based on the type of PPDU. For example, for non-HT, HT, VHT, or EHT PPDUs, the value of the length field may be determined as a multiple of 3. For example, for HE PPDUs, the value of the length field may be determined as a multiple of 3 + 1 or a multiple of 3 + 2.

[0099] The data field may include a SERVICE field, a physical layer service data unit (PSDU), and a PPDU TAIL bit, and may also include padding bits if necessary. Some bits of the SERVICE field may be used for synchronization of the descrambler at the receiving end. The PSDU corresponds to the MAC PDU defined in the MAC layer and may include data generated / used in the upper layer. The PPDU TAIL bit may be used to return the encoder to the 0 state. The padding bit may be used to adjust the length of the data field in predetermined units.

[0100] MAC PDU is 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). A MAC frame can be composed of a MAC PDU and transmitted / received through a PSDU of the data portion of a PPDU frame format.

[0101] The MAC header includes a frame control field, a duration / ID field, an address field, etc. The frame control field may include control information required for frame transmission / reception. The duration / ID field may be set to the time for transmitting the corresponding frame, etc. For detailed information on the sequence control, QoS control, and HT control subfields of the MAC header, please refer to the IEEE 802.11 standard document.

[0102] The Null Data PPDU (NDP) format refers to a PPDU format that does not include a data field. That is, NDP refers to a frame format that includes a PPDU preamble (i.e., L-STF, L-LTF, L-SIG fields and additional non-legacy SIG, non-legacy STF, non-legacy LTF (if present)) in a general PPDU frame format and does not include the remaining part (i.e., data field).

[0103] Figure 7 is a diagram illustrating an example of a PPDU defined in the IEEE 802.11 standard to which the present disclosure can be applied.

[0104] In standards such as IEEE 802.11a / g / n / ac / ax, various types of PPDUs have been used. The basic PPDU format (IEEE 802.11a / g) includes L-LTF, L-STF, L-SIG, and data fields. The basic PPDU format may also be referred to as non-HT PPDU format (such as Figure 7 (shown in (a)).

[0105] The HT PPDU format (IEEE 802.11n) includes HT-SIG, HT-STF, and HT-LFT fields in addition to the basic PPDU format. Figure 7 The HT PPDU format shown in (b) may be referred to as an HT-mixed format. In addition, an HT-greenfield format PPDU may be defined, and this corresponds to a format consisting of an HT-GF-STF, HT-LTF1, HT-SIG, one or more HT-LTFs, and a data field, excluding L-STF, L-LTF, and L-SIG (not shown).

[0106] An example of a VHT PPDU format (IEEE 802.11ac) includes VHT SIG-A, VHT-STF, VHT-LTF, and VHT-SIG-B fields in addition to the basic PPDU format (e.g. Figure 7 (shown in (c)).

[0107] An example of the HE PPDU format (IEEE 802.11ax) includes, in addition to the basic PPDU format, repeated L-SIG (RL-SIG), HE-SIG-A, HE-SIG-B, HE-STF, HE-LTF(s), a packet extension (PE) field (such as Figure 7 (d)). According to the detailed example of the HE PPDU format, some fields may be excluded or their lengths may vary. For example, the HE-SIG-B field is included in the HE PPDU format for multi-user (MU), and the HE-SIG-B field is not included in the HE PPDU format for single user (SU). In addition, the PPDU format based on the HE trigger (TB) does not include the HE-SIG-B, and the length of the HE-STF field may vary to 8us. 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 may vary to 16us. For example, the RL-SIG can be configured to be the same as the L-SIG. The receiving STA is able to know whether the received PPDU is a HE PPDU or an EHT PPDU based on the presence of the RL-SIG, which will be described later.

[0108] The EHT PPDU format may include Figure 7 (e) EHT MU (multi-user) and Figure 7 (f) EHT TB (trigger-based) PPDU. The EHT PPDU format is similar to the HE PPDU format in that it includes the RL-SIG followed by the L-SIG, but may include the U (Universal)-SIG, EHT-SIG, EHT-STF, and EHT-LTF following the RL-SIG.

[0109] Figure 7 The EHT MU PPDU in (e) corresponds to a PPDU that carries one or more data (or PSDU) for one or more users. That is, the EHT MU PPDU can be used for both SU transmission and MU transmission. For example, the EHT MU PPDU can correspond to a PPDU for one receiving STA or multiple receiving STAs.

[0110] Compared with EHT MU PPDU, Figure 7The EHT TB PPDU in (f) omits the EHT-SIG. A STA that receives a trigger (eg, a trigger frame or a trigger response schedule (TRS)) for UL MU transmission may perform UL transmission based on the EHT TB PPDU format.

[0111] The L-STF, L-LTF, L-SIG, RL-SIG, U-SIG (Universal Signal), EHT-SIG fields may be coded and modulated so that even legacy STAs may attempt to demodulate and decode, and may be mapped based on a determined subcarrier frequency interval (e.g., 312.5 kHz). These may be referred to as pre-EHT modulation fields. Next, the EHT-STF, EHT-LTF, Data, PE fields may be coded and modulated so that they may be demodulated and decoded by a STA that successfully decodes a non-legacy SIG (e.g., U-SIG and / or EHT-SIG) and obtains the information included in the field, and may be mapped based on a determined subcarrier frequency interval (e.g., 78.125 kHz). These may be referred to as EHT modulation fields.

[0112] Similarly, in the HE PPDU format, the L-STF, L-LTF, L-SIG, RL-SIG, HE-SIG-A, and HE-SIG-B fields may be referred to as pre-HE modulation fields, and the HE-STF, HE-LTF, Data, and PE fields may be referred to as HE modulation fields. In addition, in the VHT PPDU format, the L-STF, L-LTF, L-SIG, and VHT-SIG-A fields may be referred to as free VHT modulation fields, and the VHT STF, VHT-LTF, VHT-SIG-B, and data fields may be referred to as VHT modulation fields.

[0113] Figure 7 The U-SIG included in the EHT PPDU format may be configured based on, for example, two symbols (e.g., two consecutive OFDM symbols). Each symbol (e.g., OFDM symbol) used for the U-SIG may have a duration of 4us, and the U-SIG may have a total duration of 8us. Each symbol of the U-SIG may be used to transmit 26 bits of information. For example, each symbol of the U-SIG can be transmitted and received based on 52 data tones and 4 pilot tones.

[0114] U-SIG can be constructed in units of 20MHz. For example, if an 80MHz PPDU is constructed, the U-SIG may be repeated. That is, the 80MHz PPDU may include the same 4 U-SIGs. PPDUs with bandwidths exceeding 80MHz may include different U-SIGs.

[0115] For example, A uncoded bits may be sent via U-SIG, the first symbol of U-SIG (e.g., U-SIG-1 symbol) may send the first X bits of information out of the total A bits of information, and the second symbol of U-SIG (e.g., U-SIG-2 symbol) may send the remaining Y bits of information out of the total A bits of information. The A bits of information (e.g., 52 uncoded bits) may include a CRC field (e.g., a 4-bit long field) and a tail field (e.g., a 6-bit long field). For example, the tail field may be used to terminate a grid of a convolutional decoder and may be set to 0.

[0116] The bit information sent by U-SIG can be divided into version-independent bits and version-dependent bits. For example, U-SIG can be included in Figure 7 In a new PPDU format not shown in the EHT PPDU format (e.g., UHR PPDU format), and 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 may be the same, and some or all of the version-related bits may be different.

[0117] For example, the size of the version-independent bit of the U-SIG may be fixed or variable. The version-independent bit may be assigned only to the U-SIG-1 symbol, or to both the U-SIG-1 symbol and the U-SIG-2 symbol. The version-independent bit and the version-dependent bit may be referred to by various names, such as a first control bit and a second control bit.

[0118] For example, the version-independent bits of the U-SIG may include a 3-bit physical layer version identifier (PHY version identifier), and this information may indicate the PHY version of the transmitted / received PPDU (e.g., EHT, UHR, etc.). The version-independent bits of the U-SIG may include a 1-bit UL / DL flag field. The first value of the 1-bit UL / DL flag field is related to UL communication, and the second value of the UL / DL flag field is related to DL communication. The version-independent bits of the U-SIG may include information about the length of a transmission opportunity (TXOP) and information about a BSS color ID.

[0119] For example, the version-related bits of the U-SIG may include information directly or indirectly indicating the PPDU type (eg, SUPPDU, MU PPDU, TB PPDU, etc.).

[0120] Information necessary for PPDU transmission and reception may be included in the U-SIG. For example, the U-SIG may further include information about bandwidth, information about an MCS technology applied to a non-legacy SIG (e.g., EHT-SIG or UHR-SIG, etc.), information indicating whether a DCM (dual carrier modulation) technology (e.g., a technology that achieves an effect similar to frequency diversity by repeatedly using the same signal on two subcarriers) is applied to the non-legacy SIG, information about the number of symbols used for the non-legacy SIG, information about whether the non-legacy SIG is generated across the entire band, and the like.

[0121] Some information necessary for PPDU transmission and reception may be included in the U-SIG and / or the non-legacy SIG (e.g., EHT-SIG or UHR-SIG, etc.). For example, information about the type of non-legacy LTF / STF (e.g., EHT-LTF / EHT-STF or UHR-LTF / UHR-STF, etc.), information about the length of the non-legacy LTF and the CP (cyclic prefix) length, information about the GI (guard interval) applicable to the non-legacy LTF, information about preamble puncturing applicable to the PPDU, information about RU (resource unit) allocation, etc. may be included only in the U-SIG, only in the non-legacy SIG, or may be indicated by a combination of information included in the U-SIG and information included in the non-legacy SIG.

[0122] Preamble puncturing may mean transmission of a PPDU in which there is no signal 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) may be defined as 20 MHz, 40 MHz, etc. For example, preamble puncturing may be applied to a PPDU bandwidth of a predetermined size or greater.

[0123] exist Figure 7 In the example of , non-legacy SIGs such as HE-SIG-B and EHT-SIG may include control information for receiving STAs. Non-legacy SIGs may be transmitted on at least one symbol, and one symbol may have a length of 4us. Information on the number of symbols used for EHT-SIG may be included in a previous SIG (eg, HE-SIG-A, U-SIG, etc.).

[0124] Non-legacy SIGs such as HE-SIG-B and EHT-SIG may include common fields and user-specific fields. Common fields and user-specific fields may be compiled separately.

[0125] In some cases, the common field can be omitted. For example, in a compressed mode that does not apply OFDMA (Orthogonal Frequency Multiple Access), the common field can be omitted, and multiple STAs can receive PPDUs (e.g., data fields of PPDUs) through the same frequency band. In a non-compressed mode that applies OFDMA, multiple users can receive PPDUs (e.g., data fields of PPDUs) through different frequency bands.

[0126] The number of user-specific fields may be determined based on the number of users. A user block field may include up to two user fields. Each user field may be associated with a MU-MIMO allocation or may be associated with a non-MU-MIMO allocation.

[0127] The common field may include CRC bits and tail bits, and the length of the CRC bits may be determined to be 4 bits, and the length of the tail bits may be determined to be 6 bits and set to 000000. The common field may include RU allocation information. The RU allocation information may include information about the locations of RUs assigned to multiple users (ie, multiple receiving STAs).

