Method and apparatus for providing feedback information via trigger frame in wireless LAN system

Abstract

Disclosed are a method and an apparatus for providing feedback information via a trigger frame in a wireless LAN system. A method, according to one aspect of the present disclosure, may comprise the steps of: generating, by a first station (STA), a trigger frame including at least one first user information field including feedback information; and transmitting, by the first STA, a physical layer protocol data unit (PPDU) including the trigger frame to a second STA. The first user information field may include a feedback type field and a feedback information field.

Description

Method and device for providing feedback information through trigger frames in a wireless LAN system

[0001] The present disclosure relates to a method and device for providing feedback information through a trigger frame in a wireless local area network (WLAN) system.

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

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

[0004] The technical problem of the present disclosure is to provide a method and device for providing feedback information through a trigger frame in a wireless LAN system.

[0005] The technical problems to be achieved in the present disclosure are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present disclosure belongs from the description below.

[0006] A method according to one aspect of the present disclosure may include: generating, by a first station (STA), a trigger frame including at least one first user information field including feedback information; and transmitting, by the first STA, a physical layer protocol data unit (PPDU) including the trigger frame to a second STA. The first user information field may include a feedback type field and a feedback information field.

[0007] A method according to an additional aspect of the present disclosure may include: receiving, by a second station (STA), from a first STA a trigger frame including at least one first user information field including feedback information; and transmitting, by the second STA, a response frame responsive to the trigger frame to the first STA. The first user information field may include a feedback type field and a feedback information field.

[0008] According to the present disclosure, a method and device for providing feedback information through a trigger frame in a wireless LAN system can be provided.

[0009] The effects that can be obtained from the present disclosure are not limited to the effects mentioned above, and other effects that are not mentioned will be clearly understood by a person having ordinary skill in the art to which the present disclosure pertains from the description below.

[0010] The accompanying drawings, which are incorporated in and are part of the detailed description to aid in understanding the present disclosure, provide embodiments of the present disclosure and, together with the detailed description, describe the technical features of the present disclosure.

[0011] FIG. 1 illustrates a block diagram of a wireless communication device according to one embodiment of the present disclosure.

[0012] FIG. 2 is a diagram showing an exemplary structure of a wireless LAN system to which the present disclosure can be applied.

[0013] FIG. 3 is a diagram for explaining a link setup process to which the present disclosure can be applied.

[0014] FIG. 4 is a diagram for explaining a backoff process to which the present disclosure can be applied.

[0015] FIG. 5 is a diagram for explaining a CSMA / CA-based frame transmission operation to which the present disclosure can be applied.

[0016] FIG. 6 is a drawing for explaining an example of a frame structure used in a wireless LAN system to which the present disclosure can be applied.

[0017] FIG. 7 is a diagram illustrating examples of PPDUs defined in the IEEE 802.11 standard to which the present disclosure can be applied.

[0018] FIG. 8 is a drawing showing an exemplary format of a trigger frame to which the present disclosure can be applied.

[0019] FIG. 9 is a diagram illustrating an example of a trigger-based feedback information response to which the present disclosure may be applied.

[0020] FIG. 10 is a diagram illustrating an example of the operation of the first STA according to the present disclosure.

[0021] FIG. 11 is a diagram illustrating an example of the operation of a second STA according to the present disclosure.

[0022] FIG. 12 is a diagram showing an example of control information according to the present disclosure.

[0023] FIG. 13 is a diagram showing examples of configurations of common control / feature information according to the present disclosure.

[0024] Figure 14 illustrates additional examples of IDC information fields according to the present disclosure.

[0025] FIG. 15 is a diagram showing various examples of formats of transmission information (or control / feedback information) according to the present disclosure.

[0026] FIG. 16 is a diagram illustrating additional examples of formats of transmission information (or control / feedback information) according to the present disclosure.

[0027] FIG. 17 is a diagram illustrating additional examples of formats of transmission information (or control / feedback information) according to the present disclosure.

[0028] FIG. 18 illustrates an example in which cross-link power saving information according to the present disclosure is included as feedback information.

[0029] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description set forth below, together with the accompanying drawings, is intended to explain exemplary embodiments of the present disclosure and is not intended to represent the only embodiments in which the present disclosure may be practiced. The following detailed description includes specific details to provide a thorough understanding of the present disclosure. However, one of ordinary skill in the art will appreciate that the present disclosure may be practiced without these specific details.

[0030] In some cases, to avoid obscuring the concepts of the present disclosure, known structures and devices may be omitted or illustrated in block diagram form focusing on the core functions of each structure and device.

[0031] In the present disclosure, when a component is said to be "connected," "coupled," or "connected" to another component, this may include not only a direct connection but also an indirect connection in which another component exists between them. Furthermore, the terms "comprises" or "has" in the present disclosure specify the presence of the mentioned 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.

[0032] In this disclosure, terms such as “first,” “second,” etc. are used only to distinguish one component from another and are not used to limit the components, and do not limit the order or importance between the components unless specifically stated otherwise. Accordingly, within the scope of this disclosure, a first component in one embodiment may be referred to as a second component in another embodiment, and similarly, a second component in one embodiment may be referred to as a first component in another embodiment.

[0033] The terminology used herein is for the purpose of describing particular embodiments and is not intended to limit the scope of the claims. As used in the description of the embodiments and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. The term "and / or" as used herein may refer to any one of the associated enumerated items, or is meant to refer to and encompass any and all possible combinations of two or more of them. Furthermore, the use of " / " between words in this disclosure has the same meaning as "and / or" unless otherwise stated.

[0034] The examples of the present disclosure can be applied to various wireless communication systems. For example, the examples of the present disclosure can be applied to a wireless LAN system. For example, the examples of the present disclosure can be applied to a wireless LAN based on the IEEE 802.11a / g / n / ac / ax / be standards. Furthermore, the examples of the present disclosure can be applied to a wireless LAN based on the newly proposed IEEE 802.11bn (or UHR) standard. Additionally, the examples of the present disclosure can be applied to a wireless LAN based on the next-generation standard after IEEE 802.11bn. Furthermore, the examples of the present disclosure can be applied to a cellular wireless communication system. For example, the examples of the present disclosure can be applied to a cellular wireless communication system based on the LTE (Long Term Evolution) series of technologies and the 5G NR (New Radio) series of technologies of the 3rd Generation Partnership Project (3GPP) standard.

[0035] Below, technical features to which examples of the present disclosure can be applied are described.

[0036] FIG. 1 illustrates a block diagram of a wireless communication device according to one embodiment of the present disclosure.

[0037] The first device (100) and the second device (200) illustrated in FIG. 1 may be replaced with 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. In addition, the first device (100) and the second device (200) may be replaced with 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.

[0038] The devices (100, 200) illustrated in FIG. 1 may also be referred to as stations (STAs). For example, the devices (100, 200) illustrated in FIG. 1 may be referred to by various terms such as transmitting device, receiving device, transmitting STA, and receiving STA. For example, the STAs (110, 200) may perform an AP (access point) role or a non-AP role. That is, in the present disclosure, the STAs (110, 200) may perform the functions of an AP and / or a non-AP. When the STAs (110, 200) perform an AP function, they may simply be referred to as APs, and when the STAs (110, 200) perform a non-AP function, they may simply be referred to as STAs. In addition, in the present disclosure, the APs may also be referred to as AP STAs.

[0039] Referring to FIG. 1, the first device (100) and the second device (200) can transmit and receive wireless signals through various wireless LAN technologies (e.g., IEEE 802.11 series). The first device (100) and the second device (200) can include interfaces for a medium access control (MAC) layer and a physical layer (PHY) that follow the provisions of the IEEE 802.11 standard.

[0040] In addition, the first device (100) and the second device (200) may additionally support various communication standards (e.g., 3GPP LTE series, 5G NR series standards, etc.) other than wireless LAN technology. In addition, the device of the present disclosure may be implemented as various devices such as a mobile phone, a vehicle, a personal computer, an AR (Augmented Reality) device, a VR (Virtual Reality) device, etc. In addition, the STA of the present specification may support various communication services such as voice calls, video calls, data communications, autonomous driving, MTC (Machine-Type Communication), M2M (Machine-to-Machine), D2D (Device-to-Device), and IoT (Internet-of-Things).

[0041] A 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 memories (104) and / or the transceivers (106), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. For example, the processor (102) may process information in the memories (104) to generate first information / signals, and then transmit a wireless signal including the first information / signals via the transceivers (106). Furthermore, the processor (102) may receive a wireless signal including second information / signals via the transceivers (106), and then store information obtained from signal processing of the second information / signals in the memory (104). The memory (104) may be connected to the processor (102) and may store various information related to the operation of the processor (102). For example, the memory (104) may perform some or all of the processes controlled by the processor (102), or may store software code including instructions for performing the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in the present disclosure. Here, the processor (102) and the memory (104) may be part of a communication modem / circuit / chip designed to implement a wireless LAN technology (e.g., IEEE 802.11 series). The transceiver (106) may be connected to the processor (102) and may transmit and / or receive wireless signals via one or more antennas (108). The transceiver (106) may include a transmitter and / or a receiver. The transceiver (106) may be used interchangeably with an RF (Radio Frequency) unit. In the present disclosure, a device may also mean a communication modem / circuit / chip.

[0042] The second device (200) includes one or more processors (202), one or more memories (204), and may further include one or more transceivers (206) and / or one or more antennas (208). The processor (202) controls the memories (204) and / or the transceivers (206), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. For example, the processor (202) may process information in the memory (204) to generate third information / signals, and then transmit a wireless signal including the third information / signals via the transceivers (206). Furthermore, the processor (202) may receive a wireless signal including fourth information / signals via the transceivers (206), and then store information obtained from signal processing of the fourth information / signals in the memory (204). The memory (204) may be connected to the processor (202) and may store various information related to the operation of the processor (202). For example, the memory (204) may perform some or all of the processes controlled by the processor (202), or may store software code including instructions for performing the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts 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 a wireless LAN technology (e.g., IEEE 802.11 series). The transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals via one or more antennas (208). The transceiver (206) may include a transmitter and / or a receiver. The transceiver (206) may be used interchangeably with an RF unit. In the present disclosure, a device may also mean a communication modem / circuit / chip.

[0043] Hereinafter, the hardware elements of the device (100, 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, 202). For example, one or more processors (102, 202) may implement one or more layers (e.g., functional layers such as PHY, MAC). One or more processors (102, 202) may generate one or more Protocol Data Units (PDUs) and / or one or more Service Data Units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. One or more processors (102, 202) may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. One or more processors (102, 202) can generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data or information according to the functions, procedures, proposals and / or methods disclosed in the present disclosure, and provide the signals to one or more transceivers (106, 206). One or more processors (102, 202) can receive signals (e.g., baseband signals) from one or more transceivers (106, 206) and obtain PDUs, SDUs, messages, control information, data or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed in the present disclosure.

[0044] One or more processors (102, 202) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. One or more processors (102, 202) may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Digital Signal Processing Devices (DSPDs), one or more Programmable Logic Devices (PLDs), or one or more Field Programmable Gate Arrays (FPGAs) may be included in one or more processors (102, 202). The descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this disclosure may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. The descriptions, functions, procedures, proposals, methods and / or operation flowcharts disclosed in this disclosure may be implemented using firmware or software configured to perform one or more processors (102, 202) or stored in one or more memories (104, 204) and driven by one or more processors (102, 202). The descriptions, functions, procedures, proposals, methods and / or operation flowcharts disclosed in this disclosure may be implemented using firmware or software in the form of codes, instructions and / or sets of instructions.

[0045] One or more memories (104, 204) may be coupled to one or more processors (102, 202) and may store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. The one or more memories (104, 204) may be configured as ROM, RAM, EPROM, flash memory, hard drives, registers, cache memory, computer-readable storage media, and / or combinations thereof. The one or more memories (104, 204) may be located internally and / or externally to the one or more processors (102, 202). Additionally, the one or more memories (104, 204) may be coupled to the one or more processors (102, 202) via various technologies, such as wired or wireless connections.

