Method and apparatus for transmitting / receiving traffic in wireless LAN system

Abstract

A method and apparatus for operating in a wireless LAN system are disclosed. According to one embodiment of the present disclosure, a method performed by a first station (STA) in a wireless LAN system comprises the steps of: receiving a physical layer protocol data unit (PPDU) including a first trigger frame from an access point (AP); and transmitting a first low latency traffic (LLT) and / or LLT information related to the first LLT to the AP based on the first trigger frame, where the first trigger frame may include i) first information indicating whether the first trigger frame is related to transmission of the first LLT or LLT information, and ii) second information related to a random access resource unit (RA-RU) for transmission of the first LLT or LLT information.

Description

Technical Field

[0001] This disclosure relates to methods and apparatus for transmitting and receiving services and service-related information in a wireless local area network (WLAN) system. Background Technology

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

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

[0004] Technical issues

[0005] The technical problem addressed in this disclosure relates to methods and apparatus for transmitting and receiving services in a wireless LAN system.

[0006] The technical problem of this disclosure relates to a method and apparatus for transmitting information for preemption operations related to low-latency services in a wireless LAN system.

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

[0008] Technical solution

[0009] According to one embodiment of this disclosure, a method performed by a first station (STA) in a wireless local area network (WLAN) system may include the following steps: receiving a physical layer protocol data unit (PPDU) including a first trigger frame from an access point (AP); and sending at least one of a first low latency service (LLT) or LLT information associated with the first LLT to the AP based on the first trigger frame, wherein the first trigger frame may include: i) first information indicating whether the first trigger frame is associated with the transmission of the first LLT or LLT information, and ii) second information associated with a random access resource element (RA-RU) for the transmission of the first LLT or LLT information.

[0010] According to another embodiment of this disclosure, a method performed by an access point (AP) in a wireless LAN system may include the following steps: sending a physical layer protocol data unit (PPDU) including a first trigger frame to a first station (STA); and receiving, based on the first trigger frame, at least one of a first low-latency service (LLT) or LLT information associated with the first LLT from the first STA among at least one STA, wherein the first trigger frame may include: i) first information indicating whether the first trigger frame is associated with the transmission of the first LLT or LLT information, and ii) second information associated with a random access resource element (RA-RU) for the transmission of the first LLT or LLT information.

[0011] Technical effect

[0012] According to various embodiments of this disclosure, methods and apparatus for transmitting and receiving services in a wireless LAN system can be provided.

[0013] The technical problem disclosed herein relates to a method and apparatus for transmitting information regarding preemption of low-latency services in a wireless LAN system.

[0014] The effects achievable by this disclosure are not limited to those described above, and those skilled in the art can clearly understand other effects not described herein through the following description. Attached Figure Description

[0015] The accompanying drawings, which are included as part of the detailed description of this disclosure, provide embodiments of the disclosure and, together with the detailed description, describe the technical features of the disclosure.

[0016] Figure 1 A configuration block diagram of a wireless communication device according to an embodiment of the present disclosure is illustrated.

[0017] Figure 2 This is a diagram illustrating an exemplary structure of a WLAN system to which this disclosure can be applied.

[0018] Figure 3This is a diagram used to illustrate the link establishment process that can be applied to this disclosure.

[0019] Figure 4 This is a diagram used to illustrate the backoff processing that can be applied to this disclosure.

[0020] Figure 5 This is a diagram illustrating the CSMA / CA-based frame transmission operation that can be applied to this disclosure.

[0021] Figure 6 This is a diagram illustrating an example of a frame structure that can be used in a WLAN system to which this disclosure may be applied.

[0022] Figure 7 This is a diagram illustrating an example of a PPDU as defined in the IEEE 802.11 standard of this disclosure.

[0023] Figure 8 This is a diagram illustrating an exemplary format of the trigger frame to which the present disclosure may be applied.

[0024] Figure 9 This is a diagram illustrating issues related to LLT transmission in DL (downlink) TXOP.

[0025] Figure 10 This is a diagram illustrating issues related to LLT transmission in UL (uplink) TXOP.

[0026] Figure 11 This is a flowchart illustrating the operation of the first STA according to an embodiment of the present disclosure.

[0027] Figure 12 This is a flowchart illustrating the operation of an AP according to an embodiment of the present disclosure.

[0028] Figure 13 This is a diagram illustrating a method by which a STA reports LLT information to an AP according to an embodiment of the present disclosure.

[0029] Figure 14 This is a diagram illustrating a method for sending LLT information using an HT control field according to an embodiment of the present disclosure.

[0030] Figure 15 This is a diagram illustrating the configuration of a BA frame including LLT information according to an embodiment of the present disclosure.

[0031] Figure 16 This is a diagram illustrating a process for sending and receiving BA frames including LLT information according to an embodiment of the present disclosure.

[0032] Figure 17This is a diagram illustrating the configuration of an LLTBA frame according to an embodiment of the present disclosure and the process for sending and receiving LLTBA frames.

[0033] Figure 18 This is a diagram illustrating the configuration of an LLT BA frame for multiple TIDs according to an embodiment of the present disclosure, as well as the process for sending and receiving LLT BAs.

[0034] Figure 19 This is a diagram illustrating the configuration of an LLT BA frame for multiple TIDs according to an embodiment of the present disclosure, as well as the process for sending and receiving LLT BAs.

[0035] Figure 20 This is a diagram illustrating a method for sending LLT information using a MAC header according to an embodiment of the present disclosure.

[0036] Figure 21 This is a diagram illustrating the configuration of a TRS control field according to one embodiment of the present disclosure.

[0037] Figure 22 This is a diagram illustrating a method for triggering LLT information via a control field according to one embodiment of the present disclosure.

[0038] Figure 23 This is a diagram illustrating a method for triggering LLT information using an LLT polling trigger frame according to one embodiment of the present disclosure.

[0039] Figure 24 This is a diagram illustrating a method for triggering LLT information transmission via a user information field of a trigger frame, according to one embodiment of the present disclosure. Detailed Implementation

[0040] In the following, embodiments according to this disclosure will be described in detail with reference to the accompanying drawings. The detailed description disclosed with reference to the drawings is intended to describe exemplary embodiments of this disclosure and not to represent the only embodiments in which this disclosure can be implemented. The following detailed description includes specific details to provide a complete understanding of this disclosure. However, those skilled in the art will recognize that this disclosure can be implemented without these specific details.

[0041] In some cases, known structures and devices may be omitted, or they may be shown in block diagram form based on the core functions of each structure and device in order to prevent ambiguity in the concepts of this disclosure.

[0042] In this disclosure, when an element is referred to as “connected,” “combined,” or “linked” to another element, it can include both indirect and direct connections between the two elements. Furthermore, in this disclosure, the terms “comprising” or “having” specify the presence of the mentioned features, steps, operations, components, and / or elements, but do not exclude the presence or addition of one or more other features, stages, operations, components, elements, and / or groups thereof.

[0043] In this disclosure, terms such as "first" and "second" are used only to distinguish one element from another and are not used to limit the elements. Unless otherwise stated, they do not limit the order or importance of the elements. Therefore, within the scope of this disclosure, a first element in one embodiment may be referred to as a second element in another embodiment, and similarly, a second element in one embodiment may be referred to as a first element in another embodiment.

[0044] The terminology used in this disclosure is for the purpose of describing particular embodiments and not for limiting the claims. As used in the description of embodiments and the appended claims, the singular form is intended to include the plural form unless the context clearly indicates otherwise. The term “and / or” as used in this disclosure may refer to one of the associated enumerations, or is intended to refer to and include any and all possible combinations of two or more of them. Furthermore, unless otherwise stated, the “ / ” between words in this disclosure has the same meaning as “and / or”.

[0045] The examples disclosed herein can be applied to various wireless communication systems. For example, the examples disclosed herein can be applied to wireless LAN systems. For example, the examples disclosed herein can be applied to wireless LANs based on the IEEE 802.11a / g / n / ac / ax standards. Furthermore, the examples disclosed herein can be applied to wireless LANs based on the newly proposed IEEE 802.11be (or EHT) standard. The examples disclosed herein can be applied to wireless LANs based on the IEEE 802.11be version 2 standard, corresponding to the additional enhancements of the IEEE 802.11be version 1 standard. Additionally, the examples disclosed herein can be applied to wireless LANs based on next-generation standards following IEEE 802.11be. Furthermore, the examples disclosed herein can be applied to cellular wireless communication systems. For example, it can be applied to cellular wireless communication systems based on 3GPP standards using Long Term Evolution (LTE) technology and 5G New Radio (NR) technology.

[0046] The technical features that can be applied to examples of this disclosure will be described below.

[0047] Figure 1 A block diagram illustrating a wireless communication device according to an embodiment of the present disclosure is shown.

[0048] Figure 1 The first device 100 and the second device 200 illustrated herein can be replaced by various terms such as terminal, wireless device, wireless transceiver unit (WTRU), user equipment (UE), mobile station (MS), user terminal (UT), mobile subscriber station (MSS), mobile subscriber unit (MSU), subscriber station (SS), advanced mobile station (AMS), wireless terminal (WT), or simply user. Furthermore, the first device 100 and the second device 200 include access point (AP), base station (BS), fixed station, node B, base transceiver system (BTS), and network. It can be replaced by various terms such as artificial intelligence (AI) system, roadside unit (RSU), repeater, router, relay, and gateway.

[0049] Figure 1 The devices 100 and 200 illustrated herein may be referred to as stations (STAs). For example, Figure 1 The devices 100 and 200 illustrated herein may be referred to by various terms such as transmitting device, receiving device, transmitting STA, and receiving STA. For example, STA 110 and 200 may perform an access point (AP) role or a non-AP role. That is, in this disclosure, STA 110 and 200 may perform AP and / or non-AP functions. When STA 110 and 200 perform AP functions, they may simply be referred to as APs, and when STA 110 and 200 perform non-AP functions, they may simply be referred to as STAs. Alternatively, in this disclosure, AP may also be referred to as AP STA.

[0050] Reference Figure 1 The first device 100 and the second device 200 can transmit and receive radio signals via various wireless LAN technologies (e.g., IEEE 802.11 series). The first device 100 and the second device 200 may include interfaces for the Media Access Control (MAC) layer and Physical Layer (PHY) conforming to the IEEE 802.11 standard.

[0051] In addition to wireless LAN technology, the first device 100 and the second device 200 can also support various communication standards (e.g., 3GPP LTE series, 5G NR series standards, etc.). Furthermore, the devices disclosed herein can be implemented in various devices such as mobile phones, vehicles, personal computers, augmented reality (AR) devices, and virtual reality (VR) devices. Additionally, the STA of this specification can support various communication services such as voice calls, video calls, data communication, autonomous driving, machine-type communication (MTC), machine-to-machine (M2M), device-to-device (D2D), and IoT (Internet of Things).

[0052] The first device 100 may include one or more processors 102 and one or more memories 104, and may additionally include one or more transceivers 106 and / or one or more antennas 108. The processors 102 may control the memories 104 and / or the transceivers 106, and may be configured to implement the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure. For example, the processor 102 may transmit a wireless signal including the first information / signal via the transceivers 106 after generating first information / signal by processing information in the memories 104. Additionally, the processor 102 may receive a wireless signal including second information / signal via the transceivers 106, and then store information obtained through signal processing of the second information / signal in the memories 104. The memories 104 may be connected to the processor 102 and may store various information related to the operation of the processor 102. For example, the memories 104 may store software code including instructions for performing all or part of the processing controlled by the processor 102 or for performing the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure. Here, processor 102 and memory 104 may be part of a communication modem / circuit / chip designed to implement wireless LAN technology (e.g., IEEE 802.11 series). Transceiver 106 may be connected to processor 102 and may transmit and / or receive wireless signals via one or more antennas 108. Transceiver 106 may include a transmitter and / or a receiver. Transceiver 106 may be used with an RF (radio frequency) unit. In this disclosure, wireless device may refer to a communication modem / circuit / chip.

[0053] The second device 200 may include one or more processors 202 and one or more memories 204, and may additionally include one or more transceivers 206 and / or one or more antennas 208. The processors 202 may control the memories 204 and / or the transceivers 206, and may be configured to implement the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure. For example, the processors 202 may generate third information / signals by processing information in the memories 204, and then transmit a wireless signal including the third information / signals via the transceivers 206. Additionally, the processors 202 may receive wireless signals including fourth information / signals via the transceivers 206, and then store information obtained through signal processing of the fourth information / signals in the memories 204. The memories 204 may be connected to the processors 202 and may store various information related to the operation of the processors 202. For example, the memories 204 may store software code including instructions for performing all or part of the processing controlled by the processors 202 or for performing the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure. Here, processor 202 and memory 204 may be part of a communication modem / circuit / chip designed to implement wireless LAN technology (e.g., IEEE 802.11 series). Transceiver 206 may be connected to processor 202 and may transmit and / or receive wireless signals via one or more antennas 208. Transceiver 206 may include a transmitter and / or a receiver. Transceiver 206 may be used with an RF unit. In this disclosure, apparatus may refer to a communication modem / circuit / chip.

[0054] The hardware elements of devices 100 and 200 will be described in more detail below. Not limited thereto, one or more protocol layers may be implemented by one or more processors 102 and 202. For example, one or more processors 102 and 202 may implement one or more layers (e.g., functional layers such as PHY and MAC). One or more processors 102 and 202 may generate one or more PDUs (Protocol Data Units) and / or one or more SDUs (Service Data Units) according to the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts disclosed in this disclosure. One or more processors 102 and 202 may generate messages, control information, data, or information according to the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts disclosed in this disclosure. One or more processors 102 and 202 may generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the functions, processes, suggestions, and / or methods disclosed in this disclosure to provide them to one or more transceivers 106 and 206. One or more processors 102, 202 may receive signals (e.g., baseband signals) from one or more transceivers 106, 206 and obtain PDUs, SDUs, messages, control information, data or information, in accordance with the description, functions, processes, suggestions, methods and / or operation flowcharts included in this disclosure.

[0055] One or more processors 102, 202 may be referred to as controllers, microcontrollers, microprocessors, or microcomputers. One or more processors 102, 202 may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more ASICs (Application-Specific Integrated Circuits), one or more DSPs (Digital Signal Processors), one or more DSPDs (Digital Signal Processing Devices), one or more PLDs (Programmable Logic Devices), or one or more FPGAs (Field-Programmable Gate Arrays) may be included in one or more processors 102, 202. The descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure may be implemented using firmware or software, and the firmware or software may be implemented to include modules, processes, functions, etc. Firmware or software configured to execute the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure may be included in one or more processors 102, 202, or may be stored in one or more memories 104, 204 and driven by one or more processors 102, 202. The descriptions, functions, processes, suggestions, methods and / or operation flowcharts included in this disclosure can be implemented using firmware or software in the form of code, instructions and / or instruction sets.