[0128] RU can include multiple subcarriers (or tones). RU can be used when sending signals to multiple STAs based on OFDMA technology. In addition, RU can be defined even when sending signals to one STA. Resources can be allocated in units of RU for non-legacy STF, non-legacy LTF and data fields.

[0129] The applicable size of RU can be defined according to the PPDU bandwidth. For the applied PPDU format (e.g., HE PPDU, EHT PPDU, UHR PPDU, etc.), the RU can be defined the same or differently. For example, in the case of 80MHz PPDU, the RU placement of HEPPDU and EHT PPDU may be different. The applicable RU size, RU number and RU position, DC (direct current) subcarrier position and number, empty subcarrier position and number, protection subcarrier position and number, etc. for each PPDU bandwidth can be referred to as a tone plan. For example, a tone plan for high bandwidth can be defined in the form of multiple iterations of a low bandwidth tone plan.

[0130] RUs of various sizes may be defined as 26-tone RUs, 52-tone RUs, 106-tone RUs, 242-tone RUs, 484-tone RUs, 996-tone RUs, 2Х996-tone RUs, 3Х996-tone RUs, etc. MRUs (multiple RUs) are distinguished from multiple individual RUs and correspond to a group of subcarriers consisting of multiple RUs. For example, one MRU may be defined as 52+26 tones, 106+26 tones, 484+242 tones, 996+484 tones, 996+484+242 tones, 2Х996+484 tones, 3Х996 tones, or 3Х996+484 tones. In addition, the multiple RUs constituting one MRU may or may not be continuous in the frequency domain.

[0131] The specific size of the RU may be reduced or enlarged. Therefore, the specific size of each RU (i.e., the number of corresponding tones) in the present disclosure is not restrictive and is illustrative. In addition, in the present disclosure, within a predetermined bandwidth (e.g., 20, 40, 80, 160, 320 MHz, ...), the number of RUs may vary depending on the RU size.

[0132] Figure 7 The name of each field in the PPDU format is exemplary, and the scope of the present disclosure is not limited by the name. In addition, the examples of the present disclosure may be applied to Figure 7 The PPDU format shown in FIG. Figure 7 The PPDU format of the present invention excludes some fields and / or adds some fields to the new PPDU format.

[0133] TID to link mapping

[0134] In the following, TID to link mapping during Link Management (LM) is described. Here, TID means an identifier that can be used by upper layer entities to distinguish between MAC entities and MAC Service Data Units (MSDUs) supporting Quality of Service (QoS) within MAC data services.

[0135] For example, there may be 16 possible TID values. Eight of the 16 TID values ​​may identify a traffic class (TC), and the remaining eight may identify a parameterized traffic stream (TS). The TID may be assigned to an MSDU above the MAC layer.

[0136] The TID to link mapping mechanism refers to a mechanism that allows an AP MLD (Multi-Link Device) and a non-AP MLD that performs multi-link setup to determine how to map the setup links and TIDs in DL and UL.

[0137] Here, MLD means a device having one or more subordinate STAs as a logical entity and a single MAC data service and a single MAC service access point for logical link control (LLC).

[0138] A non-AP MLD is an MLD in which each STA belonging to the MLD is a non-AP STA. A multi-radio non-AP MLD is a non-AP MLD that supports receiving or exchanging frames on more than one link at a time. An AP MLD is an MLD in which each STA belonging to the MLD is an AP.

[0139] By default, all TIDs must be mapped to all configured links for both DL and UL. If two MLDs have explicitly negotiated TID-to-link mappings, each TID may be mapped to the same or a different set of links.

[0140] A provisioned link is defined as enabled if at least one TID is mapped to it, and may be defined as disabled if no TID is mapped to it. A TID should always be mapped to at least one provisioned link unless admission control is used. By default, a TID is mapped to all provisioned links, so all provisioned links may be enabled.

[0141] When a link is enabled, the link can be used for frame exchange, depending on the power state of the non-AP STA operating on the link. Only MSDUs or A-MSDUs with TIDs mapped to enabled links can be sent on the link. Management frames and control frames can only be sent on enabled links.

[0142] When a link is disabled, the link may not be used for frame exchanges, including management frames for both DL and UL.

[0143] During multi-link setup, the enablement / disablement of each link may be indicated by TID to link mapping. TID to link mapping may be performed in a default mapping mode or / and a negotiated mapping mode.

[0144] The default mapping mode refers to a mode in which all TIDs are mapped to links by the AP. Specifically, in the default mapping mode, all TIDs are mapped to all configured links for DL ​​and UL, and all configured links can be enabled. If TID-to-link mapping negotiation for other mappings has not occurred, has failed, or has been torn down, the AP MLD that has performed multi-link setup with a non-AP MLD can operate in the default mapping mode.

[0145] The negotiated mapping mode means a mode in which, when the STA transmits information about a link to be mapped to the TID to the AP through a TID-to-link mapping element included in a (re)association request frame or a TID-to-link mapping request frame, the AP accepts or rejects information about a link to be mapped to the TID.

[0146] Specifically, the MLD may support TID to link mapping negotiation. An MLD that supports TID to link mapping negotiation shall have "dot11TIDtoLinkMappingActivated" set to "true" and set the value of the TID to link mapping negotiation support subfield in the MLD Capabilities field of the base variant multilink element to a non-zero value. Otherwise, the MLD may set the value of the "TID to link mapping negotiation support" subfield to 0.

[0147] If the AP MLD indicates support for TID-to-link mapping negotiation in the multilink (re)setup procedure, the non-AP MLD may initiate TID-to-link mapping negotiation by including a TID-to-link mapping element in the (re)association request frame.

[0148] After receiving a (re)association request frame including a TID-to-link mapping element, the AP MLD may respond to the (re)association request frame according to the rules described below.

[0149] For example, the AP MLD may accept the TID-to-link mapping requested in the TID-to-link mapping element in the received (re)association request frame only if the AP MLD accepts the multilink (re)settings for all links for which mapping of at least one TID is requested. In this case, the AP MLD may not include the TID-to-link mapping element in the (re)association response frame.

[0150] Otherwise, the AP MLD may indicate the rejection of the proposed TID-to-link mapping by including a TID-to-link mapping element suggesting a preferred TID-to-link mapping in the (re)association response frame.

[0151] After a successful multilink (re)setup, in order to negotiate a new TID-to-link mapping, the initiating MLD with "dot11TIDtoLinkMappingActivated" equal to "true" can send an individually addressed TID-to-link mapping request frame to the responding MLD indicating its support for TID-to-link mapping negotiation.

[0152] After receiving an individually addressed TID-to-link mapping request frame, the responding MLD may send an individually addressed TID-to-link mapping response frame to the initiating MLD according to the rules described below.

[0153] For example, if the responding MLD receives the TID-to-link requested in the TID-to-link mapping element of the received TID-to-link mapping request frame, the responding MLD may set the status code to 0 (success) in the TID-to-link mapping response frame.

[0154] Otherwise, the responding MLD may indicate rejection of the proposed TID-to-link mapping by setting the status code to "DENIED_TID_TO_LINK_MAPPING" or "PREFERED_TID_TO_LINK_MAPPING_SUGGESTED" in the TID-to-link mapping response frame. The responding MLD may propose a preferred TID-to-link mapping by setting the status code to "PREFERRED_TID_TO_LINK_MAPPING_SUGGESTED" in the TID-to-link mapping response frame and including a TID-to-link mapping element in the TID-to-link mapping response frame.

[0155] When two MLDs have negotiated a TID-to-link mapping, each MLD may tear down the negotiated TID-to-link mapping by sending an individually addressed TID-to-link mapping teardown frame. After teardown, the MLDs may operate in a default mapping mode.

[0156] If the MLD has successfully negotiated with a peer MLD and / or for uplink and / or downlink TID-to-link mappings, where bit position i of the TID Link Mapping field of the TID To Link Mapping element is set to 0, then TID n may not be mapped to the link associated with Link ID i in the uplink and / or downlink.

[0157] If the MLD has successfully negotiated with a peer MLD and / or for uplink and / or downlink TID-to-link mapping, where bit position i of the TID Link Mapping field of the TID To Link Mapping element is set to 1, then TID n may be mapped to the link associated with link ID i in the uplink and / or downlink.

[0158] Figure 8 The illustration may be applied to a TID-to-link mapping element format and a TID-to-link control field format of the present disclosure.

[0159] The TID-to-link mapping element indicates the links through which frames belonging to each TID can be exchanged. Figure 8 As illustrated in , a TID-to-link mapping element may include an element ID subfield, a length subfield, an element ID extension subfield, a TID-to-link mapping control subfield, and a link mapping subfield for TID n (where n is an integer greater than or equal to 0).

[0160] In addition, the TID-to-link mapping control subfield may include a direction subfield, a default link mapping subfield, a reserved subfield, and a link mapping presence indicator subfield.

[0161] If the TID to Link Mapping element provides TID to Link Mapping information for a frame transmitted in a downlink, the Direction subfield value may be set to 0 (uplink). If the TID to Link Mapping element provides TID to Link Mapping information for a frame transmitted in an uplink, the Direction subfield value may be set to 1 (downlink). If the TID to Link Mapping element provides TID to Link Mapping information for a frame transmitted in a downlink and an uplink, the Direction subfield value may be set to 2 (bidirectional link). In the case of 3 among the Direction subfield values, it may be reserved.

[0162] And, if the TID-to-link mapping element indicates a default TID-to-link mapping, the default link mapping subfield value may be set to 1. Otherwise, the default link mapping subfield value may be set to 0.

[0163] The Link Map Presence Indicator subfield may indicate whether a Link Map field for TID n is present on the TID to Link Map element. A value of 1 at bit position n of the Link Map Presence Indicator subfield may indicate that a Link Map field for TID n is present on the TID to Link Map element. A value of 0 at bit position n of the Link Map Presence Indicator subfield may indicate that a Link Map field for TID n is not present on the TID to Link Map element. When the Default Link Map subfield value is set to 1, the Link Map Presence Indicator subfield may be retained.

[0164] The Link Mapping field for TID n may indicate a link on which frames belonging to TID n may be sent. A value of 1 at bit position i of the Link Mapping field for TID n may indicate that TID n is mapped to a link associated with Link ID i for the direction specified in the Direction subfield. If the Default Link Mapping subfield value is set to 1, the Link Mapping field for TID n may not be present.

[0165] EDCA Operation Using MU EDCA Parameters

[0166] Fig. 9 (a) illustrates the MU EDCA parameter set element format. The QoS information field included in the MU EDCA parameter set element may include an EDCA parameter set update count subfield. The EDCA parameter set update count subfield may indicate when the EDCA parameters and (in the case of HE BSS) the MU EDCA parameters have changed.

[0167] The formats of the MU AC_BE, MU AC_BK, MU AC_VI, and MU AC_VO parameter record fields may be the same. The format of the ACI / AIFSN field may be defined as follows: Fig. 9 Here, a value of 0 in the AIFSN field may indicate that EDCA is disabled for a time period specified by the MU EDCA timer for the corresponding AC.