[0046] One or more transceivers (106, 206) can transmit user data, control information, wireless signals / channels, etc., as mentioned in the methods and / or flowcharts 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., as mentioned in the descriptions, functions, procedures, proposals, methods and / or flowcharts of the present disclosure, from one or more other devices. For example, one or more transceivers (106, 206) can be coupled to one or more processors (102, 202) and can transmit and receive wireless signals. For example, one or more processors (102, 202) can control one or more transceivers (106, 206) to transmit user data, control information, or wireless signals to one or more other devices. Additionally, one or more processors (102, 202) may control one or more transceivers (106, 206) to receive user data, control information, or wireless signals from one or more other devices. Additionally, one or more transceivers (106, 206) may be coupled 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, or the like, as referred to in the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts 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) can convert received user data, control information, 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 by one or more processors (102, 202) from baseband signals to RF band signals. For this purpose, one or more transceivers (106, 206) may include an (analog) oscillator and / or filter.

[0047] For example, one of the STAs (100, 200) may perform the intended operation of an AP, and the other of the STAs (100, 200) may perform the intended operation of a non-AP STA. For example, the transceivers (106, 206) of FIG. 1 may perform transmission and reception operations of signals (e.g., packets or PPDUs (Physical layer Protocol Data Units) according to IEEE 802.11a / b / g / n / ac / ax / be / bn, etc.). In addition, in the present disclosure, operations in which various STAs generate transmission and reception signals or perform data processing or calculations in advance for transmission and reception signals may be performed in the processors (102, 202) of FIG. 1. For example, an example of an operation for generating a transmission / reception signal or performing data processing or operation in advance for a transmission / reception signal may include 1) an operation for determining / obtaining / configuring / computing / decoding / encoding bit information of a field (SIG (signal), STF (short training field), LTF (long training field), Data, etc.) included in a PPDU, 2) an operation for determining / configuring / obtaining time resources or frequency resources (e.g., subcarrier resources) used for a field (SIG, STF, LTF, Data, etc.) included in a PPDU, 3) an operation for determining / configuring / obtaining a specific sequence (e.g., a pilot sequence, an STF / LTF sequence, an extra sequence applied to SIG) used for a field (SIG, STF, LTF, Data, etc.) included in a PPDU, 4) a power control operation and / or a power saving operation applied to an STA, 5) an operation related to determining / obtaining / configuring / computing / decoding / encoding an ACK signal, etc. Additionally, in the examples below, various information (e.g., information related to fields / subfields / control fields / parameters / power, etc.) used by various STAs for determining / acquiring / configuring / computing / decoding / encoding transmission / reception signals can be stored in the memory (104, 204) of FIG. 1.

[0048] Hereinafter, downlink (DL) refers to a link for communication from an AP STA to a non-AP STA, and downlink PPDUs / packets / signals, etc. can be transmitted and received through the downlink. In downlink communication, the transmitter may be part of an AP STA, and the receiver may be part of a non-AP STA. Uplink (UL) refers to a link for communication from a non-AP STA to an AP STA, and uplink PPDUs / packets / signals, etc. can be transmitted and received through the uplink. In uplink communication, the transmitter may be part of a non-AP STA, and the receiver may be part of an AP STA.

[0049] FIG. 2 is a diagram showing an exemplary structure of a wireless LAN system to which the present disclosure can be applied.

[0050] The structure of a wireless LAN system can be composed of multiple components. Through the interaction of multiple components, a wireless LAN that supports transparent STA mobility to the upper layer can be provided. A Basic Service Set (BSS) corresponds to a basic building block of a wireless LAN. FIG. 2 illustrates, by way of example, the existence of two BSSs (BSS1 and BSS2) and the inclusion of two STAs as members of each BSS (STA1 and STA2 are included in BSS1, and STA3 and STA4 are included in BSS2). The oval representing a BSS in FIG. 2 can also be understood as representing a coverage area in which STAs included in the corresponding BSS maintain communication. This area can be referred to as a Basic Service Area (BSA). When an STA moves outside of a BSA, it cannot directly communicate with other STAs within the BSA.

[0051] If we do not consider the DS illustrated in Figure 2, the most basic type of BSS in a wireless LAN is an Independent BSS (IBSS). For example, an IBSS can have a minimal form consisting of only two STAs. For example, assuming other components are omitted, BSS1 consisting of only STA1 and STA2, or BSS2 consisting of only STA3 and STA4, can be representative examples of an IBSS, respectively. Such a configuration is possible when the STAs can communicate directly without an AP. Furthermore, in this type of WLAN, a LAN can be configured when needed rather than being planned in advance, and this can be called an ad-hoc network. Since an IBSS does not include an AP, there is no centralized management entity. That is, in an IBSS, STAs are managed in a distributed manner. In IBSS, all STAs can be mobile STAs, and access to distributed systems (DS) is not permitted, forming a self-contained network.

[0052] An STA's membership in a BSS can dynamically change, for example, when an STA is turned on or off, or when an STA enters or leaves a BSS area. To become a member of a BSS, an STA can join the BSS using a synchronization process. To access all services in the BSS infrastructure, an STA must be associated with the BSS. This association can be dynamically established and may involve the use of a Distribution System Service (DSS).

[0053] In a wireless LAN, the direct STA-to-STA distance can be limited by PHY performance. While this distance limit may be sufficient in some cases, communication between STAs over longer distances may be required in other cases. To support extended coverage, a distributed system (DS) can be configured.

[0054] DS refers to a structure in which BSSs are interconnected. Specifically, a BSS may exist as an extended component of a network composed of multiple BSSs, as illustrated in Figure 2. DS is a logical concept and can be specified by the characteristics of a distributed system medium (DSM). In this regard, the Wireless Medium (WM) and DSM can be logically distinguished. Each logical medium is used for a different purpose and by different components. These media are neither limited to being identical nor limited to being different. This logical difference between multiple media explains the flexibility of the WLAN architecture (DS architecture or other network architectures). In other words, the WLAN architecture can be implemented in various ways, and the physical characteristics of each implementation can independently specify the WLAN architecture.

[0055] A DS can support mobile devices by providing seamless integration of multiple BSSs and the logical services necessary to handle addresses to destinations. Additionally, a DS may further include a component called a portal, which acts as a bridge for connecting wireless LANs to other networks (e.g., IEEE 802.X).

[0056] An AP is an entity that enables access to a DS through a WM for associated non-AP STAs and also has the functionality of an STA. Data movement between a BSS and a DS can be performed through an AP. For example, STA2 and STA3 illustrated in FIG. 2 have the functionality of an STA and provide the function of allowing associated non-AP STAs (STA1 and STA4) to access the DS. In addition, since all APs are basically STAs, all APs are addressable entities. The address used by an AP for communication on a WM and the address used by an AP for communication on a DSM do not necessarily have to be the same. A BSS consisting of an AP and one or more STAs can be referred to as an infrastructure BSS.

[0057] Data transmitted from one of the STA(s) associated with an AP to the STA address of that AP is always received on an uncontrolled port and can be processed by an IEEE 802.1X port access entity. In addition, if the controlled port is authenticated, the transmitted data (or frame) can be forwarded to the DS.

[0058] In addition to the structure of the DS described above, an extended service set (ESS) may be established to provide wider coverage.

[0059] An ESS is a network of arbitrary size and complexity, consisting of DSs and BSSs. An ESS may correspond to a set of BSSs connected to a DS. However, an ESS does not include a DS. An ESS network is characterized by appearing as an IBSS at the Logical Link Control (LLC) layer. STAs within an ESS can communicate with each other, and mobile STAs can move from one BSS to another (within the same ESS) transparently to the LLC. APs within an ESS may have the same SSID (service set identification). The SSID is distinct from the BSSID, which is the identifier of the BSS.

[0060] In a wireless LAN system, no assumptions are made about the relative physical locations of BSSs, and all of the following configurations are possible: BSSs can be partially overlapping, which is commonly used to provide continuous coverage. BSSs can also be physically disconnected, and there is no logical distance limit between them. BSSs can also be physically co-located, which can be used to provide redundancy. Furthermore, one (or more) IBSS or ESS networks can physically co-exist with one (or more) ESS networks. This can occur in cases where an ad-hoc network operates at the same location as an ESS network, where physically overlapping wireless networks are configured by different organizations, or where two or more different access and security policies are required at the same location.

[0061] FIG. 3 is a diagram for explaining a link setup process to which the present disclosure can be applied.

[0062] For an STA to set up a link and transmit and receive data on a network, it must first discover the network, perform authentication, establish an association, and complete security authentication procedures. The link setup process can also be referred to as the session initiation process or session setup process. Furthermore, the discovery, authentication, association, and security setup processes of the link setup process can be collectively referred to as the association process.

[0063] In step S310, the STA may perform a network discovery operation. This network discovery operation may include scanning operations by the STA. That is, for the STA to access a network, it must search for available networks. Before joining a wireless network, the STA must identify compatible networks. The process of identifying networks in a specific area is called scanning.

[0064] Scanning methods include active scanning and passive scanning. Figure 3 illustrates a network discovery operation including an active scanning process as an example. In active scanning, an STA performing scanning transmits a probe request frame to discover any APs in the vicinity while moving between channels and waits for a response. The responder transmits a probe response frame in response to the STA that transmitted the probe request frame. Here, the responder may be the STA that last transmitted a beacon frame in the BSS of the channel being scanned. In the BSS, the AP transmits the beacon frame, so the AP becomes the responder. In the IBSS, the STAs within the IBSS take turns transmitting beacon frames, so the responder is not fixed. For example, an STA that transmits a probe request frame on channel 1 and receives a probe response frame on channel 1 can store BSS-related information included in the received probe response frame and move to the next channel (e.g., channel 2) to perform scanning (i.e., transmitting and receiving probe requests / responses on channel 2) in the same manner.

[0065] Although not shown in Figure 3, the scanning operation can also be performed in a passive scanning manner. In passive scanning, the STA performing the scanning moves between channels and waits for a beacon frame. A beacon frame is one of the management frames defined in IEEE 802.11. It announces the existence of a wireless network and is periodically transmitted so that the STA performing the scanning can find the wireless network and participate in the wireless network. In the BSS, the AP performs the role of periodically transmitting the beacon frame, and in the IBSS, the STAs within the IBSS take turns transmitting the beacon frame. When the STA performing the scanning receives a beacon frame, it stores the information about the BSS included in the beacon frame and moves to another channel, recording the beacon frame information on each channel. The STA receiving the beacon frame stores the BSS-related information included in the received beacon frame and moves to the next channel to perform scanning on the next channel in the same manner. Comparing active scanning and passive scanning, active scanning has the advantage of lower delay and power consumption than passive scanning.

[0066] After the STA discovers the network, an authentication process may be performed in step S320. This authentication process may be referred to as the first authentication process to clearly distinguish it from the security setup operation of step S340 described below.

[0067] The authentication process involves the STA sending an authentication request frame to the AP, and the AP responding by sending an authentication response frame to the STA. The authentication frame used for the authentication request / response corresponds to a management frame.

[0068] The authentication frame may include information such as an authentication algorithm number, an authentication transaction sequence number, a status code, a challenge text, a Robust Security Network (RSN), and a Finite Cyclic Group. These are just some examples of information that may be included in an authentication request / response frame, and may be replaced with other information or include additional information.

[0069] An STA can send an authentication request frame to an AP. The AP can determine whether to grant authentication to the STA based on the information contained in the received authentication request frame. The AP can provide the result of the authentication process to the STA via an authentication response frame.

[0070] After the STA is successfully authenticated, an association process may be performed in step S330. The association process includes a process in which the STA transmits an association request frame to the AP, and in response, the AP transmits an association response frame to the STA.

[0071] For example, the association request frame may include information about various capabilities, a beacon listen interval, a service set identifier (SSID), supported rates, supported channels, RSN, a mobility domain, supported operating classes, a Traffic Indication Map Broadcast request, interworking service capabilities, etc. For example, the association response frame may include information about various capabilities, a status code, an Association ID (AID), supported rates, an Enhanced Distributed Channel Access (EDCA) parameter set, a Received Channel Power Indicator (RCPI), a Received Signal to Noise Indicator (RSNI), a mobility domain, a timeout interval (e.g., an association comeback time), overlapping BSS scan parameters, a TIM broadcast response, a Quality of Service (QoS) map, etc. These are just some examples of information that may be included in a combined request / response frame, and may be replaced by other information or include additional information.

[0072] After the STA successfully joins the network, a security setup process may be performed in step S340. The security setup process in step S340 may be referred to as an authentication process through a Robust Security Network Association (RSNA) request / response, the authentication process in step S320 may be referred to as a first authentication process, and the security setup process in step S340 may also be referred to simply as an authentication process.

[0073] The security setup process of step S340 may include, for example, a process of establishing a private key through a four-way handshaking using an Extensible Authentication Protocol over LAN (EAPOL) frame. Furthermore, the security setup process may be performed according to a security method not defined in the IEEE 802.11 standard.

