Method and apparatus for transmitting and receiving trigger frames in a wireless LAN system

Abstract

A method and apparatus operating in a wireless LAN system are disclosed. A method performed by a first STA in a wireless LAN system according to an embodiment of the present disclosure includes receiving an aggregated (A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame from a second STA, and performing uplink transmission based on the first trigger frame and the second trigger frame. The first trigger frame may include first information indicating at least one resource unit (RU) within a primary channel bandwidth, and the second trigger frame may include second information indicating at least one resource unit (RU) within a secondary channel bandwidth.

Description

Technical Field

[0001] The present disclosure relates to communication operations in a Wireless Local Area Network (WLAN) system, and more particularly, to a method and apparatus for transmitting and receiving one or more trigger frames in a WLAN system.

Background Art

[0002] New technologies for improving the transmission rate, increasing the bandwidth, improving the reliability, reducing errors, and reducing latency have been introduced for Wireless Local Area Network (WLAN). Among WLAN technologies, the standards of the Institute of Electrical and Electronics Engineers (IEEE) 802.11 series can be referred to as Wi-Fi. For example, technologies recently introduced into WLAN include enhancements for Very High-Throughput (VHT) of the 802.11ac standard, enhancements for High Efficiency (HE) of the IEEE 802.11ax standard, and the like.

[0003] To provide a more improved wireless communication environment, improvement technologies for Extremely High Throughput (EHT) are being discussed. For example, technologies for increased bandwidth, efficient utilization of multiple bands, Multiple Input Multiple Output (MIMO) to support increased spatial streams, and technologies for multi-access point (AP) coordination are being studied. In particular, various technologies for supporting traffic with low latency or real-time characteristics are being studied. In addition, new technologies for supporting ultra high reliability (UHR), including improvements or extensions of EHT technology, are being discussed.

Summary of the Invention

Problems to be Solved by the Invention

[0004] The technical problem of the present disclosure is to provide a method and an apparatus for transmitting and receiving one or more trigger frames in a wireless LAN system.

[0005] The technical problem of the present disclosure is to provide a method and an apparatus for transmitting and receiving an A-MPDU composed of two trigger frames.

[0006] Among the two trigger frames included in the A-MPDU, the technical problem of the present disclosure is to provide a method in which at least one RU (resource unit) of the primary channel is indicated by the trigger frame located in the front, and at least one RU of the secondary channel is indicated by the trigger frame located in the back.

[0007] The technical problem to be achieved in the present disclosure is not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those having ordinary knowledge in the technical field to which the present disclosure belongs from the following description.

Means for Solving the Problems

[0008] A method performed by a first station (STA) in a wireless LAN system according to an aspect of the present disclosure includes receiving, from a second STA, an aggregated (A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame, and performing uplink transmission based on the first trigger frame and the second trigger frame. The first trigger frame may include first information indicating at least one resource unit (RU) within a primary channel bandwidth, and the second trigger frame may include second information indicating at least one resource unit (RU) within a secondary channel bandwidth.

[0009] In a wireless LAN system according to one aspect of the present disclosure, a method performed by a second station (STA) includes transmitting an aggregated (A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame to a first STA, and performing uplink reception based on the first trigger frame and the second trigger frame. The first trigger frame includes first information indicating at least one resource unit (RU) within a primary channel bandwidth, and the second trigger frame may include second information indicating at least one resource unit (RU) within a secondary channel bandwidth.

Advantages of the Invention

[0010] According to various embodiments of the present disclosure, a method and apparatus for transmitting and receiving one or more trigger frames in a wireless LAN system can be provided.

[0011] According to various embodiments of the present disclosure, a method and apparatus for transmitting and receiving an A-MPDU composed of two trigger frames can be provided.

[0012] According to various embodiments of the present disclosure, a method can be provided in which, among two trigger frames included in an A-MPDU, an RU (resource unit) of a primary channel is indicated by a trigger frame located in front, and an RU of a secondary channel is indicated by a trigger frame located behind.

[0013] The effects obtained from the present disclosure are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those of ordinary skill in the technical field to which the present disclosure pertains from the following description.

Brief Description of the Drawings

[0014] The accompanying drawings, which are included as a part of the detailed description to assist in understanding the present disclosure, provide examples of embodiments of the present disclosure and, together with the detailed description, explain the technical features of the present disclosure.

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DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, preferred embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description disclosed below together with the accompanying drawings is for explaining exemplary embodiments of the present disclosure and is not for showing the only embodiments in which the present disclosure can be implemented. The following detailed description includes specific details in order to provide a complete understanding of the present disclosure. However, it is understood by those skilled in the art that the present disclosure can be implemented without such specific details.

[0016] In some cases, to avoid obscuring the concepts of the present disclosure, well-known structures and devices may be omitted, or may be shown in the form of a block diagram centered on the core functions of each structure and device.

[0017] In the present disclosure, when a certain component is "connected", "coupled" or "connected" to another component, this may include not only a direct connection relationship, but also an indirect connection relationship in which there are further other components between them. Also, in the present disclosure, the terms "comprising" or "having" are used to identify the presence of the recited features, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components and / or groups thereof.

[0018] In the present disclosure, terms such as "first", "second", etc. are used only for the purpose of distinguishing one component from another and are not used to limit the components. Unless otherwise specifically mentioned, they do not limit the order or importance, etc. between the components. Therefore, within the scope of the present disclosure, the first component in one embodiment can also be referred to as the second component in another embodiment, and similarly, the second component in one embodiment can also be referred to as the first component in another embodiment.

[0019] The terms used in this disclosure are for the purpose of describing specific embodiments and are not intended to limit the scope of the claims. As used in the description of the embodiments and the appended claims, the singular forms are also intended to include the plural forms unless the context clearly dictates otherwise. The term "and / or" as used in this disclosure may refer to one of the related listed items or include any and all possible combinations of two or more of them. Also, in this disclosure, the " / " between words has the same meaning as "and / or" unless otherwise specified.

[0020] The examples of this disclosure may be applied to various wireless communication systems. For example, the examples of this disclosure may be applied to a wireless LAN system. For example, the examples of this disclosure may be applied to an IEEE 802.11a / g / n / ac / ax standard-based wireless LAN. Note that the examples of this disclosure may be applied to a newly proposed IEEE 802.11bn (or, UHR) standard-based wireless LAN. Furthermore, the examples of this disclosure may also be applied to a next-generation standard-based wireless LAN after IEEE 802.11bn. Also, the examples of this disclosure may be applied to a cellular wireless communication system. For example, it may be applied to a cellular wireless communication system based on the technologies of the LTE (Long Term Evolution) series and the 5G NR (New Radio) series of the 3GPP (registered trademark: 3rd Generation Partnership Project) standard.

[0021] Hereinafter, the technical features to which the examples of this disclosure can be applied will be described.

[0022] FIG. 1 is a block configuration diagram illustrating a wireless communication device according to an embodiment of this disclosure.

[0023] The first device 100 and the second device 200 illustrated in FIG. 1 may be referred to by various terms such as a terminal, a wireless device, a WTRU (Wireless Transmit Receive Unit), a UE (User Equipment), an MS (Mobile Station), a UT (user terminal), an MSS (Mobile Subscriber Station), an MSS (Mobile Subscriber Unit), an SS (Subscriber Station), an AMS (Advanced Mobile Station), a WT (Wireless terminal), or simply a user. Also, the first device 100 and the second device 200 may be referred to by various terms such as an access point (AP), a BS (Base Station), a fixed station, a Node B, a BTS (base transceiver system), a network, an AI (Artificial Intelligence) system, an RSU (road side unit), a repeater, a router, a relay, a gateway, etc.

[0024] The devices 100 and 200 illustrated in FIG. 1 may also be referred to as a station (STA). For example, the devices 100 and 200 illustrated in FIG. 1 may be referred to by various terms such as a transmitting device, a receiving device, a transmitting STA, a receiving STA, etc. For example, the STAs 110 and 200 may play the role of an AP (access point) or a non-AP. That is, in the present disclosure, the STAs 110 and 200 may have the functions of an AP and / or a non-AP. When the STAs 110 and 200 have the AP function, they may simply be referred to as an AP, and when the STAs 110 and 200 have the non-AP function, they may simply be referred to as an STA. Also, in the present disclosure, an AP may be denoted as an AP STA.

[0025] Referring to FIG. 1, the first device 100 and the second device 200 can transmit and receive wireless signals using various wireless LAN technologies (e.g., IEEE 802.11 series). The first device 100 and the second device 200 may include interfaces for a medium access control (MAC) layer and a physical layer (PHY) that comply with the provisions of the IEEE 802.11 standard.

[0026] In addition, the first device 100 and the second device 200 can further support various communication standards other than wireless LAN technologies (e.g., 3GPP LTE series, 5G NR series standards, etc.). Also, the devices of the present disclosure may be implemented by various devices such as mobile phones, vehicles, personal computers, AR (Augmented Reality) equipment, VR (Virtual Reality) equipment, etc. Further, the STAs in this specification can support various communication services such as voice calls, video calls, data communication, autonomous driving, MTC (Machine-Type Communication), M2M (Machine-to-Machine), D2D (Device-to-Device), IoT (Internet-of-Things), etc.

[0027] The first device 100 includes one or more processors 102 and one or more memories 104, and may further include one or more transceivers 106 and / or one or more antennas 108. The processor 102 controls the memory 104 and / or the transceiver 106, and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts in the present disclosure. For example, after processing the information in the memory 104 to generate a first information / signal, the processor 102 can transmit a wireless signal including the first information / signal via the transceiver 106. Also, after receiving a wireless signal including a second information / signal via the transceiver 106, the processor 102 can store the information obtained from the signal processing of the second information / signal in the memory 104. The memory 104 may be connected to the processor 102 and can store various information related to the operation of the processor 102. For example, the memory 104 can store software code including instructions for executing part or all of the processes controlled by the processor 102 or for executing the descriptions, functions, procedures, proposals, methods, and / or operation sequence diagrams in the present disclosure. Here, the processor 102 and the memory 104 may be part of a communication modem / circuit / chip designed to implement wireless LAN technology (e.g., the IEEE 802.11 series). The transceiver 106 may be connected to the processor 102 and can transmit and / or receive wireless signals via one or more antennas 108. The transceiver 106 may include a transmitter and / or a receiver. The transceiver 106 may be used in the same sense as an RF (Radio Frequency) unit. In the present disclosure, the device can also mean a communication modem / circuit / chip.

