Trigger-based feedback information response method and device in wireless LAN system

Abstract

Disclosed are a trigger frame-based feedback information response method and device in a wireless LAN system. A method according to an aspect of the present disclosure may comprise the steps in which: a first station (STA) transmits, to a second STA, a trigger frame including information related to feedback information; and the first STA receives, from the second STA, a response frame including the feedback information. On the basis that the trigger frame is a trigger frame of a specific format, the response frame may be a multi-STA block acknowledgement (ACK) frame.

Description

Method and device for responding to trigger-based feedback information in a wireless LAN system

[0001] The present disclosure relates to a method and device for responding to feedback information based on 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 responding to feedback information based on 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 the steps of: transmitting a trigger frame including information related to feedback information from a first station (STA) to a second STA; and receiving a response frame including the feedback information from the second STA by the first STA. Based on the trigger frame being a trigger frame of a specific format, the response frame may be a multi-STA block ACK (acknowledgement) frame.

[0007] A method according to an additional aspect of the present disclosure may include: receiving, by a second station (STA), a trigger frame from a first STA, wherein the trigger frame includes information related to feedback information; and transmitting, by the second STA, a response frame including the feedback information to the first STA. Based on the trigger frame being a trigger frame of a specific format, the response frame may be a multi-STA block ACK (acknowledgement) frame.

[0008] According to the present disclosure, a method and device for responding to feedback information based on 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 petition information formats according to the present disclosure.

[0026] FIG. 16 is a diagram illustrating examples of a multi-STA block ACK frame format according to the present disclosure.

[0027] FIG. 17 illustrates an example in which cross-link power saving information according to the present disclosure is included as feedback information.

[0028] FIG. 18 is a diagram illustrating additional examples of a multi-STA block ACK frame format according to the present disclosure.

[0029] FIG. 19 is a diagram illustrating additional examples of a multi-STA block ACK frame format according to the present disclosure.

[0030] FIG. 20 is a diagram showing examples of new control frames according to the present disclosure.

[0031] FIG. 21 is a diagram showing examples of formats of compressed BA frames according to the present disclosure.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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.

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

[0039] FIG. 1 illustrates a block diagram of a wireless communication device according to one embodiment of the present disclosure.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] In addition, the first device (100) and the second device (200) may additionally support various communication standards (e.g., 3GPP LTE series, 5G NR series standards, etc.) 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).

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

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

[0053] 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.

[0054] 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.

[0055] 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).

[0056] 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.

[0057] 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.

[0058] 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).

[0059] 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.

[0060] Data transmitted from one of the STA(s) associated with an AP to the STA address of that AP may always be received on an uncontrolled port and processed by an IEEE 802.1X port access entity. In addition, if the controlled port is authenticated, the transmitted data (or frame) may be forwarded to the DS.

[0061] In addition to the structure of the DS described above, an extended service set (ESS) may be established to provide wider coverage.

[0062] 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.

[0063] 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 restriction 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.

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

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] 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.

[0072] 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.

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

[0074] 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.

[0075] 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.

[0076] 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.

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

[0078] 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.

[0079] 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).

[0080] 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, ...).

[0081] 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.

[0082] 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 illustrates 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.

[0083] 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 such as DIFS or PIFS (Point coordination function IFS) elapses. 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.

[0084] 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.

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

[0086] 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.

[0087] 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.

[0088] 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.

[0089] 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.

[0090] 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.

[0091] 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.

[0092] 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.

[0093] 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.

[0094] 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.

[0095] 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.

[0096] 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 will be described later with reference to FIG. 7.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] 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.

[0101] The MAC header includes a Frame Control field, a Duration / ID field, an Address field, etc. The Frame Control field may include control information required for frame transmission / reception. The Duration / ID field may be set to 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.

[0102] 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).

[0103] FIG. 7 is a diagram illustrating examples of PPDUs defined in the IEEE 802.11 standard to which the present disclosure can be applied.

[0104] 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)).

[0105] 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).

[0106] 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)).

[0107] 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.

[0108] 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.

[0109] 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.

[0110] 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.

[0111] 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.

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

[0113] 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.

[0114] 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.

[0115] 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.

[0116] 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.

[0117] 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.

[0118] 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.

[0119] 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.).

[0120] 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.

[0121] 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.

[0122] 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.

[0123] 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.).

[0124] 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.

[0125] 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.

[0126] 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.

[0127] 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.

[0128] 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.

[0129] 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.

[0130] 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.

[0131] 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.

[0132] 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.

[0133] FIG. 8 is a drawing showing an exemplary format of a trigger frame to which the present disclosure can be applied.

[0134] 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.

[0135] 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.

[0136] 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.

[0137] Among the common information, the trigger dependent common info subfield may include information that is optionally included based on the trigger type.

[0138] 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.

[0139] A user information list contains zero or more user information fields. Figure 8 illustrates an example of an EHT variant user information field format.

[0140] 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.

[0141] 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.

[0142] 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.

[0143]

[0144]

[0145]

[0146] 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.

[0147] 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.

[0148]

[0149] Trigger-based feedback information response

[0150] 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.

[0151] 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.

[0152] FIG. 9 is a diagram illustrating an example of a trigger-based feedback information response to which the present disclosure may be applied.

[0153] 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.

[0154] 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.

[0155] 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.

[0156] 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.

[0157] 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.

[0158] 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.

[0159] FIG. 10 is a diagram illustrating an example of the operation of the first STA according to the present disclosure.