[0074] FIG. 4 is a diagram for explaining a backoff process to which the present disclosure can be applied.

[0075] In wireless LAN systems, the basic access mechanism of MAC (Medium Access Control) is Carrier Sense Multiple Access with Collision Avoidance (CSMA / CA). The CSMA / CA mechanism, also known as the Distributed Coordination Function (DCF) of the IEEE 802.11 MAC, essentially employs a "listen before talk" access mechanism. According to this type of access mechanism, the AP and / or STA may perform a Clear Channel Assessment (CCA) to sense the wireless channel or medium for a predetermined time period (e.g., a DCF Inter-Frame Space (DIFS)) before starting transmission. If the sensing result determines that the medium is in an idle state, the AP and / or STA may start transmitting frames through the medium. On the other hand, if the medium is detected to be occupied or busy, the AP and / or STA may not start its own transmission, but may wait for a delay period (e.g., a random backoff period) for medium access before attempting to transmit frames. By applying a random backoff period, multiple STAs are expected to attempt to transmit frames after waiting for different periods of time, thereby minimizing collisions.

[0076] In addition, the IEEE 802.11 MAC protocol provides the Hybrid Coordination Function (HCF). The HCF is based on the DCF and the Point Coordination Function (PCF). The PCF is a polling-based synchronous access method that periodically polls all receiving APs and / or STAs to ensure that they receive data frames. In addition, the HCF has the Enhanced Distributed Channel Access (EDCA) and the HCF Controlled Channel Access (HCCA). The EDCA is a contention-based access method for a provider to provide data frames to multiple users, while the HCCA uses a non-contention-based channel access method that utilizes a polling mechanism. In addition, the HCF includes a medium access mechanism to improve the Quality of Service (QoS) of the wireless LAN, and can transmit QoS data in both the Contention Period (CP) and the Contention Free Period (CFP).

[0077] Referring to Fig. 4, an operation based on a random backoff period is described. When a medium that was occupied / busy changes to an idle state, multiple STAs can attempt to transmit data (or frames). To minimize collisions, each STA can select a random backoff count, wait for the corresponding slot time, and then attempt transmission. The random backoff count has a pseudo-random integer value and can be determined as one of the values ​​in the range of 0 to CW. Here, CW is a contention window parameter value. The CW parameter is given an initial value of CWmin, but can take a value doubled in case of transmission failure (e.g., when an ACK for a transmitted frame is not received). When the CW parameter value becomes CWmax, data transmission can be attempted while maintaining the CWmax value until data transmission is successful, and if data transmission is successful, it is reset to the CWmin value. The CW, CWmin, and CWmax values ​​are 2. n It is desirable to set it to -1 (n=0, 1, 2, ...).

[0078] Once the random backoff process begins, the STA continues to monitor the medium while counting down the backoff slots according to the determined backoff count value. If the medium is monitored as occupied, the countdown stops and waits. When the medium becomes idle, the remaining countdown resumes.

[0079] In the example of FIG. 4, when a packet to be transmitted reaches the MAC of STA3, STA3 can immediately transmit a frame if it confirms that the medium is idle for DIFS. The remaining STAs monitor the medium for occupied / busy states and wait. In the meantime, data to be transmitted may also occur in each of STA1, STA2, and STA5, and each STA can count down the backoff slot according to a random backoff count value selected by each STA after waiting for DIFS if the medium is monitored as idle. Assume that STA2 selects the smallest backoff count value and STA1 selects the largest backoff count value. In other words, this example shows a case 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 briefly stop counting down and wait while STA2 occupies the medium. When STA2's occupation ends and the medium becomes idle again, STA1 and STA5 wait for DIFS and then resume the backoff count that they had stopped. That is, they can start transmitting frames after counting down the remaining backoff slots equal to the remaining backoff time. Since STA5's remaining backoff time is shorter than STA1's, STA5 starts transmitting frames. While STA2 occupies the medium, STA4 may also have data to transmit. From STA4's perspective, when the medium becomes idle, it waits for DIFS, counts down according to its selected random backoff count value, and then starts transmitting frames. In the example of Figure 4, the remaining backoff time of STA5 coincidentally matches the random backoff count value of STA4, in which case a collision may occur between STA4 and STA5. If a collision occurs, neither STA4 nor STA5 will receive an ACK, resulting in a failure in data transmission.In this case, STA4 and STA5 can select a random backoff count value and perform a countdown after doubling the CW value. STA1 waits while the medium is occupied by transmissions from STA4 and STA5, and when the medium becomes idle, it waits for DIFS and can start transmitting frames after the remaining backoff time elapses.

[0080] As in the example of Fig. 4, a data frame is a frame used for transmitting data forwarded to a higher layer, and can be transmitted after a backoff performed after DIFS elapses from when the medium becomes idle. Additionally, 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 performed after an IFS elapses, such as DIFS or PIFS (Point coordination function IFS). Subtype frames of a management frame include a beacon, an association request / response, a re-association request / response, a probe request / response, and an authentication request / response. A control frame is a frame used to control access to the medium. The subtype frames of the control frame include Request-To-Send (RTS), Clear-To-Send (CTS), Acknowledgment (ACK), Power Save-Poll (PS-Poll), Block ACK (BlockAck), Block ACK Request (BlockACKReq), Null Data Packet Announcement (NDP), and Trigger. If the control frame is not a response frame to the previous frame, it is transmitted after a backoff performed after the DIFS (Direct Inverse Frame Stop) has elapsed, and if it is a response frame to the previous frame, it is transmitted without a backoff performed after the SIFS (short IFS). The type and subtype of the frame can be identified by the type field and subtype field in the Frame Control (FC) field.

[0081] A QoS (Quality of Service) STA can transmit a frame after a backoff performed after the 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), has elapsed. Here, the frames for which AIFS[i] can be used can be data frames, management frames, and also control frames that are not response frames.

[0082] FIG. 5 is a diagram for explaining a CSMA / CA-based frame transmission operation to which the present disclosure can be applied.

[0083] As mentioned above, the CSMA / CA mechanism includes virtual carrier sensing in addition to physical carrier sensing, in which STAs directly sense the medium. Virtual carrier sensing is intended to address potential issues in medium access, such as the hidden node problem. For virtual carrier sensing, the MAC of an STA can utilize a Network Allocation Vector (NAV). The NAV is a value that an STA that is currently using or has the right to use the medium indicates to other STAs the remaining time until the medium becomes available. Therefore, the value set as NAV corresponds to the period during which the STA transmitting the frame is scheduled to use the medium, and an STA receiving the NAV value is prohibited from accessing the medium during that period. For example, the NAV can be set based on the value of the "duration" field in the MAC header of the frame.

[0084] In the example of FIG. 5, it is assumed that STA1 wants to transmit data to STA2, and STA3 is in a position to overhear some or all of the frames transmitted and received between STA1 and STA2.

[0085] In order to reduce the possibility of collisions in transmissions of multiple STAs in a CSMA / CA-based frame transmission operation, a mechanism using RTS / CTS frames may be applied. In the example of FIG. 5, while STA1 is transmitting, STA3 may determine that the medium is idle based on carrier sensing results. That is, STA1 may correspond to a hidden node for STA3. Alternatively, in the example of FIG. 5, while STA2 is transmitting, STA3 may determine that the medium is idle based on carrier sensing results. That is, STA2 may correspond to a hidden node for STA3. By exchanging RTS / CTS frames before performing data transmission and reception between STA1 and STA2, STAs outside the transmission range of either STA1 or STA2, or STAs outside the carrier sensing range for transmissions from STA1 or STA3, may not attempt to occupy the channel during data transmission and reception between STA1 and STA2.

[0086] Specifically, STA1 can determine whether a channel is occupied through carrier sensing. In terms of physical carrier sensing, STA1 can determine channel occupancy idleness based on the energy level or signal correlation detected in the channel. Furthermore, in terms of virtual carrier sensing, STA1 can determine the channel occupancy status using a network allocation vector (NAV) timer.

[0087] STA1 can transmit an RTS frame to STA2 after performing a backoff if the channel is idle during the DIFS. STA2 can transmit a CTS frame, which is a response to the RTS frame, to STA1 after an SIFS if it receives the RTS frame.

[0088] If STA3 cannot overhear a CTS frame from STA2 but can overhear an RTS frame from STA1, STA3 can use the duration information contained in the RTS frame to set a NAV timer for the subsequent consecutively transmitted frame transmission period (e.g., SIFS + CTS frame + SIFS + data frame + SIFS + ACK frame). Alternatively, if STA3 cannot overhear an RTS frame from STA1 but can overhear a CTS frame from STA2, STA3 can use the duration information contained in the CTS frame to set a NAV timer for the subsequent consecutively transmitted frame transmission period (e.g., SIFS + data frame + SIFS + ACK frame). That is, if STA3 can overhear one or more of the RTS or CTS frames from one or more of STA1 or STA2, it can set a NAV accordingly. If STA3 receives a new frame before the NAV timer expires, it can update the NAV timer using the duration information contained in the new frame. STA3 does not attempt channel access until the NAV timer expires.

[0089] If STA1 receives a CTS frame from STA2, it can transmit a data frame to STA2 after SIFS from the time when the CTS frame is completely received. If STA2 successfully receives the data frame, it can transmit an ACK frame in response to the data frame to STA1 after SIFS. STA3 can determine whether the channel is in use through carrier sensing if the NAV timer expires. If STA3 determines that the channel is not in use by another terminal during the DIFS after the NAV timer expires, it can attempt channel access after a contention window (CW) based on a random backoff has elapsed.

[0090] FIG. 6 is a drawing for explaining an example of a frame structure used in a wireless LAN system to which the present disclosure can be applied.

[0091] The PHY layer can prepare an MPDU (MAC PDU) to be transmitted based on an instruction or primitive (meaning a set of instructions or parameters) from the MAC layer. For example, when a command requesting the start of transmission of the PHY layer is received from the MAC layer, the PHY layer can switch to transmission mode and transmit the information (e.g., data) provided by the MAC layer in the form of a frame. In addition, when the PHY layer detects a valid preamble of the received frame, it monitors the header of the preamble and sends a command to the MAC layer notifying the start of reception of the PHY layer.

[0092] In this way, information transmission / reception in a wireless LAN system is done in the form of frames, and for this purpose, the PHY layer Protocol Data Unit (PPDU) format is defined.

[0093] A basic PPDU may include a Short Training Field (STF), a Long Training Field (LTF), a SIGNAL (SIG) field, and a Data field. The most basic (e.g., non-HT (High Throughput) as illustrated in FIG. 7) PPDU format may consist of only the Legacy-STF (L-STF), Legacy-LTF (L-LTF), Legacy-SIG (L-SIG) fields, and a Data field. Additionally, depending on the type of PPDU format (e.g., HT-mixed format PPDU, HT-greenfield format PPDU, VHT (Very High Throughput) PPDU, etc.), additional (or different types of) RL-SIG, U-SIG, non-legacy SIG field, non-legacy STF, non-legacy LTF, (i.e., xx-SIG, xx-STF, xx-LTF (e.g., xx is HT, VHT, HE, EHT, etc.)) may be included between the L-SIG field and the data field. More specific details are described below with reference to FIG. 7.

[0094] STF is a signal for signal detection, AGC (Automatic Gain Control), diversity selection, and precise time synchronization, while LTF is a signal for channel estimation, frequency error estimation, etc. STF and LTF can be said to be signals for synchronization and channel estimation of the OFDM physical layer.

[0095] The SIG field may include various information related to PPDU transmission and reception. For example, the L-SIG field may consist of 24 bits and may include a 4-bit Rate field, a 1-bit Reserved bit, a 12-bit Length field, a 1-bit Parity field, and a 6-bit Tail field. The RATE field may include information about the modulation and coding rate of data. For example, the 12-bit Length field may include information about the length or time duration of the PPDU. For example, the value of the 12-bit Length field may be determined based on the type of the PPDU. For example, for a non-HT, HT, VHT, or EHT PPDU, the value of the Length field may be determined as a multiple of 3. For example, for HE PPDU, the value of the Length field can be determined as a multiple of 3 + 1 or a multiple of 3 + 2.

[0096] The data field may include a SERVICE field, a Physical layer Service Data Unit (PSDU), a PPDU TAIL bit, and, if necessary, padding bits. Some bits of the SERVICE field may be used to synchronize the descrambler at the receiving end. The PSDU corresponds to a MAC PDU defined at the MAC layer and may contain data generated / used by upper layers. The PPDU TAIL bit may be used to return the encoder to a 0 state. The padding bit may be used to adjust the length of the data field to a predetermined unit.