[0056] One or more memories 104, 204 may be connected to one or more processors 102, 202 and may store data, signals, messages, information, programs, code, instructions, and / or commands in various forms. One or more memories 104, 204 may be configured with ROM, RAM, EPROM, flash memory, hard disk drive, registers, cache memory, computer-readable storage media, and / or combinations thereof. One or more memories 104, 204 may be located internally and / or externally to one or more processors 102, 202. Furthermore, one or more memories 104, 204 may be connected to one or more processors 102, 202 via various technologies such as wired or wireless connections.

[0057] One or more transceivers 106, 206 can transmit user data, control information, wireless signals / channels, etc., mentioned in the methods and / or operation flowcharts of this disclosure to one or more other devices. One or more transceivers 106, 206 can receive user data, control information, wireless signals / channels, etc., mentioned in the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure from one or more other devices. For example, one or more transceivers 106, 206 can be connected to one or more processors 102, 202 and can transmit and receive wireless signals. For example, one or more processors 102, 202 can control one or more transceivers 106, 206 to transmit user data, control information, or wireless signals to one or more other devices. Additionally, one or more processors 102, 202 can control one or more transceivers 106, 206 to receive user data, control information, or wireless signals from one or more other devices. Additionally, one or more transceivers 106, 206 may be connected to one or more antennas 108, 208, and one or more transceivers 106, 206 may be configured to transmit and receive user data, control information, wireless signals / channels, etc., mentioned in the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts included in this disclosure, via one or more antennas 108, 208. In this disclosure, one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers 106, 206 may convert received wireless signals / channels, etc., from RF band signals into baseband signals for processing using one or more processors 102, 202. One or more transceivers 106, 206 may convert user data, control information, wireless signals / channels, etc., processed using one or more processors 102, 202, from baseband signals into RF band signals. Therefore, one or more transceivers 106, 206 may include (analog) oscillators and / or filters.

[0058] For example, one of STAs 100 and 200 can perform the expected operation of an AP, and the other of STAs 100 and 200 can perform the expected operation of a non-AP STA. For example, Figure 1 Transceivers 106 and 206 can perform transmission and reception operations of signals (e.g., packet or physical layer protocol data units (PPDUs) conforming to IEEE 802.11a / b / g / n / ac / ax / be / bn). Additionally, in this disclosure, the various STAs can generate transmit / receive signals or perform data processing or calculations on the transmit / receive signals in advance by [the relevant entity / component]. Figure 1Processors 102 and 202 perform the following operations: For example, examples of generating transmit / receive signals or performing data processing or computations on transmit / receive signals in advance may include: 1) determining / acquiring / configuring / computing / decoding / encoding bit information of fields (signals (SIG), short training field (STF), long training field (LTF), data, etc.) included in the PPDU; 2) determining / configuring / acquiring time or frequency resources (e.g., subcarrier resources) for the fields (SIG, STF, LTF, data, etc.) included in the PPDU; 3) determining / configuring / acquiring specific sequences (e.g., pilot sequences, STF / LTF sequences, additional sequences applied to SIG) for the fields (SIG, STF, LTF, data, etc.) included in the PPDU action; 4) power control operations and / or power saving operations applied to the STA; 5) operations related to determining / acquiring / configuring / computing / decoding / encoding of the ACK signal. Additionally, in the example below, various information used by different STAs to determine / acquire / configure / calculate / decode / encode transmitted and received signals (e.g., information related to fields / subfields / control fields / parameters / power, etc.) can be stored. Figure 1 In memory 104 and 204.

[0059] In the following text, downlink (DL) can refer to a link used for communication from an AP STA to a non-AP STA, and DL PPDU / packets / signals can be sent and received via DL. In DL communication, the transmitter can be part of an AP STA, and the receiver can be part of a non-AP STA. Uplink (UL) can refer to a link used for communication from a non-AP STA to an AP STA, and UL PPDU / packets / signals can be sent and received via UL. In UL communication, the transmitter can be part of a non-AP STA, and the receiver can be part of an AP STA.

[0060] Figure 2 This is a diagram illustrating an exemplary structure of a wireless LAN system to which this disclosure can be applied.

[0061] A wireless LAN system can be structured by multiple components. These components interact to provide STA mobility support that is transparent to upper layers. The Basic Service Set (BSS) corresponds to the basic building blocks of a wireless LAN. Figure 2 An example is shown where there are two BSSs (BSS1 and BSS2), and two STAs included as members of each BSS (STA1 and STA2 are included in BSS1, and STA3 and STA4 are included in BSS2). Figure 2The ellipse representing the BSS can also be interpreted as representing the coverage area within the corresponding BSS where STAs maintain communication. This area can be called the Basic Service Area (BSA). When a STA moves outside the BSA, it cannot communicate directly with other STAs within the BSA.

[0062] If we do not consider Figure 2 The DS shown in the diagram represents the most basic BSS type in a wireless LAN: the Independent BSS (IBSS). For example, an IBSS can have a minimal form containing only two STAs. For instance, assuming other components are omitted, BSS1 containing only STA1 and STA2, or BSS2 containing only STA3 and STA4, can respectively correspond to representative examples of IBSS. This configuration is possible when STAs can communicate directly without an AP. Furthermore, in this type of wireless LAN, it is not pre-configured but can be configured as needed, and this can be called an ad-hoc network. Since an IBSS does not include an AP, there is no centralized management entity. That is, in an IBSS, STAs are managed in a distributed manner. In an IBSS, all STAs can consist of mobile STAs and are not allowed to access the Distributed System (DS), thus forming a self-contained network.

[0063] Membership of an STA in a BSS can be dynamically changed by opening or closing an STA, or by entering or leaving a BSS zone. To become a member of a BSS, an STA can join the BSS using a synchronization process. To access all services of the BSS infrastructure, an STA must be associated with the BSS. This association can be dynamically established and may include the use of Distributed System Services (DSS).

[0064] Direct STA-to-STA distance in a wireless LAN may be limited by PHY performance. In some cases, this distance limitation may be sufficient, but in others, longer distances between STAs may be required for communication. Distributed systems (DS) can be configured to support extended coverage.

[0065] DS refers to the structure of BSS interconnection. Specifically, such as... Figure 2As shown, a BSS can exist as an extension of a network composed of multiple BSSs. A DS is a logical concept and can be specified through the characteristics of the Distributed System Medium (DSM). At this point, the Wireless Medium (WM) and the DSM can be logically separated. Each logical medium is used for a different purpose and by different components. These media are not limited to being the same, nor are they limited to being different. In this way, the flexibility of a wireless LAN architecture (DS architecture or other network architectures) can be interpreted as multiple media being logically different. That is, a wireless LAN architecture can be implemented in various ways, and the corresponding wireless LAN architecture can be independently specified by the physical characteristics of each implementation.

[0066] The DS can support mobile devices by providing seamless integration of multiple BSSs and offering the logical services necessary for addressing to the destination. Additionally, the DS may include a component called a portal, which acts as a bridge between the wireless LAN and other networks, such as IEEE 802.X.

[0067] AP enables access to DS via WM for associated non-AP STAs, and refers to entities that also have STA functionality. Data movement between BSS and DS can be performed through AP. For example, Figure 2 STA2 and STA3, shown in the diagram, have the functionality of STAs and provide the ability for associated non-AP STAs (STA1 and STA4) to access the DS. Furthermore, since all APs essentially correspond to STAs, all APs are addressable entities. The address used by an AP for communication on the WM is not necessarily the same as the address used by the AP for communication on the DSM. A BSS consisting of APs and one or more STAs can be referred to as an infrastructure BSS.

[0068] Data sent from one of the STAs associated with the AP to the corresponding STA address of the AP can always be received on an uncontrolled port and can be processed by the IEEE 802.1X port access entity. Alternatively, when the controlled port is authenticated, the transmitted data (or frames) can be delivered to the DS.

[0069] In addition to the DS structure described above, Extended Service Sets (ESS) can also be configured to provide wide coverage.

[0070] An ESS (Service Set Identity) refers to a network of arbitrary size and complexity consisting of DS (Service Controller) and BSS (Service Set Service). An ESS can correspond to a set of BSSs connected to a DS. However, an ESS does not include the DS. An ESS network is characterized as an IBSS (Integrated Service Set Service) within the Logical Link Control (LLC) layer. STAs included in an ESS can communicate with each other, and a moving STA can transparently move from one BSS to another (within the same ESS) to the LLC. APs included in an ESS can have the same Service Set Identity (SSID). The SSID is distinguished from the BSSID, which serves as the identifier for the BSS.

[0071] Wireless LAN systems make no assumptions about the relative physical locations of BSSs, and all of the following forms are possible: BSSs can partially overlap, a form commonly used to provide continuous coverage. Additionally, BSSs may not be physically connected, and logically, there is no limit to the distance between BSSs. Furthermore, BSSs can be physically located in the same location, which can be used to provide redundancy. Additionally, one (or more) IBSS or ESS networks can physically exist in the same space as one (or more) ESS networks. This can correspond to the form of ESS networks when an ad hoc network operates in a location where an ESS network exists, when physically overlapping wireless networks are configured by different organizations, or when two or more different access and security policies are required in the same location, etc.

[0072] Figure 3 This is a diagram used to illustrate the link establishment process that can be applied to this disclosure.

[0073] In order for a STA to establish a link with the network and send / receive data, it first discovers the network, performs authentication, establishes an association, and performs authentication processing for security. The link establishment process can also be called session initiation processing or session establishment processing. Furthermore, the discovery, authentication, association, and security establishment processes of the link establishment process can be collectively referred to as association processing.

[0074] In step S310, the STA can perform a network discovery operation. The network discovery operation may include a scanning operation by the STA. That is, in order for the STA to access a network, it needs to find networks it can participate in. The STA should identify compatible networks before participating in a wireless network, and the process of identifying networks existing in a specific area is called scanning.

[0075] Scanning schemes include active scanning and passive scanning. Figure 3An exemplary network discovery operation including active scanning processing is illustrated. In active scanning, the STA performing the scan sends a probe request frame to discover which APs are present around it as the channel moves and awaits a response. The responder sends a probe response frame as a response to the probe request frame to the STA that sent the probe request frame. Here, the responder may be the STA that last sent a beacon frame in the BSS of the channel being scanned. In the BSS, the AP becomes the responder because it sends a beacon frame, and in the IBSS, the STAs in the IBSS rotate to send beacon frames, so the responder is not constant. For example, an STA that sends a probe request frame on channel 1 and receives a probe response frame on channel 1 may store the BSS-related information included in the received probe response frame and may move to the next channel (e.g., channel 2) and perform a scan in the same manner (i.e., sending and receiving probe requests / responses on channel 2).

[0076] Although not in Figure 3 As shown, scanning can be performed passively. In passive scanning, the STA performing the scan waits for beacon frames while moving through the channel. Beacon frames are one of the management frames defined in IEEE 802.11 and are sent periodically to notify of the existence of a wireless network and allow the STA performing the scan to find and participate in the wireless network. In the BSS, the AP periodically sends beacon frames, and in the IBSS, the STA within the IBSS rotates to send beacon frames. When the STA performing the scan receives a beacon frame, it stores the BSS information included in the beacon frame and records the beacon frame information for each channel while moving to another channel. The STA receiving the beacon frame can store the BSS-related information included in the received beacon frame, move to the next channel, and perform scanning in the next channel in the same manner. Comparing active and passive scanning, active scanning has the advantages of less latency and less power consumption.

[0077] After the STA discovers the network, an authentication process can be performed in step S320. To clearly distinguish it from the security establishment operation in step S340, which will be described later, this authentication process can be referred to as the first authentication process.

[0078] The authentication process includes the following steps: the STA sends an authentication request frame to the AP, and in response, the AP sends an authentication response frame to the STA. The authentication frame used for the authentication request / response corresponds to the management frame.

[0079] An authentication frame includes the authentication algorithm number, authentication transaction sequence number, status code, challenge text, robust security network (RSN), and finite circular group. These correspond to some examples of information that can be included in the authentication request / response frame and can be replaced with other information, or additional information may be included.

[0080] A STA can send an authentication request frame to an AP. The AP can determine whether to allow the corresponding STA's authentication based on the information included in the received authentication request frame. The AP can then provide the STA with the authentication processing result via an authentication response frame.

[0081] After the STA is successfully authenticated, the association process can be performed in step S330. The association process includes the following steps: the STA sends an association request frame to the AP, and in response, the AP sends an association response frame to the STA.

[0082] For example, an association request frame may include information related to various capabilities, beacon listening intervals, service set identifiers (SSIDs), supported rates, supported channels, RSNs, mobile domains, supported operation classes, service indication mapping broadcast requests (TIM broadcast requests), interoperability capabilities, etc. Similarly, an association response frame may include information related to various capabilities, status codes, association IDs (AIDs), supported rates, enhanced distributed channel access (EDCA) parameter sets, received channel power indicators (RCPIs), received signal-to-noise ratio indicators (RSNIs), mobile domains, timeout intervals (e.g., association recovery time), overlapping BSS scan parameters, TIM broadcast responses, quality of service (QoS) mappings, etc. These correspond to some examples of information that can be included in association request / response frames and may be replaced with other information, or additional information may be included.

[0083] After the STA successfully associates with the network, a security establishment process can be performed in step S340. The security establishment process in step S340 can be referred to as the authentication process via a Robust Secure Network Association (RSNA) request / response, the authentication process in step S320 is referred to as the first authentication process, and the security establishment process in step S340 can also be simply referred to as the authentication process.

[0084] The secure establishment process in step S340 may include, for example, the process of establishing a private key using a four-way handshake via Extensible Authentication Protocol (EAPOL) frames over the LAN. Alternatively, the secure establishment process may be performed according to a security scheme not defined in the IEEE 802.11 standard.

[0085] Figure 4 This is a diagram used to illustrate the backoff processing that can be applied to this disclosure.

[0086] In wireless LAN systems, the basic access mechanism for Media Access Control (MAC) is Carrier Sensing Multiple Access with Collision Avoidance (CSMA / CA). Also known as the Distributed Coordination Function (DCF) of IEEE 802.11 MAC, CSMA / CA essentially employs a "listen-before-talk" access mechanism. Under this type of access mechanism, before commencing transmission, the AP and / or STA can perform explicit channel assessment (CCA) of the sensing radio channel or medium during a predetermined time interval (e.g., the DCF inter-frame interval (DIFS)). As a result of the sensing, if it is determined that the medium is idle, frame transmission begins via the corresponding medium. Conversely, if the medium is detected to be occupied or busy, the corresponding AP and / or STA does not begin its own transmission and can set a delay period for medium access (e.g., a random backoff period) and attempt frame transmission after waiting. By applying a random backoff period, collisions can be minimized because multiple STAs are expected to attempt frame transmission after waiting for different time periods.

[0087] In addition, the IEEE 802.11 MAC protocol provides a Hybrid Coordination Function (HCF). HCF is based on DCF and Point Coordination Function (PCF). PCF is a polling-based synchronous access method, meaning that all receiving APs and / or STAs periodically poll to receive data frames. Furthermore, HCF includes Enhanced Distributed Channel Access (EDCA) and HCF Control Channel Access (HCCA). EDCA is a contention-based access method that provides data frames to multiple users, while HCCA uses a non-contention-based channel access method that utilizes a polling mechanism. Additionally, HCF includes a media access mechanism for improving the QoS (Quality of Service) of wireless LANs and can transmit QoS data during contention periods (CP) and contention-free periods (CFP).