[0160] In step S1010, the first STA may transmit a trigger frame including information related to feedback information to the second STA.

[0161] In some examples, the trigger frame may be a trigger frame of a specific format (e.g., BSRP).

[0162] In some examples, the values ​​of the fields for the GI (guard interval) and LTF (long training field) types of the trigger frame may be set to 3.

[0163] For example, the trigger frame may be an individually addressed BSRP trigger frame, and the fields for GI and LTF types within the BSRP trigger frame may be set to 3. In this case, a PPDU transmitted in response to the BSRP trigger frame may be a non-HT PPDU or a non-HT duplicate PPDU including a multi-STA block ACK frame. Alternatively, a PPDU in response to a BSRP trigger frame in which the fields for GI and LTF types are not set to 3 may correspond to a TB PPDU.

[0164] In step S1020, the first STA can receive a response frame including feedback information from the second STA.

[0165] In some examples, if the trigger frame is a trigger frame of a particular format (e.g., a BSRP trigger frame), the response frame may be a multi-STA block ACK (acknowledgement) frame.

[0166] In some examples, the AID TID (association identifier traffic identifier) ​​information field of a multi-STA block ACK frame may be associated with one or more of the feedback type field or the feedback field.

[0167] In some examples, a multi-STA block ACK frame may include one or more feedback per AID TID info fields. For example, a first feedback per AID TID info field may include a first AID TID info field, a first feedback type field, and a first feedback field. A second feedback per AID TID info field may include a second AID TID info field, a second feedback type field, and a second feedback field.

[0168] In some examples, the value of the ACK type field within the AID TID information field may be set to 0, and the value of the TID field within the AID TID information field may be set to 13.

[0169] In some examples, the Feedback Type field may correspond to the last four bits (e.g., B12 to B15) of the Block ACK Start Sequence Control field of a multi-STA block ACK frame.

[0170] In some examples, the feedback type field may indicate one of a number of candidate feedback types. The candidate feedback types may include one or more types associated with one or more of unavailability, low latency (LL), in-device coexistence (IDC), dynamic power saving (DPS), multi-access point (MAP), non-primary channel access (NPCA), or security enhancement.

[0171] 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 transmit a trigger frame including information related to feedback information to a second STA through one or more transceivers (106), and to receive a response frame including feedback information from the second STA through 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).

[0172] For example, the memory (104) may store various information related to a trigger-based feedback response according to the present disclosure. The processor (102) may generate a frame containing information / fields related to the trigger-based feedback response, generate various RUs, generate a PPDU, and transmit the generated PPDU via the transceiver (106) based on the information stored in the memory (104). 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 the trigger-based feedback response, generate a frame / PPDU including the information / field, and transmit the frame / PPDU via the transceiver (106).

[0173] FIG. 11 is a drawing for explaining an example of the operation of a second STA according to the present disclosure.

[0174] In step S1110, the second STA can receive a trigger frame including information related to feedback information from the first STA.

[0175] In step S1120, the second STA may transmit a response frame including feedback information to the first STA.

[0176] In the example of Fig. 11, the details of the trigger frame format, response frame format, PPDU type including the response frame, etc. are the same as in the example of Fig. 10, so redundant descriptions are omitted.

[0177] 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 information related to feedback information from a first STA through one or more transceivers (206), and to transmit a response frame including the feedback information 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).

[0178] For example, the memory (204) can store various information related to a feedback response included in a 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 information / fields related to a feedback response, decode / parse a frame addressed to it based thereon, and transmit a response frame including feedback information based on the information related to the feedback response.

[0179] In the examples of FIGS. 10 and 11, the first STA may transmit one or more PPDUs / frames containing information related to feedback information (or solicited 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). The solicited information (or information related to feedback information) may correspond to information indicating which feedback information response is requested.

[0180] Additionally or alternatively, information related to feedback information (or petition information) may be included in the manner of bitmap instructions and / or bit indexes in the common information field of the trigger frame.

[0181] Additionally or alternatively, information related to feedback information (or petition information) may be indicated by a petition 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.

[0182] Additionally or alternatively, information related to feedback information (or petition information) may be bit-indicated in the form of a general response in the common information field of the trigger frame.

[0183] Additionally or alternatively, information related to feedback information (or petition information) may be bit-indicated in the general response and type form of the common information field of the trigger frame.

[0184] Additionally or alternatively, information related to feedback information (or petition information) may be included by redefining a special AID12 field in the user information field of the trigger frame to petition for feedback information related to a specific function.

[0185] Additionally or alternatively, information related to feedback information (or petition information) may not be explicitly included in the trigger frame, but may be implicitly included according to rules requesting a general response.

[0186] Additionally or alternatively, information related to feedback information (or petition information) may be indicated via the TRS control (A-control (aggregated-control) field) of QoS data.

[0187] Additionally or alternatively, the trigger frame may include information that determines the frame format or PPDU format to which the second STA will respond (e.g., TB PPDU format or non-HT (duplicate) PPDU format).

[0188] In the examples of FIGS. 10 and 11, the second STA may detect and receive one or more PPDUs / frames containing information (or request information) related to feedback information of a trigger frame. The second STA may also determine, through frame detection, whether to transmit in the IDC section of the first STA and its capabilities.

[0189] A second STA that detects the request information (or information related to feedback information) of a first STA may transmit a response frame including common control and / or feature information corresponding to the feedback information.