[0028] The second device 200 includes one or more processors 202 and one or more memories 204, and may further include one or more transceivers 206 and / or one or more antennas 208. The processor 202 may control the memory 204 and / or the transceiver 206, and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operation sequence diagrams disclosed in the present disclosure. For example, after processing the information in the memory 204 to generate third information / signal, the processor 202 may transmit a wireless signal including the third information / signal via the transceiver 206. Also, after receiving a wireless signal including fourth information / signal via the transceiver 206, the processor 202 may store the information obtained from the signal processing of the fourth information / signal in the memory 204. The memory 204 may be connected to the processor 202 and can store various information related to the operation of the processor 202. For example, the memory 204 may execute part or all of the processes controlled by the processor 202, or store software code including instruction words for implementing the descriptions, functions, procedures, proposals, methods, and / or operation sequence diagrams disclosed in the present disclosure. Here, the processor 202 and the memory 204 may be part of a communication modem / circuit / chip designed to implement wireless LAN technology (e.g., IEEE 802.11 series). The transceiver 206 may be connected to the processor 202 and can transmit and / or receive wireless signals via one or more antennas 208. The transceiver 206 may include a transmitter and / or a receiver. The transceiver 206 may be used in the same sense as an RF unit. In the present disclosure, the device may also mean a communication modem / circuit / chip.

[0029] Hereinafter, the hardware elements of devices 100 and 200 will be described in more detail. Although 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 can implement one or more layers (e.g., functional layers such as PHY and MAC). One or more processors 102 and 202 can generate one or more PDUs (Protocol Data Units) and / or one or more SDUs (Service Data Units) according to the descriptions, functions, procedures, proposals, methods, and / or operation sequence diagrams in the present disclosure. One or more processors 102 and 202 can generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation sequence diagrams in the present disclosure. One or more processors 102 and 202 can generate a signal (e.g., a baseband signal) including a PDU, an SDU, a message, control information, data, or information according to the functions, procedures, proposals, and / or methods in the present disclosure and provide it to one or more transceivers 106 and 206. One or more processors 102 and 202 can receive a signal (e.g., a baseband signal) from one or more transceivers 106 and 206 and obtain a PDU, an SDU, a message, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation sequence diagrams in the present disclosure.

[0030] One or more processors 102, 202 can be referred to as a controller, microcontroller, microprocessor, or microcomputer. The one or more processors 102, 202 may be embodied by hardware, firmware, software, or a combination thereof. As an example, one or more ASICs (Application Specific Integrated Circuits), one or more DSPs (Digital Signal Processors), one or more DSPDs (Digital Signal Processing Devices), one or more PLDs (Programmable Logic Devices), or one or more FPGAs (Field Programmable Gate Arrays) may be included in the one or more processors 102, 202. The descriptions, functions, procedures, proposals, methods, and / or operation sequence diagrams disclosed in the present disclosure may be embodied using firmware or software, and the firmware or software may be embodied to include modules, procedures, functions, and the like. The firmware or software configured to execute the descriptions, functions, procedures, proposals, methods, and / or operation sequence diagrams disclosed in the present disclosure may be included in the one or more processors 102, 202, stored in the one or more memories 104, 204, and driven by the one or more processors 102, 202. The descriptions, functions, procedures, proposals, methods, and / or operation sequence diagrams disclosed in the present disclosure may be embodied by firmware or software in the form of code, instruction words, and / or a set of instruction words.

[0031] One or more memories 104, 204 may be coupled to one or more processors 102, 202 and can store various forms of data, signals, messages, information, programs, code, instructions, and / or commands. The one or more memories 104, 204 may be constituted by ROM, RAM, EPROM, flash memory, hard drive, register, cache memory, computer-readable storage medium, and / or combinations thereof. The one or more memories 104, 204 may be located inside and / or outside the one or more processors 102, 202. Also, the one or more memories 104, 204 may be coupled to the one or more processors 102, 202 by various techniques such as wired or wireless connections.

[0032] One or more transceivers 106, 206 can transmit user data, control information, wireless signals / channels, etc. mentioned in the methods and / or operation sequence diagrams of the present 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, procedures, proposals, methods, and / or operation sequence diagrams disclosed in the present disclosure from one or more other devices. For example, one or more transceivers 106, 206 may be connected to one or more processors 102, 202 and 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. Also, 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. Also, 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, procedures, proposals, methods, and / or operation sequence diagrams disclosed in the present disclosure via one or more antennas 108, 208. In the present 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 to baseband signals in order to process the received user data, control information, wireless signals / channels, etc. 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 to RF band signals. For this purpose, one or more transceivers 106, 206 may include (analog) oscillators and / or filters.

[0033] For example, either one of STA100 and 200 can perform the intended operation of the AP, and the other one of STA100 and 200 can perform the intended operation of a non-AP STA. For example, the transceivers 106 and 206 in FIG. 1 can perform the transmission and reception operations of signals (for example, packets or PPDUs (Physical layer Protocol Data Units) compliant with IEEE 802.11a / b / g / n / ac / ax / be / bn, etc.). Also, in the present disclosure, operations in which various STAs generate transmission and reception signals or perform data processing and calculations in advance for the transmission and reception signals may be performed by the processors 102 and 202 in FIG. 1. For example, an example of an operation of generating a transmission and reception signal or performing data processing and calculations in advance for the transmission and reception signal is: 1) an operation of determining / acquiring / configuring / calculating / decoding / encoding bit information of fields (such as SIG (signal), STF (short training field), LTF (long training field), Data, etc.) included in the PPDU; 2) an operation of determining / configuring / acquiring time resources and frequency resources (such as subcarrier resources) used for fields (such as SIG, STF, LTF, Data, etc.) included in the PPDU; 3) an operation of determining / configuring / acquiring a specific sequence (such as a pilot sequence, STF / LTF sequence, extra sequence applied to SIG) used for fields (such as SIG, STF, LTF, Data, etc.) included in the PPDU; 4) a power control operation and / or a power saving operation applied to the STA; 5) operations related to determining / acquiring / configuring / calculating / decoding / encoding an ACK signal may be included. Also, in the following example, various information (for example, information related to fields / sub-fields / control fields / parameters / power, etc.) used by various STAs for determining / acquiring / configuring / calculating / decoding / encoding transmission and reception signals may be stored in the memories 104 and 204 in FIG. 1.

[0034] Hereinafter, the downlink (DL) means a link for communication from an AP STA to a non-AP STA, and downlink PPDU / packets / signals, etc. may be transmitted and received through the downlink. In downlink communication, the transmitter may be part of the AP STA, and the receiver may be part of the non-AP STA. The uplink (UL) means a link for communication from a non-AP STA to an AP STA, and uplink PPDU / packets / signals, etc. may be transmitted and received through the uplink. In uplink communication, the transmitter may be part of the non-AP STA, and the receiver may be part of the AP STA.

[0035] FIG. 2 is a diagram showing an exemplary structure of a wireless LAN system to which the present disclosure is applicable.

[0036] The structure of the wireless LAN system may be composed of a plurality of components. A wireless LAN that supports STA mobility transparent to the upper layer may be provided by the interaction of the plurality of components. A BSS (Basic Service Set) corresponds to the basic building block of the wireless LAN. In FIG. 2, two BSSs (BSS1 and BSS2) are present, and it is exemplified that two STAs are included as members of each BSS (STA1 and STA2 are included in BSS1, and STA3 and STA4 are included in BSS2). In FIG. 2, the ellipse representing the BSS may be understood to represent the coverage area in which the STAs included in the BSS maintain communication. This area can be referred to as a BSA (Basic Service Area). When a STA moves outside the BSA, it can no longer communicate directly with other STAs within the BSA.

[0037] If the DS shown in FIG. 2 is not considered, the most basic type of BSS in a wireless LAN is an Independent BSS (IBSS). For example, an IBSS can have the smallest form consisting of only two STAs. For example, assuming that other components are omitted, BSS1 consisting of only STA1 and STA2, or BSS2 consisting of only STA3 and STA4 can each correspond to a typical example of an IBSS. Such a configuration is possible when STAs can communicate directly without an AP. Also, such a form of wireless LAN is not pre-planned and configured, but can be configured when a LAN is needed, and this can also be referred to as an ad-hoc network. Since an IBSS does not include an AP, there is no centralized management entity that performs management functions centrally. That is, in an IBSS, STAs are managed in a distributed manner. In an IBSS, all STAs may be composed of mobile STAs, connection to a distributed system (DS) is not allowed, and it forms a self-contained network.

[0038] The membership of STAs in a BSS may be dynamically changed due to STAs joining or leaving, or STAs entering or exiting the BSS area. To become a member of a BSS, an STA can join the BSS using a synchronization process. To access all services of the BSS-based structure, an STA needs to be associated with the BSS. Such an association may be set dynamically and may include the use of a Distribution System Service (DSS).

[0039] In a wireless LAN, the direct STA-to-STA distance may be limited by PHY performance. In some cases, such distance limitations may be sufficient, but in some cases, communication between STAs at a greater distance may be required. A distributed system (DS) may be configured to support extended coverage.

[0040] DS means a structure in which BSSs are interconnected. Specifically, as shown in FIG. 2, a BSS may exist as a component of an extended form of a network composed of a plurality of BSSs. DS is a logical concept and may be specified by the characteristics of the distributed system medium (DSM). In this regard, the wireless medium (WM) and the DSM may be logically separated. Each logical medium is used for different purposes and is used by different components. These media are not limited to being the same or different. The flexibility of the wireless LAN structure (DS structure or other network structures) can be explained by the fact that multiple media are logically different from each other. That is, the wireless LAN structure may be implemented in various ways, and the wireless LAN structure may be specified independently according to the physical characteristics of each implementation example.

[0041] DS can support mobile devices by providing seamless integration of multiple BSSs and providing the logical services necessary for handling addresses to destinations. In addition, DS may further include a component called a portal that acts as a bridge for connecting a wireless LAN to other networks (e.g., IEEE 802.X).

[0042] AP means an entity that enables access to the DS through the WM for an associated non-AP STA and also has the functionality of the STA. Data movement between the BSS and the DS can be performed via the AP. For example, the STAs 2 and 3 shown in FIG. 2 provide the function of enabling the associated non-AP STAs (STAs 1 and 4) to access the DS while having the functionality of the STA. Also, since all APs basically correspond to STAs, all APs are addressable entities. The address used by the AP for communication on the WM and the address used by the AP for communication on the DSM do not necessarily have to be the same. A BSS composed of an AP and one or more STAs can be referred to as an infrastructure BSS.

[0043] Data transmitted from one of the STAs associated with the AP to the STA address of the AP is always received at the uncontrolled port and may be processed by the IEEE 802.1X port access entity. Also, when the controlled port is authenticated, the transmitted data (or frame) can be transmitted to the DS.

[0044] An Extended Service Set (ESS) for providing a wider coverage may be set in the structure of the DS described above.