[0097] MAC PDUs are defined according to various MAC frame formats, and a basic MAC frame consists of a MAC header, a frame body, and a Frame Check Sequence (FCS). A MAC frame is composed of MAC PDUs and can be transmitted / received through the PSDU in the data portion of the PPDU format.

[0098] The MAC header includes a Frame Control field, a Duration / ID field, an Address field, etc. The Frame Control field may include control information required for frame transmission / reception. The Duration / ID field may be set to a time for transmitting the corresponding frame, etc. The Address subfields may indicate the receiver address, transmitter address, destination address, and source address of the frame, and some Address subfields may be omitted. For specific details of each subfield of the MAC header, including the Sequence Control, QoS Control, and HT Control subfields, refer to the IEEE 802.11 standard document.

[0099] The Null-Data PPDU (NDP) format refers to a PPDU format that does not include a data field. In other words, NDP refers to a frame format that includes a PPDU preamble (i.e., L-STF, L-LTF, L-SIG fields, and, if additionally present, non-legacy SIG, non-legacy STF, and non-legacy LTF) in the general PPDU format, and does not include the remaining part (i.e., data field).

[0100] FIG. 7 is a diagram illustrating examples of PPDUs defined in the IEEE 802.11 standard to which the present disclosure can be applied.

[0101] Standards such as IEEE 802.11a / g / n / ac / ax use various PPDU formats. 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)).

[0102] The HT PPDU format (IEEE 802.11n) additionally includes HT-SIG, HT-STF, and HT-LFT(s) fields in addition to the basic PPDU format. The HT PPDU format illustrated in Fig. 7(b) may be referred to as an HT-mixed format. Additionally, an HT-greenfield format PPDU may be defined, which corresponds to a format that does not include L-STF, L-LTF, and L-SIG, but consists of HT-GF-STF, HT-LTF1, HT-SIG, one or more HT-LTF, and Data fields (not illustrated).

[0103] An example of the VHT PPDU format (IEEE 802.11ac) includes VHT SIG-A, VHT-STF, VHT-LTF, and VHT-SIG-B fields in addition to the basic PPDU format (Fig. 7(c)).

[0104] An example of a HE PPDU format (IEEE 802.11ax) additionally includes RL-SIG (Repeated L-SIG), HE-SIG-A, HE-SIG-B, HE-STF, HE-LTF(s), and PE (Packet Extension) fields in addition to the basic PPDU format (Fig. 7(d)). Depending on specific examples of the HE PPDU format, some fields may be excluded or their lengths may vary. For example, the HE-SIG-B field is included in the HE PPDU format for multi-users (MUs), but the HE-SIG-B is not included in the HE PPDU format for single users (SUs). In addition, the HE trigger-based (TB) PPDU format does not include the HE-SIG-B, and the length of the HE-STF field may vary to 8 microseconds (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 can vary to 16us. For example, the RL-SIG can be configured identically to the L-SIG. The receiving STA can determine that the received PPDU is a HE PPDU or an EHT PPDU, described later, based on the presence of the RL-SIG.

[0105] The EHT PPDU format may include the EHT MU (multi-user) PPDU 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 an L-SIG, but may include a U (universal)-SIG, an EHT-SIG, an EHT-STF, and an EHT-LTF following the RL-SIG.

[0106] The EHT MU PPDU in 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 can be used for both SU transmission and MU transmission. For example, the EHT MU PPDU can correspond to a PPDU for one receiving STA or multiple receiving STAs.

[0107] The EHT TB PPDU of Fig. 7(f) omits the EHT-SIG compared to the EHT MU PPDU. An STA that has received 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.

[0108] The L-STF, L-LTF, L-SIG, RL-SIG, U-SIG (Universal SIGNAL), and EHT-SIG fields can be encoded and modulated to allow legacy STAs to attempt demodulation and decoding, and mapped based on a predetermined subcarrier frequency interval (e.g., 312.5 kHz). These can be referred to as pre-EHT modulated fields. Next, the EHT-STF, EHT-LTF, Data, and PE fields can be encoded and modulated to allow STAs that have successfully decoded non-legacy SIGs (e.g., U-SIG and / or EHT-SIG) and obtained the information contained in the fields, and mapped based on a predetermined subcarrier frequency interval (e.g., 78.125 kHz). These can be referred to as EHT modulated fields.

[0109] Similarly, in the HE PPDU format, the L-STF, L-LTF, L-SIG, RL-SIG, HE-SIG-A, and HE-SIG-B fields may be referred to as pre-HE modulation fields, and the HE-STF, HE-LTF, Data, and PE fields may be referred to as HE modulation fields. Additionally, in the VHT PPDU format, the L-STF, L-LTF, L-SIG, and VHT-SIG-A fields may be referred to as pre-VHT modulation fields, and the VHT STF, VHT-LTF, VHT-SIG-B, and Data fields may be referred to as VHT modulation fields.

[0110] The U-SIG included in the EHT PPDU format of FIG. 7 can be configured based on, for example, two symbols (e.g., two consecutive OFDM symbols). Each symbol (e.g., OFDM symbol) for the U-SIG can have a duration of 4 us, and the U-SIG can have a total duration of 8 us. Each symbol of the U-SIG can be used to transmit 26 bits of information. For example, each symbol of the U-SIG can be transmitted and received based on 52 data tones and 4 pilot tones.

[0111] U-SIGs can be configured in 20MHz units. For example, when an 80MHz PPDU is configured, the same U-SIG can be duplicated in 20MHz units. That is, four identical U-SIGs can be included in an 80MHz PPDU. When the bandwidth exceeds 80MHz, for example, for a 160MHz PPDU, the U-SIGs in the first 80MHz unit and the U-SIGs in the second 80MHz unit can be different.

[0112] For example, A uncoded bits may be transmitted via U-SIG, and a first symbol of U-SIG (e.g., a U-SIG-1 symbol) may transmit the first X bits of information out of a total A bits of information, and a second symbol of U-SIG (e.g., a U-SIG-2 symbol) may transmit the remaining Y bits of information out of a total A bits of information. The A bits of information (e.g., 52 uncoded bits) may include a CRC field (e.g., a field of 4 bits in length) and a tail field (e.g., a field of 6 bits in length). The tail field may be used to terminate the trellis of the convolutional decoder and may be set to 0, for example.

[0113] The A bit information transmitted by U-SIG can be divided into version-independent bits and version-dependent bits. For example, U-SIG can be included in a new PPDU format (e.g., UHR PPDU format) not shown in FIG. 7, and in the format of the U-SIG field included in the EHT PPDU format and the format of the U-SIG field included in the UHR PPDU format, the version-independent bits can be the same, and some or all of the version-dependent bits can be different.

[0114] For example, the size of the version-independent bits of U-SIG can be fixed or variable. The version-independent bits can be assigned only to U-SIG-1 symbols, or to both U-SIG-1 symbols and U-SIG-2 symbols. The version-independent bits and the version-dependent bits can be called by various names, such as the first control bit and the second control bit.

[0115] For example, the version-independent bits of the U-SIG may include a 3-bit PHY version identifier, which may indicate the PHY version (e.g., EHT, UHR, etc.) of the transmitted and received PPDUs. The version-independent bits of the U-SIG may include a 1-bit UL / DL flag field. The first value of the 1-bit UL / DL flag field relates to UL communication, and the second value of the UL / DL flag field relates to DL communication. The version-independent bits of the U-SIG may include information about the length of a transmission opportunity (TXOP) and information about a BSS color ID.

[0116] For example, the version-dependent bits of the U-SIG may contain information that directly or indirectly indicates the type of PPDU (e.g., SU PPDU, MU PPDU, TB PPDU, etc.).

[0117] Information required for PPDU transmission and reception may be included in the U-SIG. For example, the U-SIG may further include information about bandwidth, information about the MCS technique applied to the non-legacy SIG (e.g., EHT-SIG or UHR-SIG), information indicating whether a dual carrier modulation (DCM) technique (e.g., a technique to achieve an effect similar to frequency diversity by reusing the same signal on two subcarriers) is applied to the non-legacy SIG, information about the number of symbols used for the non-legacy SIG, information about whether the non-legacy SIG is generated across the entire band, etc.

[0118] Some of the information required for transmitting and receiving a PPDU may be included in the U-SIG and / or the non-legacy SIG (e.g., EHT-SIG or UHR-SIG, etc.). For example, information about the type of the non-legacy LTF / STF (e.g., EHT-LTF / EHT-STF or UHR-LTF / UHR-STF, etc.), information about the length of the non-legacy LTF and the cyclic prefix (CP) length, information about the guard interval (GI) applicable to the non-legacy LTF, information about preamble puncturing applicable to the PPDU, information about resource unit (RU) 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.

[0119] Preamble puncturing may refer to the transmission of a PPDU in which no signal is present in one or more frequency units within the PPDU's 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 greater than a certain size.

[0120] 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 over at least one symbol, and each 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.).

[0121] Non-legacy SIGs, such as HE-SIG-B and EHT-SIG, may contain common fields and user-specific fields. Common and user-specific fields may be coded separately.

[0122] In some cases, common fields may be omitted. For example, in a compressed mode where non-OFDMA (orthogonal frequency multiple access) is applied, common fields may be omitted, and multiple STAs may receive PPDUs (e.g., data fields of PPDUs) over the same frequency band. In a non-compressed mode where OFDMA is applied, multiple users may receive PPDUs (e.g., data fields of PPDUs) over different frequency bands.

[0123] The number of user-specific fields can be determined based on the number of users. A single user block field can contain up to two user fields. Each user field can be associated with either MU-MIMO allocation or non-MU-MIMO allocation.

[0124] The common field may include CRC bits and Tail bits, the length of the CRC bits may be determined as 4 bits, and the length of the Tail bits may be determined as 6 bits and set to 000000. The common field may include RU allocation information. The RU allocation information may include information about the location of RUs to which multiple users (i.e., multiple receiving STAs) are allocated.

[0125] An RU can contain multiple subcarriers (or tones). RUs can be used when transmitting signals to multiple STAs based on OFDMA techniques. RUs can also be defined when transmitting signals to a single STA. Resources can be allocated on an RU basis for non-legacy STFs, non-legacy LTFs, and data fields.

[0126] Depending on the PPDU bandwidth, an applicable RU size can be defined. The RU may be defined identically or differently for the applicable PPDU format (e.g., HE PPDU, EHT PPDU, UHR PPDU, etc.). For example, in the case of an 80MHz PPDU, the RU arrangements of HE PPDU and EHT PPDU may be different. The applicable RU size, RU number, RU position, DC (direct current) subcarrier position and number, null subcarrier position and number, guard subcarrier position and number, etc. for each PPDU bandwidth can be referred to as a tone plan. For example, a tone plan for a wide bandwidth can be defined in the form of multiple repetitions of a low bandwidth tone plan.

[0127] RUs of different sizes can be defined, such as 26-ton RU, 52-ton RU, 106-ton RU, 242-ton RU, 484-ton RU, 996-ton RU, 2X996-ton RU, 4X996-ton RU, etc. A multiple RU (MRU) is distinguished from multiple individual RUs and corresponds to a group of subcarriers consisting of multiple RUs. For example, one MRU can be defined as 52+26-tons, 106+26-tons, 484+242-tons, 996+484-tons, 996+484+242-tons, 2X996+484-tons, 3X996-tons, or 3X996+484-tons. Additionally, multiple RUs constituting one MRU may or may not be consecutive in the frequency domain.

[0128] The specific size of an RU may be reduced or expanded. Therefore, the specific size of each RU (i.e., the number of corresponding tones) in the present disclosure is not limited and is exemplary. Furthermore, within a given bandwidth (e.g., 20, 40, 80, 160, 320 MHz, etc.) in the present disclosure, the number of RUs may vary depending on the RU size.

[0129] The names of each field in the PPDU formats of FIG. 7 are exemplary and the scope of the present disclosure is not limited by those names. Furthermore, the examples of the present disclosure can be applied not only to the PPDU format exemplified in FIG. 7, but also to a new PPDU format in which some fields are excluded and / or some fields are added based on the PPDU formats of FIG. 7.

[0130] FIG. 8 is a drawing showing an exemplary format of a trigger frame to which the present disclosure can be applied.