[0190] For example, the common control and / or feature information may include common control and / or feature information related to MAP, DPS, NPCA, IDC, security improvement, etc. to which the second STA will respond, and / or common control and / or feature information of existing control information (e.g., BSR).

[0191] For example, common control and / or feature information may be transmitted (e.g., transmitted in response to a trigger frame) via a multi-STA block ACK frame, a new IDCR (IDC report) A-control field in response to a trigger frame, multiple new IDCR (IDC report) A-control subfields in response to a trigger frame, an A-MPDU response frame that accommodates multiple types of A-control fields in response to a trigger frame, a new control frame in response to a trigger frame, a new action frame in response to a trigger frame, a new action frame that includes an A-control in the HT control field in response to a trigger frame, and / or a block ACK frame (e.g., a compressed BA frame).

[0192] 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.

[0193] The following examples describe a method for including feedback information in a response frame (e.g., a multi-STA block ACK frame) based on information related to feedback information included in a trigger frame (e.g., a BSRP trigger frame). The BSRP trigger frame and the multi-STA block ACK frame are merely exemplary, and the examples of the present disclosure may also be applied to trigger frames in other formats (or ICFs used at the start of a TXOP, or control request frames used at a point after the start of a TXOP) and / or response frames in other formats (or ICRs responding to ICFs, or control response frames responding to control request frames).

[0194] Example 1

[0195] The present embodiment relates to control information (e.g., information related to feedback information (or petition information), or feedback information) that may be included in a trigger-based response frame. The control information may include, for example, MAP, DPS, IDC, NPCA, security enhancement, and / or existing A-control (e.g., BSR).

[0196] FIG. 12 is a diagram showing an example of control information according to the present disclosure.

[0197] 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 request information, common control information, and per-user control information. For example, the response frame may include common control information.

[0198] 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.

[0199] The petition information included in the trigger frame may correspond to information specifying feedback information to be included in the response frame. The specific format of the petition information is described below.

[0200] Common control information may also be referred to as common feature information.

[0201] Common control / feature information may correspond to control information for each feature and may be included in a response frame in response to the request information in the trigger frame.

[0202] 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).

[0203] FIG. 13 is a diagram showing examples of configurations of common control / feature information according to the present disclosure.

[0204] Example 1-1

[0205] As in the example of Fig. 13(a), common control / feature information may include a length field and a presence bitmap field.

[0206] The length field may be replaced by a number of information field, or the length (number of information) field may be omitted.

[0207] 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.

[0208] 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.

[0209] 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.

[0210] Example 1-2

[0211] As in the example of Fig. 13(b), common control / feature information may include a length field and an ID field.

[0212] 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 enablement or feature disablement) in the petition information, etc. Alternatively, the length field may be omitted if the length of each control information is fixed and not variable.

[0213] 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.

[0214] A combination of an ID field and its control information (and / or feature information) may include one or more.

[0215] Example 1-3

[0216] 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.

[0217] Example 2

[0218] This embodiment describes examples of feature information of common control information.

[0219] Example 2-1

[0220] 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.

[0221] IDC start time

[0222] 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.).

[0223] IDC ST information can indicate when an IDC occurs, i.e. when unavailability occurs.

[0224] 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.

[0225] 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.

[0226] 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.

[0227] 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).

[0228] Alternatively, the IDC ST may indicate the start time of an availability interval during which no unavailability due to the IDC occurs.

[0229] IDC duration

[0230] 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.

[0231] 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.

[0232] 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.

[0233] 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.

[0234] Alternatively, if the IDC ST indicates the start of an availability interval, the IDC Duration may indicate the duration of that availability interval.

[0235] IDC interval

[0236] 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.

[0237] 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.

[0238] 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.

[0239] IDC continuity

[0240] 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.

[0241] 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.

[0242] 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.

[0243] 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).

[0244] IDC channel / BW(bandwidth)

[0245] 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.

[0246] 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.

[0247] 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.

[0248] 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.

[0249] IDC NSS (number of spatial streams) / antenna

[0250] IDC NSS (number of spatial stream) / antenna information may include information indicating available (or unavailable) NSS and / or available (or unavailable) antenna index.

[0251] 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.

[0252] 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.

[0253] Example 2-2

[0254] 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.

[0255] Figure 14 illustrates additional examples of IDC information fields according to the present disclosure.

[0256] 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.

[0257] 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.

[0258] 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.

[0259] 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.

[0260] 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.

[0261] 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.

[0262] 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).

[0263] 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.

[0264] 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.

[0265] Example 2-3

[0266] Other information that may be included in control information or feature information, other than the IDC-related information described above, is described below.

[0267] LLT (low latency traffic) information

[0268] 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.

[0269] 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.

[0270] BSR Information

[0271] 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.

[0272] 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.

[0273] Cross-link power saving information

[0274] Cross-link power save information may correspond to information indicating entry / exit of power saving mode for the entire link.

[0275] 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.

[0276] 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.

[0277] 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.

[0278] 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.

[0279] Example 3

[0280] This embodiment relates to feedback information (or solicited information) included in a trigger frame. For example, the trigger frame may correspond to an ICF, CRF, etc.

[0281] FIG. 15 is a diagram showing various examples of petition information formats according to the present disclosure.

[0282] Example 3-1

[0283] Petition information is included in the common information field of the trigger frame and can be defined as information that directly points to feedback information.

[0284] The aforementioned petition 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 reserved values ​​of the GI and LTF type subfields, 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. Through these bits / values, the petition information can be defined in bitmap format or index field format.