[0168] The value of the AC index (ACI) may refer to the AC to which all parameters of the corresponding record correspond. The mapping relationship between the ACI and the AC may be defined as shown in Table 1.

[0169]

Table 1

[0170]

[0171] The ACM (Admission Control Required) subfield may indicate that admission control is required for the AC. If the ACM subfield value is set to 0, there may be no admission control for the AC. If the ACM subfield value is set to 1, admission control must be used before transmission using the access parameters specified for the AC. The AIFSN subfield may indicate the number of slots after SIFS that the STA delays before invoking backoff or starting transmission. The minimum value of the AIFSN subfield may be 2.

[0172] The format of the ECWin / ECWmax field can be as follows Fig. 9 The ECWmin and ECWmax subfields can be used to represent CWmin (i.e., 2 ECWmin -1) and CWmax (i.e., 2 ECWmax -1) value.

[0173] The MU EDCA Timer field may indicate the duration (in units of 8 TUs) of time that the HE STA will use the MU EDCA parameters for this AC, excluding the reserved value.

[0174] The HE AP may set the QoS Information field of the MU EDCA parameter set element to the same value as the QoS Information field of the EDCA parameter set element. The HE AP may change the MU EDCA parameters by including a MU EDCA parameter set element with updated MU EDCA parameters in the beacon frames and probe response frames it transmits. The EDCA parameter set update count subfield in the EDCA parameter set element and the QoS Information field of the MU EDCA parameter set element may be incremented whenever an EDCA parameter or a MU EDCA parameter is changed.

[0175] A non-AP HE STA may update the "dot11EDCATable" and "dot11MUEDCATable" fields corresponding to the EDCA parameter set element or MU EDCA parameter set element within a time interval equal to one beacon interval after receiving an updated EDCA or MU EDCA parameter set from the associated AP. When a HE STA updates its MIB attributes, it may store the value of the EDCA parameter set update count subfield in the QoS information field of the received EDCA parameter set element or MU EDCA parameter set element.

[0176] A non-AP HE STA can use the EDCA Parameter Set Update Count subfield in the QoS Capability element of the beacon frame to determine whether the STA is currently using EDCA (and optionally MU EDCA) parameter values. If the EDCA Parameter Set Update Count subfield value is different from the stored value, the STA can query the AP for updated EDCA (and optionally any MU EDCA) parameter values ​​by sending a Probe Request frame.

[0177] If the beacon frame has a QoS capability element, the EDCA parameter set element and the MU EDCA parameter set element may not be present. Here, the HE STA may send a probe request frame to the AP to obtain updated parameters. A non-AP HE STA that receives a basic trigger frame including a user information field for STA may update its CWmin [AC], CWmax [AC], AIFSN [AC], and MUEDCATimer [AC] state variables to the values ​​included in "dot11MUEDCATable".

[0178] If the STA receives an immediate ACK for the frame or the QoS data frame does not require immediate ACK, the STA can successfully send the QoS data frame to the AC in the HE TB PPDU.

[0179] The MUEDCATimer[AC] state variable may be updated with the value included in the MU EDCA timer subfield of the MU EDCA parameter set element. The backoff counter maintenance corresponding to the updated state variable may follow the rules, except that if AIFSN[AC] is 0, the EDCAF corresponding to that AC shall be suspended until MUEDCATimer[AC] reaches 0 or is reset to 0.

[0180] If the transmitted HE TB PPDU includes one or more QoS data frames for this AC that requires immediate acknowledgement, the updated MUEDCATimer[AC] shall start at the end of the immediate response, or if the transmitted HE TB PPDU is transmitted, it may start at the end of the HE TB PPDU. The HE TB PPDU may not include any QoS data frames for this AC that requires immediate acknowledgement.

[0181] In non-AP HE STA, when the value of each MUEDCATimer[AC] is non-zero, each MUEDCATimer[AC] can count down to 0 evenly without hanging.

[0182] A non-AP STA that transmits a frame for the AP having the OM Control subfield, having a value of the UL MU Disable subfield set to 1, or having a value of the UL MU Disable subfield set to 0 and a value of the UL MU Data Disable subfield set to 1 may not participate in the UL MU operation. Therefore, it may not update the EDCA access parameters to the values ​​included in the MU EDCA parameter set element.

[0183] A non-AP STA may not update its state variables to the values ​​included in the MU EDCA parameter set element if any of the following applies:

[0184] a) If the trigger frame to the STA is not a basic trigger frame;

[0185] b) if the STA does not include a QoS data frame in the HE TB PPDU response sent in response to the Basic Trigger Frame;

[0186] c) If the STA sends a HE TB PPDU in response to a basic trigger frame according to predefined rules.

[0187] A non-AP STA that sends an unaddressed frame to an associated AP may use EDCA parameter values ​​included in the most recently received EDCA parameter set element sent by the STA's associated AP, or default EDCA parameter values.

[0188] When the MUEDCATimer[AC] of a non-AP HE STA reaches 0 due to countdown or reset after receiving a MU EDCA reset frame, the STA may update CWmin[AC], CWmax[AC], and AIFSN[AC] to the values ​​included in the most recently received EDCA parameter set element sent by the AP to which the STA is associated.

[0189] A non-AP HE STA that sends a frame with the OM Control subfield set to 1, or with the UL MU Disable subfield set to 0 and the UL MU Data Disable subfield set to 1, may set MUEDCATimer[AC] to 0 for all ACs after receiving an immediate ACK from the OMI responder.

[0190] The STA may perform the current EDCA backoff procedure without modifying the backoff counter for QSRC[AC], QLRC[AC], or the associated EDCAF, regardless of whether MUEDCATimer[AC] reaches zero, until a new EDCA backoff procedure is invoked.

[0191] In response to a MUEDCATimer[AC] reset, the STA may invoke a new EDCA backoff procedure after resetting MUEDCATimer[AC] for that AC and after updating CWmin[AC], CWmax[AC], and AIFSN[AC] for that AC.

[0192] That is, during the time set in the MU EDCA timer subfield, the priority of the MU EDCA associated with the AC indicated in the MU EDCA parameter set element may be lower than the priority of the AC in the general EDCA operation. Therefore, when the time set in the MU EDCA timer subfield expires, the priority of the AC to which MU EDCA is applied may be restored to the priority they had in the EDCA operation.

[0193] Method for applying MU EDCA to TIDs assigned through TID-to-link mapping

[0194] When MU EDCA is applied to some TIDs assigned to links through TID-to-link mapping, the TIDs may have lower priority for channel access than TIDs to which MU EDCA is not applied.

[0195] Based on the above rules, one or more links between MLDs may be assigned as links for delay-sensitive traffic, and MU EDCA may be utilized to assign priority for channel access to TIDs classified as delay-sensitive traffic.

[0196] Unlike a rule that MU EDCA is applied to a specific AC during a time set by the MU EDCA timer subfield, the present disclosure assumes a case where MU EDCA is continuously applied to an AC corresponding to a TID after the TID to which MU EDCA is applied is indicated by TID-to-link mapping.

[0197] In the following, a method for sending information about which TIDs assigned on one or more links in a TID-to-link mapping are to be applied for MU EDCA is described. The name of the new field proposed to support this method can be changed in various ways.

[0198] Fig.10 1 is a diagram for describing an operation performed by a first STA MLD according to an embodiment of the present disclosure. Fig.10 and Fig.11 In the embodiment, the first STA MLD may mean a non-AP STA MLD, and the second STA MLD may mean an AP MLD, but is not limited thereto. Each of the first STA MLD and the second STA MLD may be at least one of a non-AP STA MLD or an AP MLD.

[0199] The first STA MLD may transmit a specific element including a (LL) MU EDCA MAP field to the second STA MLD, or receive a specific element from the second STA MLD (S1010). That is, the first STA MLD may request information about a link / TID related to the (LL) MU EDCA operation from the second STA MLD, or may receive information about a link / TID related to the (LL) MU EDCA operation from the second STA MLD.

[0200] Here, the specific element may be at least one of a TID-to-link element, an EDCA mapping element, or a LL (Low Latency) EDCA mapping element.

[0201] And, at least one of the TID-to-link element, the EDCA mapping element, or the LL EDCA mapping element may include an EDCA control field and / or an LL EDCA control field. The MU EDCA control field and / or the LL EDCA control field may include a first subfield indicating whether the (LL) MU EDCA mapping field is present in at least one of the TID-to-link element, the EDCA mapping element, or the LL EDCA mapping element.

[0202] The MU EDCA MAP field may include first information related to at least one link performing a (LL) MU EDCA operation and second information related to at least one TID corresponding to the at least one link.

[0203] As an example of the present disclosure, the (LL)MU EDCA Map field may include a second subfield including an ID value of at least one link performing the (LL)MU EDCA operation or a bitmap indicating at least one link. Here, the first information may be indicated by the second subfield.

[0204] Furthermore, the (LL)MU EDCA map field may include at least one third subfield indicating at least one TID associated with the (LL)MU EDCA operation corresponding to at least one link performing the (LL)MU EDCA operation. Here, the second information may be indicated by the at least one third subfield. Furthermore, the number of the at least one third subfield may be equal to the number of the at least one link.

[0205] As an example of the present disclosure, a TID may be configured to a link element based on a MU EDCA parameter set element or a LL MU EDCA parameter set element.

[0206] Here, the LL MU EDCA parameter set element includes a plurality of LL MU TID parameter record fields, and each of the plurality of LL MU TID parameter record fields may include a LL MU EDCA timer subfield.

[0207] When TID-to-link elements are configured based on the LL MU EDCA parameter set element, the (LL) MU EDCA mapping field may be associated with LL MU EDCA operation. At least one link performing LL MU EDCA operation may be indicated by first information, and at least one TID associated with LL MU EDCA operation may be indicated by second information.

[0208] As another example of the present disclosure, the (LL)MU EDCA Map field may include third information related to at least one AC (Access Category) associated with the (LL)MU EDCA operation. The (LL)MU EDCA Map field may include at least one fourth subfield indicating at least one AC corresponding to each of the at least one link. Here, the third information may be indicated by the fourth subfield.

[0209] The first STA MLD may perform a (LL) MU EDCA operation on at least one link based on certain factors ( S1020 ).

[0210] Depend on Fig.10 The method performed by the first STA MLD described in the example may be performed by Figure 1 The first device (100) performs. For example, Figure 1 The one or more processors (102) of the first device (100) may be configured to send a specific element including a MU EDCA map field to a second STA MLD or receive the specific element from the second STA MLD via one or more transceivers (106). The one or more processors (102) may be configured to perform MU EDCA operation on at least one link based on the specific element.

[0211] In addition, the one or more memories (104) of the first device (100) may store instructions for executing, when executed by the one or more processors (102), Fig.10 The method described in the example.

[0212] Fig.11 is a diagram for describing an operation performed by a second STA MLD according to one embodiment of the present disclosure.

[0213] The second STA MLD may generate a specific element including a (LL) MU EDCA map field ( S1110 ).

[0214] For example, the second STA MLD may generate a specific element including a (LL) MU EDCA map field based on the (LL) MU EDCA parameter set element.