[0088] Reference Figure 4 This section describes the operation based on a random backoff period. When an occupied / busy medium becomes idle, multiple STAs can attempt to transmit data (or frames). As a method to minimize collisions, each STA can individually select a random backoff count and attempt to transmit after waiting for the corresponding time slot. The random backoff count has a pseudo-random integer value and can be determined as one of the values ​​ranging from 0 to CW. Here, CW is the contention window parameter value. The CW parameter is assigned an initial value of CWmin, but can take a value twice as large as in the event of transmission failure (e.g., when no ACK is received for the transmitted frame). When the CW parameter value reaches CWmax, data transmission can be attempted while maintaining the CWmax value until successful data transmission, and when successful, the CWmin value is reset. The values ​​of CW, CWmin, and CWmax are preferably set to 2.n -1 (n=0, 1, 2, ...).

[0089] When random backoff processing begins, the STA continuously monitors the medium during the backoff time slot countdown based on the determined backoff count value. When monitoring the medium for occupancy, it stops the countdown and waits, and restarts the remainder of the countdown when the medium becomes idle.

[0090] exist Figure 4 In the example, when the packet to be sent arrives at STA 3's MAC, STA 3 can send the frame immediately after confirming that the medium has been idle for up to DIFS. The remaining STAs monitor and wait for the medium to be occupied / busy. Meanwhile, the data to be sent can also occur in each of STA 1, STA 2, and STA 5, and when the medium is detected as idle, each STA waits for up to DIFS, and then performs a countdown for the backoff slot based on a random backoff count value chosen by each STA. Assume STA 2 chooses the minimum backoff count value, and STA 1 chooses the maximum backoff count value. That is, the example illustrates the case where STA 5's remaining backoff time is shorter than STA 1's remaining backoff time when STA 2 completes its backoff count and begins frame transmission. STA 1 and STA 5 temporarily stop the countdown and wait while STA 2 occupies the medium. When STA 2's occupancy ends and the medium becomes idle again, STA 1 and STA 5 wait for DIFS and restart the stopped backoff count. In other words, frame transmission can begin after a countdown for the remaining backoff slot based on the remaining backoff time. Since STA5 has a shorter remaining backoff time than STA1, STA5 begins frame transmission. Data to be transmitted can also occur in STA4 while STA2 is occupying the medium. From STA4's perspective, when the medium becomes idle, STA4 can wait for DIFS, then execute a countdown based on a random backoff count value selected by STA4, and begin transmitting frames. Figure 4 The example illustrates a scenario where the remaining backoff time of STA5 accidentally conflicts with the random backoff count value of STA4. In this case, a collision may occur between STA4 and STA5. When a collision occurs, neither STA4 nor STA5 receives an ACK, so data transmission fails. In this situation, STA4 and STA5 can double the CW value, select a random backoff count value, and begin a countdown. While the medium is occupied due to the transmissions of STA4 and STA5, STA1 waits; when the medium becomes idle, STA1 waits for DIFS, and then begins frame transmission after the remaining backoff time has elapsed.

[0091] As in Figure 4In the example, data frames are frames used to send data forwarded to higher layers and can be sent after a backoff performed after DIFS, starting from when the medium becomes idle. Additionally, management frames are frames used to exchange management information that has not been forwarded to higher layers and are sent after a backoff performed after an IFS such as DIFS or Point Coordination Function IFS (PIFS). Subtypes of management frames include beacons, association requests / responses, reassociation requests / responses, probe requests / responses, authentication requests / responses, etc. Control frames are frames used to control access to the medium. Subtypes of control frames include request-to-transmit (RTS), clear-to-transmit (CTS), acknowledgment (ACK), power-saving polling (PS-Poll), block ACK (BlockAck), block ACK request (BlockACKReq), empty data packet announcement (NDP announcement), and triggering, etc. If a control frame is not a response frame to the previous frame, it is sent after a backoff performed after DIFS; if it is a response frame to the previous frame, it is sent without a backoff performed after short IFS (SIFS). The type and subtype of a frame can be identified by the type field and subtype field in the Frame Control (FC) field.

[0092] The Quality of Service (QoS) ST can perform a backoff following the Arbitration IFS (AIFS) for the Access Class (AC) to which the frame belongs (i.e., AIFS where i is a value determined by the AC) before the frame can be transmitted. Here, the frame that can use AIFS can be a data frame, management frame, or control frame, rather than a response frame.

[0093] Figure 5 This is a diagram illustrating the CSMA / CA-based frame transmission operation that can be applied to this disclosure.

[0094] As mentioned above, in addition to physical carrier sensing of the medium directly sensed by the STA, the CSMA / CA mechanism also includes virtual carrier sensing. Virtual carrier sensing aims to compensate for problems such as hidden node issues that may occur during medium access. For virtual carrier sensing, the STA's MAC can use the Network Allocation Vector (NAV). The NAV is a value that indicates to other STAs the remaining time until the medium is available for current use or for STAs authorized to use the medium. Therefore, a value set to NAV corresponds to the period during which the STA sending the frame plans to use the medium, and during the corresponding period, STAs receiving the NAV value are prohibited from accessing the medium. For example, the NAV can be configured based on the value of the "Duration" field in the frame's MAC header.

[0095] exist Figure 5 In the example, assume that STA1 is intended to send data to STA2, and STA3 is in a position that allows it to eavesdrop on some or all of the frames being sent and received between STA1 and STA2.

[0096] To reduce the likelihood of transmission conflicts among multiple STAs in CSMA / CA-based frame transmission operations, a mechanism using RTS / CTS frames can be applied. Figure 5 In the example, when STA1 is transmitting, as a result of carrier sensing by STA3, it can be determined that the medium is in an idle state. That is, STA1 can correspond to a hidden node with respect to STA3. Alternatively, in Figure 5 In the example, it can be determined that while STA2 is transmitting, the carrier sensing result medium of STA3 is in an idle state. That is, STA2 can correspond to a hidden node with respect to STA3. By exchanging RTS / CTS frames before performing data transmission and reception between STA1 and STA2, STAs outside the transmission range of either STA1 or STA2, or STAs outside the carrier sensing range of transmissions from STA1 or STA3, can avoid attempting to occupy the channel during data transmission and reception between STA1 and STA2.

[0097] Specifically, STA1 can determine whether a channel is in use through carrier sensing. Regarding physical carrier sensing, STA1 can determine the channel occupancy / idle status based on the energy level or signal correlation detected in the channel. Alternatively, regarding virtual carrier sensing, STA1 can use a Network Allocation Vector (NAV) timer to determine the channel occupancy status.

[0098] When the channel is idle during DIFS, STA1 can send an RTS frame to STA2 after performing backoff. When STA2 receives the RTS frame, STA2 can send a CTS frame to STA1 after SIFS as a response to the RTS frame.

[0099] If STA3 cannot eavesdrop on CTS frames from STA2 but can eavesdrop on RTS frames from STA1, STA3 can use the duration information included in the RTS frame to set the NAV timer for the subsequent consecutive frame transmission period (e.g., SIFS+CTS frame+SIFS+data frame+SIFS+ACK frame). Alternatively, if STA3 can eavesdrop on CTS frames from STA2, STA3 can also use the duration information included in the CTS frame to set the NAV timer for the subsequent consecutive frame transmission period (e.g., SIFS+data frame+SIFS+ACK frame) even though STA3 cannot eavesdrop on RTS frames from STA1. That is, if STA3 can eavesdrop on one or more RTS frames or CTS frames from STA1 or STA2, STA3 can set the NAV accordingly. When STA3 receives a new frame before the NAV timer expires, STA3 can use the duration information included in the new frame to update the NAV timer. STA3 does not attempt channel access until the NAV timer expires.

[0100] When STA1 receives a CTS frame from STA2, STA1 can send a data frame to STA2 after SIFS, starting from the time point when the CTS frame reception is complete. When STA2 successfully receives the data frame, STA2 can send an ACK frame to STA1 after SIFS as a response to the data frame. When the NAV timer expires, STA3 can determine whether the channel is being used through carrier sensing. If STA3 determines that the channel is not being used by other terminals during the DIFS period after the NAV timer expires, STA3 can attempt channel access after the contention window (CW) for random backoff has expired.

[0101] Figure 6 This is a diagram illustrating an example of a frame structure that can be used in a WLAN system to which this disclosure may be applied.

[0102] Using instructions or primitives (meaning a set of instructions or parameters) from the MAC layer, the PHY layer can prepare the MAC PDU (MPDU) to be transmitted. For example, when the PHY layer receives a command from the MAC layer requesting the start of transmission, it switches to transmit mode, configures the information (e.g., data) provided by the MAC layer in the form of a frame, and transmits it. Additionally, when the PHY layer detects a valid preamble in a received frame, it monitors the preamble header and sends a command to the MAC layer notifying the PHY layer of the start of reception.

[0103] In this way, information transmission / reception in a wireless LAN system is performed in the form of frames, and for this purpose, the PHY layer Protocol Data Unit (PPDU) format is defined.

[0104] A basic PPDU can include a Short Training Field (STF), a Long Training Field (LTF), a Signal (SIG) field, and a Data field. The most basic PPDU format (e.g., Figure 7 The non-HT (High Throughput) fields shown can consist solely of a Traditional-STF (L-STF), Traditional-LTF (L-LTF), Traditional-SIG (L-SIG) field, and a data field. Additionally, depending on the PPDU format type (e.g., HT mixed format PPDU, HT green format PPDU, VHT (Very High Throughput) PPDU, etc.), additional (or different types) RL-SIG, U-SIG, non-traditional SIG fields, non-traditional STF, non-traditional LTF (i.e., xx-SIG, xx-STF, xx-LTF (e.g., xx is HT, VHT, HE, EHT, etc.)) can be included between the L-SIG field and the data field.

[0105] STF is a signal used for signal detection, automatic gain control (AGC), diversity selection, precise time synchronization, etc., while LTF is a signal used for channel estimation and frequency error estimation. STF and LTF can be referred to as signals used for synchronization and channel estimation in the OFDM physical layer.

[0106] The SIG field can include various information related to PPDU transmission and reception. For example, the L-SIG field consists of 24 bits and can include a 4-bit rate field, a 1-bit reserved bit, a 12-bit length field, a 1-bit parity field, and a 6-bit tail field. The RATE field can include information about the modulation and coding rate of the data. For example, the 12-bit length field can include information about the length or duration of the PPDU. For example, the value of the 12-bit length field can be determined based on the type of PPDU. For example, for non-HT, HT, VHT, or EHT PPDUs, the value of the length field can be determined to be a multiple of 3. For example, for HEPPDUs, the value of the length field can be determined to be a multiple of 3 + 1 or a multiple of 3 + 2.

[0107] The data field may include a service field, a physical layer service data unit (PSDU), and a PPDU tail bit, and may also include padding bits if necessary. Some bits of the service field can be used for synchronization of the descrambler at the receiver. The PSDU corresponds to the MAC PDU defined in the MAC layer and may include data generated / used in the upper layer. The PPDU tail bit can be used to return the encoder to a 0 state. Padding bits can be used to adjust the length of the data field by predetermined units.

[0108] MAC PDUs are defined according to various MAC frame formats, and a basic MAC frame consists of a MAC header, a frame body, and a Frame Check Sequence (FCS). MAC frames can be composed of MAC PDUs and transmitted / received via PSDUs in the data portion of the PPDU format.

[0109] The MAC header includes a frame control field, a duration / ID field, and an address field. The frame control field can include control information required for frame transmission / reception. The duration / ID field can be set to the time used to transmit the corresponding frame, etc. For details on the sequence control, QoS control, and HT control subfields of the MAC header, refer to the IEEE 802.11 standard document.

[0110] The Narrow Data PPDU (NDP) format refers to a PPDU format that does not include the data field. In other words, NDP is a frame format that includes the PPDU preamble of the general PPDU format (i.e., the L-STF, L-LTF, L-SIG fields and other non-traditional SIG, non-traditional STF, and non-traditional LTF (if present)) and does not include the remaining part (i.e., the data field).

[0111] Figure 7 This is a diagram illustrating an example of a PPDU as defined in the IEEE 802.11 standard of this disclosure.

[0112] Various types of PPDUs have been used in standards such as IEEE 802.11a / g / n / ac / ax. The basic PPDU format (IEEE 802.11a / g) includes L-LTF, L-STF, L-SIG, and a data field. The basic PPDU format can also be referred to as a non-HT PPDU format (such as...). Figure 7 (as shown in (a)).

[0113] Compared to the basic PPDU format, the HT PPDU format (IEEE 802.11n) additionally includes the HT-SIG, HT-STF, and HT-LFT fields. Figure 7 The HT PPDU format shown in (b) can be referred to as the HT hybrid format. Furthermore, an HT green format PPDU can be defined, and this corresponds to a format consisting of HT-GF-STF, HT-LTF1, HT-SIG, one or more HT-LTFs and data fields, excluding L-STF, L-LTF, and L-SIG (not shown).

[0114] Compared to the basic PPDU format, examples of the VHT PPDU format (IEEE 802.11ac) additionally include VHTSIG-A, VHT-STF, VHT-LTF, and VHT-SIG-B fields (such as...). Figure 7 (as shown in (c)).

[0115] Compared to the basic PPDU format, examples of the HE PPDU format (IEEE 802.11ax) additionally include repeated L-SIG (RL-SIG), HE-SIG-A, HE-SIG-B, HE-STF, HE-LTF, and Packet Extension (PE) fields (such as...). Figure 7 (as shown in (d)). Some fields can be excluded, or their lengths can vary depending on the detailed examples of the HE PPDU format. For example, the HE-SIG-B field is included in the HE PPDU format for multi-user (MU), but not in the HE PPDU format for single-user (SU). Furthermore, the HE-Trigger-Based (TB) PPDU format does not include HE-SIG-B, and the length of the HE-STF field can vary up to 8 μs. The Extended Range (HE ER) SU PPDU format does not include the HE-SIG-B field, and the length of the HE-SIG-A field can vary up to 16 μs. For example, RL-SIG can be configured to be the same as L-SIG. Based on the presence of RL-SIG, the receiving STA can determine whether the received PPDU is an HE PPDU or an EHT PPDU, which will be described later.

[0116] EHT PPDU format can include Figure 7 EHT MU (Multi-user) in (e) and Figure 7 The EHT TB (trigger-based) PPDU in (f). The EHT PPDU format is similar to the HE PPDU format in that it includes RL-SIG following L-SIG, but it can include U (generic)-SIG, EHT-SIG, EHT-STF and EHT-LTF following RL-SIG.

[0117] Figure 7 In (e), the EHT MU PPDU corresponds to a PPDU carrying one or more data (or PSDU) for one or more users. That is, the EHT MU PPDU can be used for both SU and MU transmissions. For example, the EHT MU PPDU can correspond to a PPDU for one or more receiving STAs.