[0285] 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, ...).

[0286] An example of Fig. 15(b) illustrates how the value of the N-bit sized field indicates the index of (a combination of) feedback information. For example, a value of 0 in the N-bit sized index field may indicate that no feedback information is requested, 1 may indicate IDC information, 2 may indicate DPS information, ... 5 may indicate that both IDC and DPS information are requested as feedback information.

[0287] For example, the request information in bitmap format or index field format can be included in the EHT reserved fields (e.g., B56-B62) of the common information field of the trigger frame of FIG. 12. For example, in bitmap format, B56 corresponds to FCS, B57 corresponds to MAP, B58 corresponds to DPS, B59 corresponds to IDC, B60 corresponds to NPCA, and B61 and B62 can be reserved. Depending on the value or bit position of the corresponding field, the requested feedback information can be explicitly indicated. FCS may correspond to a new function / feature such as an intermediate frame check sequence (FCS).

[0288] Example 3-2

[0289] The common information field of the trigger frame may include a flag for petition information, and petition information indicated by the flag may be included in the user information field of the trigger frame.

[0290] The flags of the aforementioned petition information may be defined using reserved bits / values ​​within the common information field of the trigger frame. For example, the reserved bits / values ​​may correspond to reserved values ​​of the GI and LTF type subfields, 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. One of these bits / values ​​may indicate whether the user information field includes petition information.

[0291] When the value of the petition information flag is set to a specific value (e.g., 1), the user information field of the trigger frame may include petition information in bitmap format or index field format. For example, the AID12 field (see FIG. 12) of the user information field may be set to a specific value, and some / all of the remaining bits may be defined as petition information in bitmap format or index field format.

[0292] In the example of Fig. 15(c), the petition information flag is included in the common information field, and if a petition information bitmap field exists in the user information field, the value of the flag bit can be set to a value of 1, and if the bitmap field does not exist, the value can be set to a value of 0.

[0293] In the example of Fig. 15(d), the petition information flag is included in the common information field, and if the petition information index field exists in the user information field, the value of the flag bit can be set to a value of 1, and if the index field does not exist, the value can be set to a value of 0.

[0294] The value of the index field may be defined similarly to the example in Figure 15, or may be undefined if a flag field is applied, indicating that the value of the index field is missing information.

[0295] For example, the petition information flag field may be included in one bit (e.g., B56) position of the EHT reserved field of the common information field of the trigger frame of FIG. 12. For example, if the value of the petition information flag field indicates the presence of petition information, B0-B11 of the user information field of the trigger frame may correspond to the AID12 field, B12 to the FCS, B13 to the MAP, B14 to the DPS, B15 to the IDC, B16 to the NPCA, and B17-B39 may be reserved. Depending on the value or bit position of the corresponding field, the requested feedback information may be explicitly indicated.

[0296] For example, if petition information is included in the user information field, the value of the AID12 field may be set to one of the existing reserved values ​​(e.g., 2008-2044, 2047-4094) to indicate that it corresponds to a special user information field that includes petition information.

[0297] Example 3-3

[0298] Instead of specifying what feedback information is being requested, petition information may be defined as information requesting a general response.

[0299] Information requesting a general response can be defined using reserved bits / values ​​in the common information field of the trigger frame. For example, the reserved bits / values ​​can correspond to reserved values ​​of the GI and LTF type subfields, 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.). One of these bits / values ​​can be defined as a flag for whether a general response is requested.

[0300] For example, it may be indicated that a generic response frame of a particular format is requested, rather than a trigger-dependent response (e.g., a QoS null frame containing a BSR in response to a BSRP trigger frame). For example, various response frames, such as a new control response frame, a new action frame, and / or a block ACK (BA) frame, may be used as the generic response frame of the particular format. For example, a multi-STA block ACK frame may be transmitted as a response frame to a trigger frame when the generic response flags in the GI and LTF type fields of the trigger frame are set to particular values. The generic response flags may also be referred to as solicitation information flags.

[0301] Additionally or alternatively, a type field of a generic response may be included in the trigger frame. The generic response type field may be included in the trigger frame in addition to or instead of the generic response flag field. For example, if the value of the response frame type field included in the trigger frame is 0, it may be defined as a trigger-dependent frame (i.e., not a generic response) such as a conventional QoS null frame, if the value is 1, it may be defined as a multi-STA block ACK frame, if the value is 2, it may be defined as a compressed block ACK frame, if the value is 3, it may be defined as a control information action frame, etc. For example, if the value of the generic response type field included in the BSRP trigger frame transmitted by the first STA is 1, the second STA may transmit a multi-STA block ACK frame as a response frame. For example, if the value of the generic response type field included in the BSRP trigger frame transmitted by the first STA is 0, the second STA may transmit a QoS null frame including a BSR as a response frame.

[0302] Example 3-4

[0303] A specific value of AID12 in the User Information field of a trigger frame can be defined as indicating a request for specific control / feature / feedback information.

[0304] As described with reference to FIG. 12, when the value of the AID12 field is 2007, it is defined as a special user information field and has a different format from the general user information field. When the value of the AID12 field has a specific value corresponding to a specific feature, it can be defined as another special user information field containing information about the feature. For example, when the value of the AID12 field is set to 2006 (or one of the previously reserved values ​​2008-2044, 2047-4094), it can indicate that it is a special user information field (e.g., an IDC user information field) containing IDC-related information.