[0215] The second STA MLD may transmit a specific element including a MU EDCA MAP field to the first STA MLD ( S1120 ).

[0216] Already referenced Fig.10 Specific elements and configuration of the (LL)MU EDCA mapping fields are described, so a redundant description will be omitted.

[0217] Fig.11 The method performed by the second STA MLD described in the example of Figure 1 The second device (200) executes. For example, Figure 1 The one or more processors (202) of the second device (200) may be configured to generate a specific element including a (LL) MU EDCA MAP field. The one or more processors (202) may be configured to send the specific element including the MU EDCA MAP field to the first STA MLD via the one or more transceivers (206).

[0218] In addition, the one or more memories (204) of the second device (200) may store instructions for executing when executed by the one or more processors (202). Fig.11 Commands for the methods described in the examples.

[0219] The following describes in detail a method for transmitting information regarding which TIDs among TIDs allocated on one or more links are to which MU EDCA is to be applied in a TID-to-link mapping.

[0220] In the case of R (Restricted)-TWT (Target Wake Time), which is a technology for sending and receiving LL services / data in a basic wireless communication system, TWT negotiation operations, rules for stopping the ongoing TXOP before the start time of the R-TWT SP to ensure the corresponding R-TWT SP (service cycle), and overlapping silent intervals allocated to overlap with the corresponding R-TWTSP can be applied.

[0221] The above rules and operations may be disadvantageous to STAs that do not support R-TWT. Therefore, MU EDCA can be utilized in the TID to link mapping process to assign specific links as links for delay-sensitive services and give priority for channel access to TIDs classified as delay-sensitive services.

[0222] The method described by the following embodiments may include a method (UL) in which the STA MLD transmits a TID-to-link element including information about a TID to which MUEDCA is applied and a link on which the corresponding TID operates to the AP MLD, and a method (DL) in which the AP MLD transmits a TID-to-link element including corresponding information to the STA MLD.

[0223] Example 1

[0224] Embodiment 1 relates to a method of transmitting information on which TIDs among TIDs assigned to a link are to be applied for MU EDCA when only one link performs MU EDCA operation based on a MU EDCA parameter set.

[0225] If MU EDCA operation is possible on the link between MLDs, a new field may be included in the TID-to-Link element.

[0226] The new fields proposed in the present disclosure may be based on the format of the TID-to-link element, and the values ​​of the new fields may be based on the values ​​of the MU EDCA parameter set element. The TID-to-link element including the relevant new fields in MU EDCA may be defined as follows: Fig.12 as shown in (a) or (b).

[0227] As an example of the present disclosure, Fig.12 As illustrated in (a) of FIG. 2 , the presence or absence of a link on which MU EDCA operates may be indicated by a MU EDCA presence subfield included in a TID-to-Link Mapping Control field of a TID-to-Link element.

[0228] For example, if the value of the MU EDCA Present subfield is 1 (or 0), the TID to Link element may have a MU EDCA Map field. The MU EDCA Map field may include a "Link ID for MU EDCA" subfield that indicates the ID of the link operating MU EDCA (i.e., the link to which MU EDCA is applied). In addition, the MU EDCA Map field may include a "TID for MU EDCA" subfield that indicates the TID of the link to which MU EDCA is applied as a bitmap.

[0229] The "Link ID for MU EDCA" subfield may have a size of 4 bits to indicate a link ID. The "TID for MU EDCA" subfield may have a size of 8 bits (ie, 1 octet) to indicate as a bitmap whether MU EDCA is applied to each of TID 0 to TID 7. In order to match the length of the MU EDCA Map field to an octet, 4 bits of the MU EDCA Map field may be reserved.

[0230] For example, 12 in FIG. (a) illustrates a case where link 0 is a link performing MU EDCA and ACs to which MU EDCA is applied are ACs corresponding to TIDs 0, 1, 2, and 3. For example, the "Link ID for MU EDCA" subfield may indicate an ID ("0000") of a corresponding link, and the "TID for MU EDCA" subfield may be set to "11110000" to indicate TIDs 0, 1, 2, and 3. Here, the MU EDCA presence field value in the TID to Link Mapping Control field may be set to 1.

[0231] As an example of the present disclosure, Fig.12 As illustrated in (b) of FIG. 1 , the presence or absence of a link on which MU EDCA operates can be indicated by a MU EDCA presence subfield included in a TID-to-Link Mapping Control field of a TID-to-Link element.

[0232] For example, if the corresponding MU EDCA Present subfield value is 1 (or 0), the corresponding TID to Link element may have a MU EDCA Map field. The MU EDCA Map field may include a "Link for MU EDCA Indicator" subfield that bitmaps the MU EDCA indicator indicating a link operating as MU EDCA.

[0233] Here, similar to Fig.12 (a), the MU EDCA Map field may include a "TID for MU EDCA" subfield, which is used to indicate the TID to which MU EDCA is applied on the link.

[0234] The "Links for MU EDCA Indicator" subfield may have a size of 16 bits (i.e., 2 octets) to indicate the maximum number of links that the MLD has. The "TIDs for MU EDCA" subfield may have a size of 8 bits (i.e., 1 octet) to indicate as a bitmap whether MU EDCA of TID 0 to TID 7 is applied, similar to Fig.12 (a).

[0235] The Link subfield for MU EDCA indicator has a size of 16 bits (2 octets) to indicate the maximum number of links that the MLD has in 11be. The TID field for MU EDCA has a size of 8 bits (1 octet) to indicate as a bitmap the application of MU EDCA for TID 0 to TID 7, as in Figure 1 middle.

[0236] As an example, Fig.12 (b) illustrates a case where link 0 is a link performing MU EDCA and the AC to which MU EDCA is applied is the AC corresponding to TIDs 0, 1, 2, and 3. For example, the "Link ID for MU EDCA Indicator" subfield may indicate an ID of the corresponding link ("1000000000000000"), and the "TID for MU EDCA" subfield may be set to "11110000" to indicate TIDs 0, 1, 2, and 3. In this case, the MU EDCA Present field value in the TID to Link Mapping Control field may be set to 1.

[0237] Example 2

[0238] Embodiment 1 relates to a method of transmitting information on which TIDs among TIDs assigned to links are to be applied for MU EDCA when one or more links perform MU EDCA operation based on a MU EDCA parameter set.

[0239] If MU EDCA operation is possible on one or more links between MLDs, a new field may be included in the TID-to-Link element.

[0240] The new fields proposed in the present disclosure may be based on the format of the TID to Link element, and the value of the new field may be based on the value of the MU EDCA parameter set element. The TID to Link element including the relevant new fields in MU EDCA may be defined as follows: Fig.13 (a) Fig.13 (b) or Fig.13 (c).

[0241] like Fig.13As illustrated in (a), when MU EDCA operation is applied to one or more links, the TID-to-link element can indicate the presence or absence of a link on which MU EDCA operates through the MU EDCA presence subfield in the TID-to-link mapping control field.

[0242] For example, when the MU EDCA Present subfield value is set to 1, the corresponding TID to Link element may include a MU EDCA Map field. The MU EDCA Map field may indicate the ID of the link to which MU EDCA is applied through a "Link ID for MU EDCA" subfield.

[0243] In addition, the MU EDCA Map field may include a TID for MU EDCA on Link N ("TID for MU EDCA on Link N") subfield, which represents the TID for operating MU EDCA on each link as a bitmap.

[0244] The name of the Link ID for MU EDCA subfield can be the same as Fig.12 The names of the corresponding fields in (a) are the same. Fig.12 The fields shown in (a) are different. Fig.13 The "Link ID for MU EDCA" subfield illustrated in (a) of FIG. 1 can indicate the link ID to which MU EDCA is applied in an array form. Therefore, Fig.13 The length of the "Link ID for MU EDCA" subfield illustrated in (a) of FIG. 1 may be variable. For example, the length of the "Link ID for MU EDCA" subfield is (m = 4 bits * number of link IDs) and can have a maximum of 64 bits (8 octets).

[0245] The 'TID for MU EDCA on Link N' subfield can correspond a link ID indicated in an array form to link N (N=0, 1, ... 15). Therefore, the 'TID for MU EDCA on Link N' subfield can indicate information on whether MU EDCA is applied to TIDs 0 to 7 on each link as a bitmap, and can have a size of 8 bits (1 octet).

[0246] The maximum length that the MU EDCA MAP field can have is 192 bits (ie, 24 octets). Here, the number of link IDs indicated by the "Link ID for MU EDCA" subfield and the number of "TIDs for MU EDCA on Link N" subfields can be the same.

[0247] For example, Fig.13As shown in (a), when MU EDCA is applied to one link ID, the 'Link ID for MU EDCA' subfield may have a length of 8 bits (1 octet). And, the 'Link ID for MU EDCA' subfield may have a value of the 5th to 8th bits set to 0. This means link 0, but the 'TID for MU EDCA on link 0' subfield may not be included in the corresponding TID to link element.

[0248] In the above case, if link 0 is indicated by one link ID, the "Link ID for MU EDCA" subfield value having a length of 8 bits (1 octet) may have "0000000". And, the corresponding TID to Link element may include one "TID for MU EDCA Link 0" subfield.

[0249] For example, when MU EDCA is applied to link 0 and link 15, it is assumed that the TID to which MU EDCA is applied in link 0 corresponds to TIDs 0 and 1, and the TID to which MU EDCA is applied in link 15 corresponds to TIDs 0, 1, 2, and 3. Here, the value of the MU EDCA presence field in the TID to Link Mapping Control field can be set to 1. In addition, the "Link ID for MU EDCA" subfield indicates a link in an array form, and can have values ​​of "0000" and "1111". In order to indicate information on the TID to which MU EDCA is applied in each link, the value of the "TID for MU EDCA on Link 0" subfield can be set to "11000000", and the value of the "TID for MU EDCA on Link 15" subfield can be set to "11110000".

[0250] As another example of the present disclosure, Fig.13 As illustrated in (b), when MU EDCA operation is applied to one or more links, the presence or absence of the link on which MU EDCA operates can be indicated by the MU EDCA presence subfield in the TID to link mapping control field of the TID to link element. For example, when the value of the MU EDCA presence subfield is 1 (or 0), the corresponding TID to link element can have a MU EDCA mapping field.

[0251] The MU EDCA Map field may include a "Link for MU EDCA Indicator" subfield, which indicates as a bitmap the links on which MU EDCA operates. It may include a "TID for MU EDCA on Link N (N = 0, 1, ..., 15)" subfield, which indicates as a bitmap the TID on which MU EDCA operates on each link.

[0252] The "Links for MU EDCA Indicator" subfield may have a size of 10 bits (2 octets) to indicate the maximum number of links that the MLD can have, similar to Fig.12 (b) in the figure.

[0253] The "TID for MU EDCA Link N" subfield may indicate TID information on application of MU EDCA on a link indicated as a link on which MU EDCA operates in the "Link for MU EDCA Indicator" subfield. That is, the number of 1s in the "Link for MU EDCA Indicator" subfield and the number of "TID for MU EDCA on Link N" subfields may be the same.