[0131] A trigger frame may allocate resources for the transmission of one or more TB PPDUs and request the transmission of TB PPDUs. The trigger frame may also include other information required by the STA transmitting the TB PPDU in response. The trigger frame may include common information and a user information list field in the frame body.

[0132] The common information field may include information that is common to one or more TB PPDU transmissions requested by a trigger frame, such as trigger type, UL length, presence of a subsequent trigger frame (e.g., More TF), whether CS (channel sensing) is required, UL BW (bandwidth), etc. Fig. 8 illustrates an example of an EHT variant common information field format.

[0133] The 4-bit trigger type subfield can 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 to correspond to basic, Beamforming Report Poll (BFRP), multi user-block acknowledgement request (MU-BAR), multi user-request to send (MU-RTS), Buffer Status Report Poll (BSRP), groupcast with retries (GCR) MU-BAR, Bandwidth Query Report Poll (BQRP), and NDP Feedback Report Poll (NFRP), respectively, and the values ​​8 to 15 are defined as reserved.

[0134] Among the common information, the trigger dependent common info subfield may include information that is optionally included based on the trigger type.

[0135] A special user info field may be included within the trigger frame. The special user info field does not contain user-specific information, but rather extended common information not provided in the common information field.

[0136] A user information list contains zero or more user information fields. Figure 8 illustrates an example of an EHT variant user information field format.

[0137] The AID12 subfield basically indicates that it is a user information field for an STA with the corresponding AID. In addition, if 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 information field. The special user information field is a user information field that does not contain user-specific information, but contains extended common information not provided in the common information field. For example, the special user information field can be identified by the AID12 value of 2007, and the special user information field flag subfield within the common information field can indicate whether the special user information field is included.

[0138] The RU allocation subfield can indicate the size and location of an RU / MRU. For this purpose, the RU allocation subfield can be interpreted together with the PS160 (primary / secondary 160MHz) subfield of the user information field, the UL BW subfield of the common information field, etc.

[0139] For example, the mapping of B7-B1 of the RU Allocation subfield can be defined together with the settings of the B0 and PS160 subfields of the RU Allocation subfield as shown in Table 1 below. Table 1 shows an example of encoding of the PS160 subfield and the RU Allocation subfield of the EHT Variant User Information Field.

[0140]

[0141]

[0142]

[0143] When B0 of the RU Allocation subfield is set to 0, it may indicate that the RU / MRU allocation is applied to the primary 80 MHz channel, and when its value is set to 1, it may indicate that the RU allocation is applied to the secondary 80 MHz channel of the primary 160 MHz. When B0 of the RU Allocation subfield is set to 0, it may indicate that the RU / MRU allocation is applied to the lower 80 MHz of the secondary 160 MHz, and when its value is set to 1, it may indicate that the RU allocation is applied to the upper 80 MHz of the secondary 160 MHz.

[0144] In the trigger frame RU allocation table of Table 1, the parameter N can be calculated based on the formula N=2*X1+X0. For a bandwidth of 80 MHz or less, the values ​​of PS160, B0, X0, and X1 can be set to 0. For a bandwidth of 160 MHz and a bandwidth of 320 MHz, the values ​​of PS160, B0, X0, and X1 can be set as shown in Table 2. These settings represent the absolute frequency order for the primary and secondary 80 MHz and 160 MHz channels. The order from left to right represents the order from low frequency to high frequency. The primary 80 MHz channel is represented as P80, the secondary 80 MHz channel is represented as S80, and the secondary 160 MHz channel is represented as S160.

[0145]

[0146] Providing feedback information through trigger frames

[0147] The existing trigger frame is defined for the purpose of soliciting a TB PPDU response for multi-user (MU) transmissions from one or more STAs. For example, the basic trigger frame can be used as a solicitation to receive data from peer STA(s) via UL MU transmissions. The multi-user block ack request (MU-BAR) trigger frame can be used as a solicitation to receive a block ACK (BA) from peer STA(s) via UL MU transmissions.

[0148] Meanwhile, various features such as in-device coexistence (IDC), dynamic power saving (DPS), multi-AP (MAP), non-primary channel access (NPCA), and security enhancement are being considered to expand the functionality of wireless LAN systems. To support these features, initial control frames (ICF), initial control response (ICR), and control response frames (CRF) may be defined. To implement these features, it may be necessary to define extensions / modifications of existing trigger and response frames and new frame exchange processes.

[0149] FIG. 9 is a diagram illustrating an example of a trigger-based feedback information response to which the present disclosure may be applied.

[0150] The AP may transmit a buffer status report poll (BSRP) trigger frame (TF) to STA1, STA2, and STA3 to request a buffer status report (BSR) from the STAs. The trigger frame may include information about the RU allocated to each STA, and each STA may transmit a TB PPDU in the RU allocated to it.

[0151] Here, information requesting additional control information (e.g., IDC-related information) from the STA may be included in the BSRP TF. Accordingly, each STA supporting IDC may send the AP a response frame containing additional IDC-related information in addition to the BSR.

[0152] For example, STA2 and STA3 provide BSR and IDC-related information to the AP, and STA1, which does not support IDC, can transmit BSR to the AP. STA3 may be an STA that supports enhanced multi-link single-radio operation.

[0153] Considering the feedback information from these STAs, the AP can transmit a basic trigger frame or data frame to STA1. If it is a basic trigger frame, STA1 can respond by transmitting a TB PPDU to the AP (not shown). During this process, STA2 and STA3 can perform IDC operations.

[0154] As mentioned above, in order to support various functions such as IDC, DPS, MAP, NPCA, and security enhancement through extensions such as ICF, ICR, and CRF, it is necessary to define various frame exchange procedures and the formats of trigger frames and response frames in the procedures. For example, it is possible to consider specifying a trigger-based response frame through extension / modification of the trigger frame, including information to be conveyed to the peer STA in the trigger frame, or defining a response frame that includes additional information solicited by the trigger frame.

[0155] In various examples of the present disclosure described below, the entity transmitting the trigger frame (e.g., the first STA) may be either an AP or a non-AP STA. In addition, the entity transmitting the response frame (e.g., the second STA) may be either an AP or a non-AP STA. In addition, the exchange of the trigger frame and the response frame between the first STA and the second STA may be performed in an AP-to-AP, non-AP STA-to-AP, AP-to-non-AP STA, or non-AP STA-to-non-AP STA relationship.

[0156] FIG. 10 is a diagram illustrating an example of the operation of the first STA according to the present disclosure.

[0157] In step S1010, the first STA may generate a trigger frame including one or more first user information fields including feedback information.

[0158] In some examples, the first user information field may include a feedback type field and a feedback information field. Additionally, the first user information field may further include an AID12 field. For example, the first user information field may include an AID12 field, a feedback type field, and a feedback information field in that order.

[0159] In some examples, when a trigger frame includes multiple first user information fields, the value of the AID12 field of one of the first user information fields may be set to the same specific value as the value of the AID12 field of another second user information field. The values ​​of the AID12 fields of the multiple first user information fields may all be set to the same specific value. For example, the same specific value may be 2008.

[0160] In some examples, when the feedback type field of any one of the first user information fields is set to a first value (e.g., 0), the feedback information field of the first user information field may include unavailability-related information. For example, the unavailability-related information may include start time information and / or duration information.

[0161] In some examples, when the feedback type field of another first user information field is set to a second value (e.g., 1), the feedback information field of that first user information field may include other control / feature / feedback information (e.g., information related to one of low latency (LL), dynamic power saving (DPS), multi-access point (MAP), non-primary channel access (NPCA), or security enhancement).

[0162] In some examples, the feedback information contained in one or more of the first user information fields may not be user-specific information. Alternatively, the feedback information contained in one or more of the first user information fields may be common information.

[0163] In some examples, the trigger frame may further include one or more second user information fields. For example, the AID12 field of such second user information fields may be set to a value corresponding to the identification information of another STA (e.g., an AP STA or a non-AP STA receiving the trigger frame). The feedback information field included in the second user information field, which includes the AID12 field set to the identification information of a specific STA, may include feedback information specific to the specific STA.

[0164] In some examples, the trigger frame may correspond to a buffer status report poll (BSRP) trigger frame. For example, the values ​​of the fields for the guard interval (GI) and long training field (LTF) type of the BSRP trigger frame may be set to 3.

[0165] In step S1020, the first STA may transmit a PPDU including a trigger frame to the second STA.

[0166] In some examples, a multi-STA block ACK (acknowledgement) frame may be transmitted from a second STA in response to a BSRP trigger frame, and may be received by the first STA. For example, if the trigger frame is an individually addressed BSRP trigger frame, and the values ​​of the fields for GI and LTF types in such BSRP trigger frame are set to 3, the PPDU transmitted in response to the BSRP trigger frame may be a non-high throughput (HT) PPDU or a non-HT duplicate PPDU including the multi-STA block ACK frame.

[0167] The method 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 generate a trigger frame including one or more first user information fields including feedback information, and transmit a PPDU including the trigger frame to a second STA via one or more transceivers (106). Furthermore, one or more memories (104) of the first device (100) may store commands for performing the method described in the example of FIG. 10 or the examples described below when executed by one or more processors (102).

[0168] For example, the memory (104) may store various information related to feedback information included in a trigger frame according to the present disclosure. The processor (102) may generate a frame with information / fields related to the feedback information included in the trigger frame based on the information stored in the memory (104), generate various RUs, generate a PPDU, and transmit the generated PPDU through the transceiver (106). In addition, the processor (102) may generate a transmission PPDU and store information about the transmission PPDU in the memory (104). For example, the processor (102) may be configured to perform an operation of the first STA according to an example of the present disclosure. For example, the processor (102) may be configured to determine information / fields related to feedback information included in the trigger frame, generate a frame / PPDU including the information / field, and transmit the frame / PPDU through the transceiver (106).

[0169] FIG. 11 is a drawing for explaining an example of the operation of a second STA according to the present disclosure.

[0170] In step S1110, the second STA may receive a trigger frame including one or more first user information fields including feedback information from the first STA.

[0171] In step S1120, the second STA may transmit a response frame in response to the trigger frame to the first STA.

[0172] In the example of Fig. 11, the format of the fields included in the trigger frame, the feedback information included in the trigger frame (first user information field, second user information field, etc.), the response frame, etc. are the same as in the example of Fig. 10, so redundant descriptions are omitted.

[0173] The method 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 configured to receive a trigger frame including one or more first user information fields including feedback information from a first STA through one or more transceivers (206), and to transmit a response frame responding to the trigger frame to the first STA through one or more transceivers (206). Furthermore, one or more memories (204) of the second device (200) may store commands for performing the method described in the example of FIG. 11 or the examples described below when executed by one or more processors (202).

[0174] For example, the memory (204) can store various information related to feedback information included in the trigger frame according to the present disclosure. The transceiver (206) can receive a PPDU based on the control of the processor (202). The PPDU received through the transceiver (206) can be stored in the memory (204). For example, the processor (202) can obtain control information for bandwidth / tone-plan / RU included in the PPDU (e.g., information included in the SIG field of the PPDU) and store the obtained control information in the memory (204). The processor (202) can perform decoding on the received PPDU. For example, the processor can perform an operation of restoring the results of cyclic shift delay (CSD), spatial mapping, inverse discrete Fourier transform (IDFT) / inverse fast Fourier transform (IFFT) operation, and guard interval (GI) insertion applied to the PPDU. In addition, the processor (202) can decode the data field of the PPDU received through the transceiver (206) and process the decoded data. For example, the processor (202) can transmit information about the decoded data field to a higher layer (e.g., a MAC layer). In addition, if the generation of a signal is instructed from the higher layer to the PHY layer in response to the data transmitted to the higher layer, a subsequent operation can be performed. For example, the processor can parse the MAC PDU obtained through PHY decoding of the DATA field of the PPDU received through the transceiver (206). In addition, the processor (202) can be configured to obtain information related to a feedback response from a trigger frame included in the MAC PDU and perform an operation accordingly. For example, the processor (202) of the receiving device can be configured to perform the operation of the second STA according to an example of the present disclosure.For example, the processor (202) may be configured to receive a trigger frame including feedback information, decode / parse a frame addressed to it based thereon, and transmit a response frame to the trigger frame.

[0175] In the examples of FIGS. 10 and 11, the first STA may transmit one or more PPDUs / frames containing feedback information (or delivered information). For example, the feedback information may include control information related to MAP, DPS, NPCA, IDC, security enhancement, etc., and / or existing control information (e.g., BSR).

[0176] Additionally or alternatively, feedback / forwarding information may be included in the common information field of the trigger frame in a bitmap-directed and / or bit-indexed manner.