[0305] As illustrated in the example of Fig. 15(e), the IDC user information field may include all or some of the illustrated subfields. The IDC user information field may be positioned subsequent to the common information field, subsequent to the existing special user information field (AID12=2007), or preceding the user-specific user information field(s).

[0306] Assuming that the AID12 field contains a request for IDC-related information when its value is 2006, a 1-bit IDC information request field with a value of 1 can indicate that IDC-related information is requested, and a 0 can indicate that IDC-related information is not requested.

[0307] Alternatively, IDC-related information may be subdivided to include the type of IDC-related information in the petition information. For example, the type of petition information may be limited considering the size of the response frame. For example, as in the example of Fig. 15(f), the size of the IDC information request type field may be defined as 4 bits. Accordingly, if the value of the IDC information request type field is 0, all IDC-related information is requested, if the value is 1, IDC time information is requested, if the value is 2, IDC channel information is requested, and if the value is 3, IDC spatial stream information is requested. Values ​​4-14 of the IDC information request type field may be reserved, and if the value is 15, no information is requested.

[0308] Alternatively, the IDC information request type field may be configured as a bitmap. Accordingly, one or more combinations of sub-information of IDC-related information may be requested. For example, the LSB to B0 of the IDC information request type field may be mapped to all IDC-related information, B1 to IDC time information, B2 to IDC channel information, and B3 to IDC spatial stream information. For example, a value of 0b1100 in the IDC information request type field may indicate that both IDC channel information and IDC spatial stream information are requested together.

[0309] Whether these IDC user information fields are included in the trigger frame can be indicated by the presence field of the common information field of the trigger frame. For example, the presence field of the common information field can be defined using the reserved values ​​of the GI and LTF type subfields, the EHT reserved bits (B56-B62) of the EHT variant common information field, and additionally reserved bits of the MU-RTS (e.g., UL length, UL space reuse field, etc.).

[0310] Alternatively, information indicating whether IDC information is requested, such as in the example of FIG. 15(e), may be defined using 1 bit of the reserved bits / values ​​of the common information field of the trigger frame. Alternatively, information indicating the IDC information request type, such as in the example of FIG. 15(f), may be defined using 4 bits of the reserved bits / values ​​of the trigger frame. For example, the reserved bits / values ​​of the common information field of the trigger frame may correspond to reserved values ​​of the GI and LTF type subfields, 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.

[0311] Alternatively, instead of including an IDC information request (type) field in the trigger frame, a dedicated trigger frame type (or variant) for IDC-related information requests may be defined. For example, a value of the trigger type subfield within the common information field of the trigger frame may correspond to a basic trigger frame, ..., 3 to an MU-RTS trigger frame, 4 to a BSRP trigger frame, .... If the value of this trigger type subfield is one of 9-15 (e.g., 9), the trigger frame may be defined as an IDC trigger frame.

[0312] The IDC trigger frame may not include the trigger-dependent common information field and the trigger-dependent user information field. Alternatively, the IDC trigger frame may include the trigger-dependent common information, and the trigger-dependent common information may include the IDC information request type field (4 bits in size).

[0313] Although the above example is for a trigger frame for a petition for IDC related information, trigger frames for petitions for other control / feature / feedback information (e.g., MAP, DPS, NPCA, security enhancements, etc.) can be defined in a similar manner.

[0314] Example 3-5

[0315] Rules may also be defined that implicitly petition for a general response without explicitly specifying petition information in the trigger frame.

[0316] Even if the trigger frame does not include information explicitly indicating a request for IDC-related information and / or information explicitly indicating a general response, as in the examples described above, a response frame in a format different from that of a response frame to a conventional trigger frame, such as a new control frame response, a new action frame, and / or a block ACK frame, may be requested.

[0317] For example, when a trigger frame or a trigger frame of a specific format is transmitted as a signaling according to enable / disable of each feature, a new control frame response, a new action frame, and / or a block ACK frame may be transmitted in response thereto. For example, when mutual enablement of IDC operation between devices is performed through management signaling (e.g., a new action frame), IDC-related information may be provided by being included in the response frame even if the trigger frame does not specify whether IDC-related information is requested.

[0318] Alternatively, a multi-STA block ACK frame (rather than a QoS null frame containing a conventional BSR) may be transmitted in response to a trigger frame such as BSRP. For example, such a multi-STA block ACK frame may include feedback information (e.g., IDC-related information, MAP control information, NPCA control information, etc.).

[0319] In this way, as a response to a trigger frame, a general response frame (e.g., a multi-STA block ACK frame, a block ACK frame, a new control frame response, a new action frame, etc.) may be implicitly requested.

[0320] Example 3-6

[0321] The TRS control field of the QoS data frame (e.g., contained in the A-Control field) may also contain petition information.

[0322] Although the above examples describe the petition information included in the trigger frame, an extended response frame, such as a general response frame, may be petitioned as a response frame to a QoS data frame by utilizing the reserved bits of the TRS control field of the QoS data frame, although it is not a trigger frame.

[0323] For example, in a UL MU transmission that may be a response to a QoS data frame, a length greater than the previously defined length may be allowed. This allows an STA receiving the QoS data frame to recognize that it may include additional information in the response frame. While UL data symbols may be adjusted without this instruction, the response frame may include control / feature / feedback information (e.g., IDC information fields, etc.) only if the STA(s) receiving the QoS data know that such adjustment is permitted by the peer STA(s). In other words, if the STA(s) receiving the QoS data arbitrarily increases the symbol length in the absence of this instruction, misalignment of the UL MU transmission may occur if the peer STA(s) do not permit it.