[0254] For example, when MU EDCA is applied to link 0 and link 15, it is assumed that the TID to which MU EDCA is applied in link 0 corresponds to TIDs 0 and 1, and the TID to which MU EDCA is applied in link 15 corresponds to TIDs 0, 1, 2, and 3. Here, the value of the MU EDCA presence field in the TID to Link Mapping Control field can be set to 1. In addition, the "Link for MU EDCA Indicator" subfield can indicate a link in a bitmap form, and may have a value of "100000000000001". In order to indicate information on the TID to which MU EDCA is applied in each link, the "TID for MU EDCA on Link 0" subfield value may be set to "11000000", and the "TID for MU EDCA on Link 15" subfield value may be set to "11110000".

[0255] As another example of the present disclosure, Fig.13 As illustrated in (c) of FIG. 1 , when MU EDCA operation is performed on one or more links, the presence or absence of the link on which MU EDCA is performed can be indicated by the MU EDCA presence subfield in the TID to link mapping control field of the TID to link element. If the value of the corresponding MU EDCA presence subfield is 1 (or 0), the corresponding TID to link element can have a MU EDCA mapping field.

[0256] The MU EDCA Map field may include a MU EDCA Indicator subfield and a "For MU EDCA Link on TID n" subfield and may have a length of up to 17 octets.

[0257] The link to which MU EDCA is applied may be indicated by a value of 1 in a subfield corresponding to each TID. Here, the presence or absence of a subfield corresponding to each TID is indicated by 1 or 0 by the MU EDCA Indication field, and may have a length of 1 octet to indicate TID 0 to TID 7 as a bitmap. If the MU EDCA Indication field value is set to 1, the presence of a subfield of the corresponding TID may be indicated.

[0258] That is, when a specific bit of the bitmap corresponding to TID 0 to TID 7 in the MU EDCA indicator subfield is set to 1, it may mean that the corresponding TID is a TID to which MU EDCA is applied. The subfield of the corresponding TID may be located such that the "Link for MU EDCA on TID n'" subfield is located after the MU EDCA indicator subfield.

[0259] In order to indicate links to which MUEDCA is applied for corresponding TID n in each "Links for MU EDCA on TID n'" subfield, a bitmap corresponding to each link has a value of 1 or 0, and each subfield can have a length of 2 octets in order to indicate all links using a bitmap.

[0260] For example, assume that the TIDs to which MU EDCA is applied are TIDs 0, 1, 2, and 3, and MU EDCA operates on links 0, 1, 2, 13, 14, and 15. Fig.13 As illustrated in (c) of FIG. 1 , the MU EDCA indicator subfield can indicate that MU EDCA is applied to TIDs 0, 1, 2, and 3 with a value of “11110000”.

[0261] In addition, if Fig.13 As illustrated in (c) of FIG. 1 , there may be a “Link for MU EDCA on TID n′” subfield corresponding to TID n having a value of 1. Here, the “Link for MU EDCA on TID 0′” subfield, the “Link for MU EDCA on TID 1′” subfield, the “Link for MU EDCA on TID 2′” subfield, and the “Link for MU EDCA on TID 3′” subfield may be arranged in this order after the “MU EDCA Indicator” subfield.

[0262] And, the MU EDCA Map field has a total length of 9 octets. Since the "Links for MU EDCA on TID 0" subfield value is set to "1110000000000111", it can be indicated that TID 0 to which MU EDCA is applied operates on links 0, 1, 2, 13, 14, and 15. Other "Links for MU EDCA on TID 1" subfields, "Links for MU EDCA on TID 2" subfields, and "Links for MU EDCA on TID 3" subfields may also have the same value (ie, "1110000000000111"). Therefore, it can be indicated that the TID to which MU EDCA is applied operates on links 0, 1, 2, 13, 14, and 15.

[0263] Fig.13 (c) illustrates a case where the TIDs for applying MU EDCA on links 0, 1, 2, 3, 13, 14, and 15 are the same. However, this is merely an example, and the TIDs for applying MU EDCA on each link may be different. For example, the TIDs for applying MU EDCA on link 0 and link 1 may be TID 0 and TID 3, and the TIDs for applying MU EDCA on link 3 may be TID 1 and TID 2.

[0264] Example 3

[0265] Embodiment 3 relates to a method of transmitting information on which TIDs among TIDs assigned to a link are to be applied with MU EDCA when MU EDCA is applied to only one link based on a LL MU EDCA parameter set.

[0266] Assuming that MU EDCA can operate on a single link between MLDs, relevant new fields can be added to the TID-to-Link element.

[0267] The new fields described in this disclosure are based on the format of "TID to Link Element", and the new field values ​​may be based on the values ​​of the new Low Latency (LL) MU EDCA parameter set element. LL MU EDCA parameter set means an EDCA parameter set for LL data.

[0268] The LL MU EDCA parameter set elements of the present disclosure can be as follows: Fig.14 The (a) and (b) are defined. Fig.14 The name and length of each field of the LL MU EDCA parameter set element shown in (a) can vary.

[0269] like Fig.14As illustrated in (a), a total of 8 LL MU TID n parameter record fields having a length of 3 octets corresponding to TID 0 to TID 7 may be located after the QoS information field of the LL MU EDCA parameter set element.

[0270] Each LL MU TID n parameter record field can be as follows Fig.14 Here, each LL MUTID n parameter record field may be configured in the same manner as the MU AC parameter record field format field in the above-mentioned MU EDCA parameter set element.

[0271] As an example of the present disclosure, Fig.14 As illustrated in (c) of FIG. 1 , the TID-to-Link element may indicate the presence or absence of a link on which MU EDCA operates via the LL MU EDCA Presence subfield in the TID-to-Link Mapping Control field.

[0272] For example, when the value of the corresponding LL MU EDCA Present subfield is 1 (or 0), the corresponding TID to Link element may have an LL MU EDCA Mapping field. The LL MU EDCA Mapping field may include a "Link ID for LL MU EDCA" subfield, which indicates the link on which MU EDCA operates by means of a link ID. In addition, the LL MU EDCA Mapping field may include a "TID for LL MU EDCA" subfield, which indicates, as a bitmap, the TID of the corresponding link to which MU EDCA is applied.

[0273] The "Link ID for LL MU EDCA" subfield may have a size of 4 bits to indicate a link ID. The "TID for LL MU EDCA" subfield may have a size of 8 bits (ie, 1 octet) to indicate whether MU EDCA of TID0 to TID 7 is applied as a bitmap. In order to set the length of the LL MU EDCA Map field in units of octets, the LL MU EDCA Map field may have 4 reserved bits.

[0274] For example, when MU EDCA operates / is applied to link 0, it is assumed that the AC to which MU EDCA is applied is the AC corresponding to TIDs 0, 1, 2, and 3. Therefore, the value of the LL MU EDCA presence field in the TID to Link Mapping Control field may be indicated as 1. Also, the value of the 'Link ID for LL MU EDCA' subfield may be set to '0000', and the 'TID for LL MU EDCA' field may have a value of '11110000' to indicate TIDs 0, 1, 2, and 3.

[0275] As an example of the present disclosure, Fig.14 As shown in (d), the TID to link element may include a LL MU EDCA presence subfield. The LL MU EDCA presence subfield of the TID to link element may be Fig.14 The LL MUEDCA present subfield is the same as that illustrated in (c).

[0276] The LL MU EDCA Map field may include a "Link for LL MU EDCA Indicator" which indicates the link on which MU EDCA operates based on a bitmap. Fig.14 Similar to (c), the LL MU EDCA Map field may include a "TID for LL MU EDCA" subfield, which is used to indicate the TID of MU EDCA applied on the corresponding link.

[0277] The "Links for LL MU EDCA Indicator" subfield may have a size of 16 bits (2 octets) to indicate the maximum number of links that the MLD has. The "TIDs for LL MU EDCA" field may have a size of 8 bits (1 octet) to indicate whether MU EDCA of TID 0 to TID 7 is applied based on a bitmap.

[0278] For example, when MU EDCA operates / is applied to link 0, it is assumed that the AC to which MU EDCA is applied is the AC corresponding to TIDs 0, 1, 2, and 3. Therefore, the value of the LL MU EDCA presence field in the TID to Link Mapping Control field may be indicated as 1. Also, the value of the "Link ID for LL MU EDCA Indicator" subfield based on the bitmap is set to "1000000000000000", and the "TID for LL MU EDCA" field can have a value of "11110000" to indicate TIDs 0, 1, 2, and 3.

[0279] Example 4

[0280] Embodiment 4 relates to a method of transmitting information on which TIDs among TIDs assigned to links are to be applied with MU EDCA when MU EDCA is applied only to one or more links based on an LL MU EDCA parameter set.

[0281] Assuming that one or more links between the MLDs are capable of MU EDCA operation, the TID-to-link element may include new fields. The new fields described in this disclosure are based on the format of the "TID-to-link element", and the new field values ​​may be based on the values ​​of the new low latency (LL) MU EDCA parameter set element. LL MU EDCA parameter set means an EDCA parameter set for LL data. LL MU EDCA parameter set means an EDCA parameter set for LL data.

[0282] The LL MU EDCA parameter set elements of the present disclosure may be as follows: Fig.14 The (a) and (b) are defined. Fig.14 The name and length of each field of the LL MU EDCA parameter set element shown in (a) may vary.

[0283] Fig.14 (a) LL MU EDCA parameter set elements and Fig.14 Each LL MU TID n parameter record field illustrated in (b) has been described in Example 3, so redundant description is omitted.

[0284] like Fig.15 As shown in (a), when MU EDCA operation is applied to one or more links, the TID to link element can indicate the presence or absence of the link on which MU EDCA operation is performed through the LL MU EDCA presence subfield in the TID to link mapping control field. When the value of the LL MU EDCA presence subfield is 1, the TID to link element may have the LLMU EDCA mapping field.

[0285] The LL MU EDCA Map field may indicate the ID of the link on which MU EDCA operates via the "Link ID for LL MU EDCA" subfield. The LL MU EDCA Map field may include a "TID for LLMU EDCA on Link N (N = 0, 1, ..., 15)" subfield, which indicates the TID of MU EDCA operating on each link based on a bitmap.

[0286] The "Link ID for LL MU EDCA" subfield can indicate the link ID in the form of an array. Fig.14 Unlike the “Link ID for LL MU EDCA” subfield in (c) having a length of 4 bits, the “Link ID for LL MU EDCA” subfield can have a variable value.

[0287] Here, the length of the "Link ID for LL MU EDCA" subfield is (m = 4 bits * the number of link IDs), and may have a maximum of 64 bits (8 octets). The 'TID for LL MU EDCA on Link N' subfield may correspond to a link ID indicated in an array form for link N (N = 0, 1, ..., 15). Therefore, the 'TID for LL MU EDCA on Link N' subfield may indicate information on whether MU EDCA applies TID 0 to TID 7 on each link based on a bitmap, and may have a size of 8 bits (1 octet).

[0288] Therefore, the LL MU EDCA MAP field can have a maximum length of 192 bits (24 octets).Here, the number of link IDs indicated by the "Link ID for LL MU EDCA" subfield and the number of "TIDs for LL MU EDCA on Link N" subfields can be the same.