[0045] An ESS means a network composed of a DS and BSSs with arbitrary size and complexity. An ESS can correspond to a set of BSSs connected to one DS. However, an ESS does not include a DS. The ESS network is characterized in that it appears as an IBSS at the LLC (Logical Link Control) layer. STAs included in an ESS can communicate with each other, and a mobile STA can transparently move from one BSS to another (within the same ESS) to the LLC. APs included in one ESS may have the same SSID (service set identification). The SSID is distinguished from the BSSID which is an identifier of a BSS.

[0046] In a wireless LAN system, without making any assumptions about the relative physical positions of BSSs, any of the following forms is possible. BSSs may partially overlap, which is a commonly used form to provide continuous coverage. Also, BSSs do not have to be physically connected, and logically there is no limit to the distance between BSSs. Also, BSSs may be physically located at the same position, which may be used to provide redundancy. Also, one (or one or more) IBSS or ESS networks may physically exist in the same space as one (or one or more) ESS networks. This may correspond to the ESS network form when an ad hoc network operates at the location where an ESS network exists, when wireless networks physically overlapping are configured by different organizations, or when two or more different access and security policies are required at the same location.

[0047] Figure 3 is a diagram for explaining a link setup process to which the present disclosure is applicable.

[0048] In order for a STA to set up a link with a network and transmit and receive data, it must first discover the network, perform authentication, establish an association, and carry out authentication procedures for security purposes. The link setup process can be referred to as the session start process and the session setup process. Also, the processes of discovery, authentication, association, and security setup in the link setup process can be collectively referred to as the association process.

[0049] In step S310, the STA can perform a network discovery operation. The network discovery operation may include the scanning operation of the STA. That is, in order for the STA to access the network, it must search for available networks to participate in. The STA must identify compatible networks before participating in a wireless network, and the process of identifying networks existing in a specific area is called scanning.

[0050] Scanning methods include active scanning and passive scanning. In FIG. 3, by way of example, a network discovery operation including an active scanning process is shown. In active scanning, the STA performing the scanning sends a probe request frame and waits for a response thereto in order to search for what APs exist in the vicinity while moving channels. 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. Since the AP sends a beacon frame in the BSS, the AP becomes the responder. In an IBSS, since the STAs within the IBSS send beacon frames alternately, the responder is not constant. For example, a STA that sends a probe request frame on channel 1 and receives a probe response frame on channel 1 saves the BSS-related information included in the received probe response frame, moves to the next channel (e.g., channel 2), and can perform scanning in the same way (i.e., send and receive probe requests / responses on channel 2).

[0051] Although not shown in FIG. 3, the scanning operation may be performed in a passive scanning mode. In passive scanning, the STA performing the scanning waits for beacon frames while moving channels. A beacon frame is one of the management frames defined in IEEE 802.11, which notifies the presence of a wireless network and is periodically transmitted so that a STA performing scanning can search for a wireless network and participate in the wireless network. In a BSS, the AP is responsible for periodically transmitting beacon frames, and in an IBSS, the STAs within the IBSS transmit beacon frames alternately. When the STA performing scanning receives a beacon frame, it saves the information about the BSS contained in the beacon frame and records the beacon frame information on each channel while moving to other channels. The STA that has received the beacon frame can save the BSS-related information contained in the received beacon frame and move to the next channel to perform scanning on the next channel in the same way. Comparing active scanning and passive scanning, active scanning has the advantage that the delay and power consumption are smaller than those of passive scanning.

[0052] After the STA discovers the network, the authentication process may be performed in step S320. Such an authentication process can be called the first authentication process in order to clearly distinguish it from the security setup operation in step S340 described later.

[0053] The authentication process includes a process in which the STA transmits an authentication request frame to the AP and, in response, the AP transmits an authentication response frame to the STA. The authentication frame used for authentication request / response corresponds to a management frame.

[0054] The authentication frame may include information regarding the authentication algorithm number, authentication transaction sequence number, status code, challenge text, RSN (Robust Security Network), Finite Cyclic Group, etc. This corresponds to an example of some of the information that may be included in the authentication request / response frame, and may be replaced by other information or further additional information may be included.

[0055] The STA can send an authentication request frame to the AP. The AP can determine whether to allow the authentication of the STA based on the information included in the received authentication request frame. The AP can provide the result of the authentication process to the STA using an authentication response frame.

[0056] After the STA is successfully authenticated, the association process may be performed at step S330. The association process includes the process in which the STA sends an association request frame to the AP and, in response, the AP sends an association response frame to the STA.

[0057] For example, the association request frame may include information regarding various capabilities, beacon listen interval, SSID (service set identifier), supported rates, supported channels, RSN, mobility domain, supported operating classes, TIM (Traffic Indication Map) broadcast request, information regarding interworking service capabilities, and the like. For example, the association response frame may include information regarding various capabilities, status code, AID (Association ID), supported rates, EDCA (Enhanced Distributed Channel Access) parameter set, RCPI (Received Channel Power Indicator), RSNI (Received Signal to Noise Indicator), mobility domain, timeout interval (e.g., association comeback time), overlapping BSS scan parameters, TIM broadcast response, QoS (Quality of Service) map, and the like. This corresponds to an exemplification of some of the information that may be included in the association request / response frame, and may be replaced by other information or may further include additional information.

[0058] After the STA successfully associates with the network, a security setup process may be performed at step S340. The security setup process at step S340 may also be referred to as an authentication process using RSNA (Robust Security Network Association) request / response. The authentication process at step S320 may be referred to as the first authentication process, and the security setup process at step S340 may simply be referred to as the authentication process.

[0059] The security setup process in stage S340 may include a process of setting up a private key using, for example, a 4-way handshake using an EAPOL (Extensible Authentication Protocol over LAN) frame. Further, the security setup process may be performed by a security method not defined in the IEEE 802.11 standard.

[0060] FIG. 4 is a diagram for explaining a backoff process to which the present disclosure is applicable.

[0061] In a wireless LAN system, the basic access mechanism of MAC (Medium Access Control) is the CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) mechanism. The CSMA / CA mechanism is also called the Distributed Coordination Function (DCF) of the IEEE 802.11 MAC, but basically adopts a "listen before talk" access mechanism. According to such a type of access mechanism, the AP and / or STA can perform a Clear Channel Assessment (CCA) to sense the wireless channel or medium (for example, DIFS (DCF Inter-Frame Space)) for a predetermined time interval before starting transmission. As a result of sensing, if it is determined that the medium is in an idle status, frame transmission is started through the medium. On the other hand, if the medium is sensed as being in an occupied or busy state, the AP and / or STA does not start its own transmission, sets a delay period for medium access (for example, a random backoff period), waits, and then can attempt frame transmission. By applying the random backoff period, it is expected that multiple STAs will attempt frame transmission after waiting for different times from each other, so collisions can be minimized.

[0062] In addition, the IEEE 802.11 MAC protocol provides HCF (Hybrid Coordination Function). HCF is based on the above-mentioned DCF and PCF (Point Coordination Function). PCF refers to a polling-based synchronous access method, which periodically polls so that all receiving APs and / or STAs can receive data frames. Also, HCF has EDCA (Enhanced Distributed Channel Access) and HCCA (HCF Controlled Channel Access). EDCA is an access method in which the provider makes the access method for providing data frames to multiple users be contention-based, and HCCA is to use a non-contention-based channel access method using a polling mechanism. Also, HCF includes a medium access mechanism for improving the QoS (Quality of Service) of a wireless LAN, and QoS data can be transmitted in either a Contention Period (CP) or a Contention Free Period (CFP).

[0063] Referring to FIG. 4, the operation based on the random backoff period will be described. When the medium that was in the occupied / busy state changes to the idle state, multiple STAs can attempt to transmit data (or frames). As a solution to minimize collisions, each STA can select a random backoff count and attempt transmission after waiting for the corresponding slot time. The random backoff count has a pseudo-random integer value and can be determined to be any one of the values in the range of 0 to CW. Here, CW is the contention window parameter value. The CW parameter is given an initial value of CWmin, but can take a value twice as large in the case of a transmission failure (for example, when an ACK for the transmitted frame cannot be received). When the CW parameter value reaches CWmax, data transmission can be attempted while maintaining the CWmax value until data transmission is successful, and when data transmission is successful, it is reset to the CWmin value. The CW, CWmin, and CWmax values are preferably set to 2 n -1 (n = 0, 1, 2,...).

[0064] When the random backoff process starts, the STA continues to monitor the medium while counting down the backoff slots by the determined backoff count value. When the medium is monitored as being in the occupied state, the countdown stops and it waits, and when the medium becomes idle, the remaining countdown resumes.

[0065] In the example of FIG. 4, when a packet to be transmitted arrives at the MAC of STA3, STA3 can confirm that the medium has been idle for only the DIFS period and immediately transmit a frame. The remaining STAs monitor that the medium is in the occupied / busy state and wait. During this time, data to be transmitted may occur at each of STA1, STA2, and STA5. Each STA can count down the backoff slots according to the random backoff count value it has selected after waiting for only the DIFS period when the medium is monitored as being in the idle state. Assume that STA2 selects the minimum backoff count value and STA1 selects the maximum backoff count value. That is, an example is illustrated where the remaining backoff time of STA5 is shorter than the remaining backoff time of STA1 when STA2 finishes the backoff count and starts frame transmission. STA1 and STA5 stop counting down and wait for a while while STA2 occupies the medium. When STA2's occupation ends and the medium becomes idle again, STA1 and STA5 wait for only the DIFS period and then resume the stopped backoff count. That is, frame transmission can be started after counting down the remaining backoff slots for only the remaining backoff time. Since the remaining backoff time of STA5 is shorter than that of STA1, STA5 starts frame transmission. Data to be transmitted may also occur at STA4 while STA2 occupies the medium. From the perspective of STA4, when the medium becomes idle, after waiting for only the DIFS period, it can count down according to the random backoff count value it has selected and start frame transmission. The example of FIG. 4 shows a case where the remaining backoff time of STA5 accidentally coincides with the random backoff count value of STA4. In this case, a collision may occur between STA4 and STA5. If a collision occurs, neither STA4 nor STA5 can receive an ACK, and the data transmission will fail. In this case, STA4 and STA5 can select a random backoff count value after doubling the CW value and perform the countdown.STA1 waits while the medium is busy due to the transmissions of STA4 and STA5. However, when the medium becomes idle, after waiting for only DIFS and when the remaining backoff time has elapsed, STA1 can start transmitting a frame.