[0324] An example format of a TRS control field including a petition information flag is shown in the example of FIG. 15(g).

[0325] B25, previously reserved in the TRS control field, can be newly defined as a petition information flag field (or a field with another name, such as control information request, control information petition, etc.). Accordingly, the request for control / feature / feedback information, such as IDC-related information, can be indicated through the TRS control field.

[0326] The petition information flag may also be used for specific features. For example, if the petition information flag is defined as an IDC information flag and set to a specific value (e.g., 1), the response frame according to the TRS control field may include IDC-related information along with BA information. In this case, a response frame such as a multi-STA block ACK may be used, which may include both BA information and IDC-related information.

[0327] Example 3-7

[0328] The format of the frame responding to the trigger frame or the format of the PPDU containing the response frame may be indicated through the petition information.

[0329] The existing trigger frame is defined as requesting a TB PPDU format including a response frame. In the present disclosure, the response frame of the trigger frame may be requested to be included in a non-HT PPDU or non-HT duplicate PPDU format rather than a TB PPDU. The non-HT (duplicate) PPDU may have a format similar to MU-RTS / CTS, which may provide improved protection for hidden nodes. In addition, the trigger frame may be defined to request a response from a single STA, rather than requesting a response from multiple STAs.

[0330] For example, in the format of the trigger frame of FIG. 12, the format of the response frame / PPDU for the trigger frame can be indicated / determined by using a combination of the value of the RA (receiver address) field of the MAC header and the value of other information (e.g., the PHY version identifier field of the special user information).

[0331] If the user information list of the trigger frame includes multiple user information fields, the RA field may be set as a broadcast MAC address. In this case, the response frame to the trigger frame may be determined as a PPDU format capable of UL MU transmission, such as a TB PPDU. Alternatively, if the user information list of the trigger frame includes one user information field, the RA field may be set as the unicast MAC address of the corresponding STA.

[0332] The examples below may apply whether the RA field is set to a unicast MAC address (i.e., individually addressed trigger frames), or not (e.g., the RA field is set to a broadcast MAC address).

[0333] For example, if the PHY version identifier field of the special user information field is set to a value greater than or equal to 1 and not 0, the response frame to the trigger frame may be determined to be in a non-TB PPDU format (e.g., non-HT PPDU, non-HT duplicate PPDU).

[0334] As another example, the trigger frame may include information explicitly indicating the PPDU format in which the response frame of the trigger frame will be included. For example, by using reserved bits / values ​​of the common information field of the trigger frame (e.g., EHT reserved bits (B56-B52), additional reserved bits of MU-RTS (e.g., UL length, UL space reuse field, etc.)), if the value is 0, it may be determined as a TB PPDU format, and if the value is 1, it may be determined as a non-TB PPDU (e.g., non-HT PPDU, non-HT duplicated PPDU) format. Alternatively, in order to indicate more diverse response PPDU formats, multiple bits / values ​​may be used, such that if the value is 0, it indicates a TB PPDU format, if the value is 1, it indicates a non-HT PPDU format, and if the value is 2, it indicates a non-HT duplicated PPDU format.

[0335] As another example, the PPDU format including the response frame may be determined based on the values ​​of the GI and LTF type fields of the common information field of the trigger frame (e.g., the GI and HE / EHT-LTF type fields, or the GI and HE / UHR-LTF type fields of FIG. 12). For example, when the values ​​of the GI and LTF type fields are set to 0x11 or decimal 3, the PPDU transmitted in response to the trigger frame may be determined to be a non-HT PPDU format or a non-HT duplicate PPDU format.

[0336] If a non-TB PPDU, such as a non-HT PPDU format or a non-HT duplicate PPDU format, is requested, all fields after the GI and LTF type fields in the common information field of the trigger frame may be defined as reserved fields or may be used for request information.

[0337] In the examples described above, the trigger frames containing the petition information or implicitly requesting a specific response are intended to request a specific type of response frame, so legacy devices (e.g., STAs conforming to standards prior to IEEE 802.11be) may not understand the information. Legacy devices are defined to transmit only responses corresponding to the type of each trigger frame. For example, a legacy device that receives a BSRP trigger frame containing the petition information or implicitly requesting a specific response will respond with a QoS null frame containing a BSR, but a new device that understands the petition information in the BSRP trigger frame or the request for the implicit specific response may respond with a different response frame (e.g., a multi-STA block ACK frame) according to the new rules. To address this issue, an STA transmitting a trigger frame may set the value of the UL length field in the trigger frame to include the longest length among responses from multiple STAs, taking into account situations where the length of the response may vary to support backward compatibility with legacy devices (e.g., the length of the response frame may be longer if requested control / feature / feedback information is included).

[0338] Among the examples described above, IDC-related information as examples of control / feature / feedback information may be replaced with other control / feature / feedback information such as MAP, DPS, NPCA, and security improvement.

[0339] Example 4

[0340] The present embodiment is for a response frame including control / feature / feedback information based on a trigger frame.

[0341] In Example 1, control / feature / feedback information included in a response frame was described, and in this embodiment, a format of a response frame including one or more such control / feature / feedback information is described.

[0342] Example 4-1

[0343] Control / feature / feedback information may be included in a multi-STA block ACK frame.

[0344] A multi-STA block ACK frame is a frame that can be transmitted to one or more STAs, and various examples of control / feedback information included in a multi-STA block ACK frame are described below.