[0289] like Fig.15 As illustrated in (a) of FIG. 1 , when the "Link ID for LL MU EDCA" subfield has one link ID, the field may have a length of 8 bits (1 octet). And, bit values ​​5 to 8 of the field may be set to 0.

[0290] This means link 0, but the "TID for LL MU EDCA on Link 0" subfield may not be included in the corresponding TID to Link element. For example, if a link ID indicates link 0, the "Link ID for LL MU EDCA" subfield having a length of 8 bits (1 octet) has a value of "0000000", and the corresponding TID to Link element may include a "TID for LL MU EDCA Link 0" subfield.

[0291] For example, when MU EDCA is applied to link 0 and link 15, it is assumed that the TID to which MU EDCA is applied in each link corresponds to TIDs 0 and 1 in link 0 and TIDs 0, 1, 2, and 3 in link 15. Therefore, the value of the LL MU EDCA presence field in the TID to Link Mapping Control field may be set to 1. The "Link ID for LL MU EDCA" subfield may be set to "0000" and "1111". In order to indicate information on the TID to which MU EDCA is applied in each link, the value of the "TID for LL MU EDCA on Link 0" subfield may be set to "11000000", and the value of the "TID for LL MU EDCA on Link 15" subfield may be set to "11110000".

[0292] As an example of the present disclosure, Fig.15 As shown in (b), the TID to link element may include the LL MU EDCA presence subfield. The LL MU EDCA presence subfield of the TID to link element may be Fig.15 The TID illustrated in (a) is the same as the LL MU EDCA Presence subfield of the link element.

[0293] The LL MU EDCA Map field may include a "Link for LL MU EDCA Indicator" subfield that indicates the link on which MU EDCA operates based on a bitmap. It may include a "TID for LL MU EDCA on Link N (N = 0, 1, ..., 15)" subfield that indicates the TID on which MU EDCA operates on each link using a bitmap.

[0294] The "Link for LL MU EDCA Indicator" subfield may have a size of 16 bits (2 octets) to indicate the maximum number of links that the MLD can have. The "TID for LL MU EDCA Link N" subfield can indicate TID information of applying MU EDCA on the link indicated in the "Link for LL MU EDCA Indicator" subfield as the link on which MU EDCA operates.

[0295] That is, the number of 1s in the "Link for LL MU EDCA Indicator" subfield and the number of the "TID for LLMU EDCA on Link N" subfield may be the same.

[0296] For example, when MU EDCA is applied to link 0 and link 15, it is assumed that the TID to which MU EDCA is applied in each link corresponds to TIDs 0 and 1 in link 0 and TIDs 0, 1, 2, and 3 in link 15. Therefore, the value of the LL MU EDCA presence field in the TID to Link Mapping Control field may be set to 1. The "Link for LL MU EDCA Indicator" subfield may have "10000000000001". In order to indicate information of the TID to which MU EDCA is applied in each link, the value of the "TID for LL MU EDCA on Link 0" subfield may be set to "11000000", and the value of the "TID for LL MU EDCA on Link 15" subfield may be set to "11110000".

[0297] As another example of the present disclosure, Fig.15 As shown in (c), the TID to Link Element may include a LL MU EDCA Present subfield. The LL MU EDCA Present subfield may be associated with Fig.15 The LL MU EDCA present subfield is the same as that illustrated in (a).

[0298] The LL MU EDCA Map field may include the LL MU EDCA Indicator subfield and the "For LL MU EDCA Link on TID n" subfield and may have a length of up to 17 octets.

[0299] The link on which MU EDCA operates may be indicated by a value of 1 in the subfield corresponding to each TID. Here, the presence or absence of the subfield corresponding to each TID may be indicated by 1 (i.e., presence) and 0 (i.e., absence) in the "LL MU EDCA Indicator Subfield". The "LL MU EDCA Indicator Subfield" may have a length of 1 octet to indicate TIDs 0 to 7 based on a bitmap.

[0300] That is, if the bitmap corresponding to TID 0 to TID 7 in the LL MU EDCA indicator subfield has a value of 1, it may mean that the corresponding TID is a TID to which MU EDCA is applied. In addition, the subfield of the corresponding TID, the "Link for LLMU EDCA on TID n" subfield may be located after the LL MU EDCA indicator subfield.

[0301] To indicate links to which MU EDCA is applied for corresponding TID n in each "Links for LL MU EDCA on TID n" subfield, a bitmap corresponding to each link may have a value of 1 or 0. To indicate all links based on the bitmap, each subfield may have a length of 2 octets.

[0302] For example, the TIDs to which MU EDCA is applied are TIDs 0, 1, 2, 3, and this assumes the case of operating on links 0, 1, 2, 13, 14, 15. In this case, the LL MU EDCA indicator subfield value is set to '11110000', which means that MU EDCA is applied to TIDs 0, 1, 2, 3.

[0303] In addition, there may be a 'Link for LL MU EDCA on TID n' subfield corresponding to TID n having a value of 1. Within the LL MU EDCA Map field, the 'Link for LL MU EDCA on TID 0' subfield, the 'Link for LL MU EDCA on TID 1' subfield, the 'Link for LL MU EDCA on TID 2' subfield, and the 'Link for LL MU EDCA on TID 3' subfield may be arranged in this order after the LL MU EDCA Indicator subfield.

[0304] The LL MU EDCA Map field may have a total length of 9 octets. The value of the "Links for LL MU EDCA on TID 0" subfield may be set to "1110000000000111". This means that TID 0 with applied MU EDCA operates on links 0, 1, 2, 13, 14, and 15. Here, the "Links for LL MU EDCA on TID 1" subfield, the "Links for LL MU EDCA on TID 2" subfield, and the "Links for LL MU EDCA on TID 3" subfield may also have the same value. This may mean that the TID with applied MU EDCA operates on links 0, 1, 2, 13, 14, and 15.

[0305] exist Fig.15 In the case of (c), the TIDs for applying MU EDCA on links 0, 1, 2, 3, 13, 14, and 15 are the same, but not limited thereto. The TIDs for applying MU EDCA on each link may be different. For example, the TIDs for applying MU EDCA on links 0 and 1 may be TID 0 and TID 3, and the TIDs for applying MU EDCA on link 3 may be TID 1 and TID 2.

[0306] Example 5

[0307] Embodiment 5 relates to a method of indicating MU EDCA applied to a TID of a link through a new element.

[0308] Specifically, in Embodiments 1 to 4, a case is described in which MU EDCA application information included in a TID to Link Mapping element is signaled together when a TID to Link Mapping element is signaled. Embodiment 5 relates to a method of transmitting and receiving information about MU EDCA applied among TIDs mapped on each link through an element separate from the TID to Link Mapping element.

[0309] like Fig.16 As shown in (a) and (b) of , the novel elements proposed in the present disclosure may be based on the MU EDCA parameter set elements. If the LL MU EDCA parameter set elements disclosed in Embodiments 3 and 4 exist, the new elements may be based on the LL MU EDCA parameter set. Here, the LL EDCA parameter set means an EDCA parameter set for LL data and may be expressed by various names.

[0310] The new element of the present disclosure may be sent separately from the TID to link mapping element. As another example, for use with the TID to link mapping element, the new element may be sent after sequence 4 (e.g., sequence 5) on the TID to link mapping request / response frame action field. Fig.16 As illustrated in (a) and (b) of FIG. 1 , the name of the new LL EDCA mapping element and the names of the fields included therein can be implemented in various ways.

[0311] New LL EDCA mapping elements based on the elements defined in Embodiments 1 and 3 may be as follows: Fig.16 The configurations shown in (a) and (b) are shown. Fig.16 The LL EDCA mapping element illustrated in (a) may indicate a link operating MU EDCA using a link ID, and Fig.16 The LL EDCA mapping element illustrated in (b) may indicate a link operating MU EDCA through a bitmap.

[0312] For example, the LL EDCA Control field of the LL EDCA Map element may include a Direction subfield, a Map Switch Time Present subfield, an Expected Duration Present subfield, and a LL EDCA Present subfield.

[0313] The Direction subfield may indicate UL or DL ​​(or P2P), the Map Switching Time Exists subfield indicates whether the Map Switching Time field exists, the Expected Duration Exists subfield indicates whether the Expected Duration field exists, and the LL EDCA Exists subfield can indicate whether the LL EDCA Mapping field exists.

[0314] A Mapping Switching Time subfield and an Expected Duration Subfield exist on the LL EDCA Control field, and these subfields may be used as timers used when a TID to which MU EDCA is applied operates on a link in the TID to Link Mapping subfield.

[0315] Fig.16 The LL EDCA Map field in (a) may include a "Link ID for LL EDCA" subfield indicating a link ID on which MU EDCA operates. In addition, the LL EDCA Map field may include a "TID for LL EDCA" subfield indicating a TID for applying MU EDCA to a corresponding link through a bitmap.

[0316] The 'Link ID for LL EDCA' subfield has a size of 4 bits to indicate a link ID, and the 'TID for LLEDCA' field may have a size of 8 bits (1 octet) to indicate as a bitmap whether MU EDCA is applied for TID 0 to TID 7. In order to match the length of the LL EDCA Map field with an octet, the LL EDCA Map field may have 4 reserved bits.

[0317] Fig.16 The LL EDCA Map field in (b) may include a "Link for LL EDCA Indicator" subfield in the form of a bitmap indicating a link on which MU EDCA operates. The LL EDCA Map field may include a "TID for LL EDCA" subfield for indicating a TID on which MU EDCA is applied on a corresponding link.

[0318] The "Links for LL EDCA Indicator" subfield may have a size of 16 bits (2 octets) to indicate the maximum number of links that the MLD has. The "TID for LL EDCA field" may have a size of 8 bits (1 octet) to indicate whether MU EDCA for TID 0 to TID 7 is applied as a bitmap.

[0319] For example, when MU EDCA is applied to link 0, it is assumed that the ACs to which MU EDCA is applied are ACs corresponding to TIDs 0, 1, 2, and 3. Fig.16 As shown in (a) and (b) of FIG. 1 , the value of the LL EDCA presence field in the LL EDCA control field may be indicated as 1. However, Fig.16 As shown in (a) of FIG. 1 , the value of the “Link ID for LL EDCA” subfield may be set to “0000”, and Fig.16 As illustrated in (b) of , the value of the bitmap-based 'Link for LL EDCA indicator' subfield may be set to '1000000000000000'. In order to indicate TIDs 0, 1, 2, and 3, the value of the 'TID for LL EDCA' field may be set to '11110000'.

[0320] New LL EDCA mapping elements based on the elements defined in Embodiments 2 and 4 can be as follows Fig.17 are configured as shown in (a), (b) and (c).

[0321] Fig.17 (a) A method of indicating a link to which MU EDCA is applied using a link ID is exemplified. Fig.17 (b) illustrating a method of indicating a link to which MU EDCA is applied using a bitmap, and Fig.17 (c) illustrates a method of indicating a TID to which MU EDCA is applied using a bitmap and indicating a link through a field corresponding to each TID.