[0118] Compared to EHT MU PPDU, Figure 7 In (f), the EHT-SIG is omitted from the EHT TB PPDU. The STA that receives the trigger for UL MU transmission (e.g., trigger frame or trigger response schedule (TRS)) can perform UL transmission based on the EHT TB PPDU format.

[0119] The L-STF, L-LTF, L-SIG, RL-SIG, U-SIG (general signal), and EHT-SIG fields can be encoded and modulated so that even conventional STAs can attempt demodulation and decoding, and can be mapped based on a determined subcarrier frequency interval (e.g., 312.5 kHz). These can be referred to as pre-EHT modulated fields. Next, the EHT-STF, EHT-LTF, data, and PE fields can be encoded and modulated for demodulation and decoding by an STA that has successfully decoded a non-conventional SIG (e.g., U-SIG and / or EHT-SIG) and obtained the information contained in that field, and can be mapped based on a determined subcarrier frequency interval (e.g., 78.125 kHz). These can be referred to as EHT modulated fields.

[0120] Similarly, in the HE PPDU format, the L-STF, L-LTF, L-SIG, RL-SIG, HE-SIG-A, and HE-SIG-B fields can be referred to as pre-HE modulation fields, and the HE-STF, HE-LTF, data, and PE fields can be referred to as HE modulation fields. Additionally, in the VHT PPDU format, the L-STF, L-LTF, L-SIG, and VHT-SIG-A fields can be referred to as non-VHT modulation fields, and the VHT STF, VHT-LTF, VHT-SIG-B, and data fields can be referred to as VHT modulation fields.

[0121] Included Figure 7 In the EHT PPDU format, U-SIG can be configured based on, for example, two symbols (e.g., two consecutive OFDM symbols). Each symbol used for U-SIG (e.g., an OFDM symbol) can have a duration of 4 μs, and U-SIG can have a total duration of 8 μs. Each symbol of U-SIG can be used to transmit 26 bits of information. For example, each symbol of U-SIG can be transmitted and received based on 52 data tones and 4 pilot tones.

[0122] U-SIGs can be constructed in 20 MHz units. For example, if an 80 MHz PPDU is constructed, U-SIGs can be replicated. That is, the same four U-SIGs can be included in an 80 MHz PPDU. PPDUs with bandwidths exceeding 80 MHz can include different U-SIGs.

[0123] For example, A uncoded bits can be sent via U-SIG. The first symbol of U-SIG (e.g., U-SIG-1 symbol) can send the first X bits of the total A bits, and the second symbol of U-SIG (e.g., U-SIG-2 symbol) can send the remaining Y bits of the total A bits. The A bits (e.g., 52 uncoded bits) can include a CRC field (e.g., a 4-bit field) and a tail field (e.g., a 6-bit field). For example, the tail field can be used to terminate the lattice structure of the convolutional decoder and can be set to 0.

[0124] Bit information sent via U-SIG can be divided into version-independent bits and version-dependent bits. For example, U-SIG can be included in... Figure 7 The new PPDU format (e.g., UHR PPDU format) not shown in the figure can be included in the format of the U-SIG field included in the EHTPPDU format and the format of the U-SIG field included in the UHR PPDU format. The version-independent bits can be the same, and some or all of the version-related bits can be different.

[0125] For example, the size of the version-independent bits in U-SIG can be fixed or variable. Version-independent bits can be assigned only to the U-SIG-1 symbol, or to both the U-SIG-1 and U-SIG-2 symbols. Version-independent and version-dependent bits can be referred to by various names, such as first control bit and second control bit.

[0126] For example, the version-independent bits of U-SIG may include a 3-bit Physical Layer Version Identifier (PHY Version Identifier), which can indicate the PHY version (e.g., EHT, UHR, etc.) of the transmitted / received PPDU. The version-independent bits of U-SIG may include a 1-bit UL / DL Flag field. The first value of the 1-bit UL / DL Flag field is related to UL communication, and the second value is related to DL communication. The version-independent bits of U-SIG may include information about the length of the Transmission Opportunity (TXOP) and information about the BSS color ID.

[0127] For example, the version-related bits of U-SIG may include information that directly or indirectly indicates the type of PPDU (e.g., SU PPDU, MU PPDU, TB PPDU, etc.).

[0128] Information required for PPDU transmission and reception can be included in the U-SIG. For example, the U-SIG may also include information about bandwidth, information about the MCS technique applied to non-traditional SIGs (e.g., EHT-SIG or UHR-SIG), information indicating whether DCM (dual-carrier modulation) techniques (e.g., techniques used to achieve effects similar to frequency diversity by reusing the same signal on two subcarriers) are applied to non-traditional SIGs, information about the number of symbols used for non-traditional SIGs, and information about whether non-traditional SIGs are generated across the entire frequency band.

[0129] Some of the information required for PPDU transmission and reception may be included in U-SIG and / or non-traditional SIG (e.g., EHT-SIG or UHR-SIG). For example, information about the type of non-traditional LTF / STF (e.g., EHT-LTF / EHT-STF or UHR-LTF / UHR-STF), the length of the non-traditional LTF and the CP (cyclic prefix) length, the GI (guard interval) applicable to the non-traditional LTF, the preamble punching information applicable to the PPDU, and the resource unit (RU) allocation may be included only in U-SIG, only in non-traditional SIG, or may be indicated by a combination of information included in U-SIG and information included in non-traditional SIG.

[0130] Preamble puncturing can represent the transmission of a PPDU where no signal is present in one or more frequency units within the bandwidth of the PPDU. For example, the size of the frequency unit (or the resolution of the preamble puncturing) can be defined as 20 MHz, 40 MHz, etc. For example, preamble puncturing can be applied to PPDU bandwidths of a predetermined size or larger.

[0131] exist Figure 7 In the examples, non-traditional SIGs such as HE-SIG-B and EHT-SIG can include control information for receiving STAs. Non-traditional SIGs can be transmitted on at least one symbol, and a symbol can have a length of 4 μs. Information regarding the number of symbols used for EHT-SIGs can be included in previous SIGs (e.g., HE-SIG-A, U-SIG, etc.).

[0132] Non-traditional SIGs such as HE-SIG-B and EHT-SIG can include both public and user-specific fields. These public and user-specific fields can be encoded separately.

[0133] In some cases, the common field can be omitted. For example, in compressed mode using non-OFDMA (Orthogonal Frequency Division Multiple Access), the common field can be omitted, and multiple STAs can receive PPDUs (e.g., the data field of the PPDU) through the same frequency band. In uncompressed mode using OFDMA, multiple users can receive PPDUs (e.g., the data field of the PPDU) through different frequency bands.

[0134] The number of user-specific fields can be determined based on the number of users. A user block field can include up to two user fields. Each user field can be associated with either a MU-MIMO allocation or a non-MU-MIMO allocation.

[0135] The common fields may include CRC bits and a tail bit, where the length of the CRC bits can be determined to be 4 bits, and the length of the tail bit can be determined to be 6 bits and set to 000000. The common fields may include RU allocation information. RU allocation information may include information about the locations of RUs assigned to multiple users (i.e., multiple receiving STAs).

[0136] An RU can include multiple subcarriers (or tones). RUs can be used when transmitting signals to multiple STAs based on OFDMA technology. Additionally, RUs can be defined even when transmitting signals to a single STA. Resources can be allocated in units of RUs for non-traditional STFs, non-traditional LTFs, and data fields.

[0137] The appropriate RU size can be defined based on the PPDU bandwidth. RUs can be defined the same or different for the applied PPDU format (e.g., HEPPDU, EHT PPDU, UHR PPDU, etc.). For example, in the case of an 80 MHz PPDU, the RU layout for HEPPDU and EHT PPDU can be different. The appropriate RU size, number and location of RUs, DC (direct current) subcarrier locations and numbers, empty subcarrier locations and numbers, guard subcarrier locations and numbers, etc., for each PPDU bandwidth can be referred to as the tone scheme. For example, a tone scheme for high bandwidth can be defined as multiple iterations of a low-bandwidth tone scheme.

[0138] RUs of various sizes can be defined as 26-tone RUs, 52-tone RUs, 106-tone RUs, 242-tone RUs, 484-tone RUs, 996-tone RUs, 2×996-tone RUs, 3×996-tone RUs, etc. MRUs (Multiple RUs) differ from multiple individual RUs and correspond to a group of subcarriers composed of multiple RUs. For example, an MRU can be defined as 52+26 tones, 106+26 tones, 484+242 tones, 996+484 tones, 996+484+242 tones, 2×996+484 tones, 3×996 tones, or 3×996+484 tones. Furthermore, the multiple RUs constituting an MRU can be consecutive or non-consecutive in the frequency domain.

[0139] The specific size of the RU can be reduced or expanded. Therefore, the specific size of each RU in this disclosure (i.e., the number of corresponding tones) is not limiting but illustrative. In addition, in this disclosure, the number of RUs can vary depending on the RU size within a predetermined bandwidth (e.g., 20 MHz, 40 MHz, 80 MHz, 160 MHz, 320 MHz...).

[0140] Figure 7 The names of each field in the PPDU format are exemplary, and the scope of this disclosure is not limited to these names. Furthermore, the examples in this disclosure can be applied to… Figure 7 The PPDU format shown and based on Figure 7 A new PPDU format that excludes some fields and / or adds some fields, based on the PPDU format.

[0141] Figure 8 This is a diagram illustrating an example format of the trigger frame that can be applied to this disclosure.

[0142] A trigger frame can allocate resources for the transmission of one or more TB PPDUs and request the transmission of TB PPDUs. The trigger frame may also include additional information required by the STA sending the TB PPDU in response. The trigger frame may include public information and user information list fields in the frame body.

[0143] The common info field is information typically used for the transmission of one or more TB PPDUs requested by a trigger frame, such as trigger type, UL length, presence or absence of subsequent trigger frames (e.g., more TFs), CS (channel sensing) request, UL BW (bandwidth), HE / EHT P160, special user information field flags, etc.

[0144] The 4-bit trigger type subfield can have values ​​from 0 to 15. Values ​​0, 1, 2, 3, 4, 5, 6, and 7 are defined to correspond to Basic, Beamforming Report Polling (BFRP), Multi-User Block Acknowledgment Request (MU-BAR), Multi-User Request Transmission (MU-RTS), Buffer Status Report Polling (BSRP), Multicast with Retry (GCR), MU-BAR, Bandwidth Query Report Polling (BQRP), and NDP Feedback Report Polling (NFRP), respectively. Values ​​8 through 15 are reserved.

[0145] In public information, the trigger-related public information subfields may include information that can be optionally included based on the trigger type.

[0146] Special user information fields can be included in the trigger frame. These fields do not include user-specific information, but rather extended public information not provided in the public information fields.

[0147] The user information list includes zero or more user information fields. Figure 8 An example of the EHT variant user information field format is shown.

[0148] The AID12 subfield essentially indicates that it is a user information field for a STA with the corresponding AID. Furthermore, if the AID12 field has a specific predetermined value, it can be used for other purposes, such as assigning a Random Access (RA)-RU or being configured as a special user information field. A special user information field is a user information field that does not include user-specific information but includes extended public information not provided in the public information field. For example, a special user information field can be identified by the AID12 value 2007, and the special user information field flag subfield within the public information field can indicate whether a special user information field is included.

[0149] The RU allocation subfield can indicate the size and location of the RU / MRU. For this purpose, the RU allocation subfield can be interpreted together with the PS160 (primary / secondary 160 MHz) subfield of the user information field and the UL BW subfield of the public information field.

[0150] HT control fields

[0151] The following will describe in more detail the references included in the references. Figure 6 The HT control field in the MAC header is described.

[0152] The HT control field can exist in the control wrapper frame, and it can also exist in the management frame, QoS empty, and QoS data determined by the +HTC subfield of the frame control field.

[0153] A STA that supports receiving control frame packets with an HT control field can process it as if it had already received a frame of a subtype of the frame packet. A HE STA may not send a control frame packet to another HE STA.

[0154] HT control fields can have the format shown in Table 1 below.

[0155] [Table 1]

[0156] As disclosed in Table 1, the HT control field can include three variants (e.g., HT variant, VHT variant, and HE variant). The variant format can be distinguished by the value of the first (B0) and second (B1) bits of the HT control field.

[0157] The HT variant HT control field may include HT control intermediate subfields, and the VHT variant HT control field may include VHT control intermediate subfields. The VHT control intermediate subfields may include MRQ subfields, MSI / STBC subfields, MFSI / GID-L subfields, MFB subfields, GID-H subfields, encoding type subfields, FB Tx type subfields, and unrequested MFB subfields.

[0158] HE variant HT control fields may include aggregated control subfields. A- control subfields may include control list subfields with variable length and zero or more padding subfields. Control lists may include one or more control subfields. Control subfields may include a 4-digit control ID subfield and a control information subfield with variable length.

[0159] The Control ID subfield indicates the type of information transmitted in the Control Message subfield. For each value in the non-reserved Control ID subfield, the length of the Control Message subfield can be fixed. The values ​​of the Control ID subfield and the associated length of the Control Message subfield can be defined as shown in Table 2 below.

[0160] [Table 2]

[0161] Information corresponding to control ID values ​​0 through 6 can be defined in the A-control subfield of the HE variant HT control field. Information corresponding to control ID values ​​7 through 9 can be newly defined information for EHT STA. Additionally, information corresponding to control ID value 10 (i.e., AAR) can correspond to control ID value 9. Furthermore, if a padding subfield exists in the A-control subfield of the HE variant HT control field, the padding subfield follows the last control subfield and can be set to a zero sequence, making the length of the A-control subfield carried in the HT control field 30 bits.

[0162] Information transmission process for low-latency services

[0163] In a basic wireless LAN system, a STA (e.g., a non-AP STA and / or an AP) can perform channel access operations to transmit frames containing traffic. For example, an AP and / or a non-AP STA can obtain a transmission opportunity (TXOP) via Enhanced Distributed Channel Access (EDCA) and transmit frames within the obtained TXOP. As another example, a non-AP STA can transmit frames in response to a trigger frame received from an AP.

[0164] In other words, when a specific service is entered / generated in the transmission queue of an STA, the STA must perform channel access to transmit that specific service, thereby occupying the channel and / or obtaining a TXOP (Transmission Optimization Point). Here, we assume that a service requiring significantly low latency (i.e., a low-latency service) is entered / generated in the STA's transmission queue. To enable the STA to transmit the low-latency service, competition for channel access with other STAs is unavoidable, and there is a problem that if other STAs have already obtained a TXOP, the fast transmission of the low-latency service is not guaranteed.

[0165] In describing this disclosure, services requiring low latency (e.g., services that must be successfully transmitted within X ms) are referred to as LLT (Low Latency Services).

[0166] Figure 9 This is a diagram used to explain issues related to LLT transmission in DL (downlink) TXOP.

[0167] Specifically, such as Figure 9 As shown, when the AP (i.e., the TXOP holder) acquires the TXOP via channel access (DL) and then performs a frame exchange with STA 1 (i.e., the TXOP responder), the LLT to be sent from the AP to STA 2 can arrive at time T_1. STA 2 can set NAV due to the AP's TXOP, or determine the channel state as busy due to the frame exchange between the AP and STA 1.