[0345] FIG. 16 is a diagram illustrating examples of a multi-STA block ACK frame format according to the present disclosure.

[0346] In the example of Figure 16, the BA information field of the multi-STA block ACK frame may include one or more per AID TID information. The per AID TID information may be<AID, TID> It can be repeated over tuples.

[0347] As in the example of FIG. 16(a), the format of the information field per AID TID may include an AID TID information field (2 octets), a block ACK start sequence control field (0 or 2 octets), and a block ACK bitmap field (0, 4, 8, 16, or 32 octets). The AID TID information field (2 octets) may include an AID11 field (11 bits), an ACK type field (1 bit), and a TID field (4 bits). The block ACK start sequence control field may include a fragment number field (4 bits) and a start sequence number field (12 bits).

[0348] Example 4-1-1

[0349] To indicate that the multi-STA block ACK frame contains control / feature / feedback information, a specific value in the AID TID information (association identifier traffic identifier info) field of the multi-STA block ACK frame may be used.

[0350] The presence or absence of control / feature / feedback information in a response frame can be indicated by setting one or more of the AID11 field, ACK type field, and TID field included in the AID TID information field of a multi-STA block ACK frame to a specific value that is distinct from the previously defined values.

[0351] For example, the value of the ACK type field may be set to 0, and the value of the TID field may be set to one of the values ​​8 to 15 (e.g., 13).

[0352] Additionally or alternatively, the value of the AID11 field may be set to a specific value. For example, when a non-AP STA transmits to the AP, the value of the AID11 field may be set to a value other than 0 (e.g., 1 or 2008). In this case, the ACK type field and the TID field may be set to any values. Since the non-AP STA transmits a multi-STA block ACK frame only to the AP, the AP can determine whether control / feature / feedback information exists in the response frame through the specific AID value.

[0353] Additionally or alternatively, if the AP transmits a multi-STA block ACK frame to one or more non-AP STAs, the value of the AID11 field may be set to a specific value (e.g., one of 0, 2008, and 2044). Alternatively, if the AP transmits a multi-STA block ACK frame to only one STA, the AID11 field may be set to the AID value of the corresponding STA.

[0354] When the AID TID information field is set to a specific value as in the examples described above, instead of the block ACK start sequence control field and the block ACK bitmap field in the example of Fig. 16(a), control / feature / feedback information may be included as in the example of Fig. 16(b). The size of the field may correspond to the size of the control / feature / feedback information.

[0355] Within a TXOP that is initiated through an exchange of RTS of an AP (e.g., TXOP holder) and CTS of an STA (e.g., TXOP responder), an STA that receives a data frame (e.g., multi-TID A-MPDU) from the AP can transmit a multi-STA block ACK. As an example of control / feature / feedback information included in the multi-STA block ACK frame, IDC-related information can be included, and an IDC operation can be performed for a specific time interval at a specific point in time according to the IDC-related information.

[0356] As in the example of Fig. 16(b), when the ACK type is set to a value of 0 and the TID is set to a value of 14, it can be indicated that the information field per the corresponding AID TID includes control / feature / feedback information.

[0357] As another example, the size of the block ACK bitmap field may be determined using the value of the fragment number field while the AID11 field is set to a specific value, the ACK type field is set to a value of 0, and the value of the TID field is set to an arbitrary value (e.g., 0). Accordingly, control / feature / feedback information may be included by utilizing the start sequence number field (12 bits) of the block ACK start sequence control field and the block ACK bitmap field. Additionally, if the available field size is larger than the control / feature / feedback information, the remaining bits may be reserved. Accordingly, when a multi-STA block ACK frame is transmitted to multiple STAs, an STA that cannot recognize the presence of control / feature / feedback information may recognize the length of the information field per each AID TID in the same way as in the conventional manner without causing a problem.

[0358] As in the example of Fig. 16(c), for example, when the fragment number field is set to B3=0, B2-B1=3, B0=0 (i.e., 0110), a block ACK bitmap size of 4 octets is applied, so control / feature / feedback information less than the sum of the sizes of the start sequence number field (12 bits) and the block ACK bitmap size (4 octets) may be included. Additionally or alternatively, the value of the AID11 field may be set to a specific value to indicate that the control / feature / feedback information is included.

[0359] In order to indicate that the control / feature / feedback information is included in the examples described above, the value of the AID11 field may be set to a specific value. In addition, along with the AID TID-specific information field including the control / feature / feedback information, the existing AID TID-specific information field (e.g., including the Block ACK Start Sequence Control and / or the Block ACK Bitmap field as in FIG. 16(a)) may be transmitted together in a single multi-STA block ACK frame.

[0360] As another example, it can be assumed that a BSRP trigger frame from an AP is transmitted to STA1, a legacy device, and STA2, a UHR device, and when STA2 recognizes the occurrence of an IDC event, STA1 responds with a BSR, and STA2 responds with a multi-STA block ACK frame. In addition, the BSRP trigger frame transmitted by the AP may include the aforementioned request information, requesting feedback of IDC-related information. In this case, the multi-STA block ACK frame transmitted by STA2 may include the IDC-related information as control / feedback information. For example, as in the example of FIG. 16(d), when the AID11 field is set to a value of 2046, the ACK type and TID fields are each set to 0, and the fragment number field is set to B3=0, B2-B1=0, B0=0 (i.e., 0000), the block ACK bitmap size is 8 octets, so the control / feature / feedback information including IDC-related information can be configured with a size of 76 bits, which is the sum of the 12 bits of the start sequence number field and the 8 octets of the block ACK bitmap field. The IDC-related information in the control / feature / feedback information can include, for example, a length field, a presence bit field, and an IDC information field. The control / feature / feedback information may further include BSR information.