[0322] The configuration and mapping of the LL EDCA control field of the corresponding element and the description of the switching time field / expected interval field have been described above, so any repeated description will be omitted.

[0323] exist Fig.17 In the LL EDCA Map field in (a) of FIG. 1 , the ID of the link on which MU EDCA operates may be indicated by the "Link ID for LL EDCA" subfield. The LL EDCA Map field may include a "TID for LL EDCA on Link N (N = 0, 1, ..., 15)" subfield, which indicates the TID of MU EDCA operating on each link as a bitmap.

[0324] The "Link ID for LL EDCA" subfield can indicate the link ID in an array format, so it can have a variable length. Here, the length of the field is (m = 4 bits * number of link IDs) and can have a maximum of 64 bits (8 octets).

[0325] Therefore, the "TID for LL EDCA on Link N" subfield may correspond to a link ID indicated in an array form for link N (N=0, 1, ..., 15). Therefore, information on whether MU EDCA is applied to TIDs 0 to 7 on each link may be indicated as a bitmap and may have a size of 8 bits (1 octet). Therefore, the LL EDCA Map field may have a maximum length of 192 bits (24 octets).

[0326] Here, the number of link IDs indicated in the "Link ID for LL EDCA on Link N" subfield and the number of "TID for LL EDCA on Link N" subfields may be the same.

[0327] exist Fig.17In case of (a), if the "Link ID for LL EDCA" subfield has one link ID, the field has a length of 8 bits (1 octet) and the 5th to 8th bit values ​​of the field may be set to 0. This means link 0, but the "TID for LL EDCA on link 0" subfield may not be included in the corresponding TID to Link element. In the above case, if one link ID indicates link 0, the "Link ID for LL EDCA" subfield having a length of 8 bits (1 octet) may have "0000000", and the corresponding TID to Link element may include one "TID for LL EDCA Link 0" subfield.

[0328] exist Fig.17 In (b), the LL EDCA Map field may include a "Link for LL EDCA Indicator" subfield, which indicates a link operating MU EDCA as a bitmap.

[0329] It may include a "TID for LL EDCA on Link N (N = 0, 1, ..., 15)" subfield, which indicates the TID for operating MU EDCA on each link as a bitmap. The "Link for LL EDCA Indicator" subfield may have a size of 16 bits (2 octets) to indicate the maximum number of links that the MLD can have.

[0330] The "TID for LL EDCA Link N" subfield may indicate TID information of applying MU EDCA on a link indicated as a link on which MU EDCA operates in the "Link for LL EDCA Indicator" subfield. That is, the number of 1s in the "Link for LL EDCA Indicator" subfield and the number in the "TID for LL EDCA on Link N" subfield may be the same.

[0331] Fig.17 The LL EDCA Map field in (c) may consist of an LL EDCA Indicator subfield and a "Link for LL EDCA on TID n" subfield, and may have a length of up to 17 octets. The link on which MU EDCA operates may be indicated by a value of 1 in a subfield corresponding to each TID. Here, the presence or absence of a subfield corresponding to each TID by the LL EDCA Indicator subfield may be indicated as 1 (i.e., present) or 0 (i.e., absent). The presence or absence of a subfield corresponding to each TID may have a length of 1 octet to indicate TID 0 to TID 7 as a bitmap.

[0332] That is, if the bitmap corresponding to TID 0 to TID 7 in the LL EDCA indicator subfield has a value of 1, it may mean that the corresponding TID is a TID to which MU EDCA is applied. In addition, the subfield of the corresponding TID may be located such that the "Link for LL EDCA on TID n" subfield is located after the LL EDCA indicator subfield.

[0333] In order to indicate the links to which MUEDCA is applied for the corresponding TID n in each "Links for LL EDCA on TID n" subfield, the bitmap corresponding to each link has a value of 1 or 0, and each subfield may have a length of 2 octets in order to indicate all links using the bitmap.

[0334] For example, when MU EDCA is applied to link 0 and link 15 , it is assumed that TIDs to which MU EDCA is applied in link 0 are TIDs 0 and 1 , and TIDs to which MU EDCA is applied in link 15 are TIDs 0 , 1 , 2 , and 3 .

[0335] Here, if Fig.17 As shown in (a) and (b), the value of the LL EDCA Presence field in the LL EDCA Control field may be set to 1. However, because Fig.17 (a) indicates the link ID in array form, so the "Link ID for LL EDCA" subfield value can be set to "0000" and "1111". Fig.17 In (b), the link is indicated as a bitmap, so the "Link for LL EDCA Indicator" subfield value may be set to "1000000000000001".

[0336] To indicate the TID information for each link to which MU EDCA is applied, Fig.17 The value of the “TID for LL EDCA on Link 0” subfield of (a) and (b) may be set to “11000000”, and the value of the “TID for LL EDCA on Link 15” subfield may be set to “11110000”.

[0337] As another example of the present disclosure, it is assumed that TIDs to which MU EDCA is applied are TIDs 0, 1, 2, and 3, and they operate on links 0, 1, 2, 13, 14, and 15.

[0338] here, Fig.17 A value of the 'LL EDCA Indicator' subfield in (c) is set to '11110000', which can indicate that MU EDCA is applied to TIDs 0, 1, 2, and 3.

[0339] In addition, a "Links for LL EDCA on TID n" subfield corresponding to TID n with a value of 1 may be present in the LL EDCA Map field. Fig.17 As illustrated in (c) of , the “Linkage for LL EDCA on TID 0” subfield, the “Linkage for LL EDCA on TID 1” subfield, the “Linkage for LL EDCA on TID 2” subfield, and the “Linkage for LL EDCA on TID 3” subfield may be arranged after the LL EDCA indicator subfield.

[0340] And, if Fig.17 As illustrated in (c) of FIG. 1 , the LL EDCA Map field may have a total length of 9 octets. The "Links for LL EDCA on TID 0" subfield value may be set to "1110000000000111" and may indicate that TID 0 with MU EDCA applied will operate on links 0, 1, 2, 13, 14, and 15.

[0341] Since the other "Links for LL EDCA on TID 1" subfield, "Links for LL EDCA on TID 2" subfield, and "Links for LL EDCA on TID 3" subfield also have the same value, it can be indicated that the TID with applied MU EDCA will operate on links 0, 1, 2, 13, 14, and 15.

[0342] Fig.17 (c) illustrates a case where the TID for applying MU EDCA on links 0, 1, 2, 3, 13, 14, and 15 is the same, but the TID for applying MU EDCA on each link may be different. For example, the TID for applying MU EDCA on link 0 and link 1 may be TID 0 and TID 3, and the TID for applying MU EDCA on link 3 may be TID 1 and TID 2.

[0343] Example 6

[0344] Embodiment 6 relates to a method for indicating whether to use a MU EDCA parameter set based on an AC. Specifically, Embodiments 1 to 5 relate to a method for indicating TID operation based on a (LL) MU EDCA parameter set. Embodiment 6 relates to a method for indicating that an AC uses a (LL) MU EDCA parameter set.

[0345] (LL) The method of indicating that AC uses MU EDCA parameter set may be based on the method according to embodiments 1 to 5. Therefore, the assumptions and rules of TID to link mapping to which the method proposed in embodiment 6 is applied may be the same as those described in embodiments 1 to 5.

[0346] As an example of the present disclosure, Fig.18 (a) shows the link ID and the TID of the AC to the link element when MU EDCA is operated on only one link. The "AC for MU EDCA" subfield may be used instead of the TID based on Fig.12 The TID illustrated in (a) is transferred to the “TID for MU EDCA” subfield of the link element.

[0347] For example, the "AC for MU EDCA" subfield has a length of 4 bits, and each bit can mean AC_BK, AC_BE, AC_VI, AC_VO. In this case, if the value of each bit is set to 1, it can mean that the MU EDCA parameter set is applied to the corresponding AC.

[0348] The "AC for LL (MU) EDCA" subfield may be used instead. Fig.14 The "TID for LL MUEDCA" subfield in (c) and Fig.16 The "TID for LL EDCA" subfield in (a) of Fig.12 MU EDCA mapping field in (a), Fig.14 (c) LL MU EDCA mapping fields and Fig.16 The (a) LL EDCA Map field has a length of 2 octets, but Fig.18 The MU EDCA Map field of (a) may have 1 octet.

[0349] Fig.18 (b) shows the TID to link element indicating the link with AC and bitmap when MU EDCA operates on only one link. Fig.18 (b) As shown in the figure, based on Fig.12 The TID-to-link element illustrated in (b) may apply the "AC for MU EDCA" subfield instead of the "TID for MU EDCA" subfield.

[0350] The "AC for MU EDCA" subfield has a length of 4 bits, and each bit may mean AC_BK, AC_BE, AC_VI, AC_VO. In this case, if the value of each bit is set to 1, it may mean that the MU EDCA parameter set is applied to the corresponding AC.

[0351] For example, the "AC for LL (MU) EDCA" subfield may be used instead of Fig.14 The "TID for LLMU EDCA" subfield in (d) and Fig.16 The "TID for LL EDCA" subfield in (b)

[0352] For example, when MU EDCA operates on link 0, it is assumed that the ACs to which MU EDCA is applied are AC_BK and AC_BE. Fig.18 As shown in (a) and (b), the value of the MU EDCA Presence field in the TID-to-Link Mapping Control field can be set to 1.

[0353] here, Fig.18 The value of the "Link ID for MU EDCA" subfield in (a) is set to "0000", and based on Fig.18 The bitmap of (b) indicates that the “Link for MU EDCA Indicator” subfield value of the link may be set to “10000000000000000”. In order to indicate AC_BK, AC_BE, the “AC for MU EDCA” field value may be set to “1100”.

[0354] As another example of the present disclosure, Fig.19 (a) shows the application of the "AC for MU EDCA on link n" subfield instead of Fig.13 1. The case of the "TID for MU EDCA on link n" subfield illustrated in (a) of . Each of the "AC for MU EDCA on link n" subfields has a length of 4 bits, and each bit can mean AC_BK, AC_BE, AC_VI, and AC_VO. In this case, when the value of each bit is set to 1, it means that the MU EDCA parameter set is applied to the corresponding AC.

[0355] The "AC for LL (MU) EDCA on Link n" subfield may be used instead. Fig.15 The "TID for LL MU EDCA on Link n" subfield in (a) and Fig.16 The "TID for LL EDCA on link n" subfield in (a) of FIG.

[0356] Fig.19 (b) The diagram is based on Fig.13 The TID-to-Link element illustrated in (b) applies the case where the "AC for MU EDCA on link n" subfield is replaced with the "TID for MU EDCA on link n" subfield.

[0357] The "AC for MU EDCA on link n" subfield has a length of 4 bits, and each bit may mean AC_BK, AC_BE, AC_VI, and AC_VO. In this case, if the value of each bit is set to 1, the MUEDCA parameter set can be applied to the corresponding AC.

[0358] The "AC for LL (MU) EDCA on Link n" subfield may be used instead. Fig.15 The "TID for LL MU EDCA on link n" subfield in (b) and Fig.17 The “TID for LL EDCA on link n” subfield in (b)

[0359] Fig.13 (b) MU EDCA mapping field, Fig.15 (b) LL MU EDCA mapping fields and Fig.17 (b) The LL EDCA Mapping field may have 18 octets, but Fig.18 The (a) MU EDCA Map field may have 10 octets.