[0168] Therefore, STA 2 can send LLT after performing a backoff procedure again after AP's TXOP. In this case, AP's TXOP may be long, and there is a possibility that another STA can acquire the TXOP, depending on the contention outcome when STA 2 performs backoff after AP's TXOP. Therefore, STA 2's LLT transmission may be significantly delayed, and there is a possibility that LLT requirements may not be met.

[0169] Figure 10 This is a diagram used to explain issues related to LLT transmission in UL (uplink) TXOP.

[0170] Specifically, such as Figure 10 As shown, when STA 1 (i.e., the TXOP holder) acquires the (UL) TXOP through channel access and then performs a frame exchange with the AP (i.e., the TXOP responder), the LLT to be sent to STA 2 can arrive at the AP at time T_1. Since the AP is performing a frame exchange within STA 1's TXOP, it cannot send the LLT to STA 2. Therefore, the AP can perform a backoff procedure again after STA 1's TXOP and then send the LLT to STA 2.

[0171] Here, the TXOP of STA 1 can be long, and there is a possibility that another STA can acquire the TXOP, depending on the contention outcome when the AP performs backoff after STA 1's TXOP. Therefore, the LLT transmission of the AP may be significantly delayed, and there is a possibility that the LLT requirements may not be met.

[0172] For example, in reference Figure 9 and Figure 10 In the described example, when an LLT (i.e., an LLT with transmission-related requirements) that a STA needs to transmit quickly arrives, there is a possibility that the STA may be unable to meet the requirements and transmit the LLT due to the TXOP length already acquired by another STA or channel access delay caused by competition with other STAs. This disclosure describes a method for solving the above problem.

[0173] The names of the processes and / or parameters described in this disclosure may be changed, and STA may include non-AP STA or APSTA. Additionally, in describing this disclosure, RU (Resource Unit) may mean RU or M (Multiple) RU.

[0174] Figure 11 This is a flowchart illustrating the operation of a first STA according to one embodiment of the present disclosure. Figure 11 and Figure 12In this context, each of the first STA and the second STA can be implemented as a non-AP STA or an AP STA, and the AP STA can be replaced by another non-AP STA.

[0175] The first STA can receive a PPDU (S1110) including the first trigger frame from the access point (AP).

[0176] As an example of this disclosure, the PPDU may include QoS data to be sent to each of at least one of the first STAs. Additionally or alternatively, the PPDU may include a first trigger frame for triggering transmission of at least one of a first low-latency service (LLT) or LLT information associated with the first LLT.

[0177] For example, the trigger frame variant of the first trigger frame can be one of the basic trigger frame variant, the BSRP (Buffer Status Report Polling) trigger frame variant, or the LLT polling trigger frame variant (e.g., a trigger frame variant used to trigger LLT information / LLT transmission). That is, the basic trigger frame variant, the BSRP trigger frame variant, or the LLT polling trigger frame variant can be indicated by the trigger type subfield of the first trigger frame, but is not limited to this.

[0178] As an example of this disclosure, the first trigger frame may include: i) first information indicating whether the first trigger frame is related to the transmission of the first LLT or LLT information, and ii) second information related to the random access resource element (RA-RU) for the transmission of the first LLT or LLT information.

[0179] In other words, the first information (or a field that includes the first information) can indicate whether the first trigger frame is associated with the transmission of the first LLT or LLT information. The first information can be set in the AID (Association Identifier) ​​field or padding field included in the common information field of the first trigger frame or the user information field of the first STA of the first trigger frame (or / and the user information field or special user information field for LLT information / LLT, etc.).

[0180] For example, an AID12 field set to a specific value can correspond to the first information. That is, when the AID12 field is set to a specific value, this can mean that the first trigger frame is associated with the transmission of the first LLT or LLT information. As another example, a subfield indicating the first information can be included in a common information field or a padding field.

[0181] Alternatively or additionally, the second information may include RA-RU information indicating that the RU assigned to the first STA is an RA-RU. For example, the first trigger frame may include at least one user information field, and the at least one user information field may include a first user information field corresponding to the first STA. The first user information field may include an RU allocation field, and an RU may be allocated to the first user through the RU allocation field. In this case, the second information may indicate that the RU assigned to the first user is an RA-RU used to transmit the first LLT and / or LLT information.

[0182] The RA-RU information included in the second information can be indicated by the AID12 field included in the first user information field. For example, when the AID12 field value is set to one of 1 to 2007, 2044, and 2045, it can indicate that the RU assigned to the first user is an RA-RU for the transmission of the first LLT and / or LLT information.

[0183] The first STA may send at least one of the first LLT or LLT information related to the first LLT to the AP based on the first trigger frame (S1120).

[0184] Specifically, the first STA can perform the access procedure via UORA (Orthogonal Frequency Domain Multiple Access) on the RA-RU indicated by the first trigger frame. In addition, the first STA can send at least one of the first LLT or LLT information related to the first LLT to the AP via the RA-RU.

[0185] Alternatively or concurrently, if the PPDU includes QoS data for the first STA, the first STA may send the ACK (acknowledgment) information for the QoS data along with the first LLT and / or LLT information to the AP via the RA-RU.

[0186] Furthermore, the first STA can send at least one of a first LLT or LLT information to the AP through a TXOP (Transmission Opportunity) set by the AP. For example, the AP is the TXOP holder, and the first STA may or may not be a TXOP responder. That is, when the first LLT occurs within a TXOP, the first STA can send the first LLT and / or LLT information to the AP within the TXOP based on a PPDU.

[0187] As an example of this disclosure, LLT information may include at least one of the following: identification information of the first LLT, information about the time when the first LLT should complete the transmission, and information about the number of the first LLT.

[0188] As an example of this disclosure, assume that a first STA sends LLT information to an AP. Here, the first STA can receive a second trigger frame from the AP based on the LLT information. The second trigger frame may include information such as about the RU for the first LLT transmission. The first STA can send the first LLT to the AP through the RU for the first LLT transmission.

[0189] Both the PPDU reception operation of the first STA and the first LLT / LLT information operation of the first STA can be performed within the TXOP obtained by the AP.

[0190] Figure 11 The methods described in the examples can be derived from... Figure 1 The first device (100) is executed. For example, Figure 1 One or more processors (102) of the first device (100) can receive a first PPDU including a first trigger frame from the AP via one or more transceivers (106). One or more processors (102) can send at least one of a first LLT or LLT information associated with the first LLT to the AP via one or more transceivers (106) based on the first trigger frame.

[0191] Furthermore, one or more memories (104) of the first device (100) may store commands for execution when executed by one or more processors (102). Figure 11 The example or the method described in the example below.

[0192] Figure 12 This is a flowchart describing the operation of an AP according to one embodiment of the present disclosure.

[0193] The AP can send a PPDU (S1210) including a first trigger frame to at least one STA.

[0194] An AP can acquire a TXOP by exchanging CTS / RTS frames with at least one STA. Within the TXOP, the AP can send PPDUs to at least one STA. For example, the AP can send a first trigger frame to at least one STA via a broadcast RU, and can send QoS data via the RU assigned to each STA. (See reference...) Figure 11 The configuration of the first trigger frame is described, so repeated descriptions will be omitted.

[0195] The AP can receive at least one of the first LLT or LLT information related to the first LLT from the first STA among at least one STA based on the first trigger frame (S1220).

[0196] The AP can receive a first LLT and / or LLT information from the first STA via the RA-RU within the TXOP based on a first trigger frame. For example, upon receiving the LLT information, the AP can decode the information about the first LLT that the first STA intends to transmit. The AP can then send a second trigger frame to the first STA based on the information about the first LLT. The AP can then receive the first LLT from the first STA within the TXOP based on the second trigger frame.

[0197] In other words, both the AP's PPDU transmission operation and the AP's first LLT reception operation can be performed within the TXOP acquired by the AP.

[0198] Figure 12 The methods described in the examples can be derived from... Figure 1 The second device (200) is executed. For example, Figure 1 One or more processors (202) of the second device (200) can receive a PPDU including a first trigger frame from at least one STA via one or more transceivers (206). One or more processors (202) can receive at least one of a first LLT or LLT information associated with the first LLT from a first STA among at least one STA via one or more transceivers (206) based on the first trigger frame.

[0199] Furthermore, one or more memories (204) of the second device (200) may store commands for execution when carried out by one or more processors (202). Figure 12 The example or the method described in the example below.

[0200] The following section describes in detail the methods used to send information to preempt low-latency services.

[0201] Implementation Method 1

[0202] Implementation method 1 relates to a process for reporting LLT information.

[0203] Figure 13 This is a diagram illustrating a method by which a STA reports LLT information to an AP according to an embodiment of this disclosure. Figure 13 In this context, "LLT TX Request" means that an LLT has occurred that the STA must send quickly. For example, "LLT TX Request" could mean that an LLT has already been entered / occurred in the STA, or that an LLT must be sent quickly upon request.

[0204] here, Figure 13 The operations of AP and STA in the code can be replaced with the operations of STA and AP, respectively. That is to say, Figure 12The operation of the AP in the middle can be replaced by the operation of another STA, and Figure 13 The operations of STA can be replaced by the operations of AP.

[0205] like Figure 13 As shown, the AP can send trigger information to one or more STAs, enabling LLT information to be transmitted via PPDU. That is, the PPDU can include a trigger frame for requesting / triggering the transmission of LLT information. Additionally, the PPDU can include frames addressing one or more STAs (e.g., QoS data frames, etc.).

[0206] A STA that receives a PPDU / frame that triggers LLT information can send a frame / PPDU containing LLT information. A predefined time interval (e.g., SIFS, PIFS) can exist between the PPDU / frame that triggers LLT information and the frame containing LLT information.

[0207] An AP that receives LLT information from one or more STAs can send a frame (e.g., a trigger frame) that enables LLT transmission to one or more STAs. The one or more STAs that receive the frame can send a frame / PPDU containing the LLT to the AP.

[0208] Alternatively or concurrently, one or more STAs may send LLT information to the AP even if they have not received a PPDU / frame that triggered the LLT information. For example, in Figure 13 In this context, LLT information can be included in a frame / PPDU containing the LLT sent by a STA.

[0209] Implementation Method 1-1

[0210] Implementation method 1-1 involves one or more types of information included in the LLT information sent by the STA.

[0211] LLT information may include LLT presence information, LLT identification information, delay information, and / or the number of LLTs.

[0212] For example, LLT presence information can indicate that there is an LLT that a STA currently needs to send. Alternatively, LLT presence information can indicate whether a STA requests / expects to send an LLT within a particular STA's TXOP.

[0213] The LLT presence information can be supported by a field with 1 bit (e.g., the LLT presence information field). For example, when the value of the LLT presence information field is set to 1 (or 0), this can indicate the presence of an LLT that the STA should currently send or the STA requests / wants to send an LLT within the TXOP of a specific STA. For example, when the value of the LLT presence information field is set to 0 (or 1) or the field is reserved, this can indicate the absence of an LLT that the STA should currently send or the STA does not request / does not want to send an LLT within the TXOP of a specific STA.

[0214] As another example, the LLT identification information can include one or more ID information about the LLT to be sent. That is, the LLT identification information can include information about the LLT that needs to be sent. As an example, the LLT identification information can utilize the traffic identifier (TID). If the LLT corresponds to at least one of TID 0 to TID 7, the field indicating the LLT identification information can be set to 3 bits, and if the LLT corresponds to at least one of TID 8 to TID 15, the field indicating the LLT identification information can be set to 4 bits.

[0215] As another example of the present disclosure, a new LLT ID can be defined to indicate the identification information of the LLT. For example, the LLTID can be defined as an ID for distinguishing the LLTs for each TID. For example, the LLT can be classified as a 2-tuple <TID, LLID). For example, if LL ID 0 to LL ID 3 are assigned to TID 6, the LL service corresponding to TID 6 can be classified as <TID 6, LL ID 0>.

[0216] Additionally or alternatively, a bitmap can be defined to consider the LLTs for one or more IDs. That is, the LLT identification information can consist of a bitmap representing the LLT IDs. For example, if a total of X LLT IDs are defined, the bitmap can be configured to indicate up to X LLT IDs.

[0217] For example, the delay information can include information about when the LLT should be sent.

[0218] For example, the delay information can include the time from the time of sending the LLT information or the time of completing the transmission to the time when the LLT must be successfully sent. In this case, the delay information can indicate the time in μs.

[0219] Additionally or alternatively, the delay information can indicate the time point when the LLT should be successfully sent. For example, the delay information can indicate the time point when the LLT should be successfully sent based on absolute time, the timestamp (TSF).

[0220] Alternatively, it may be assumed that a latency time (LLT) exists for more than one ID. That is, if an LLT exists for each of the multiple IDs, the ID whose transmission should be completed earlier among the multiple IDs is identified, and the delay information may include the time that the transmission should be completed for that ID.

[0221] Alternatively or concurrently, if an LLT exists for each of the multiple IDs, the delay information may include the time that each of the multiple IDs should have completed the transmission.

[0222] For example, the amount of LLT information can include information about the number of LLTs to be sent. For example, the amount of LLT information can be configured in bytes.

[0223] Alternatively or concurrently, if an LLT exists for more than one ID, the number of LLT messages can indicate the number of LLT messages for all IDs. For example, the number of LLT messages could be the sum of the number of LLT messages for each of all IDs.

[0224] Alternatively or concurrently, if an LLT exists for more than one ID, the LLT count information can indicate the number of LLTs for each ID.

[0225] Alternatively, it may be assumed that a TID is used for an LLT. In this case, the LLT quantity information can indicate the number of LLTs for each AC (Access Class) to which the TID belongs. For example, if TID X and TID Y belong to AC 1, the LLT quantity information can indicate the sum of the LLTs for each of TID X and TID Y as the LLT quantity for AC 1.

[0226] Implementation Methods 1-2

[0227] Implementation methods 1-2 relate to a method for indicating / signaling LLT information. Specifically, LLT information can be indicated / signaled through the HT control field (Implementation method 1-2-1), the BA (block ack) frame (Implementation method 1-2-2), and the MAC header (Implementation method 1-2-3).

[0228] Implementation method 1-2-1

[0229] In one embodiment of this disclosure, LLT information can be sent and received via an HT control field (e.g., an A-control field). For example, LLT information can be included in a field of a new control type defined as an A-control field. This disclosure refers to the control field used for sending and receiving LLT information as an LLT information control field.

[0230] Figure 14 This relates to a method for sending LLT information using an HT control field (e.g., A-controlled LLT information control) according to one embodiment of the present disclosure. Figure 14 As shown, the AP can first obtain a TXOP via RTS / CTS switching, and then send a PPDU to STA 1. In this example, an A (aggregated)-MPDU including the QoS data frame on the PPDU can be sent to STA 1.

[0231] The PPDU may include information that triggers STA 1 to send LLT information. STA 1 receiving the PPDU can respond to / send an LLT information control field, including LLT information, to the AP using an A-MPDU. The LLT information control field may be included in at least one of a BA frame, an additional QoS data frame, and a QoS empty frame, and may be responded to / sent to the AP.