[0066] As illustrated in FIG. 4, a data frame is a frame used for transmitting data to be forwarded to a higher layer, and may be transmitted after a backoff that occurs after DIFS has elapsed since the medium became idle. Further, a management frame is a frame used for exchanging management information that is not forwarded to a higher layer, and is transmitted after a backoff that occurs after an IFS such as DIFS or PIFS (Point coordination function IFS) has elapsed. As subtypes of management frames, there are Beacon, Association request / response, Re - association request / response, Probe request / response, Authentication request / response, etc. A control frame is a frame used for controlling access to the medium. As subtypes of control frames, there are Request-To-Send (RTS), Clear-To-Send (CTS), Acknowledgment (ACK), Power Save-Poll (PS-Poll), BlockAck, BlockACKReq, null data packet announcement (NDP), Trigger, etc. A control frame is transmitted after a backoff that occurs after DIFS has elapsed when it is not a response frame to a previous frame, and is transmitted without a backoff after SIFS has elapsed when it is a response frame to a previous frame. The type and subtype of a frame may be identified by the type field and subtype field in the Frame Control (FC) field.

[0067] A QoS (Quality of Service) STA can transmit a frame after performing a backoff that occurs after the expiration of AIFS (Arbitration IFS) for the access category (AC) to which the frame belongs, i.e., AIFS[i] (where i is a value determined by the AC). Here, frames for which AIFS[i] can be used can be data frames, management frames, or control frames that are not response frames.

[0068] FIG. 5 is a diagram for explaining a CSMA / CA-based frame transmission operation to which the present disclosure is applicable.

[0069] As described above, the CSMA / CA mechanism includes virtual carrier sensing in addition to physical carrier sensing in which a STA directly senses the medium. Virtual carrier sensing is for complementing problems that may occur in medium access, such as the hidden node problem. For virtual carrier sensing, the MAC of a STA can utilize a NAV (Network Allocation Vector). The NAV is a value that indicates to other STAs the time remaining until the medium becomes available for a STA that is currently using the medium or has the authority to use it. Therefore, the value set as the NAV corresponds to the period during which the use of the medium is planned by the STA transmitting the frame, and the STA receiving the NAV value is prohibited from accessing the medium during that period. For example, the NAV may be set based on the value of the "duration" field in the MAC header of the frame.

[0070] In the example of FIG. 5, assume that STA1 is about to transmit data to STA2, and STA3 is in a position where it can overhear part or all of the frames transmitted and received between STA1 and STA2.

[0071] In order to reduce the possibility of transmission collisions among multiple STAs in the CSMA / CA-based frame transmission operation, a mechanism using RTS / CTS frames may be applied. In the example of FIG. 5, while the transmission of STA1 is in progress, as a result of the carrier sensing of STA3, it may be determined that the medium is idle. That is, STA1 may correspond to a hidden node to STA3. Or, in the example of FIG. 5, while the transmission of STA2 is in progress, as a result of the carrier sensing of STA3, it may be determined that the medium is idle. That is, STA2 may correspond to a hidden node to STA3. Before performing data transmission and reception between STA1 and STA2, by exchanging RTS / CTS frames, STAs outside the transmission range of either STA1 or STA2, or STAs outside the carrier sensing range for the transmission from STA1 or STA3, can be prevented from attempting to occupy the channel during the data transmission and reception between STA1 and STA2.

[0072] Specifically, STA1 can use carrier sensing to determine whether the channel is in use. In terms of physical carrier sensing, STA1 can determine the channel occupancy idle state based on the energy magnitude or signal correlation detected from the channel. Also, in terms of virtual carrier sensing, STA1 can use the NAV (network allocation vector) timer to determine the occupancy state of the channel.

[0073] When the channel is in an idle state at DIFS, STA1 can transmit an RTS frame to STA2 after performing a backoff. When STA2 receives the RTS frame, it can transmit a CTS frame, which is a response to the RTS frame, to STA1 after SIFS.

[0074] Although STA3 cannot overhear the CTS frame from STA2, if it can overhear the RTS frame 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). Or, although STA3 cannot overhear the RTS frame from STA1, if it can overhear the CTS frame from STA2, STA3 can 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). That is, when STA3 can overhear one or more of the RTS or CTS frames from at least one of STA1 or STA2, it can set the NAV based on this. If STA3 receives a new frame before the NAV timer expires, it can update the NAV timer using the duration information included in the new frame. STA3 does not attempt channel access until the NAV timer expires.

[0075] When STA1 receives a CTS frame from STA2, it can transmit a data frame to STA2 after SIFS from the time when the reception of the CTS frame is completed. When STA2 successfully receives the data frame, it can transmit an ACK frame, which is a response to the data frame, to STA1 after SIFS. When the NAV timer of STA3 expires, it can use carrier sensing to determine whether the channel is in use. If STA3 determines that the channel is not used by other terminals during the period from the expiration of the NAV timer to DIFS, it can attempt channel access after the contention window (CW) by random backoff has passed.

[0076] FIG. 6 is a diagram for explaining an example of a frame structure used in a wireless LAN system to which the present disclosure is applicable.

[0077] By an instruction or primitive (meaning a set of an instruction or parameters) from the MAC layer, the PHY layer can prepare an MPDU (MAC PDU) to be transmitted. For example, when receiving an instruction requesting the start of transmission from the MAC layer, the PHY layer switches to the transmission mode and can configure and transmit the information (e.g., data) provided from the MAC layer in the form of a frame. Also, in the PHY layer, when detecting a valid preamble of the received frame, the PHY layer monitors the preamble header and sends an instruction to the MAC layer notifying the start of reception in the PHY layer.

[0078] Thus, information transmission / reception in the wireless LAN system is performed in the form of a frame, and for this purpose, a Physical layer Protocol Data Unit (PPDU) frame format is defined.

[0079] A basic PPDU may include a STF (Short Training Field), an LTF (Long Training Field), a SIG (SIGNAL) field, and a Data field. The most basic (e.g., non-HT (High Throughput) shown in FIG. 7) PPDU format may be composed of only an L-STF (Legacy-STF), an L-LTF (Legacy-LTF), an L-SIG (Legacy-SIG) field, and a Data field. Also, depending on the type of PPDU format (e.g., HT-mixed format PPDU, HT-greenfield format PPDU, VHT (Very High Throughput) PPDU, etc.), additional (or other types of) RL-SIG, U-SIG, non-legacy SIG fields, non-legacy STF, non-legacy LTF (i.e., xx-SIG, xx-STF, xx-LTF (e.g., xx is HT, VHT, HE, EHT, etc.)) may be included between the L-SIG field and the Data field. For more specific matters, refer to FIG. 7 and it will be described later.

[0080] The STF is a signal for signal detection, AGC (Automatic Gain Control), diversity selection, precise time synchronization, etc., and the LTF is a signal for channel estimation, frequency error estimation, etc. It can be said that the STF and the LTF are signals for synchronization and channel estimation of the OFDM physical layer.

[0081] The SIG field may contain various information related to PPDU transmission and reception. For example, the L-SIG field may be composed of 24 bits, and the L-SIG field may include a 4-bit Rate field, a 1-bit Reserved bit, a 12-bit Length field, a 1-bit Parity field, and a 6-bit Tail field. The RATE field may contain information regarding the modulation and coding rate of the data. For example, the 12-bit Length field may contain information regarding the length or time duration of the PPDU. For example, the value of the 12-bit Length field may be determined based on the type of PPDU. For example, for non-HT, HT, VHT, or EHT PPDUs, the value of the Length field may be determined to be a multiple of 3. For example, for HE PPDUs, the value of the Length field may be determined to be a multiple of 3 + 1 or a multiple of 3 + 2.

[0082] The data field may include a SERVICE field, a PSDU (Physical layer Service Data Unit), PPDU TAIL bits, and, if necessary, padding bits. Some bits of the SERVICE field may be used for the synchronization of the descrambler at the receiving end. The PSDU corresponds to the MAC PDU defined at the MAC layer and may include data generated / used at the upper layer. The PPDU TAIL bits may be used to return the encoder to the 0 state. The padding bits may be used to align the length of the data field to a predetermined unit.

[0083] The MAC PDU is defined by various MAC frame formats, and the basic MAC frame is composed of a MAC header, a frame body, and an FCS (Frame Check Sequence). The MAC frame is composed of MAC PDUs and may be transmitted / received by the PSDU in the data part of the PPDU format.

[0084] The MAC header includes a Frame Control field, a Duration / ID field, an Address field, etc. The Frame Control field may include control information necessary for frame transmission / reception. The Duration / ID field may be set to the time for transmitting the frame, etc. The address subfield can indicate the receiver address, transmitter address, destination address, and source address of the frame, and some address subfields may be omitted. It includes Sequence Control, QoS Control, and HT Control subfields, and the specific content of each subfield of the MAC header can be referred to the IEEE 802.11 standard document.

[0085] The Null Data PPDU (NDP) format means a PPDU format that does not include a data field. That is, NDP means a frame format that includes the PPDU preamble (i.e., L-STF, L-LTF, L-SIG fields, and, if present, further non-legacy SIG, non-legacy STF, non-legacy LTF) in the general PPDU format and does not include the remaining part (i.e., the data field).

[0086] FIG. 7 is a diagram showing an illustration of a PPDU defined in the IEEE 802.11 standard to which the present disclosure is applicable.

[0087] In standards such as IEEE 802.11a / g / n / ac / ax, various forms of PPDUs are used. The basic PPDU format (IEEE 802.11a / g) includes L-LTF, L-STF, L-SIG, and Data fields. The basic PPDU format can also be referred to as the non-HT PPDU format (FIG. 7(a)).

[0088] The HT PPDU format (IEEE 802.11n) further includes HT-SIG, HT-STF, HT-LFT(s) fields in the basic PPDU format. The HT PPDU format shown in Figure 7(b) can be referred to as the HT-mixed format. An HT-greenfield format PPDU may be further defined, which corresponds to a format composed of HT-GF-STF, HT-LTF1, HT-SIG, one or more HT-LTFs, and a Data field without including L-STF, L-LTF, and L-SIG (not shown).

[0089] An example of the VHT PPDU format (IEEE 802.11ac) further includes VHT SIG-A, VHT-STF, VHT-LTF, and VHT-SIG-B fields in the basic PPDU format (Figure 7(c)).

[0090] An example of the HE PPDU format (IEEE 802.11ax) further includes RL-SIG (Repeated L-SIG), HE-SIG-A, HE-SIG-B, HE-STF, HE-LTF(s), and PE (Packet Extension) fields in the basic PPDU format (Figure 7(d)). Depending on the detailed illustration of the HE PPDU format, some fields may be excluded or their lengths may change. For example, the HE-SIG-B field is included in the HE PPDU format for multi-user (MU), and the HE-SIG-B is not included in the HE PPDU format for single-user (SU). Also, the HE trigger-based (TB) PPDU format does not include the HE-SIG-B, and the length of the HE-STF field may change to 8 us. The HE ER (Extended Range) SU PPDU format does not include the HE-SIG-B field, and the length of the HE-SIG-A field may change to 16 us. For example, RL-SIG may be configured identically to L-SIG. The receiving STA can determine that the received PPDU is an HE PPDU or an EHT PPDU described later based on the presence of RL-SIG.