[0177] Additionally or alternatively, the feedback / forwarding information may be indicated by a forwarding information flag in the common information field of the trigger frame and may be included in a bitmap-directed and / or bit-indexed manner in the user information field of the trigger frame.

[0178] Additionally or alternatively, feedback / forwarding information may be indicated based on an ID within the trigger frame.

[0179] Additionally or alternatively, the per user information in the trigger frame may include per user information related to MAP, DPS, NPCA, IDC, security enhancements, etc. and / or existing per user information (e.g., BSR).

[0180] Per-user information may be included in the user information field of the trigger frame by utilizing the reserved bit (B25) of the additional user information field for a specific STA - the user information field.

[0181] Additionally or alternatively, per-user information may be placed separately from the existing user information fields and in a different location (e.g., after the common control information field).

[0182] In the examples of FIGS. 10 and 11, the second STA may determine the operation and capabilities of the first STA for a new feature related to the feedback / transmission information included in the trigger frame. For example, the second STA may determine whether the first STA transmits in the IDC section and its capabilities through frame detection.

[0183] A second STA that detects a trigger frame including feedback / forwarding information of a first STA can transmit a frame responding to the trigger frame.

[0184] The examples of FIGS. 10 and 11 may correspond to some of the various examples of the present disclosure. Below, various examples of the present disclosure, including the examples of FIGS. 10 and 11, will be described in more detail.

[0185] The following examples illustrate a method for including feedback information (or forwarding information) in a trigger frame (e.g., a BSRP trigger frame). The BSRP trigger frame is merely exemplary, and the examples of the present disclosure may also be applied to trigger frames in other formats (or an ICF used at the start of a TXOP, or a control request frame used at a point after the start of a TXOP).

[0186] Example 1

[0187] This embodiment relates to control information (e.g., feedback information or transmission information) that may be included in a trigger frame. The control information may include, for example, MAP, DPS, IDC, NPCA, security enhancement, and / or existing A-control (e.g., BSR).

[0188] FIG. 12 is a diagram showing an example of control information according to the present disclosure.

[0189] Control information may be included in the trigger frame and / or the response frame. The control information included in the trigger frame and / or the response frame may include some / all of the fields illustrated in FIG. 12. For example, the trigger frame may include feedback / forwarding information, common control information, and per-user control information. For example, the response frame may include common control information.

[0190] The length field may or may not be included in the control information. If the length field is included, it may be set to a value indicating the length of the remaining fields excluding the length field.

[0191] The transmission information included in the trigger frame may correspond to common information to be transmitted to the opposing STA. For example, information related to IDC, MAP, DPS, NPCA, security enhancement, and / or information regarding A-control (e.g., BSR) may be included in the trigger frame (or request frame). Additionally, common control information and / or feature information may be included along with indication information indicating that the trigger / request frame includes information regarding the corresponding feature.

[0192] Common control information may also be referred to as common feature information.

[0193] Common control / feature information may correspond to control information for each feature and may be included as transmission information in the trigger frame.

[0194] Common control / feature information may also include information related to IDC, MAP, DPS, NPCA, security enhancements, etc., and / or information about A-control (e.g., BSR).

[0195] FIG. 13 is a diagram showing examples of configurations of common control / feature information according to the present disclosure.

[0196] Example 1-1

[0197] As in the example of Fig. 13(a), common control / feature information may include a length field and a presence bitmap field.

[0198] The length field may be replaced by a number of information field, or the length (number of information) field may be omitted.

[0199] The presence bitmap field may contain a bitmap whose length corresponds to the number of supported features, such as MAP, DPS, IDC, NPCA, and BSR. Each bit position in the bitmap may indicate whether the corresponding control information is included. Whether one or more pieces of control information are included may be indicated by the bitmap.

[0200] The presence bitmap may further include information about features corresponding to bit positions set to a specific value (e.g., 1). For example, the value of n may correspond to the number of values ​​of 1 in the presence bitmap.

[0201] In the example of Fig. 13(a), if the presence bitmap indicates that MAP control / feature information does not exist and that control / feature information for NDCA, DPS, IDC, and BSR exists, four control / feature information fields follow, and each control / feature information field may include subfield(s). In the example, the specific contents of the IDC control information are described below with reference to Fig. 14.

[0202] Example 1-2

[0203] As in the example of Fig. 13(b), common control / feature information may include a length field and an ID field.

[0204] The length field may be replaced by a number field of information. Alternatively, the length may be expressed as the number of octets or the number of specific units (e.g., 2-bit units, 4-bit units, etc.). Alternatively, the length field may be omitted depending on feature instructions (e.g., feature enable or feature disable) such as transmission information. Alternatively, the length field may be omitted if the length of each control information is fixed and not variable.

[0205] The ID field can be set to an identifier value defined for each feature. For example, the ID value of MAP is predefined as 1, the ID value of DPS is predefined as 2, the ID value of IDC is predefined as 3, and the ID value of NPCA is predefined as 4, so that each feature can be distinguished by its ID value.

[0206] A combination of an ID field and its control information (and / or feature information) may include one or more.

[0207] Example 1-3

[0208] As illustrated in the example of Fig. 13(c), common control / feature information may include a full length field, an ID field, a length field per ID, and a feature information field. For example, in the example of Fig. 13(b), a length field per ID may be added. The first length field may correspond to the full length field, and the length field following the ID field may correspond to a length field for feature information of the corresponding ID.

[0209] Example 2

[0210] This embodiment describes examples of feature information of common control information.

[0211] Example 2-1

[0212] IDC-related information may be included as an example of feature information for common control information. The IDC-related information may include one or more of the information described below.

[0213] IDC start time

[0214] IDC start time (ST) information may correspond to a value indicating the time interval from the current time to the time when the IDC SP starts, based on a predetermined unit (e.g., microseconds (ms), timing synchronization function (TSF), partial TSF, etc.).

[0215] IDC ST information can indicate when an IDC occurs, i.e. when unavailability occurs.

[0216] Unavailability may mean unavailability for the channel on which the STA operates or for some subchannels of the channel on which the STA operates (e.g., X 20MHz subchannels). That is, unavailability may not always mean unavailability for the channel on which the STA operates.

[0217] The IDC ST information can be indicated using the entire (e.g., the entire 8-octet-long information) or a portion (e.g., partial TSF) of the timestamp (or TSF) received from the AP or the AP itself. For example, in case of partial TSF, similar to the existing broadcast TWT, bit values ​​(or bit positions) starting from a specific bit value (or bit position) of the TSF up to X octets (e.g., 2 octets) can be used.

[0218] For example, an interval or duration (e.g., in microseconds) from the start or completion of transmission of a frame transmitting the current IDC ST information to the point at which IDC or unavailability occurs may be indicated as the IDC ST information.

[0219] Alternatively, the IDC ST may be indicated using the Duration field of the MAC header. For example, the value of the Duration field of the MAC header may be set to a value corresponding to the time interval or duration until the IDC ST. In this case, when the IDC ST is indicated through the Duration field of the MAC header, the start time information may be omitted from the IDC-related information (e.g., the IDC individual TWT parameter set).

[0220] Alternatively, the IDC ST may indicate the start time of an availability interval during which no unavailability due to the IDC occurs.

[0221] IDC duration

[0222] IDC duration information can correspond to the duration of the IDC. For example, the duration unit can be microseconds, or another unit may be used. The size of the duration information can be defined as less than 8 octets (e.g., 2 octets), depending on the application to which the IDC SP is applied.

[0223] For example, information about a specific unit size may be included together with the duration information. For example, information indicating 1us, 8us, 32us, or 64us as the unit size may be included, and this may be applied as the unit of the value indicated by the duration information. For example, if the value of the duration information is 1000 and the unit size information indicates 1us, 1ms may be indicated as the duration of the IDC SP. For example, if the value of the duration information is 1000 and the unit size information indicates 8us, 8ms may be indicated as the duration of the IDC SP.

[0224] For example, IDC duration information may be defined as a 2-octet size, such as the duration field of the MAC header, but the size is exemplary and may be smaller or larger.

[0225] For example, if an IDC ST exists, the IDC Duration indication may be omitted. In this case, the IDC Duration may be implicitly interpreted as the period from the IDC ST to the end of a specific period. For example, if an IDC ST is indicated within a TXOP, the end of the specific period may correspond to the end of the corresponding TXOP.

[0226] Alternatively, if the IDC ST indicates the start point of an availability interval, the IDC Duration may indicate the duration of that availability interval.

[0227] IDC interval

[0228] The IDC interval information may correspond to the time interval between repetitions of the IDC SP, when the IDC SP repeats periodically. For example, the interval unit may be microseconds, or another unit may be used. The size of the interval information may be defined as less than 3 octets (e.g., 2 octets), depending on the application to which the IDC SP is applied.

[0229] For example, information about a specific unit size may be included together with the interval information. For example, information indicating 1us, 8us, 32us, or 64us as the unit size may be included, and this may be applied as a unit of the value indicated by the interval information. For example, if the value of the interval information is 1000 and the unit size information indicates 1us, 1ms may be indicated as the interval between repeated IDC SPs. For example, if the value of the interval information is 1000 and the unit size information indicates 8us, 8ms may be indicated as the interval between repeated IDC SPs.

[0230] For example, IDC interval information may be defined as a 2-octet size, such as the duration field of the MAC header, but the size is exemplary and may be smaller or larger.

[0231] IDC continuity

[0232] IDC continuity information can indicate how long an IDC SP continues. For example, the number of IDC SP repetitions (e.g., an integer value) can be indicated as IDC continuity information.

[0233] Additionally or alternatively, as IDC continuity information, the entire duration including all IDC SP repetitions from the start time of the IDC SP (i.e., the duration until the end of the IDC SP repetitions, not the duration of one IDC SP) or the end time of the IDC SP repetitions (i.e., the point in time when the IDC SP repetitions end, not the end time of one IDC SP) may be indicated.

[0234] Alternatively, the number of beacon frames, TBTT, beacon interval, etc. may be indicated as IDC continuity information. For example, the number of times a beacon is transmitted within a period in which repetition continues from the time when the IDC SP is first generated / started may be indicated. Alternatively, the number of beacon intervals for which repetition of the IDC SP continues in units of beacon intervals from the time when the IDC SP is first generated / started may be indicated.

[0235] This IDC continuity information may be included in the IDC information when an IDC interval exists (i.e., when a predetermined interval exists between repetitions of the IDC SP).

[0236] IDC channel / BW(bandwidth)

[0237] IDC channel / BW (bandwidth) information can indicate the channel / BW in which IDC occurs. In other words, the channel / BW information can indicate the frequency resources in which IDC SP occurs or does not occur.

[0238] For example, IDC channel / BW information can be defined in bitmap format. For example, for the operating channel and / or bandwidth of an STA, a bitmap in units of 20MHz (sub)channels can be defined, and whether each 20MHz (sub)channel is available or unavailable due to an IDC event can be indicated through the value of each bit position in the bitmap.

[0239] Additionally or alternatively, since the BW of each STA may be different, BW information may be additionally indicated. For example, the BW may be indicated as one of 20MHz / 40MHz / 80MHz / 160MHz / 320MHz, and a bitmap having a number of bits corresponding to the number of 20MHz (sub)channels corresponding to the indicated BW may be adaptively configured.

[0240] IDC channel / BW information may indicate a limited BW within which an STA can transmit and receive (i.e., available) due to an IDC situation, in which case information about the IDC channel may not be included in the IDC-related information.

[0241] IDC NSS (number of spatial streams) / antenna

[0242] IDC NSS (number of spatial stream) / antenna information may include information indicating available (or unavailable) NSS and / or available (or unavailable) antenna index.

[0243] For example, available NSS information may indicate the number of available spatial streams. Depending on the value of available NSS information, the number of available spatial streams may be indicated even in an IDC situation, excluding spatial streams that are unavailable due to an IDC event or IDC situation.

[0244] For example, the available NSS information may indicate which NSS and / or antenna indices are available or unavailable in an IDC situation. For example, a bitmap may be utilized to indicate the availability / unavailability of each antenna bit by bit, starting from the lowest (or highest) antenna index, based on the most significant bit (MSB) or least significant bit (LSB) of the information.