[0232] For example, if the BA frame includes an HT control field, the HT control field (or the BA frame) can be defined as a new control frame type, or the +HTC field value in the MAC header can be set to 1. Therefore, STA 1 can use the BA frame to simultaneously send LLT information and ACK information for the data frame to the AP.

[0233] For example, if the ACK policy for the MPDU in the PPDU sent by the AP is a policy that requires an immediate response to the BA frame (e.g., implicit BAR), then the BA frame (or BA information) may exist in the A-MPDU sent by STA 1. As another example, if the ACK policy for the MPDU in the PPDU sent by the AP is a policy that does not require an immediate response to the BA frame (e.g., ACK policy = BA), then the BA frame (or BA information) may not exist in the A-MPDU sent by STA 1.

[0234] An AP that receives a PPDU / frame including LLT information from STA 1 enables STA 1 to transmit the LLT by sending a trigger frame to STA 1. Here, STA 1 may include the LLT information in a response frame (e.g., an A-MPDU) to the trigger frame. As an example of this disclosure, STA 1 may send the LLT information to the AP along with a BA frame and / or a data frame.

[0235] Implementation Method 1-2-2

[0236] In one embodiment of this disclosure, it is assumed that LLT information is triggered simultaneously with the transmission of a (QoS) data frame to a specific STA. If an LLT exists on the specific STA, the specific STA can send the LLT information to the AP along with the BA frame. That is, the specific STA can include the LLT information in the BA frame instead of including the LLT information in a separate frame.

[0237] As an example of this disclosure, Figure 15 This is a diagram used to describe the configuration of BA frames that include LLT information.

[0238] like Figure 15 As shown in (a) and (b), LLT information can be set / indicated through reserved fields of the BA control field, regardless of the BA type of the BA frame. As another example, LLT information can be set on the tenth bit (B9) (i.e., no reserved memory), the eleventh bit (B10) (i.e., set memory on the tag), and the twelfth bit (B11) (i.e., manage ACK) of the BA control field.

[0239] For example, such as Figure 15 As shown in (a), the LLT Existence field can be set on the first (B0) of the BA control field.

[0240] As another example, such as Figure 15 As shown in (b), the LLT Presence field can be set in the first bit (B0) of the BA control field, and the LLT Identification information can be set in at least one of the sixth bit (B5) to the ninth bit (B10) of the BA control field. In this case, the LLT Identification information may include the TID for the LLT that needs to be transmitted, and the TID_INFO field may include information about the TID that the BA frame was sent (i.e., information confirming the success or failure of one or more MPDUs for a TID).

[0241] Figure 16 This is a diagram illustrating the process of sending and receiving BA frames including LLT information according to embodiments of the present disclosure.

[0242] The AP can first obtain a TXOP via CTS / RTS switching, and then send a PPDU to STA 1. For example, the PPDU may include an A-MPDU containing QoS data frames. STA 1 can respond to the PPDU by sending a BA frame containing LLT information to the AP.

[0243] The BA frame can include BA information for the ACK of the QoS data frame included in the A-MPDU. Additionally, LLT information can be included in the BA control field of the BA frame. For example, as... Figure 15As shown, LLT information can be included in the BA control field. Therefore, STA 1 can send LLT and ACK information for data frames to AP together with the BA frame.

[0244] An AP that receives a BA frame including LLT information from STA 1 can send a trigger frame to STA 1. STA 1 can then send an LLT to the AP based on the trigger frame. In this disclosure, LLT information can be included in the BA frame, regardless of the BA type.

[0245] Alternatively or concurrently, a new type of BA frame may be defined, or an existing type of BA frame may be used to include LLT information. In this disclosure, a BA frame defined as transmitting LLT information is referred to as an LLT BA frame.

[0246] In addition to the basic BA frame (e.g., a frame that includes ACK information for a data frame), the LLT BA frame may also include an LLT information field. An LLT information field is a field that contains one or more of the types of LLT information described above.

[0247] An LLT BA frame can satisfy at least one of the conditions described below.

[0248] - The BA type associated with a BA frame (or, BA control field) can be defined as a new type.

[0249] - The BA type in the BA control field can be a compressed BA frame variant.

[0250] - The BA information field of an LLT BA frame can be the same as the BA information field of a compressed BA frame variant.

[0251] - If the BA type of the LLT BA frame is a new type, the LLT information field can exist after the BA information field.

[0252] Alternatively or concurrently, the LLT information field may utilize the block ACK start sequence control subfield of the BA information field in at least one of the following ways.

[0253] - The segment number subfield of the block ACK start sequence control subfield can be set to a specific value. When the segment number subfield value is set to 4 bits (B3B2B1B0), the segment number subfield value of the block ACK start sequence control subfield can be set to "1111".

[0254] For example, as described above, the LLT information field can be included / placed on the BA frame based on a segment number subfield with a specific value set. For example, the LLT information field can be placed after a segment number subfield with a specific value set. Alternatively or additionally, the start sequence control subfield and / or block ACK bitmap subfield can be omitted based on a segment number subfield with a specific value set.

[0255] Figure 17 This is a diagram illustrating the configuration of an LLT BA frame according to one embodiment of the present disclosure and the process for sending and receiving LLT BA frames.

[0256] The AP can first obtain a TXOP via CTS / RTS switching, and then send a PPDU to STA 1. For example, the PPDU may include an A-MPDU containing QoS data frames. The PPDU may include information for STSA 1 to trigger LLT information. STA 1 may respond to the PPDU by sending a BA frame (i.e., an LLT BA frame) containing LLT information to the AP.

[0257] like Figure 17 As shown, an LLT BA frame may include ACK information for QoS data frames included in an A-MPDU, and the ACK information may be included in the BA information field. Additionally, a fragment number field set to a specific value may exist to indicate the presence of LLT information on the LLT BA frame. In this case, the fragment number field may follow the BA information field that includes the ACK information, but is not limited to this.

[0258] A fragment number field set to a specific value can indicate the presence of LLT information following the fragment number field. Therefore, STA 1 can use an LLT BA frame to send LLT information along with ACK information for the data frame to the AP simultaneously.

[0259] An AP that receives an LLT BA frame including LLT information from STA 1 can send a trigger frame to STA 1. STA 1 can then send an LLT to the AP based on the trigger frame. According to various embodiments of this disclosure, the LLT information can be included in the BA frame. For example, LLT information equal to or longer than the length of the BA information field can be included in the BA frame.

[0260] In one embodiment of this disclosure, the LLT BA frame may satisfy at least one of the conditions described below when it includes information related to multiple TIDs.

[0261] - The BA type in the BA control field can be defined as a new type.

[0262] - The BA type in the BA control field can be a multi-STA BA variant.

[0263] - The BA information field of the LLT BA frame is the same as that of the multi-STA BA frame, but the format of the per AID TID information subfield of the LLT of the LLT BA frame can be different.

[0264] Specifically, the AID TID information field of the AID TID star information subfield of the LLT BA frame can be applied in at least one of the following ways: - When a non-AP STA sends an LLT BA frame, the AID 11 subfield value of the AID TID-Specific Information subfield (for LLT) can be set to 0 or a specific value. For example, when a non-AP STA sends an LLT BA frame to the AP, the AID 11 subfield value can be set to a value other than 0 (e.g., 1 or 2008, etc.). Alternatively, the ACK type subfield and TID subfield of the AID TID-Specific Information subfield for LLT can be set to any value. Since non-AP STAs only send multi-STA BA frames to the AP, the AP can determine the presence of the LLT information field by using the specific AID value.

[0265] - When an AP sends a PPDU to a STA, the value of the AID 11 subfield of the AID TID-Specific Information subfield (for LLTs) can be set to the 11 LSB of the STA's AID. Alternatively or additionally, when an AP sends a PPDU to one or more non-AP STAs, the value of the AID 11 subfield of the AID TID-Specific Information subfield (for LLTs) can be set to a specific value (e.g., 0 or one of 2008 to 2044).

[0266] - The ACK type subfield of the AID TID-Specific Information Subfield (for LLT) can be set to a specific value (e.g., 0 or 1).

[0267] - AID TID - The TID subfield of the AID TID-Specific Information Subfield (for LLT) can be set to a specific value (e.g., one of 8 to 15), except when the ACK type subfield value is set to 1 and the TID subfield value is set to 15.

[0268] - The LLT information field can exist after the AID 11 subfield, ACK type subfield, and TID subfield that meet the above conditions. For example, if there is an AID TID information field that meets the above conditions (e.g., an AID TID information field that includes the AID 11 subfield, ACK type subfield, and TID subfield), then the LLT information field can exist on the AID TID-specific information subfield (for LLT).

[0269] - Alternatively or alternatively, if an AID TID information field that satisfies the above conditions exists (e.g., an AID TID information field that includes an AID11 subfield, an ACK type subfield, and a TID subfield), then the block ACK start sequence control field and / or block ACK bitmap field may not exist on the LLT BA frame.

[0270] Alternatively or additionally, if a specific value is set to match the conditions described above for the AID TID information field, the LLT information field may be present or included (on the LLT BA frame) instead of the Block ACK Start Sequence Control field and the Block ACK Bitmap field.

[0271] Alternatively or alternatively, if a specific value is set to match the conditions described above for the AID TID information fields, the LLT information field may be included instead of the Block ACK Start Sequence Control field and the Block ACK Bitmap field. Alternatively or alternatively, the size of the LLT information field may be the length of the LLT information itself. Alternatively or alternatively, the length of the Block ACK Start Sequence Control field and / or the length of the Block ACK Bitmap field may be included in the LLT information field.

[0272] Figure 18 This is a diagram used to explain the configuration of LLT BA frames for multiple TIDs and the transmission and reception process of LLTBA as an embodiment of this disclosure.

[0273] The AP can first obtain a TXOP via CTS / RTS switching, and then send a PPDU to STA 1. In this example, the PPDU may include a multi-TID A-MPDU, which includes QoS data frames for each of TID 1 and TID 2. The PPDU may include information to trigger STA 1 to send LLT information.

[0274] STA 1, receiving the corresponding PPDU, can respond to the AP using an LLT BA frame (i.e., a multi-STA BA frame including LLT information or a new type of LLT BA frame). For example... Figure 18 As shown, the corresponding LLT BA frame may include the AID TID information subfield of the ACK information for the QoS data frames included in the A-MPDU (i.e., for the QoS data frames of TID 1 and TID 2).

[0275] Additionally, the AID TID-Specific Information subfield, which includes LLT information, can use a specific ACK type (e.g., 0) and TID (e.g., 14) value to indicate the presence of LLT information following the AID TID-Specific Information subfield. Therefore, STA 1 can use an LLT BA frame to simultaneously send LLT information and ACK information for the data frame to the AP.

[0276] An AP that receives an LLT BA frame including LLT information from STA 1 can send a trigger frame to STA 1, and STA 1 can send an LLT to the AP based on the trigger frame. As mentioned above, the LLT BA frame can include LLT information. Furthermore, the LLT BA frame can include LLT information equal to or longer than the length of the BA information field, and can be applied to multiple TIDs.

[0277] Figure 19 This is a diagram illustrating the configuration of LLT BA frames for multiple TIDs and the LLTBA transmission and reception process according to embodiments of this disclosure. That is, Figure 19 Involving and Figure 18 Examples of different LLT BA frames for multiple TIDs.

[0278] The AP can first obtain a TXOP via CTS / RTS switching, and then send a PPDU to STA 1. In this example, the PPDU may include a multi-TID A-MPDU, which contains QoS data frames for each of TID 1 and TID 2. The PPDU may include information to trigger LLT information transmission for STA 1.

[0279] STA 1, receiving the corresponding PPDU, can respond to the AP using an LLT BA frame (i.e., a multi-STA BA frame including LLT information or a new type of LLT BA frame). For example... Figure 18 As shown, the corresponding LLT BA frame may include AID TID per AID TID information (per AID TID information) for the ACK information of the QoS data frames included in the A-MPDU (i.e., for the QoS data frames of TID 1 and TID 2).

[0280] Additionally, the per-AID TID information, which includes LLT information, can indicate that the LLT BA frame includes LLT information through a specific combination of AID, ACK type, and TID (i.e., the LLT information exists after the per-AID TID information). For example, as... Figure 18 As shown, when the combination of {specific AID, ACK type, TID} is set to {2020, 0, 0} or {0, 0, 8}, it can indicate that the LLT BA frame (or the per AID TID information subfield of the LLT included in the LLT BA frame) includes LLT information.

[0281] Alternatively or concurrently, the length of fields including LLT information can be indicated by the segment number field included in the LLT BA frame. For example, as Figure 19 As shown, if the fragment number field (e.g., 4 bits (B3B2B1B0)) is indicated / set to a specific value (e.g., "0110"), the LLT information can be included / set by utilizing the remaining fields of the total 6 octets (AID TID - Specific Information Subfield (for LLT)) excluding the fragment number field.

[0282] Alternatively, the start sequence control field can be retained. The names of the fragment number field, the start sequence control field, and the block ACK field can be changed.

[0283] Therefore, STA 1 can use an LL BA frame to simultaneously send LLT information and ACK information for the data frame to the AP. The AP receiving the LLT BA frame containing LLT information from STA 1 can send a trigger frame to STA 1, and STA 1 can send the LLT to the AP based on the trigger frame. As mentioned above, the LLT BA frame can include LLT information. Furthermore, the LLT BA frame can include LLT information that is the same length as or longer than the BA information field, and it can be applied to multiple TIDs.

[0284] Implementation Method 1-2-3

[0285] In one embodiment of this disclosure, fields in the MAC header can be used to send LLT information.

[0286] As an example of this disclosure, the STA may send a PPDU (e.g., an A-MPDU) to the AP that includes additional data fields. These additional data fields may include LLT presence information indicating the presence of LLT information. For example, if the STA sends a PPDU with an additional data field value set to 1, this could indicate the presence of LLT information to be sent by the STA to the AP.

[0287] Alternatively, the STA may send a PPDU (e.g., an A-MPDU) to the AP that includes a QoS control field. When bit 4 of the QoS control field is set to 0 or 1, bit 7 of the QoS control field may indicate the presence or absence of LLT information and / or the presence of LLT. In this case, bit 7 of the QoS control field may be set to 0 or 1. As described above, when bit 4 of the QoS control field is set to 0 or 1 and bit 7 of the QoS control field is set to indicate the presence or absence of LLT information, the LLT information may be set via at least one of bits 8 to 15 of the QoS control field.

[0288] Figure 20 This is a diagram illustrating a method for sending LLT information using a MAC header according to one embodiment of the present disclosure.

[0289] like Figure 20 As shown, the AP can first obtain a TXOP via RTS / CTS switching, and then send a PPDU to STA 1. In this example, an A-MPDU including the QoS data frame on the PPDU can be sent to STA 1.

[0290] The PPDU may include information that triggers STA 1 to send LLT information. STA 1, receiving the PPDU, can use the A-MPDU to send a QoS control field and / or additional data fields containing LLT information to the AP. In this case, the BA frame, QoS data frame, and / or QoS empty frame of the A-MPDU may include additional data fields and / or QoS control fields.