[0091] The EHT PPDU format may include the EHT MU (multi-user) of FIG. 7(e) and the EHT TB (trigger-based) PPDU of FIG. 7(f). The EHT PPDU format is similar to the HE PPDU format in that it includes an RL-SIG following the L-SIG, but may include a U (universal)-SIG, an EHT-SIG, an EHT-STF, and an EHT-LTF following the RL-SIG.

[0092] The EHT MU PPDU of FIG. 7(e) corresponds to a PPDU that carries one or more data (or PSDUs) for one or more users. That is, the EHT MU PPDU may be used for both SU transmission and MU transmission. For example, the EHT MU PPDU may correspond to a PPDU for one receiving STA or multiple receiving STAs.

[0093] The EHT TB PPDU of FIG. 7(f) omits the EHT-SIG compared to the EHT MU PPDU. A STA that receives a trigger for UL MU transmission (e.g., a trigger frame or TRS (triggered response scheduling)) can perform UL transmission based on the EHT TB PPDU format.

[0094] The L-STF, L-LTF, L-SIG, RL-SIG, U-SIG (Universal SIGNAL), and EHT-SIG fields may be encoded and modulated so that they can also be demodulated and decoded in a legacy STA, and may be mapped based on a defined 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 may be encoded and modulated so that they can be demodulated and decoded by an STA that has successfully decoded a non-legacy SIG (e.g., U-SIG and / or EHT-SIG) and obtained the information contained in the field, and may be mapped based on a defined subcarrier frequency interval (e.g., 78.125 kHz). These can be referred to as EHT modulated fields.

[0095] 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 modulated fields, and the HE-STF, HE-LTF, Data, and PE fields can be referred to as HE modulated fields. Also, in the VHT PPDU format, the L-STF, L-LTF, L-SIG, and VHT-SIG-A fields can be referred to as pre-VHT modulated fields, and the VHT STF, VHT-LTF, VHT-SIG-B, and Data fields can be referred to as VHT modulated fields.

[0096] The U-SIG included in the EHT PPDU format of FIG. 7 may be configured based on, for example, 2 symbols (e.g., 2 consecutive OFDM symbols). Each symbol (e.g., OFDM symbol) for the U-SIG may have a duration of 4 us, and the U-SIG may have an overall duration of 8 us. Each symbol of the U-SIG may be used to transmit 26 bits of information. For example, each symbol of the U-SIG may be transmitted and received based on 52 data tones and 4 pilot tones.

[0097] U-SIG may be configured in units of 20 MHz. For example, when an 80 MHz PPDU is configured, the same U-SIG may be replicated in units of 20 MHz. That is, four identical U-SIGs may be included in the 80 MHz PPDU. When the bandwidth exceeds 80 MHz, for example, for a 160 MHz PPDU, the U-SIG of the first 80 MHz unit and the U-SIG of the second 80 MHz unit may be different from each other.

[0098] In U-SIG, for example, A uncoded bits may be transmitted. The first symbol of U-SIG (for example, U-SIG-1 symbol) may transmit the first X bits of the total A-bit information, and the second symbol of U-SIG (for example, U-SIG-2 symbol) may transmit the remaining Y bits of the total A-bit information. The A-bit information (for example, 52 uncoded bits) may include a CRC field (for example, a 4-bit long field) and a tail field (for example, a 6-bit long field). The tail field may be used to terminate the trellis of the convolutional decoder and may be set to 0, for example.

[0099] The A-bit information transmitted by U-SIG can be distinguished into version-independent bits and version-dependent bits. For example, U-SIG may be included in a new PPDU format (for example, UHR PPDU format) not shown in FIG. 7. In the format of the U-SIG field included in the EHT PPDU format and the format of the U-SIG field included in the UHR PPDU format, the version-independent bits may be the same, and some or all of the version-dependent bits may be different.

[0100] For example, the size of the version-independent bits of U-SIG may be fixed or variable. The version-independent bits may be assigned only to U-SIG-1 symbols, or may be assigned to both U-SIG-1 symbols and U-SIG-2 symbols. The version-independent bits and the version-dependent bits may be called by various names such as the first control bit and the second control bit.

[0101] For example, the version-independent bits of U-SIG may include a 3-bit physical layer version identifier, and this information can indicate the PHY version (e.g., EHT, UHR, etc.) of the transmitted and 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 of the UL / DL flag field is related to DL communication. The version-independent bits of U-SIG may include information regarding the length of the TXOP (transmission opportunity) and information regarding the BSS color ID.

[0102] For example, the version-dependent 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.).

[0103] The information necessary for the transmission and reception of PPDU may be included in U-SIG. For example, U-SIG may further include information regarding the bandwidth, information regarding the MCS method applied to non-legacy SIG (e.g., EHT-SIG or UHR-SIG, etc.), information indicating whether a DCM (dual carrier modulation) method (e.g., reusing the same signal on two subcarriers) is applied to achieve an effect similar to frequency diversity for non-legacy SIG, information regarding the number of symbols used for non-legacy SIG, information regarding whether the non-legacy SIG is generated over the entire bandwidth, etc.

[0104] Some of the information necessary for PPDU transmission and reception may be included in the U-SIG and / or non-legacy SIG (e.g., EHT-SIG or UHR-SIG, etc.). For example, information regarding the type of non-legacy LTF / STF (e.g., EHT-LTF / EHT-STF or UHR-LTF / UHR-STF, etc.), information regarding the length of the non-legacy LTF and the CP (cyclic prefix) length, information regarding the GI (guard interval) applied to the non-legacy LTF, information regarding preamble puncturing applicable to the PPDU, information regarding RU (resource unit) allocation, etc. may be included only in the U-SIG, may be included only in the non-legacy SIG, or may be indicated by a combination of the information included in the U-SIG and the information included in the non-legacy SIG.

[0105] Preamble puncturing can mean the transmission of a PPDU where there is no signal present in one or more frequency units in the PPDU bandwidth. For example, the size of the frequency unit (or the resolution of the preamble puncturing) may be defined as 20 MHz, 40 MHz, etc. For example, preamble puncturing may be applied to a PPDU bandwidth of a predetermined size or more.

[0106] In the example of FIG. 7, non-legacy SIGs such as HE-SIG-B and EHT-SIG may include control information for the receiving STA. The non-legacy SIG may be transmitted in at least one symbol, and one symbol may have a length of 4 us. Information regarding the number of symbols used for the EHT-SIG may be included in a previous SIG (e.g., HE-SIG-A, U-SIG, etc.).

[0107] Non-legacy SIGs such as HE-SIG-B and EHT-SIG may include a common field and user-specific fields. The common field and user-specific fields may be coded separately.

[0108] In some cases, the common field may be omitted. For example, the common field may be omitted in a compression mode where non-OFDMA (orthogonal frequency multiple access) is applied, and multiple STAs can receive a PPDU (e.g., the data field of the PPDU) in the same frequency band. In a non-compression mode where OFDMA is applied, multiple users can receive a PPDU (e.g., the data field of the PPDU) in individual frequency bands.

[0109] The number of user-specific fields may be determined based on the number of users. One user block field may include a maximum of two user fields. Each user field may be related to MU-MIMO allocation or non-MU-MIMO allocation.

[0110] The common field may include CRC bits and Tail bits. The length of the CRC bits may be determined to be 4 bits, and the length of the Tail bits may be determined to be 6 bits and may be set to 000000. The common field may include RU allocation information. The RU allocation information may include information about the location of the RUs allocated to multiple users (i.e., multiple receiving STAs).

[0111] An RU may include a plurality of subcarriers (or tones). An RU may be used when transmitting signals to a plurality of STAs based on the OFDMA technique. Also, an RU may be defined even when transmitting a signal to one STA. Resources may be allocated in units of RUs for non-legacy STF, non-legacy LTF, and Data fields.

[0112] RUs of applicable sizes may be defined by the PPDU bandwidth. The RUs may be defined to be the same or different for the applicable PPDU formats (e.g., HE PPDU, EHT PPDU, UHR PPDU, etc.). For example, in the case of an 80 MHz PPDU, the RU arrangements of the HE PPDU and the EHT PPDU may be different from each other. The size of the applicable RUs, the number of RUs, the RU positions, the DC (direct current) subcarrier positions and number, the null subcarrier positions and number, the guard subcarrier positions and number, etc. for each PPDU bandwidth can be referred to as a tone-plan. For example, the tone-plan for a wide bandwidth may be defined in the form of multiple repetitions of the tone-plan for a low bandwidth.

[0113] RUs of various sizes may be defined such as 26-tone RU, 52-tone RU, 106-tone RU, 242-tone RU, 484-tone RU, 996-tone RU, 2×996-tone RU, 4×996-tone RU, etc. An MRU (multiple RU) is distinguished from a plurality of individual RUs and corresponds to a group of subcarriers composed of a plurality of RUs. For example, one MRU may be defined as 52 + 26 tones, 106 + 26 tones, 484 + 242 tones, 996 + 484 tones, 996 + 484 + 242 tones, 2×996 + 484 tones, 3×996 tones, or 3×996 + 484 tones. Also, the plurality of RUs constituting one MRU may or may not be continuous in the frequency domain.

[0114] The specific size of the RU may be reduced or expanded. Therefore, in the present disclosure, the specific size of each RU (i.e., the number of corresponding tones) is illustrative rather than restrictive. Also, in the present disclosure, within a given bandwidth (e.g., 20, 40, 80, 160, 320 MHz,...), the number of RUs may vary depending on the size of the RU.

[0115] In the PPDU format of FIG. 7, the names of the respective fields are illustrative and the scope of the present disclosure is not limited by the names. Also, the examples of the present disclosure may be applied to new PPDU formats in which some fields are excluded and / or some fields are added based on the PPDU format illustrated in FIG. 7 in addition to the PPDU format illustrated in FIG. 7.

[0116] FIG. 8 is a diagram showing an exemplary format of a trigger frame to which the present disclosure is applicable.

[0117] The trigger frame can allocate resources for one or more TB PPDU transmissions and request TB PPDU transmissions. The trigger frame may also include other information required by the STA that transmits the TB PPDU in response thereto. The trigger frame may include a common info field and a user info list field in the frame body.

[0118] The common info field may include information that is commonly applied to one or more TB PPDU transmissions requested by the trigger frame, such as trigger type, UL length, presence or absence of a subsequent trigger frame (e.g., More TF), presence or absence of a CS (channel sensing) requirement, UL BW (bandwidth), etc. FIG. 8 illustrates the EHT variant common info field format.