[0245] Example 2-2

[0246] The information / fields / subfields of the various examples described above may vary depending on the situation in which they are included in the IDC-related information. For example, if the primary channel of the BSS to which the STA belongs is affected by an IDC event, the STA may not be able to use all channels within the BSS due to the IDC operation, and therefore, the IDC channel / BW information indicating specific frequency resources may not be included in the IDC-related information. Alternatively, if the IDC SP does not repeat periodically but occurs only temporarily, the IDC interval information and IDC continuity information may not be included in the IDC-related information. Therefore, the various methods described below can be applied to indicate whether specific information / fields / subfields are included (or exist) in the IDC-related information.

[0247] Figure 14 illustrates additional examples of IDC information fields according to the present disclosure.

[0248] For example, a presence field can be defined and used for each piece of information / field / subfield. If the value of the presence field for a specific piece of information is 1, the specific piece of information exists, and if the value is 0, the specific piece of information may not exist.

[0249] The presence field may also be defined in bitmap form. As in the example of Fig. 14(a), it can be assumed that the first bit of the presence bitmap corresponds to IDC start time information, the second bit corresponds to IDC duration information, and the third bit corresponds to IDC channel information. If the presence bitmap is set to 110xxxxx, the IDC information may include the IDC start time field and the IDC duration field, but may not include the IDC channel field. The remaining bits except for the number of bits corresponding to each piece of information in the presence bitmap may be reserved.

[0250] Next, the 1-bit fully unavalability field in the examples of FIG. 14 can indicate whether the STA is capable of transmitting or receiving on the operating channel due to IDC. For example, if the value is 1, information about the IDC channel may not be included.

[0251] Next, a 1-bit indication field may be defined and utilized to indicate periodicity. If the IDC SP is periodic and continuously repeats, the value of the periodicity field may be set to 1. If the IDC SP is generated only once, the value of the periodicity field may be set to 0. In this case, IDC interval information and IDC continuity information may not be included in the IDC-related information.

[0252] In the example of Fig. 14(b), if the value of the entire unavailable field is 0, it means that some of the data is unavailable (or partially available), and thus information such as IDC channels may be included. In addition, if the value of the periodicity field is 0, it means that the data corresponds to a non-repeating IDC SP, and thus the IDC start time and IDC duration fields are included, but the IDC interval and IDC continuity fields may not be included.

[0253] In the example of Fig. 14(c), a length field may be added to the IDC information field. When a new subfield is added to the IDC information, an STA that cannot recognize the new subfield may determine which field to ignore based on the value of the length field.

[0254] Additionally or alternatively, an IDC information field may be assigned an ID. This is to explicitly indicate that the field is an IDC information field, and any other ID value may be recognized by the STA as control information for the ID rather than the IDC information field. This ID field may also correspond to a control information field (which may include an IDC information field).

[0255] As shown in the example of Fig. 14(d), a generalized control information field may include one or more control information. For example, a general control information field may include the same control information or different control information. For example, an IDC information field and another information field may be included within a general control information field. The first field of the general control information field may indicate the number of control information, and for example, it may be assumed that two pieces of control information are included. It is assumed that an ID value of 0 is assigned to an IDC information field and an ID value of 1 is assigned to a BSR (buffer status report) information field. Therefore, an IDC information field including an ID field set to a value of 0 and a BSR information field including an ID field set to a value of 1 may be included within the general control information field.

[0256] Alternatively, the number field of control information may be omitted in the example of Fig. 14(d). Alternatively, the number field of control information may be configured in the form of an element that includes a length field.

[0257] Example 2-3

[0258] Other information that may be included in control information or feature information, other than the IDC-related information described above, is described below.

[0259] LLT (low latency traffic) information

[0260] When low latency traffic (LLT) occurs in a TXOP responder, LLT information can be defined for the purpose of notifying the TXOP holder of this. The TXOP holder, which receives the LLT information as feedback information, can provide various methods (e.g., TXOP sharing, trigger-based MU data transmission, etc.) to enable the TXOP responder to transmit LLT. The LLT information is not limited to information that the TXOP responder transmits to the TXOP holder, and can also be applied to notify other STAs of the occurrence of LLT by any STA.

[0261] The LLT information may be defined as a 1-bit indicator that indicates whether an LLT has occurred. Alternatively, the LLT information may be defined as an appropriate size greater than 1 bit to convey various additional information, such as LLT range requirements (e.g., transmission lifetime), LLT frame size, and the type of LLT information.

[0262] BSR Information

[0263] BSR (buffer status report) information can be defined to provide existing BSR information as control / feature / feedback information. This can be distinguished from the existing method in which the BSRP trigger frame requests a QoS null frame that includes BSR information in the A-Control field. For example, when a BSRP trigger frame is used as a trigger frame during an ICF or TXOP, the BSR information can be defined as one type of control / feature / feedback information to provide BSR information for responding to the BSRP together with other control / feature / feedback information.

[0264] The BSR information may include information included in a conventional BSR (e.g., an access category index (ACI) bitmap, a delta traffic identifier (TID), ACI high, a scaling factor, queue size high, and / or queue size all) and may further include BSR extension information. The BSR extension information may include, for example, an unscaled value of a TID for reporting a larger queue size, multiple TIDs, an additional control subfield for reporting a queue size larger than the maximum queue size that a QoS control frame can report when no identical TIDs are present in the MPDU, etc.

[0265] Cross-link power saving information

[0266] Cross-link power save information may correspond to information indicating entry / exit of power saving mode for the entire link.

[0267] In power management of a conventional multi-link device (MLD), power saving mode entry / exit can be indicated by setting the value of the power management (PM) subfield of the MAC header of a frame that can be transmitted on each link (i.e., per link) to 1 or 0. Even when all STAs affiliated with the MLD enter / exit the power saving mode, control / feature / feedback information indicating power saving mode entry / exit across the entire link can be defined in order to eliminate the overhead of indicating power strategy mode entry / exit through the value of the PM subfield of a frame transmitted on each link.

[0268] Power management information, such as cross-link power saving information, may include a link ID, a PM bit per link, and power saving scheduling information (e.g., time duration and / or duration) for each link. Alternatively, the link ID may be configured as a bitmap, and a PM bit may be indicated for each link(s) corresponding to PM enablement (e.g., indicated as 1) in the bitmap. In this case, scheduling information may be additionally listed sequentially only for the link(s) corresponding to PM enablement in the bitmap.

[0269] Alternatively, a bitmap of a link ID may be additionally indicated along with the existing PM subfield. In this case, the value indicated by the PM subfield may be commonly applied to the link(s) corresponding to the PM enable (e.g., indicated as 1) in the bitmap. For example, if the link IDs at the 3rd and 6th bit positions of the bitmap are set to 1, the value of the PM subfield may be commonly applied to link IDs 3 and 6.

[0270] In the examples described above, the common control / feature information may include control information that is commonly applied to each function. A single container (e.g., frame / element) may contain multiple pieces of common control / feature information.

[0271] Information per user

[0272] Per-user information may include user-specific information per feature to be conveyed to each opposing STA in the request / trigger frame. For example, in DPS, the recommended bandwidth when STA1 transitions from listen mode to active mode and the recommended bandwidth when STA2 transitions from listen mode to active mode may be conveyed as individual / different values ​​specific to each STA / user.

[0273] Example 3

[0274] This embodiment relates to delivered information (or control / feedback information) included in a trigger frame. For example, the trigger frame may correspond to an ICF, CRF, etc. The control and / or feature information of the feedback / delivery information may be configured according to one of the forms of the common control information and / or common feature information described above.

[0275] FIG. 15 is a diagram showing various examples of formats of transmission information (or control / feedback information) according to the present disclosure.

[0276] Example 3-1

[0277] Transmission information may be included in the common information field of the trigger frame.

[0278] The aforementioned transmission information can be defined using reserved bits / values ​​within the common information field of the trigger frame. For example, the reserved bits / values ​​can correspond to the EHT reserved bits (B56-B62) of the EHT variant common information field, additional reserved bits of the MU-RTS (e.g., UL length, UL space reuse field, etc.), etc. Through these bits / values, the petition information can be defined in bitmap format or index field format.

[0279] In the example of Fig. 15(a), F1, F2, F3, F4, ... may correspond to reserved bits / values ​​within the common information field of the trigger frame as described above. Each bit may correspond to a distinct feature (MAP, DPS, IDC, ...). When these bitmaps F1F2F3F4... are set to 1100..., MAP information and DPS information may be included in the feature information as transmission / feedback information.

[0280] The example in Figure 15(b) illustrates how the transmission information field is replaced with a special value (e.g., a specific value of AID12) or indicates an index of the transmission information. For example, if the value of the transmission information field is A, it may indicate that DPS information is included as transmission information in the trigger frame, and if the value is B, it may indicate that IDC information is included as transmission information.

[0281] Example 3-2

[0282] A common information field of a trigger frame may include a flag for transmission information, and transmission information indicated by the flag may be included in the user information field of the trigger frame.

[0283] In order to construct a trigger frame including the transmission information to be transmitted to the opposing STA, the flag of the aforementioned transmission information may be defined using reserved bits / values ​​within the common information field. For example, the reserved bits / values ​​may correspond to the EHT reserved bits (B56-B62) of the EHT variant common information field, additionally reserved bits of the MU-RTS (e.g., UL length, UL space reuse field, etc.), etc. One of these bits / values ​​may indicate whether the transmission information is included in another area of ​​the trigger frame.

[0284] When the value of the transmission information flag is set to a specific value (e.g., 1), the presence or absence of transmission information in a bitmap format (e.g., an example of FIG. 15(c)) or an index field format (e.g., an example of FIG. 15(d)) is included in a specific user information field of the trigger frame, and additional information (e.g., transmission / feedback information such as MAP, DPS, IDC, etc.) may be included in one or more other user information fields.

[0285] For example, the AID12 field (see FIG. 12) of a specific user information field may be set to a specific value, and some / all of the remaining bits of the specific user information field may be defined as information indicating the presence or absence of transmission information in bitmap format or index field format.

[0286] FIG. 16 is a diagram illustrating additional examples of formats of transmission information (or control / feedback information) according to the present disclosure.

[0287] For example, setting the value of the AID12 field of a user information field to a specific value may result in the user information field containing both information about the presence or absence of transfer information and actual transfer information (or control / feature / feedback information).

[0288] The AID12 field of a specific user information field may be set to a predefined value (or special AID) to indicate that the user information field contains common information for all features (i.e., information that is not user-specific). For example, this specific value (special AID) may be 2008.

[0289] Information indicating what kind of transmission information is included following the AID12 field may be included. In the example of Fig. 16(a), the bit corresponding to the IDC information in the bitmap indication field of B12-B16 is set to 1, and common information related to the IDC may be included subsequently. In other examples not shown, it may indicate that other types of control / feature / feedback information are included, and the corresponding control / feature / feedback information may be included subsequently.

[0290] Additionally, a trigger frame may include multiple user information fields containing common control / feature / feedback information. The AID12 fields of the multiple user information fields may all be set to the same specific value (e.g., 2008). The types of control / feature / feedback information of the multiple user information fields may be indicated as different types, and each user information field may include common control / feature / feedback information of different types.

[0291] As another example, referring to FIG. 16(b), a user information field including an AID12 field set to a specific value (e.g., 2008) indicates the type of the transfer information (e.g., a bitmap field), and the actual transfer information may be included in another user information field. In this case, a predefined specific value related to each type of the transfer information may be set as the value of the AID12 field of the corresponding user information field. For example, a first user information field including an AID12 field set to a DPS-related specific value may include DPS-related information, and a second user information field including an AID12 field set to an IDC-related specific value may include IDC-related information.

[0292] In the examples described above, the bitmap instruction field is only an example, and the field indicating the type of control / feature / feedback information in the form of the above-described index may also include the bitmap instruction field.

[0293] Referring to FIG. 16(c), the transmission information control field may correspond to a bitmap or index / ID-based information indicating what type of transmission information exists. The transmission information field may include the type of transmission information indicated to exist in the transmission information control field. The transmission information field may include one or more user information fields. For example, when multiple user information fields are included, the values ​​of the AID12 fields of the corresponding user information fields may all be set to the same specific value (e.g., 2008). For example, a first user information field may include a first type of transmission information, and a second user information field may include a second type of transmission information.

[0294] In this way, considering the size of the user information field, if the size of the transmission information is large, multiple user information fields having the same AID12 field value may sequentially include different types of transmission information. In order to configure the sequential user information fields, a continue bit may be defined in the user information field to indicate the presence of a subsequent user information field, or a length field may be defined in the front of the transmission information field to indicate the presence of a number of user information fields (e.g., user information fields having the same AID12 value)(s).