[0291] As an example of this disclosure, if the BA frame includes a QoS control field, the BA frame can be defined as a new control frame or a BA type. Therefore, STA 1 can use the BA frame to simultaneously send LLT information and ACK information for the data frame to the AP.

[0292] For example, if the ACK policy is set to require an immediate response to the BA frame (e.g., implicit BAR), the PPDU sent by the AP on the BA frame may include BA information for the MPDU (for QoS data). As another example, if the ACK policy is set to not require an immediate response to the BA frame (e.g., the ACK policy is set to BA), the PPDU sent by the AP on the BA frame may not include BA information for the MPDU (for QoS data).

[0293] An AP that receives an LLT BA frame containing LLT information from STA 1 can send a trigger frame to STA 1. STA 1 can include the LLT information in the MAC header of its response to the trigger frame (e.g., A-MPDU). In this disclosure, STA 1 can send LLT information and multiple frames (e.g., BA frames, data frames, etc.) to the AP simultaneously.

[0294] Implementation Method 2

[0295] Implementation 2 relates to the process of triggering LLT information and sending and receiving LLT information. That is, Implementation 2 specifies the LLT information triggering process and the LLT information sending and receiving process as in Implementation 1 and its sub-implementations. As mentioned above, the STA can be a non-AP STA or an AP.

[0296] In describing this disclosure, a STA (e.g., an AP, etc.) can acquire / initiate a TXOP by sending a frame / PPDU. Another STA (e.g., a non-AP STA) can receive one or more PPDUs from the STA (e.g., the AP) within the TXOP. The PPDUs include frames that trigger Low Latency Service (LLT) information. Here, one or more PPDUs may include frames addressing one or more STAs (e.g., QoS data frames).

[0297] Alternatively or concurrently, a predefined time (e.g., SIFS, PIFS) may exist between the PPDU / frame that triggers the LLT information and the frame containing the LLT information in response to the PPDU / frame.

[0298] A STA (e.g., an AP) that has received one or more frames / PPDUs containing LLT information can send a frame / PPDU that triggers LLT based on the LLT information to another STA (e.g., a non-AP STA).

[0299] An STA receiving one or more frames including LLT information can perform a frame detection operation to obtain LLT information for each STA. One or more STAs can then prepare to transmit PPDUs / frames that can trigger LLT using the obtained LLT information. Since the configuration of the LLT information has already been described in Implementation 1-1, redundant descriptions will be omitted. An STA receiving a PPDU / frame that triggers LLT can perform frame detection and prepare for LLT transmission via frame detection.

[0300] As an example of this disclosure, within a TXOP set by STA 1, STA 2 can send a frame containing LLT information to STA 1 and / or one or more other STAs. The LLT information can be sent to STA 1 via a response frame to the frame that triggered the LLT information or via another frame.

[0301] LLT information can be sent and received via at least one of the HT control field (e.g., A-control field), BA (block ACK) frame (e.g., BA control field of BA frame), or MAC header. For example, if LLT information is included in a BA frame, the BA frame can be defined as a new BA type.

[0302] Alternatively or alternatively, the field including LLT information may exist after or on the BA information field of the BA frame. Alternatively or alternatively, when the BA frame is a compressed BA, the segment number subfield of the block ACK start sequence control field may be set to a specific value to indicate that LLT information is included in the BA frame. Alternatively or alternatively, when the BA frame is a multi-STA BA frame, the AID TID information field of the per AID TID information subfield may be set to a specific value to indicate that LLT information is included in the BA frame.

[0303] Implementation Method 3

[0304] Implementation 3 relates to a process and related parameters for triggering LLT information. That is, as described in Implementation 1 (and / or a detailed implementation of Implementation 1) and Implementation 2, LLT information may be indicated by one or more frames, and therefore a process for triggering LLT information may be required. Triggering of LLT information may be performed via an HT control field and / or a trigger frame.

[0305] Implementation Method 3-1

[0306] In one embodiment of this disclosure, the triggering of LLT information can be performed via an HT control field. That is, the information used to send LLT information can be included in an HT control field (e.g., an A-control field).

[0307] For example, information used to trigger LLT messages can be sent and received via a Trigger Response Scheduler (TRS) control field, which is the control type of the A-control field. As another example, information used to trigger LLT messages can be sent and received via a new control field.

[0308] Alternatively or concurrently, LLT information may be triggered via the aforementioned control field, but LLT may be triggered. In describing this disclosure, the action of triggering LLT information may be replaced by the operation of triggering LLT.

[0309] Implementation method 3-1-1

[0310] In one embodiment of this disclosure, it can be achieved through Figure 21 The TRS control field shown in (a) is used to trigger LLT information. Figure 21 The TRS control field shown in (a) applies to STAs that have received the corresponding TRS control field; therefore, each STA must be able to decode the corresponding TRS control field in order to send LLT information. Thus, as... Figure 21 As shown in (b), the reserved field of the corresponding TRS control field can be used to indicate the triggering of LLT information.

[0311] For example, such as Figure 21 As shown in (b), the TRS control field (e.g., the 26th bit (B25) of the TRS control field) may include LLT information or information for LLT transmission (e.g., LLT information or information for triggering LLT transmission, etc.).

[0312] For example, the TRS control field may include a RU allocation subfield indicating LLT information or the RU used to send the LLT, and an LLT random access RU (RA-RU) subfield indicating the RU that can be accessed using UL OFDMA random access (UORA). As an example, such as Figure 21 As shown in (b), the LLT RA-RU subfield can be set on the 26th bit, but is not limited to this.

[0313] Implementation method 3-1-2

[0314] As an example of this disclosure, a new control field can be defined to trigger an LLT message or LLT. That is, the number of bits in the TRS control field may not be sufficient to include / set the information used to send the LLT message or LLT. Therefore, a control field with a new ID set for sending the LLT message or LLT can be defined (i.e., a new LLT TRS control field for sending the LLT message or LLT).

[0315] For example, such as Figure 21 As shown in (c), the LLT TRS control fields may include LLT TX subfields, RA-RU subfields, and / or associated subfields. The name of each of the LLT TX subfields, RA-RU subfields, and / or associated fields may be changed.

[0316] The LLT TX subfield can indicate that the RU indicated in the RU allocation subfield is the RU used to send LLT information or LLT.

[0317] The RA-RU subfield (e.g., 1 bit) can indicate that the RU indicated in the RU assignment subfield is a RU that can be accessed using UORA. For example, if the RA-RU subfield value is 1 (or 0), this could mean that the RU indicated by the RU assignment subfield is a RU that uses UORA.

[0318] The association subfield can indicate whether a frame can be sent by an associated STA or a non-associated STA in the RU indicated by the RU allocation subfield. For example, if the association subfield value is 1 (or 0), this can indicate that only associated STAs can access the RU indicated by the RU allocation subfield.

[0319] Figure 22This is a diagram used to explain a method for triggering LLT information via a control field according to one embodiment of this disclosure. That is, besides... Figure 13 In addition, Figure 22 It also involves methods for triggering LLT information through control fields.

[0320] The AP can first obtain a TXOP via RTS / CTS switching, and then send one or more frames to one or more STAs via PPDU. Here, the PPDU may include one or more A-MPDUs. The AP can use the A-MPDU to send a data frame to STA 1, and simultaneously indicate the RU (e.g., RU 1) to send the BA frame via the TRS control field. Alternatively, the AP can indicate the RU information (e.g., RU 2) for sending LLT information to at least one STA (which may include STA 1 and / or STA 2), and information indicating that RA-RU should be used, via a modified TRS control field or LLT TRS control field.

[0321] The aforementioned control fields can be sent to at least one STA via QoS empty frames or QoS data frames. The receiver address (RA) of the QoS empty frame or QoS data frame can be set to the MAC address or broadcast address specific to the STA.

[0322] In this disclosure, STA 2 can access RU 2 via UORA to send LLT information to AP. STA 1 can also compete for LLT information in RU 2 via UORA and / or send LLT information to AP via BA frames in RU 1.

[0323] For example, if the ACK policy for the MPDU in the PPDU sent by the AP is set to require an immediate response to the BA frame (e.g., HETP ACK), then the BA information can be included in the BA frame sent from STA 1. However, if the ACK policy is set to not require an immediate response to the BA frame (e.g., the ACK policy is set to BA), then the BA information for the MPDU in the PPDU sent by the AP in the BA frame may not be included.

[0324] Implementation Method 3-2

[0325] In one embodiment of this disclosure, a trigger frame can be used to allocate a Run-Unit (RU) for transmitting LLT information or an LLT. The trigger frame can allocate an RU for frame transmission, and a combination of the trigger frame and the RU allocation method can trigger the transmission of LLT information or an LLT.

[0326] Alternatively or concurrently, LLT information may be triggered via the aforementioned control field, but LLT may be triggered. In describing this disclosure, the operation of triggering LLT information may be replaced by the operation of triggering LLT.

[0327] Implementation method 3-2-1

[0328] In one embodiment of this disclosure, LLT information or a trigger frame capable of triggering LLT may be referred to as an LLT polling trigger frame, but is not limited thereto.

[0329] As an example of this disclosure, the LLT polling trigger frame can be set to a new trigger frame variant.

[0330] Alternatively or concurrently, the LLT polling trigger frame may utilize a basic or existing trigger frame variant format. In this case, reserved bits in the common information field of the LLT polling trigger (e.g., Figure 8 The reserved bits (e.g., EHT reserved bits, etc.) shown in the public information fields include / set LLT information or indicate LLT triggering bits / subfields.

[0331] For example, when sending a BSRP (Buffer Status Report Polling) trigger frame or a basic trigger frame, a bit / subfield indicating the trigger LLT information or LLT can be included / set in the common information field of the trigger frame. In this case, the STA receiving the trigger frame can send LLT information or LLT to the AP in response to the trigger frame, instead of a BSR.

[0332] An LLT polling trigger frame can assign a RU to a specific STA. Alternatively, an LLT polling trigger frame can assign one or more RA-RUs that a STA can access via UORA. The STA receiving the LLT polling trigger frame can send an LLT message or LLT (to AP) on the assigned RU and / or RA-RU after winning the contention.

[0333] Alternatively or additionally, the user information field for assigning an RU or RA-RU may include bits / fields / information indicating LLT information or LLT triggering. These bits / fields / information can be set via reserved bits in the user information field. This allows the purpose of the RU to be distinguished within a trigger frame.

[0334] Figure 23 This is a diagram used to explain a method of triggering LLT information using an LLT polling trigger frame according to an embodiment of the present disclosure.

[0335] The AP can first obtain a TXOP via RTS / CTS switching, and then send one or more frames to one or more STAs via PPDU. Here, the PPDU can include one or more MU PPDUs. For example, the AP can send an LLT polling trigger frame in RU 3, and can send an A-MPDU containing one or more QoS data frames to be sent to STA 1 in RU 4.

[0336] Here, RU 3 can be configured as a broadcast RU, so one or more STAs can receive and decode LLT polling trigger frames from the AP via RU 3. The LLT polling trigger frame can indicate that LLT information (or / and LLT) can be sent via RU 2, and RU 2 can be configured as an RA-RU via "AID=0". Therefore, in this example, STA 1, STA 2, and STA 3 can attempt to send LLT information (or / and LLT) via UORA in RU 2. Figure 23 This example illustrates how STA 2 accesses RU 2 via UORA to send LLT information.

[0337] For example, in RU 4, one or more QoS data frames can be sent / received to STA 1. Therefore, according to the ACK policy of the QoS data frames, STA 1 can send / respond to the AP using BA frames (for QoS data frames).

[0338] For example, if the ACK policy for the MPDU in the PPDU sent by the AP is set to a policy that requires an immediate response to the BA frame (e.g., HETP ACK), then the BA information can be included in the BA frame sent from STA 1. However, if the ACK policy is set to a policy that does not require an immediate response to the BA frame (e.g., the ACK policy is set to BA), then the BA information for the MPDU in the PPDU sent by the AP may not be included in the BA frame.

[0339] For example, if STA 1 can access RU 2, which is allocated in the LLT polling trigger frame, then STA 1 can send LLT information (or / and LLT) to the AP via RU 2. Alternatively or additionally, an RU (e.g., RU 1) can be allocated via the LLT polling trigger frame for the transmission of LLT information (or LLT) by STA 1.

[0340] Alternatively or alternatively, STA 3 may access the assigned RA-RU via LLT polling trigger frames to send LLT information (or / and LLT) to the AP.

[0341] For example, an AP that receives LLT information from STA 1, STA 2, and STA 3 can send trigger frames to STA 1, STA 2, and STA 3 to trigger the LLT. STA 1, STA 2, and STA 3 can then send the LLT back to the AP based on the received trigger frames.

[0342] Implementation method 3-2-2

[0343] In one embodiment of this disclosure, at least one field (including a reserved field) in the user information field of the trigger frame can be used to indicate that the trigger frame is a trigger frame for LLT information or an LLT trigger frame. In this case, the variant of the trigger frame is not limited to a specific variant.

[0344] As an example of this disclosure, if the AID12 field included in the user information field of the triggering frame is set to a specific value (e.g., 2044, 2047, etc.), this could mean that the RU assigned by the triggering frame is a RU used to send LLT information (or / and LLT). Here, the specific value can be set / defined to one or more of 1 to 2007 or a reserved value for a combination of STAs with a specific AID.

[0345] As an example of this disclosure, the RU indicated by the special AID12 field and the RU allocation subfield can be a RA-RU that can be accessed by multiple STAs via UORA.

[0346] Alternatively or additionally, a specific AID value (e.g., 2006, 2008, 2047) included in the trigger frame (e.g., in a user information field) may indicate that the trigger frame is a trigger frame for triggering LLT information or an LLT. As another example, a specific AID value and specific location (in a user information field) included in the trigger frame may indicate that the trigger frame is a trigger frame for triggering LLT information or an LLT.

[0347] Additionally, a specific AID value included in the trigger frame can indicate that the assigned RU (e.g., via a user information field) is to be used as an RA-RU. As another example, the trigger frame (or the user information field included therein) can include a field (or specific location) indicating that the assigned RU (e.g., via a RU allocation subfield) is to be used as an RA-RU.

[0348] Alternatively or additionally, information (or specific positioning) indicating that the trigger frame is used to trigger LLT information or the trigger frame of the LLT, or / and information (or specific positioning) indicating that the RU assigned by the trigger frame is used as the RA-RU, may be included in the padding bits of the trigger frame.

[0349] As an example of this disclosure, when the AID12 field indicates the AID of a particular STA, one or more reserved bits in the user information field of the trigger frame can indicate whether LLT information or LLT transmission is required in the allocated RU (via the trigger frame). That is, at least one bit included in the user information field of the trigger frame (e.g., reserved bits included in the user field, etc.) can indicate whether LLT information (or / and LLT) transmission is required or whether LLT information (or / and LLT) transmission is possible.