[0119] The 4-bit size trigger type subfield may have values from 0 to 15. Among them, the values 0, 1, 2, 3, 4, 5, 6, and 7 of the trigger type subfield are defined as corresponding to basic, BFRP (Beamforming Report Poll), MU-BAR (multi user-block acknowledgement request), MU-RTS (multi user-request to send), BSRP (Buffer Status Report Poll), GCR (groupcast with retries) MU-BAR, BQRP (Bandwidth Query Report Poll), and NFRP (NDP Feedback Report Poll) respectively, and the values 8 to 15 are defined as reserved.

[0120] Among the common information, the trigger dependent common info subfield may include information selectively included based on the trigger type.

[0121] A special user info field may be included in the trigger frame. The special user info field does not include user-specific information and includes extended common information not provided in the common information field.

[0122] The user information list includes one or more user info fields. In FIG. 8, the EHT variant user information field format is illustrated.

[0123] The AID12 subfield basically indicates that it is a user information field for the STA having the said AID. Additionally, when the AID12 field has a predetermined specific value, it may be utilized for other purposes such as allocating a random access (RA)-RU or being configured in the form of a special user info field. The special user info field is a user information field that does not contain user-specific information but includes extended common information not provided in the common information field. For example, the special user info field may be identified by an AID12 value of 2007, and the special user info field flag subfield in the common information field can indicate whether the special user info field is included or not.

[0124] The RU allocation subfield can indicate the size and position of the RU / MRU. For this purpose, the RU allocation subfield may be analyzed together with the PS160 (primary / secondary 160MHz) subfield of the user information field, the UL BW subfield of the common information field, etc.

[0125] Furthermore, in the present disclosure, the tone plan may be related to the rules for determining the size and / or position of the resource unit (RU). Hereinafter, the tone plan applied to the HE PPDU (i.e., the PPDU based on the IEEE 802.11ax standard) will be described as an example. Specifically, the RU size / position applied to the HE PPDU and the control information related to the RU applied to the HE PPDU will be described.

[0126] In the present disclosure, the control information related to the RU (or the control information related to the tone plan) may include control information regarding the size, position of the RU, information of the user STA assigned to a specific RU, the frequency bandwidth for the PPDU in which the RU is included, and / or the modulation method applied to the specific RU. The control information related to the RU may be included in the SIG field. For example, the control information related to the RU may be included in the HE-SIG-B field. That is, in the process of generating the transmitted PPDU, the transmitting STA can include the control information for the RU included in the PPDU in the HE-SIG-B field. Also, the receiving STA receives the HE-SIG-B included in the received PPDU, obtains the control information included in the HE-SIG-B, determines whether there is an RU assigned to the receiving STA, and can decode the assigned RU based on the HE-SIG-B.

[0127] In an existing wireless LAN system (for example, the IEEE 802.11ax standard), the HE-STF, HE-LTF, and data fields may be configured in units of RUs. That is, when a first RU for a first receiving STA is set, the STF / LTF / data fields for the first receiving STA may be transmitted and received by the first RU.

[0128] In an existing wireless LAN system (for example, the IEEE 802.11ax standard), a PPDU for one receiving STA (i.e., an SU PPDU) and a PPDU for multiple receiving STAs (i.e., an MU PPDU) may be defined separately, and tone plans for each may be defined separately.

[0129] A (aggregate)-MPDU structure

[0130] As shown in FIG. 9, an A-MPDU may include a sequence of one or more A-MPDU sub-frames and EOF (end of frame) padding. Each A-MPDU sub-frame may include an MPDU delimiter and an MPDU. As shown in FIG. 9, the MPDU may be arranged to follow the MPDU delimiter.

[0131] Padding octets may be added to each of the non-final A-MPDU sub-frames of the A-MPDU so that the sub-frame length may be a multiple of 4 octets. The content of the octets need not be specified.

[0132] The EOF padding sub-frame sub-field may include zero or more EOF padding sub-frames. An EOF padding sub-frame may mean an A-MPDU sub-frame in which the MPDU length field is 0 and the EOF field is 1. The A-MPDU pre-EOF padding does not include the EOF padding field and can indicate the content of the A-MPDU.

[0133] In an HT PPDU, the maximum length of an A-MPDU may be 65,535 octets. In a DMG PPDU, the maximum length of an A-MPDU may be 262,143 octets. In a VHT PPDU, the maximum length of the A-MPDU pre-EOF padding may be 1,048,575 octets. In a HE PPDU, the maximum length of the A-MPDU pre-EOF padding may be 6,500,631 octets. The length of an A-MPDU directed to a specific STA may be further restricted.

[0134] As shown in FIG. 9, the MPDU delimiter field may include an EOF / Tag sub-field, an MPDU length sub-field, a CRC, a Delimiter signature sub-field, etc.

[0135] As an example, the EOT / Tag subfield can indicate the end of the frame when the MPDU length field is 0. In an A-MPDU subframe where the MPDU length subfield is 0 and is used to pad an A-MPDU in a VHT or HE PPDU, the EOT / Tag field may be set to 1. The MPDU delimiter of the S-MPDU may be set to 1.

[0136] As an example, the EOT / Tag subfield can indicate the presence or absence of a tag / untagged when the MPDU length subfield is not 1.

[0137] The MPDU length subfield can indicate the length of the MPDU in octet units. If no MPDU exists, the MPDU length field value may be set to 0. As shown in FIG. 9, when transmitted by a non-DMG STA, the format of the MPDU length field may be configured. The MPDU length subfield may include the lower 12 bits of the MPDU length. In a VHT or HE PPDU, the MPDU length High subfield may include the upper 2 bits of the MPDU length. In an HT PPDU, the MPDU length high subfield may be reserved.

[0138] And the Delimiter signature field is a pattern used to detect the MPDU delimiter during scanning for the MPDU delimiter.

[0139] (A-)MPDU length-related capability information may be exchanged between STAs. As an example, the (A-)MPDU length-related capability information may be exchanged by a VHT capability information field, an S1G capability information field, an HE MAC capability information field, and / or an HE6GHz band capability element.

[0140] Each capability information field / element can indicate the maximum (A-)MDPU length that the STA can receive / support and / or the exponent for the maximum (A-)MPDU length.

[0141] A-MPDU operation in HE PPDU

[0142] To indicate the value of the maximum length of A-MPDUs within an HE PPDU, the HE MAC Capabilities Information field may use the Length Exponent Extension subfield.

[0143] An HE STA that transmits a Class 1 frame or a Class 2 frame in an HE PPDU can transmit the frame as an S-MPDU. An HE STA that transmits a VHT Capability element, an HT Capability element, or an HE6GHz Band Capability element and an HE Capability element with a maximum A-MPDU length exponent extension field of 0 can support the reception of an A-MPDU pre-EOF padding of the maximum length.

[0144] An HE STA that transmits a VHT Capability element and an HE Capability element with a maximum A-MPDU length exponent extension subfield greater than 0 can support the reception of an HE PPDU with an A-MPDU pre-EOF padding, except that the maximum length of the A-MPDU pre-EOF padding should be the same as min(2(20 + maximum A-MPDU length exponent extension)).

[0145] An HE STA that sets the maximum A-MPDU exponent element extension subfield of the HE Capability element to a value greater than 0 can set the maximum A-MPDU length exponent subfield of the VHT Capability element to 7.

[0146] Except that the maximum length of the A-MPDU pre-EOF padding should be the same as 2(16 + maximum A-MPDU length exponent extension)-1, an HE STA that does not transmit the VHT capability element but transmits the HT capability element and the HE capability element with the maximum A-MPDU length exponent extension subfield greater than 0 can support the A-MPDU pre-EOF padding in the HE PPDU when receiving.

[0147] An HE STA that sets the maximum A-MPDU length exponent extension subfield of the HE capability element to a value greater than 0 can set the maximum A-MPDU length exponent subfield of the HT capability element to 3.

[0148] Here, an HE STA that is a VHT STA can transmit the VHT capability element, and an HE STA that is not a VHT STA does not have to transmit the VHT capability element.

[0149] An HE STA that transmits the HE6GHz Band capability element and the HE capability element with the maximum A-MPDU length exponent extension subfield greater than 0 can support the reception of the A-MPDU pre-EOF padding in the HE PPDU.

[0150] An HE STA shall not transmit the A-MPDU of the HE PPDU to a STA that exceeds the maximum A-MPDU length capability indicated by the HE capability, VHT capability, and HT capability elements received from the receiving STA.

[0151] When the VHT capability element is received from the receiving STA, the maximum A-MPDU length capability may be derived from the maximum A-MPDU length exponent extension subfield of the HE capability element and the maximum A-MPDU length exponent subfield of the VHT capability element.

[0152] Otherwise, the maximum A-MPDU length capability may be derived from the maximum A-MPDU length exponent subfield of the HE capability element and the maximum A-MPDU length exponent subfield of the HT HE capability element or the HE6GHz Band capability element.

[0153] Transmission and reception method of A-MPDU including two or more trigger frames

[0154] In a basic wireless LAN system, an A-MPDU may include one or more trigger frames, and all of the one or more trigger frames may include the same content.

[0155] In the present disclosure, when one of two or more trigger frames includes RU allocation related information for a primary channel and another frame includes RU allocation related information for a secondary channel, the configuration of the A-MPDU and its transmission and reception method will be described.

[0156] According to the present disclosure, by transmitting, by an AP, an A-MPDU including two or more trigger frames to a non-AP STA, RU allocation information for a primary channel and a secondary channel may be set simultaneously.

[0157] Here, two or more trigger frames may be regarded as one set, and separate trigger frames including the same content as each of the two or more trigger frames may be aggregated on the A-MPDU.

[0158] FIG. 10 is a diagram for explaining an operation performed by a first STA according to an embodiment of the present disclosure.

[0159] In FIGS. 10 and 11, the first STA may be a non-AP STA and the second STA may be an AP, but is not limited thereto. The first STA and the second STA may each be either a non-AP STA or an AP.

[0160] The first STA can receive an aggregated (A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame from the second STA (S1010).

[0161] Here, the second trigger frame may follow the first trigger frame on the A-MPDU. That is, the first trigger frame may be arranged ahead of the second trigger frame.

[0162] The first trigger frame may include first information indicating at least one resource unit (RU) within the primary channel bandwidth, and the second trigger frame may include second information indicating at least one RU within the secondary channel bandwidth.

[0163] That is, the information included in the two trigger frames constituting one A-MPDU may be different from each other. For example, the first trigger frame may include information related to the primary channel bandwidth, and the second trigger frame may include information related to the secondary channel bandwidth.