[0295] The examples described above may be applied when the inclusion of forwarding information is explicitly indicated by a forwarding information flag included in the common information field of the trigger frame, or when the inclusion of forwarding information is implicitly indicated by a specific AID12 value even when the forwarding information flag is omitted. For example, if there are user information fields that include an AID12 field set to a value greater than 2007 (e.g., 2008) as the value of the specific value (or special AID) described above, the user information field may be defined / interpreted as a user information field that includes forwarding information (e.g., common control / feedback information). This specific value may be defined as the same value for all user information fields that include forwarding information, or may be defined as a distinct value depending on the type of forwarding information.

[0296] Referring to Fig. 16(d), in addition to or instead of the common information field, the special user information field (if any), and the M (M is 1 or more) user information fields of the trigger frame, N (N is 1 or more, may be the same as or different from M) transfer user information fields may be included. The order of the fields in Fig. 16(d) is exemplary and not limiting. The transfer user information field corresponds to a user information field that includes control / feature / feedback information, and may also be referred to as a control user information field, a feature user information field, or a feedback user information field.

[0297] Each transfer user information field may include an AID12 field, a length field (optional), a transfer information type field, and a transfer information field. The transfer information may also be referred to as control information, feature information, or feedback information. The AID12 field may be set to a predefined specific value (e.g., 2008) to indicate that it includes transfer information. All N AID12 fields of N transfer user information fields may be set to the same specific value (e.g., 2008). The transfer information type field of the transfer user information field may indicate one of the types of transfer information to be included in the subsequent transfer information field (e.g., IDC (or unavailability), LL, DPS, MAP, NPCA, etc.). The transfer information type field may be defined in a bitmap manner or an index / ID manner. The transfer information field may include transfer information corresponding to the transfer information type field.

[0298] Example 4

[0299] The transmission information included in the trigger frame may include per-user information. For example, the transmission information of the aforementioned embodiment 3 corresponds to control / feature / feedback information, which is common information rather than user-specific information, and the user-specific information described below may correspond to control / feature / feedback information, which is user-specific information. In the examples described below, a user information field that includes transmission information (common information) that is not user-specific may be indicated as a transmission user information field (common). In contrast, a user information field that includes user-specific transmission information may be indicated as a transmission user information field (user-specific).

[0300] For example, a trigger frame containing transmission information may correspond to an ICF, CRF, etc.

[0301] FIG. 17 is a diagram illustrating additional examples of formats of transmission information (or control / feedback information) according to the present disclosure.

[0302] Example 4-1

[0303] Information (e.g., an existence bit or an existence value) indicating whether a user information field including transmission information for a specific STA exists can be defined. The existence bit can be defined as a bit indicating whether a user information field including user-specific transmission information exists, for example, B25 corresponding to a reserved bit in the format of an existing user information field (e.g., FIG. 12). Alternatively, a value indicating whether a user information field including user-specific transmission information exists (and / or a value indicating that a user information field including user-specific transmission information does not exist) can be defined using a value in the range of 91 to 126, which is a reserved value among the values ​​of the UL target reception power field at positions B32 to B38 of the format of an existing user information field (e.g., FIG. 12).

[0304] In the example of Fig. 17(a), a general (e.g., not including forwarding information) user information field for STA1 (e.g., the value of the AID12 field of the user information field is set to the ID / AID of STA1) may include a forwarding information presence field. If the forwarding information presence field (or the UL target reception power field) has a specific value, it may indicate that a per-user forwarding information field for STA1 exists within the trigger frame. If the forwarding information presence field (or the UL target reception power field) has another value, it may indicate that a per-user forwarding information field for STA1 does not exist within the trigger frame.

[0305] Alternatively, even if the general user information field does not include information about the presence of a user-specific forwarding user information field, if a user information field for STA1 additionally exists after the general user information field for STA1, the additionally existing user information field for STA1 may be implicitly indicated as being a forwarding user information field (e.g., a user information field including user-specific forwarding information for STA1).

[0306] As in the example of Fig. 17(b), the forwarding user information field containing user-specific (per-user) forwarding information for STA1 may be positioned consecutively next to the general (e.g., not including forwarding information) user information field for STA1.

[0307] As in the example of Fig. 17(c), the forwarding user information field containing user-specific (per user) forwarding information for STA1 may be positioned after the listing of user information fields for the STA(s) including STA1 is completed. For example, the forwarding user information field containing user-specific information may be positioned after the forwarding user information field containing common information.

[0308] In the example of Fig. 17(d), unlike the method in which the general user information field described with reference to Fig. 17(a) includes a bit / value that explicitly indicates the presence or absence of a user-specific transfer user information field, or the implicit indication method, the user information field itself may indicate whether or not the user-specific transfer information exists in the corresponding user information field. For example, if the value of the B25 bit of the user information field is a first value (e.g., 0), it may indicate that the corresponding user information field does not contain user-specific transfer information (e.g., corresponds to a general user information field), and if the value is a second value (e.g., 1), it may indicate that the corresponding user information field contains user-specific transfer information (e.g., corresponds to a user-specific transfer user information field). Alternatively, if the value of the UL Target Received Power field of B32-B38 of the user information field is a first value (e.g., one of the ranges 0-90), it may indicate that the corresponding user information field does not contain user-specific transmission information (e.g., corresponds to a general user information field), and if the value is a second value (e.g., one of the ranges 91-126), it may indicate that the corresponding user information field contains user-specific transmission information (e.g., corresponds to a user-specific transmission user information field).

[0309] FIG. 18 illustrates an example in which cross-link power saving information according to the present disclosure is included as feedback information.

[0310] When AP1 belonging to the AP MLD transmits a BSRP trigger frame to STA1 belonging to the Non-AP MLD, cross-link power saving information may be included in the control / feature / feedback information included in the multi-STA block ACK frame transmitted in response thereto. For example, the value of the PM bit may be set to 1 to indicate entering a doze state, and the link bitmap may indicate that the target corresponds to both links 1 and 2. When entering an awake state from the doze state, the cross-link power saving information may be included as transmission information in the control / feature / feedback information of the BSRP trigger frame. For example, the value of the PM bit may be set to 0 and the link bitmap may be set to (1,1). Accordingly, it may be indicated that the entire link is in an awake state. The BSRP trigger frame may include one or more additional pieces of information (e.g., IDC (or unavailability) information, MAP information, DPS information, etc.) corresponding to the aforementioned control / feedback information, in addition to cross-link power saving information. While the example assumes an AP to a non-AP STA, the same example can be applied to a non-AP STA to an AP, an AP to an AP, or a non-AP STA to a non-AP STA.

[0311] A method may be provided for providing new control / feature / feedback information of an STA, not supported by existing wireless LAN systems, to a counterpart STA via a trigger frame. Accordingly, unsolicited control / feature / feedback information may be provided to the counterpart STA, thereby enabling the counterpart STA to efficiently support the transmission of response frames and / or operations based on new features.

[0312] The embodiments described above are combinations of components and features of the present disclosure in a predetermined form. Each component or feature should be considered optional unless explicitly stated otherwise. Each component or feature may be implemented without being combined with other components or features. Furthermore, it is also possible to form 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 another embodiment or may be replaced with corresponding components or features of another embodiment. It is self-evident that claims that do not have an explicit citation relationship in the patent claims may be combined to form embodiments or incorporated as new claims through post-application amendments.

[0313] It will be apparent to those skilled in the art that the present disclosure may be embodied in other specific forms without departing from the essential characteristics thereof. Therefore, the above detailed description should not be construed as limiting in any respect, but rather as illustrative. The scope of the present disclosure should be determined by a reasonable interpretation of the appended claims, and all modifications within the scope of equivalents of the present disclosure are intended to be included within the scope of the present disclosure.

[0314] The scope of the present disclosure includes software or machine-executable instructions (e.g., an operating system, an application, firmware, a program, etc.) that cause operations according to the methods of various embodiments to be executed on a device or a computer, and a non-transitory computer-readable medium having such software or instructions stored thereon and executable on the device or computer. Instructions that can be used to program a processing system to perform the features described in the present disclosure can be stored on / in a storage medium or a computer-readable storage medium, and a computer program product including such a storage medium can be used to implement 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 optionally includes one or more storage devices remotely located from the processor(s). The memory or, alternatively, the non-volatile memory device(s) within the memory comprise a non-transitory computer-readable storage medium. The features described in this disclosure may be incorporated into software and / or firmware stored on any of the machine-readable media, which may control the hardware of the processing system and allow the processing system to interact with other mechanisms that utilize results according to embodiments of the present disclosure. Such software or firmware may include, but is not limited to, application code, device drivers, operating systems, and execution environments / containers.

[0315] The method proposed in this disclosure is described with a focus on examples applied to IEEE 802.11-based systems, but can be applied to various wireless LANs or wireless communication systems in addition to IEEE 802.11-based systems.

Claims

1. A step of generating a trigger frame including at least one first user information field including feedback information by a first station (STA); and A step of transmitting a PPDU (physical layer protocol data unit) including the trigger frame to a second STA by the first STA, A method wherein the first user information field includes a feedback type field and a feedback information field.

2. In paragraph 1, A method wherein the first user information field further includes an AID12 (association identifier 12) field.

3. In paragraph 2, A method wherein the first user information field includes the AID12 field, the feedback type field, and the feedback information field in that order.

4. In paragraph 1, The trigger frame includes a first first user information field and a second first user information field, A method wherein the value of the AID12 field of the first first user information field and the value of the AID12 field of the second first user information field are set to the same specific value.

5. In paragraph 4, The above same specific value is 2008, method.

6. In paragraph 1, A method wherein the feedback information field of the first first user information field includes unavailability related information based on the feedback type field of the first first user information field being set to the first value.

7. In paragraph 6, A method wherein the above unavailability related information includes at least one of start time information and duration information.

8. In paragraph 6, A method wherein the feedback information field of the second first user information field includes information related to one of low latency (LL), dynamic power saving (DPS), multi-access point (MAP), non-primary channel access (NPCA), or security enhancement, based on the feedback type field of the second first user information field being set to the second value.

9. In paragraph 1, A method wherein the feedback information included in the first user information field is not user-specific information or is common information.

10. In paragraph 1, A method wherein the trigger frame further includes one or more second user information fields.

11. In paragraph 10, A method in which the AID12 field of the second user information field is set to a value corresponding to the identification information of the second STA.

12. In paragraph 11, A method wherein the second user information field includes feedback information specific to the second STA.

13. In paragraph 1, The above trigger frame is a BSRP (buffer status report poll) trigger frame.

14. In paragraph 13, A method in which a multi-STA block ACK (acknowledgement) frame is transmitted from the second STA in response to the BSRP trigger frame.

15. In paragraph 14, A method in which the values ​​of fields for the GI (guard interval) and LTF (long training field) types of the above trigger frame are set to 3.

16. In paragraph 14, Based on the fact that the above trigger frame is an individually addressed BSRP trigger frame and the values ​​of the fields for GI and LTF types within the BSRP trigger frame are set to 3, A method wherein a physical layer protocol data unit (PPDU) transmitted in response to the BSRP trigger frame is a non-HT (non-high throughput) PPDU or a non-HT duplicate PPDU including the multi-STA block ACK frame.

17. One or more transmitters and receivers; and comprising one or more processors connected to said one or more transceivers, One or more of the above processors: Generating a trigger frame comprising one or more first user information fields including feedback information; and It is set to transmit a PPDU (physical layer protocol data unit) including the above trigger frame to the second STA through the one or more transceivers, The first user information field includes a feedback type field and a feedback information field.

18. A step of receiving a trigger frame including at least one first user information field including feedback information from a first STA by a second station (STA); and A step of transmitting a response frame in response to the trigger frame to the first STA by the second STA, A method wherein the first user information field includes a feedback type field and a feedback information field.

19. One or more transmitters and receivers; and comprising one or more processors connected to said one or more transceivers, One or more of the above processors: Receiving a trigger frame from a first station (STA) via one or more transceivers, the trigger frame including one or more first user information fields including feedback information; and It is set to transmit a response frame in response to the trigger frame to the first STA through the one or more transceivers, The second STA, wherein the first user information field includes a feedback type field and a feedback information field.

20. One or more processors; and A processing device comprising one or more computer memories operatively connected to said one or more processors and storing instructions for performing a method according to any one of claims 1 to 16 based on execution by said one or more processors.

21. One or more non-transitory computer-readable media storing one or more instructions that are executed by one or more processors to control the performance of a method according to any one of claims 1 to 16.

Images