[0350] As an example of this disclosure, when an AID12 field with a specific set of values ​​(e.g., 0, 2045, etc.) indicates the allocation of one or more RA-RUs, one or more reserved bits in the user information field of the trigger frame can indicate whether LLT information (or LLT transmission) is required in the allocated RU (via the trigger frame). That is, at least one bit included in the user information field of the trigger frame (e.g., reserved bits included in the user field, etc.) can indicate whether LLT information (or / and LLT) transmission is required or whether LLT information (or / and LLT) transmission is possible.

[0351] Figure 24 This is a diagram illustrating a method for triggering the transmission of LLT information via a user information field of a trigger frame, according to one embodiment of the present disclosure.

[0352] The AP can first obtain a TXOP via RTS / CTS switching, and then send one or more frames to one or more STAs via PPDU. In this case, the PPDU can include one or more MU PPDUs. For example... Figure 24 As shown, the AP can send a basic trigger frame via RU 3 and can send an A-MPDU containing one or more QoS data frames to STA 1 via RU 4. As mentioned above, the basic trigger frame can be replaced by another variant of the trigger frame (e.g., a BSRP trigger frame).

[0353] RU 3 can be configured as a broadcast RU, and one or more STAs can receive / decode basic trigger frames from the AP via RU 3. Basic trigger frames allow LLT information (or / and LLT) to be sent via RU 2 (i.e., allow triggering LLT information (or / and LLT)). Additionally, an RU (e.g., RU 2) can be configured to send LLT information (or / and LLT) when the AID value is set to a specific value (e.g., 2006). One or more STAs can compete for RUs via UORA, and RUs can be configured as RA-RUs.

[0354] Alternatively, the AID value can be set to 0 or 2045, thereby allowing the RU to be configured as an RA-RU. Additionally, one or more reserved bits in the user information field of the trigger frame can indicate whether LLT information (or LLT) needs to be sent in the assigned RU.

[0355] Therefore, STA 1, STA 2, and STA 3 can attempt to send LLT information (or LLT) to RU 2 via UORA. As an example of this disclosure, such as Figure 24 As shown, STA 2 can access RU 2 via UORA to send LLT information (or LLT) to AP.

[0356] The AP can send one or more QoS data frames to STA 1 via RU 4. Therefore, STA 1 can send / respond to the AP with a BA frame for the QoS data frame according to the ACK policy of the QoS data frame.

[0357] For example, if the ACK policy for an MPDU sent by the AP is set to require an immediate response to a BA frame (e.g., HETP ACK), then the BA information can be included in the BA frame sent from STA 1. However, if the ACK policy is set to not require an immediate response to a BA frame (e.g., the ACK policy is set to BA), then the BA information for the MPDU may not be included in the PPDU sent by the AP in the BA frame. Alternatively, when sending BA information and LLT information (or LLT), the method of including the LLT information (or LLT) in the compressed BA frame or multi-STA BA frame as described above can be applied.

[0358] Alternatively or concurrently, if STA 1 has access to RU 2 assigned by the basic trigger frame, then STA 1 may send LLT information (or / and LLT) to AP via RU 2.

[0359] Alternatively or additionally, the basic trigger frame may allocate a RU (e.g., RU1) for transmitting LLT information for STA 1. In this case, whether LLT information (or / and LLT) transmission is required in the allocated RU (via the trigger frame) can be indicated via one or more reserved bits in the user information field for STA 1.

[0360] As an example of this disclosure, such as Figure 24As shown, STA 3 can access the RA-RU (e.g., RU 5) allocated by the basic trigger frame to send LLT information (or LLT) to the AP. The AP, which has received LLT information from STA 1 and STA 2, can allocate RU 6 and RU 7 to STA 1 and STA 2 via the basic trigger frame for LLT transmission of STA 1 and STA 2.

[0361] As an alternative or alternative to embodiments 3-2-1 and 3-2-2, one or more STAs may send LLT information (or / and LLT) in the preamble / PHY header in one or more ways as follows.

[0362] - A broadcast RU can be defined for sending LLT information (or / and LLT). Based on the STA ID field in the PHY header being set to a specific value (e.g., 2006), only one or more STAs performing LLT information (or / and LLT) transmissions can access the broadcast RU. For example, in Figure 23 and Figure 24 In this context, at least one STA associated with a specific STA ID value can utilize RU 3, which is assigned as a broadcast RU.

[0363] - A field that triggers the transmission of LLT information (or / and LLT) (e.g., whether LLT information (or / and LLT) transmission is required) can be included in the PHY header. For example, in Figure 23 and Figure 24 In this context, if a field is included in the PHY header of the PPDU and the field value is set to a specific value (e.g., 1), then only the STA that needs to send LLT information (or / and LLT) can access RU 3, which is assigned as a broadcast RU.

[0364] Implementation Method 4

[0365] Implementation 4 involves the operation of a STA (e.g., a non-AP STA or / and AP) that triggers LLT information or / and LLT.

[0366] In this disclosure, a STA may send LLT information and / or one or more PPDUs for triggering an LLT to one or more other STAs within a TXOP initiated / acquired by transmitting / receiving frames / PPDUs. As an example, one or more PPDUs may include LLT information and / or a trigger frame for triggering an LLT.

[0367] Alternatively or concurrently, the PPDU / frame used to trigger LLT information (or / and LLT) may include an HT control field (e.g., an A-control field), and the HT control field may include information to be sent LLT information (or / and LLT).

[0368] Alternatively or additionally, when using a TRS control field as a control type of A-control field, the TRS control field may include information indicating that the RU used to send LLT information (or / and LLT) is an RU accessible through UORA.

[0369] Alternatively or additionally, a new control type for the A-control field can be defined to trigger LLT information (or / and LLT). For example, the control field according to the new control type may include at least one subfield included in the combined subfield, RA-RU subfield, LLT TX subfield, and / or TRS control field. The configuration of each control field has been described in implementation 3-1-2, therefore, redundant descriptions will be omitted.

[0370] Alternatively or additionally, one or more PPDUs / frames that trigger LLT information may include a trigger frame that includes information for sending LLT information (or / and LLT). Variations of the trigger frame that include information for sending LLT information (or / and LLT) may be new trigger variations or existing trigger variations. As another example, the common information field of the trigger frame may include information indicating that LLT information (or / and LLT) has been triggered.

[0371] Alternatively or concurrently, a trigger frame can assign a RU to a specific STA, and one or more STAs can be assigned one or more RA-RUs accessible via UORA.

[0372] Alternatively or additionally, the AID12 field included in the user information field of the corresponding trigger frame may be set to a specific value that indicates that the RU assigned by (the corresponding trigger frame) is the RU used to send LLT information (or / and LLT). For example, the specific value may include 1 to 2007 or a reserved value for an associated STA with a specific AID.

[0373] Alternatively or additionally, if the allocation of one or more RA-RUs is indicated by setting the AID12 field to a specific value (e.g., 0 or 2045, etc.), the necessity or possibility of sending LLT information (or / and LLT) in the RU can be indicated via one or more reserved bits in the user information field of the trigger frame.

[0374] Alternatively or concurrently, the preamble / PHY header of one or more PPDU / frames that triggers the LLT information (or / and LLT) may include information that only one or more STAs can access to send the LLT information (or / and LLT), as described below.

[0375] - A broadcast RU can be defined for sending LLT information (or / and LLT). The STA ID field in the PHY header can be set to a specific value (e.g., 2006) so that only STAs that need to send LLT information (or / and LLT) can access the broadcast RU.

[0376] - Fields that trigger the transmission of LLT information (or / and LLT) (e.g., whether LLT information (or / and LLT) transmission is required, etc.) can be included in the PHY header.

[0377] Through the above implementation method, the TXOP holder can confirm LLT-related information by receiving LLT information from one or more STAs. Furthermore, through information exchange between the TXOP holder and the STAs requiring LLT transmission, LLTs can be sent efficiently as needed.

[0378] The above embodiments combine the elements and features of this disclosure in a predetermined form. Unless otherwise expressly stated, each element or feature should be considered optional. Each element or feature may be implemented without being combined with other elements or features. Furthermore, embodiments of this disclosure may include combinations of some elements and / or features. The order of operations described in embodiments of this disclosure may be changed. Some elements or features of one embodiment may be included in other embodiments, or may be replaced by corresponding elements or features of other embodiments. Obviously, embodiments may include claims that are not explicitly referenced in the claims, or may be included as new claims after the application has been amended.

[0379] It will be apparent to those skilled in the art that this disclosure may be implemented in other specific forms without departing from its essential characteristics. Therefore, the above detailed description should not be construed as restrictive in every respect, but rather as illustrative. The scope of this disclosure should be determined by a reasonable interpretation of the appended claims, and all variations within the equivalent scope of this disclosure are included within its scope.

[0380] The scope of this disclosure includes software or machine-executable commands (e.g., operating systems, applications, firmware, programs, etc.) that operate in a device or computer according to methods of various embodiments, as well as non-transitory computer-readable media that cause software or commands to be stored and executable in a device or computer. Commands that can be used to program a processing system to perform the features described in this disclosure can be stored in a storage medium or a computer-readable storage medium, and the features described in this disclosure can be implemented by using a computer program product including such a storage medium. The storage medium may include, but is not limited to, high-speed random access memory, such as DRAM, SRAM, DDR RAM, or other random access solid-state storage devices, and may include non-volatile memory, such as one or more disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid-state storage devices. The memory may optionally include one or more storage devices located remotely from the processor. The memory, or alternatively, the non-volatile memory devices in the memory include non-transitory computer-readable storage media. The features described in this disclosure can be stored in any machine-readable medium to control the hardware of a processing system and can be integrated into software and / or firmware that allows the processing system to interact with other mechanisms using the results of embodiments of this disclosure. Such software or firmware may include, but is not limited to, application code, device drivers, operating systems, and execution environments / containers.

[0381] Industrial applicability

[0382] The method proposed in this disclosure has been described in reference to examples applied to IEEE 802.11-based systems, but the method can also be applied to various wireless LAN or wireless communication systems other than IEEE 802.11-based systems.

Claims

1. A method performed by a first STA in a wireless local area network (WLAN) system, the method comprising the following steps: Receive Physical Layer Protocol Data Unit (PPDU) including the first trigger frame from the access point (AP); as well as Based on the first trigger frame, send at least one of a first low-latency service (LLT) or LLT information related to the first LLT to the AP. The first trigger frame includes: i) first information indicating whether the first trigger frame is related to the transmission of the first LLT or the LLT information, and ii) second information related to the random access resource unit (RA-RU) for the transmission of the first LLT or the LLT information.

2. The method according to claim 1, wherein, The first information is set in the associated identifier AID 12 field or fill field included in the public information field of the first trigger frame or the user information field of the first STA of the first trigger frame.

3. The method according to claim 1, wherein, The second information includes RA-RU information indicating that the RU assigned to the first STA is the RA-RU, and The RU-RU information is indicated by the AID12 field included in the first user information field of the first STA in the first trigger frame.

4. The method according to claim 3, wherein, The AID12 field is set to one of 1 to 2007, 2044, or 2045.

5. The method according to claim 1, wherein, The first STA performs access on the RA-RU via Orthogonal Frequency Domain Multiple Access (UORA), and The RA-RU sends at least one of the first LLT or LLT information related to the first LLT to the AP.

6. The method according to claim 1, wherein, The trigger frame variant of the first trigger frame is one of the basic trigger frame variant, the buffer status report polling (BSRP) trigger frame variant, or the LLT polling trigger frame variant.

7. The method according to claim 1, wherein, The PPDU includes Quality of Service (QoS) data, and The ACK information for the QoS data is sent to the AP along with at least one of the first LLT or the LLT information.

8. The method according to claim 1, wherein, The LLT information includes at least one of the following: identification information of the first LLT, information about the time when the first LLT should be sent, and information about the number of the first LLT.

9. The method according to claim 1, wherein, The first LLT is sent to the AP based on the LLT information sent to the AP via the RA-RU, and based on the second trigger frame received from the AP.

10. The method according to claim 1, wherein, Within a transmission opportunity (TXOP) set by the AP, at least one of the first LLT or the LLT information is sent to the AP via the RA-RU.

11. The method according to claim 1, wherein, The AP is the TXOP holder, and the first STA is the TXOP responder.

12. A first STA in a wireless local area network (WLAN) system, the first STA comprising: At least one transceiver; as well as At least one processor, said at least one processor being connected to said at least one transceiver, Wherein, the at least one processor is configured to: The at least one transceiver receives a Physical Layer Protocol Data Unit (PPDU) including a first trigger frame from the access point (AP); and Based on the first trigger frame, at least one of a first low-latency service (LLT) or LLT information related to the first LLT is sent to the AP via the at least one transceiver. The first trigger frame includes: i) first information indicating whether the first trigger frame is related to the transmission of the first LLT or the LLT information, and ii) second information related to the random access resource unit (RA-RU) for the transmission of the first LLT or the LLT information.

13. A method performed by an access point (AP) in a wireless LAN system, the method comprising the following steps: Send a Physical Layer Protocol Data Unit (PPDU) including the first trigger frame to the first STA; as well as Based on the first trigger frame, at least one of a first low-latency service (LLT) or LLT information related to the first LLT is received from the first STA among at least one STA. The first trigger frame includes: i) first information indicating whether the first trigger frame is related to the transmission of the first LLT or the LLT information, and ii) second information related to the random access resource unit (RA-RU) for the transmission of the first LLT or the LLT information.

14. An access point (AP) operating in a wireless LAN system, the AP comprising: At least one transceiver; as well as At least one processor, said at least one processor being connected to said at least one transceiver, Wherein, the at least one processor is configured to: The at least one transceiver sends a Physical Layer Protocol Data Unit (PPDU) including a first trigger frame to the first station (STA); and Based on the first trigger frame, at least one of a first low-latency service (LLT) or LLT information related to the first LLT is received from the first STA (at least one STA) via the at least one transceiver. The first trigger frame includes: i) first information indicating whether the first trigger frame is related to the transmission of the first LLT or the LLT information, and ii) second information related to the random access resource unit (RA-RU) for the transmission of the first LLT or the LLT information.

15. A processing device configured to control a first station STA 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 perform operations based on execution by the at least one processor, the operations including: Receive Physical Layer Protocol Data Unit (PPDU) including the first trigger frame from the access point (AP); and Based on the first trigger frame, send at least one of a first low-latency service (LLT) or LLT information related to the first LLT to the AP. The first trigger frame includes: i) first information indicating whether the first trigger frame is related to the transmission of the first LLT or the LLT information, and ii) second information related to the random access resource unit (RA-RU) for the transmission of the first LLT or the LLT information.

16. At least one non-transitory computer-readable medium, said at least one non-transitory computer-readable medium storing at least one instruction, in, The at least one instruction, executable by at least one processor, controls the devices in the wireless LAN system to: Receive Physical Layer Protocol Data Unit (PPDU) including the first trigger frame from the access point (AP); as well as Based on the first trigger frame, send at least one of a first low-latency service (LLT) or LLT information related to the first LLT to the AP. The first trigger frame includes: i) first information indicating whether the first trigger frame is related to the transmission of the first LLT or the LLT information, and ii) second information related to the random access resource unit (RA-RU) for the transmission of the first LLT or the LLT information.

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