[0164] As an example of the present disclosure, assume that the overall bandwidth (i.e., the size of the allowed bandwidth) is 640 MHz.

[0165] At this time, 320 MHz may be indicated as the primary channel bandwidth by the first information. That is, the first information can indicate that 320 MHz is allocated to the first STA as the primary channel bandwidth. And the first information may be indicated by the PS (primary secondary) 320 subfield included in the first trigger frame. The PS320 subfield value included in the first trigger frame may be set to 1.

[0166] Based on the bandwidth of the second trigger frame being 80 MHz, 160 MHz, or 320 MHz, the second information may indicate 80 MHz, 160 MHz, or 320 MHz as the secondary channel bandwidth. The second information may be indicated by the PS320 subfield included in the second trigger frame. The PS320 subfield value included in the second trigger frame may be set to 0.

[0167] As yet another example of the present disclosure, assume that the overall bandwidth (i.e., the size of the allowable bandwidth) is 320 MHz. The overall bandwidth may be set / indicated by the first STA / second STA, or may be predefined.

[0168] At this time, 160 MHz may be indicated as the primary channel bandwidth by the first information. That is, the first information can indicate that 160 MHz is allocated to the first STA as the primary channel bandwidth. And the first information may be indicated by the PS160 subfield included in the first trigger frame. The PS160 subfield value included in the first trigger frame may be set to 1.

[0169] Based on the bandwidth of the second trigger frame being 80 MHz or 160 MHz, the second information may indicate 80 MHz or 160 MHz as the secondary channel bandwidth. The second information may be indicated by the PS160 subfield included in the second trigger frame. The PS160 subfield value included in the second trigger frame may be set to 0.

[0170] And the first trigger frame and the second trigger frame may each include an EHT variant common information field. The EHT variant common information field may include a PS320 subfield or a PS160 subfield.

[0171] The PS320 subfield or the PS160 subfield can use 1 bit of the reserved fields of the EHT variant common information field. As an example, the PS320 subfield or the PS160 subfield may be set on the 64th bit (B63) of the EHT variant common information field.

[0172] The first STA can perform uplink transmission based on the first trigger frame and the second trigger frame (S1020).

[0173] As an example, the first STA can confirm the resource units indicated / assigned by the primary channel and the secondary channel respectively indicated by the first trigger frame and the second trigger frame, and transmit a PPDU to the second STA based on the indicated / assigned resource units.

[0174] The method performed by the first STA described in the example of FIG. 10 may be performed by the first device 100 of FIG. 1. For example, one or more processors 102 of the first device 100 of FIG. 1 may be configured to receive an A-MPDU including the first trigger frame and the second trigger frame from the second STA via one or more transceivers 106. One or more processors 102 may be configured to perform uplink transmission based on the first trigger frame and the second trigger frame via one or more transceivers 106.

[0175] Note that one or more memories 104 of the first device 100 can store instructions for performing the method described in the example of FIG. 10 when executed by one or more processors 102.

[0176] FIG. 11 is a diagram for explaining operations performed by a second STA according to an embodiment of the present disclosure.

[0177] The second STA can transmit an A-MPDU including a first trigger frame and a second trigger frame to the first STA (S1110).

[0178] The second STA can configure the A-MPDU with two trigger frames by the entire bandwidth (e.g., 640 MHz or 320 MHz). The second STA can configure the A-MPDU such that the first trigger frame is located in front of the second trigger frame.

[0179] The information included in each trigger frame has been described with reference to FIG. 10, and overlapping descriptions thereof are omitted.

[0180] The second STA can perform uplink reception based on the first trigger frame and the second trigger frame (S1120).

[0181] The method performed by the second STA described in the example of FIG. 11 may be performed by the second device 200 of FIG. 1. For example, one or more processors 202 of the second device 200 of FIG. 1 may be set to transmit an A-MPDU including a first trigger frame and a second trigger frame to the first STA via one or more transceivers 206. One or more processors 202 may be set to perform uplink reception based on the first trigger frame and the second trigger frame via one or more transceivers 206.

[0182] Note that one or more memories 204 of the second device 200 can store instructions for performing the method described in the example of FIG. 11 when executed by one or more processors 202.

[0183] Hereinafter, a method for transmitting and receiving an A-PPDU composed of two or more trigger frames will be specifically described.

[0184] Example 1

[0185] Example 1 relates to the operation of an AP transmitting an A-MPDU containing two trigger frames to a STA in a 640 MHz bandwidth (i.e., when the allowable channel bandwidth is 640 MHz) and the configuration of the A-MPDU.

[0186] As an example, as shown in FIG. 12(a), when the AP constructs an A-MPDU containing two trigger frames, among the two trigger frames, the trigger frame located in the front (hereinafter, "first trigger frame") 1210 may be assumed to be used when allocating a primary 320 MHz RU. That is, as shown in FIG. 12(a), the AP can construct an EHT MU PPDU that constructs an A-MPDU using two trigger frames.

[0187] At this time, the trigger frame (hereinafter, "second trigger frame") 1220 following the first trigger frame 1210 may be used when allocating an RU assigned to the secondary channel bandwidth.

[0188] In a basic wireless LAN system, the UL BW subfield in the trigger frame (i.e., the field indicating the bandwidth for PPDU transmission and reception requested by the trigger frame) does not need to distinguish between the primary channel bandwidth and the secondary bandwidth.

[0189] Therefore, as an example of the present disclosure, as shown in FIG. 12(a), in order to indicate an RU of the secondary channel bandwidth, 1 bit of the reserved fields of the EHT variant common information field included in the second trigger frame 1220 may be used as the PS320 subfield.

[0190] That is, as shown in FIG. 12(a), the trigger frame of the A-MPDU can use the value of the PS320 subfield to indicate the channel bandwidth of the RU assigned to the STA.

[0191] For example, when the PS320 subfield value is set to 1 (or 0), this can mean that the channel bandwidth of the RU assigned to the STA is the primary 320 MHz. And when the PS320 subfield value is set to 0 (or 1), this can mean that the channel bandwidth of the RU assigned to the STA is the secondary 320 MHz.

[0192] The A-MPDU formats shown in FIGS. 12(b) to 12(d) are based on the configuration of FIG. 9(a). As shown in FIGS. 12(b) to 12(d), the first trigger frame may include information for the primary channel bandwidth of 320 MHz. Accordingly, it may be set to 1 (or 0), which is the PS320 subfield value of the first trigger frame, and the first trigger frame may include bandwidth information for 320 MHz.

[0193] As an example, FIG. 12(b) is an A-MPDU format when the bandwidth of the second trigger frame is 80 MHz. At this time, the PS320 subfield value of the first trigger frame may be set to 1 (i.e., the primary channel bandwidth of 320 MHz is indicated / assigned), and the PS320 subfield value of the second trigger frame may be set to 0 (i.e., the secondary channel bandwidth of 80 MHz is indicated / assigned). That is, the second trigger frame may include information indicating that the secondary 80 MHz is assigned.

[0194] As another example, FIG. 12(c) is an A-MPDU format when the bandwidth of the second trigger frame is 160 MHz. At this time, the PS320 subfield value of the first trigger frame may be set to 1 (i.e., the primary channel bandwidth of 320 MHz is indicated / assigned), and the PS320 subfield value of the second trigger frame may be set to 0 (i.e., the secondary channel bandwidth of 160 MHz is indicated / assigned). That is, the second trigger frame may include information indicating that the secondary 160 MHz is assigned.

[0195] As yet another example, (d) of FIG. 12 shows an A-MPDU format when the bandwidth of the second trigger frame is 320 MHz. At this time, the PS320 subfield value of the first trigger frame may be set to 1 (i.e., the primary channel bandwidth of 320 MHz is indicated / assigned), and the PS320 subfield value of the second trigger frame may be set to 0 (i.e., the secondary channel bandwidth of 320 MHz is indicated / assigned). That is, the second trigger frame may include information indicating the assignment of secondary 320 MHz.

[0196] Example 2

[0197] Embodiment 2 relates to the operation of an AP transmitting an A-MPDU including two trigger frames to a STA at a 320 MHz bandwidth (i.e., when the allowable channel bandwidth is 320 MHz) and the configuration of the A-MPDU.

[0198] The A-MPDU may be configured by the PS160 subfield included in the EHT variant user field of each trigger frame. The first trigger frame (i.e., the trigger frame located at the forefront on the A-MPDU) may include information regarding the primary channel bandwidth of 160 MHz.

[0199] As yet another example, (e) of FIG. 12 shows an A-MPDU format when the bandwidth of the second trigger frame is 80 MHz. At this time, the PS160 subfield value of the first trigger frame may be set to 1 (i.e., the primary channel bandwidth of 160 MHz is indicated / assigned), and the PS160 subfield value of the second trigger frame may be set to 0 (i.e., the secondary channel bandwidth of 80 MHz is indicated / assigned). That is, the second trigger frame may include information indicating the assignment of secondary 80 MHz.

[0200] As yet another example, FIG. 12(f) shows an A-MPDU format when the bandwidth of the second trigger frame is 160 MHz. At this time, the PS160 subfield value of the first trigger frame may be set to 1 (i.e., the primary channel bandwidth of 160 MHz is indicated / assigned), and the PS160 subfield value of the second trigger frame may be set to 0 (i.e., the secondary channel bandwidth of 160 MHz is indicated / assigned). That is, the second trigger frame may include information indicating the assignment of secondary 160 MHz.

[0201] In FIGS. 12(e) and 12(f), it is assumed that there is no PS320 subfield in each trigger frame. As an example, when the allowable channel bandwidth is 320 MHz and each trigger frame includes a PS320 subfield, the PS320 subfield values of the first trigger frame and the second trigger frame may both be set to 1.

[0202] The embodiments described above are those in which the components and features of the present disclosure are combined in a predetermined form. Each component or feature should be considered as optional unless specifically and explicitly mentioned. Each component or feature may be implemented in a form that does not combine with other components or features. Also, it is possible to configure embodiments of the present disclosure by combining some components and / or features. The order of operations described in the embodiments of the present disclosure may be changed. Some components or features of one embodiment may be included in other embodiments, or may be replaced with corresponding components or features of other embodiments. It is obvious that claims without an explicit citation relationship in the claims can be combined to form embodiments, or included as new claims by amendment after filing.

[0203] It will be apparent to those skilled in the art that the present disclosure can be embodied in other specific forms without departing from the essential features thereof. Therefore, the above detailed description should not be construed in any limiting sense, but rather should be considered as exemplary. The scope of the present disclosure should be determined by a reasonable interpretation of the appended claims, and any modifications within the equivalent scope of the present disclosure are included in the scope of the present disclosure.