[0360] Fig.19 (c) The diagram is based on Fig.13 The TID-to-Link element illustrated in (c) applies the case where the "Link for MU EDCA on AC_BK (AC_BE, AC_VI, or AC_VO)" subfield replaces the "Link for MU EDCA on TID n" subfield.

[0361] Here, the 'MU EDCA Indicator' subfield has a length of 4 bits, and each bit can mean AC_BK, AC_BE, AC_VI, AC_VO. At this time, if the value of each bit is set to 1, it means that the MU EDCA parameter set is applied to the corresponding AC.

[0362] The Link for LL (MU) EDCA on AC_BK (AC_BE, AC_VI, or AC_VO) subfield may be applied instead of Fig.15 The "Link for LL MU EDCA on TID n" subfield in (c) and Fig.17 The "Links for LL EDCA on TID n" subfield in (c) of FIG.

[0363] For example, when MU EDCA is applied to link 0 and link 15, it is assumed that the AC to which MU EDCA is applied in each link corresponds to AC_BK in link 0 and AC_BK and AC_BE in link 15. The value of the MU EDCA Presence field in the TID to Link Mapping Control field may be set to 1.

[0364] However, because in Fig.19 In (a) of FIG. 1 , the link ID is indicated in an array format, so the "Link ID for MU EDCA" subfield value can be set to "0000" and "1111". Fig.19 (b) indicates a link through a bitmap, so the "Link for MU EDCA Indicator" subfield value can be set to "1000000000000001". In order to indicate information about the AC to which MU EDCA is applied in each link, Fig.19 The "AC for MU EDCA on Link 0" subfield value of (a) and (b) can be set to "1000", and the "AC for MU EDCA on Link 15" subfield value can be set to "1100". Therefore, the length of the MU EDCA Map field can be Fig.19 (a) has a length of 2 octets, and Fig.19 The (b) has a length of 3 octets.

[0365] As another example of the present disclosure, ACs to which MU EDCA is applied are AC_BK and AC_BE, assuming that they operate on links 0, 1, 2, 13, 14, and 15.

[0366] because Fig.19 The 'MU EDCA Indicator' subfield value in (c) is set to '1100', so it can indicate that MU EDCA is applied to AC_BK and AC_BE.

[0367] In addition, there may be an "AC for MU EDCA Link" subfield corresponding to an AC with a value of 1. Fig.19 As illustrated in (c) of FIG. 1 , the “Link for MU EDCA on AC_BK” subfield and the “Link for MU EDCA on AC_BE” subfield may be located in the MU EDCA Map field in order after the “MU EDCA Indicator” subfield value.

[0368] exist Fig.19In case (c), the MU EDCA MAP field can have a total length of 5 octets. The "Links for MU EDCA on AC_BK" subfield value is set to "1110000000000111", so that AC_BK with MU EDCA applied can be indicated to operate on links 0, 1, 2, 13, 14, and 15.

[0369] By having the same value for other "Links for MU EDCA on AC_BE" subfields, it can be indicated that the AC with applied MU EDCA is to operate on links 0, 1, 2, 13, 14, 15.

[0370] exist Fig.19 In (c), the ACs to which MU EDCA is applied on links 0, 1, 2, 3, 13, 14, and 15 are illustrated as being the same, but the ACs to which MU EDCA is applied on each link may be different. For example, the ACs to which MU EDCA is applied on link 0 and link 1 may be set to AC_BK, and the TIDs to which MU EDCA is applied on link 3 may be set to AC_BK and AC_BE.

[0371] The above-mentioned embodiments are elements and features of the present disclosure combined in a predetermined form. Unless otherwise explicitly mentioned, each element or feature should be considered optional. Each element or feature can be implemented in a form that is not combined with other elements or features. In addition, the embodiments of the present disclosure may include combined partial elements and / or features. The order of the operations described in the embodiments of the present disclosure may be changed. Some elements or features of an embodiment may be included in other embodiments, or may be replaced by corresponding elements or features of other embodiments. It is clear that an embodiment may include a combined claim without an explicit dependency in the claim, or may be included as a new claim by modification after application.

[0372] It is clear to those skilled in the art that the present disclosure can be implemented in other specific forms within the scope of the essential features of the present disclosure. Therefore, the above detailed description should not be interpreted restrictively in every aspect, but should be considered as illustrative. The scope of the present invention should be determined by the reasonable interpretation of the attached claims, and all changes within the equivalent scope of the present disclosure are included in the scope of the present invention.

[0373] The scope of the present disclosure includes software or machine executable commands (e.g., operating systems, applications, firmware, programs, etc.) that perform operations in a device or computer according to the methods of various embodiments, and non-transitory computer-readable media that store such software or commands, etc. and can be executed in a device or computer. Commands that can be used to program a processing system that performs the features described in the present disclosure can be stored in a storage medium or a computer-readable storage medium, and the features described in the present disclosure can be implemented by using a computer program product that includes such a storage medium. The storage medium may include a high-speed random access memory, such as DRAM, SRAM, DDR RAM, or other random access solid-state storage devices, but is not limited thereto, and it may include non-volatile memory, such as one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid-state storage devices. The memory optionally includes one or more storage devices located away from the processor. The memory or alternatively, the non-volatile memory device in the memory includes a non-transitory computer-readable storage medium. The features described in this disclosure may be stored in any machine-readable medium to control the hardware of a processing system, and may be integrated into software and / or firmware that allows the processing system to interact with other mechanisms using the results from embodiments of the present disclosure. Such software or firmware may include, but is not limited to, application code, device drivers, operating systems, and execution environments / containers.

[0374] [Industrial Applicability]

[0375] The method proposed by the present disclosure is mainly described based on an example of being applied to an IEEE 802.11-based system and a 5G system, but can also be applied to various WLAN or wireless communication systems other than the IEEE 802.11-based system.

Claims

1. A method performed by a first station (STA) MLD (Multi-Link Device) in a wireless LAN system, the method comprising: sending a specific element including a multi-user (MU) enhanced distributed channel access (EDCA) mapping field to a second STA MLD or receiving the specific element from the second STA MLD; and Based on the specific element, performing MU EDCA operation on at least one link, The MU EDCA mapping field includes first information related to at least one link and second information related to at least one service identifier (TID) corresponding to the at least one link.

2. The method according to claim 1, wherein: The specific element is at least one of a TID-to-link element, an EDCA mapping element, or a LL (Low Latency) EDCA mapping element.

3. The method according to claim 2, wherein: At least one of the TID-to-link element, the EDCA mapping element, or the LL EDCA mapping element includes an EDCA control field or a LL EDCA control field, and The MU EDCA Control field or the LL EDCA Control field includes a first subfield indicating whether the MU EDCA Map field exists in at least one of the TID-to-link element, the EDCA Map element, or the LL EDCA Map element.

4. The method according to claim 1, wherein: The MU EDCA map field includes a second subfield, the second subfield includes an ID value of the at least one link or a bitmap indicating the at least one link, and The first information is indicated by the second subfield.

5. The method according to claim 4, wherein: The MU EDCA MAP field includes at least one third subfield indicating at least one TID associated with the MU EDCA operation corresponding to each of the at least one link, and The second information is indicated by the at least one third subfield.

6. The method according to claim 5, wherein: The number of the at least one third subfield is equal to the number of the at least one link.

7. The method according to claim 2, wherein: The TID is configured to the link element based on the MU EDCA parameter set element or the LL MU EDCA parameter set element.

8. The method according to claim 7, wherein: According to the TID to link element configured based on the LL MU EDCA parameter set element: The MU EDCA mapping field is associated with LL MU EDCA operation, At least one link performing the LL MU EDCA operation is indicated by the first information, and The at least one TID associated with the LL MU EDCA operation is indicated by the second information.

9. The method according to claim 7, wherein: The LL MU EDCA parameter set element includes a plurality of LL MU TID parameter record fields, and Each of the plurality of LL MU TID parameter record fields includes a LL MU EDCA timer subfield.

10. The method of claim 1, wherein: The MU EDCA MAP field includes third information related to at least one AC (Access Category) associated with the MU EDCA operation.

11. The method according to claim 10, wherein: The MU EDCA MAP field includes at least one fourth subfield indicating at least one AC corresponding to each of the at least one link, and The third information is indicated by the fourth subfield.

12. The method of claim 1, wherein: The first STA MLD is a non-access point (AP) STA MLD, and The second STA MLD is an AP MLD.

13. A first station (STA) MLD (Multi-Link Device) operating in a wireless LAN system, the first STA MLD comprising: at least one transceiver; as well as at least one processor coupled to the at least one transceiver, Wherein, the at least one processor is configured to: Sending, through the at least one transceiver, a specific element including a multi-user (MU) enhanced distributed channel access (EDCA) mapping field to a second STA MLD or receiving the specific element from the second STA MLD; and Based on the specific element, performing MU EDCA operation on at least one link, The MU EDCA mapping field includes first information related to at least one link and second information related to at least one service identifier (TID) corresponding to the at least one link.

14. A method performed by a second station (STA) MLD (Multi-Link Device) in a wireless LAN system, the method comprising: generating specific elements including a multi-user (MU) enhanced distributed channel access (EDCA) mapping field; as well as sending the specific element including the MU EDCA MAP field to a first STA MLD, The MU EDCA mapping field includes first information related to at least one link and second information related to at least one service identifier (TID) corresponding to the at least one link.

15. A second station (STA) MLD (Multi-Link Device) operating in a wireless LAN system, the second STA MLD comprising: at least one transceiver; as well as at least one processor coupled to the at least one transceiver, Wherein, the at least one processor is configured to: generating specific elements including a multi-user (MU) enhanced distributed channel access (EDCA) mapping field; and sending the specific element including the MU EDCA MAP field to a first STA MLD, The MU EDCA mapping field includes first information related to at least one link and second information related to at least one service identifier (TID) corresponding to the at least one link.

16. A processing device configured to control a first station (STA) MLD (Multi-Link Device) operating in a wireless LAN system, the processing device comprising: at least one processor; as well as at least one computer memory operatively connected to the at least one processor and storing instructions that, upon execution by the at least one processor, perform operations comprising: sending a specific element including a multi-user (MU) enhanced distributed channel access (EDCA) mapping field to a second STA MLD or receiving the specific element from the second STA MLD; and Based on the specific element, performing MU EDCA operation on at least one link, The MU EDCA mapping field includes first information related to at least one link and second information related to at least one service identifier (TID) corresponding to the at least one link.

17. At least one non-transitory computer-readable medium storing at least one instruction, in, The at least one instruction executable by the at least one processor controls a device operating in a wireless LAN system to: sending a specific element including a multi-user (MU) enhanced distributed channel access (EDCA) mapping field to a second STA MLD or receiving the specific element from the second STA MLD; and Based on the specific element, performing MU EDCA operation on at least one link, The MU EDCA mapping field includes first information related to at least one link and second information related to at least one service identifier (TID) corresponding to the at least one link.

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