[0204] The scope of the present disclosure includes software or machine-executable instructions (e.g., operating systems, applications, firmware, programs, etc.) that cause an apparatus or computer to perform operations according to various example methods, and non-transitory computer-readable media on which such software or instructions are stored and executable on the apparatus or computer. Instructions available for programming a processing system to perform the features described in the present disclosure may be stored on or in a storage medium or computer-readable storage medium, and a computer program product including such a storage medium may be used to embody the features described in the present disclosure. The storage medium can include, but is not limited to, high-speed random access memory such as DRAM, SRAM, DDR RAM, or other random access solid-state memory devices, and can include non-volatile memory such as one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid-state storage devices. The memory may optionally include one or more storage devices located remotely from the processor. The memory or, alternatively, the non-volatile memory device within the memory includes a non-transitory computer-readable storage medium. The features described in the present disclosure may be stored on any one of the machine-readable media, integrated into software and / or firmware that can control the hardware of the processing system and interact with other mechanisms by which the processing system utilizes the results according to the examples of the present disclosure. Such software or firmware can include, but is not limited to, application code, device drivers, operating systems, and execution environments / containers. 〔Industrial Applicability〕

[0205] The method proposed in the present disclosure has been mainly described with an example applied to an IEEE 802.11-based system, but it can also be applied to various wireless LANs or wireless communication systems other than the IEEE 802.11-based system.

[0206] [Claims at the time of international filing] [Claim 1] A method performed by a first station (STA: station) in a wireless LAN system, receiving an aggregated (aggregate: A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame from a second STA; performing uplink transmission based on the first trigger frame and the second trigger frame, comprising: the first trigger frame includes first information indicating at least one resource unit (RU) within a primary channel bandwidth; the second trigger frame includes second information indicating at least one RU within a secondary channel bandwidth. A method. [Claim 2] The method according to claim 1, wherein the second trigger frame follows the first trigger frame on the A-MPDU. [Claim 3] Based on the total bandwidth being 640 MHz, 320 MHz is indicated as the primary channel bandwidth by the first information; The method according to claim 1, wherein the first information is indicated by a PS (primary secondary) 320 subfield included in the first trigger frame. [Claim 4] Based on the bandwidth of the second trigger frame being 80 MHz, 160 MHz, or 320 MHz, 80 MHz, 160 MHz, or 320 MHz is indicated as the secondary channel bandwidth by the second information; The method according to claim 3, wherein the second information is indicated by a PS320 subfield included in the second trigger frame. [Claim 5] The method according to claim 4, wherein the PS320 subfield value included in the first trigger frame is set to 1, and the PS320 subfield value included in the second trigger frame is set to 0. [Claim 6] Based on the overall bandwidth being 320 MHz, 160 MHz is indicated as the primary channel bandwidth by the first information. The method according to claim 1, wherein the first information is indicated by the PS160 subfield included in the first trigger frame. [Claim 7] Based on the bandwidth of the second trigger frame being 80 MHz or 160 MHz, the second information indicates 80 MHz or 160 MHz as the secondary channel bandwidth. The method according to claim 6, wherein the second information is indicated by the PS160 subfield included in the second trigger frame. [Claim 8] The method according to claim 6, wherein the PS160 subfield value included in the first trigger frame is set to 1, and the PS160 subfield value included in the second trigger frame is set to 0. [Claim 9] Each of the first trigger frame and the second trigger frame includes an EHT (extremely high throughput) variant common information field. The method according to claim 1, wherein the EHT variant common information field includes a PS320 subfield or a PS160 subfield. [Claim 10] The method according to claim 9, wherein the PS320 subfield or the PS160 subfield is set on the 64th bit (B63) of the EHT variant common information field. [Claim 11] A first station (STA: station) operating in a wireless LAN system, One or more transceivers, One or more processors coupled to the one or more transceivers, and comprising: The one or more processors are configured to receive, from a second STA, an aggregated (A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame via the one or more transceivers, and perform uplink transmission based on the first trigger frame and the second trigger frame. The first trigger frame includes first information indicating at least one resource unit (RU) within a primary channel bandwidth. The second trigger frame includes second information indicating at least one resource unit (RU) within a secondary channel bandwidth, a first STA. [Claim 12] A method performed by a second station (STA: station) in a wireless LAN system, comprising transmitting an aggregated (A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame to a first STA, and performing uplink reception based on the first trigger frame and the second trigger frame. The first trigger frame includes first information indicating at least one resource unit (RU) within a primary channel bandwidth. The second trigger frame includes second information indicating at least one resource unit (RU) within a secondary channel bandwidth, a method. [Claim 13] A second station (STA: station) operating in a wireless LAN system, one or more transceivers, One or more processors coupled to the one or more transceivers, and comprising: The one or more processors are: Transmitting an aggregated (A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame to a first STA; Configured to perform uplink reception based on the first trigger frame and the second trigger frame; The first trigger frame includes first information indicating at least one resource unit (RU) within a primary channel bandwidth; The second trigger frame includes second information indicating at least one resource unit (RU) within a secondary channel bandwidth, a second STA. [[Claim 14]] A processing device configured to control a first station (STA: station) operating in a wireless LAN system, One or more processors; One or more computer memories operably coupled to the one or more processors and storing instructions for performing operations based on execution by the one or more processors; The operations are: Receiving, from a second STA, an aggregated (A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame; Performing uplink transmission based on the first trigger frame and the second trigger frame; The first trigger frame includes first information indicating at least one resource unit (RU) within a primary channel bandwidth; The second trigger frame is a processing device including second information indicating at least one resource unit (RU) within a secondary channel bandwidth. [Claim 15] One or more non-transitory computer-readable media storing one or more instructions, wherein the one or more instructions are executed by one or more processors to cause a device operating in a wireless LAN system to receive an aggregated (A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame from a second station (STA: station), and perform uplink transmission based on the first trigger frame and the second trigger frame. The first trigger frame includes first information indicating at least one resource unit (RU) within a primary channel bandwidth, and the second trigger frame is a computer-readable medium including second information indicating at least one resource unit (RU) within a secondary channel bandwidth.

Claims

1. A method performed by a first station (STA) in a wireless LAN system, comprising: receiving, from a second STA, an aggregated (A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame; performing uplink transmission based on the first trigger frame and the second trigger frame, wherein the first trigger frame includes first information indicating at least one resource unit (RU) within a primary channel bandwidth; and the second trigger frame includes second information indicating at least one RU within a secondary channel bandwidth.

2. The method according to claim 1, wherein the second trigger frame follows the first trigger frame on the A-MPDU.

3. Based on the total bandwidth being 640 MHz, 320 MHz is indicated as the primary channel bandwidth by the first information; the method according to claim 1, wherein the first information is indicated by a PS (primary secondary) 320 subfield included in the first trigger frame.

4. Based on the bandwidth of the second trigger frame being 80 MHz, 160 MHz, or 320 MHz, 80 MHz, 160 MHz, or 320 MHz is indicated as the secondary channel bandwidth by the second information; the method according to claim 3, wherein the second information is indicated by a PS320 subfield included in the second trigger frame.

5. The method according to claim 4, wherein the PS320 subfield value included in the first trigger frame is set to 1, and the PS320 subfield value included in the second trigger frame is set to 0.

6. Based on the total bandwidth being 320 MHz, 160 MHz is indicated as the primary channel bandwidth by the first information; the method according to claim 1, wherein the first information is indicated by a PS160 subfield included in the first trigger frame.

7. Based on the bandwidth of the second trigger frame being 80 MHz or 160 MHz, the second information indicates 80 MHz or 160 MHz as the secondary channel bandwidth. The method according to claim 6, wherein the second information is indicated by a PS160 subfield included in the second trigger frame. **Claim 8** The method according to claim 6, wherein the PS160 subfield value included in the first trigger frame is set to 1, and the PS160 subfield value included in the second trigger frame is set to 0. **Claim 9** Each of the first trigger frame and the second trigger frame includes an EHT (extremely high throughput) variant common information field. The method according to claim 1, wherein the EHT variant common information field includes a PS320 subfield or a PS160 subfield. **Claim 10** The method according to claim 9, wherein the PS320 subfield or the PS160 subfield is set on the 64th bit (B63) of the EHT variant common information field. **Claim 11** A first station (STA: station) operating in a wireless LAN system, One or more transceivers, One or more processors coupled to the one or more transceivers, and is configured to: The one or more processors Receive an aggregated (A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame from a second STA via the one or more transceivers, Perform uplink transmission based on the first trigger frame and the second trigger frame. The first trigger frame includes first information indicating at least one resource unit (RU) within a primary channel bandwidth. The second trigger frame includes second information indicating at least one resource unit (RU) within a secondary channel bandwidth. **Claim 12** A method performed by a second station (STA: station) in a wireless LAN system. Transmitting an aggregated (A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame to a first STA; Performing uplink reception based on the first trigger frame and the second trigger frame, and comprising: The first trigger frame includes first information indicating at least one resource unit (RU) within a primary channel bandwidth; The second trigger frame includes second information indicating at least one resource unit (RU) within a secondary channel bandwidth, a method.

13. A second station (STA: station) operating in a wireless LAN system, One or more transceivers; One or more processors coupled to the one or more transceivers, and comprising: The one or more processors are: Transmitting an aggregated (A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame to a first STA; Configured to perform uplink reception based on the first trigger frame and the second trigger frame; The first trigger frame includes first information indicating at least one resource unit (RU) within a primary channel bandwidth; The second trigger frame includes second information indicating at least one resource unit (RU) within a secondary channel bandwidth, a second STA.

14. A processing device configured to control a first station (STA: station) operating in a wireless LAN system, One or more processors; One or more computer memories operably coupled to the one or more processors and storing instructions for performing operations based on being executed by the one or more processors, and comprising: The operations are: Receiving, from a second STA, an aggregated (A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame; Performing uplink transmission based on the first trigger frame and the second trigger frame; The first trigger frame includes first information indicating at least one resource unit (RU) within a primary channel bandwidth; The second trigger frame includes second information indicating at least one resource unit (RU) within a secondary channel bandwidth, a processing device.

15. One or more non-transitory computer-readable media storing one or more instructions, The one or more instructions are executed by one or more processors, and a device operating in a wireless LAN system Receives, from a second station (STA), an aggregated (A)-MPDU (medium access control protocol data unit) including a first trigger frame and a second trigger frame, Is controlled to perform uplink transmission based on the first trigger frame and the second trigger frame, The first trigger frame includes first information indicating at least one resource unit (RU) within a primary channel bandwidth; The second trigger frame includes second information indicating at least one resource unit (RU) within a secondary channel bandwidth, a computer-readable medium.

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