[0361] As another example, it can be assumed that a QoS data frame including a TRS control field from an AP is transmitted to STA1, a legacy device, and STA2, a UHR device, and when STA2 recognizes the occurrence of an IDC event, STA1 responds with a BSR and STA2 responds with a multi-STA block ACK frame. In addition, the TRS control frame transmitted by the AP may include the aforementioned petition information to request feedback of IDC-related information. In this case of responding with a block ACK frame for a single TID, a multi-STA block ACK frame may be responded instead of a block ACK response frame, and the block ACK information of STA2 may be included in the Information 1 field per AID TID, and the Control / Feature / Feedback information may be included in the Information 2 field per AID TID. As in the example of Fig. 16(c), when the AID11 field is set to a value of 2046, the ACK type and TID fields are each set to 0, and the fragment number field is set to B3=0, B2-B1=3, B0=0 (i.e., 0110), the block ACK bitmap size is 4 octets, so the control / feature / feedback information including IDC-related information can be configured with a size of 44 bits, which is the sum of 12 bits of the start sequence number field and 4 octets of the block ACK bitmap field. The IDC-related information in the control / feature / feedback information can include, for example, a length field, a presence bit field, and an IDC information field.

[0362] As another example, it can be assumed that a basic trigger frame from an AP is transmitted to STA1, a legacy device, and STA2, a UHR device, and thus STA1 and STA2 perform UL MU data transmission via TB PPDU. The AP can respond to this UL MU data transmission with a multi-STA block ACK frame to STA1 and STA2. If the AP recognizes the occurrence of an IDC event before transmitting the multi-STA block ACK frame, the multi-STA block ACK frame may additionally include IDC-related information as control / feature / feedback information. For example, the Information 1 field per AID TID may include block ACK information for STA1, the Information 2 field per AID TID may include block ACK information for STA2, and the Information 3 field per AID TID may include IDC-related information as control / feature / feedback information (as in the examples of FIGS. 16(b) to 16(d)).

[0363] Example 4-1-2

[0364] To indicate that a multi-STA block ACK frame contains control / feature / feedback information, a specific value of the fragment number field of the block ACK start sequence control field of the multi-STA block ACK frame may be used.

[0365] The fragment number field of the block ACK sequence control field included in the information field per AID TID of a multi-STA block ACK frame can be set to a specific value that is distinct from the previously defined values ​​to indicate the presence or absence of control / feedback information in the response frame. For example, the fragment number field can be set to B3=1, B2-B1=3, B0=1 (i.e., 1111).

[0366] As in the example of Fig. 16(e), when the fragment number field is set to a specific value, a control / feature / feedback information field may be included instead of the block ACK bitmap field. The size of the field may correspond to the size of the control / feature / feedback information. Alternatively, the size of the existing block ACK bitmap field (e.g., 4 octets) may be used, and the remaining bits other than the control / feature / feedback information within that size may be reserved.

[0367] For the aforementioned embodiments 4-1-1 and 4-1-2, the presence of control / feature / feedback information (e.g., IDC-related information) can be indicated using one of the reserved bits. Accordingly, the presence of IDC-related information can be notified to the receiving STA in advance. As in the examples (a) or (b) of Fig. 14, the presence of control / feature / feedback information can be indicated when an ID is used. The presence of control / feature / feedback information is indicated, and if present, it can be known that IDC-related information is included through a specific ID mapped to the control / feature / feedback information.

[0368] Alternatively, among the fields included in the BA control field, one of the fields not used by non-DMG STAs, such as No Memory Kept, Memory Configuration Tag, and Management Ack, may be used as a field indicating the presence or absence of control / feedback information.

[0369] Alternatively, a specific value (e.g., 0 or 2) of the TID_INFO field within the BA control field may be used as a value to indicate the presence or absence of control / feature / feedback information.

[0370] If a BA information field exists in a multi-STA block ACK frame, control / feature / feedback information may be located after the BA information field.

[0371] Alternatively, if control / feature / feedback information is included within a multi-STA block ACK frame, the BA information field may not be included. In this case, one of the reserved bits, a specific field of the BA control field, etc. may be used to indicate whether the BA information field is included.

[0372] Multi-STA block ACK frames are not only sent as a response to BSRP trigger frames or data, but can also be used to send control / feature / feedback information, as a response to a Block ACK Request (BAR) frame (e.g., multi-TID BAR), or a trigger frame of another variant (e.g., basic, BQRP, etc.).

[0373] The example of Fig. 16(f) is for a case where various control / feature / feedback information is included. For example, IDC related information, LLT information, and BSR information may be included. In the AID TID information field, for example, the AID11 field may be set to 2008. The value of the fragment number field in the block ACK start sequence control field may be set to 0000, and accordingly, the size of the block ACK bitmap field may be 8 octets (i.e., 64 bits). Instead of the start sequence number field of the block ACK start sequence control field, a field indicating the total number (e.g., 3) or total length of control / feature / feedback information (e.g., 4 bits) may be included, and the remaining bits (e.g., 8 bits) may be reserved. The block ACK bitmap field (64 bits) may include IDC related information, LLT information, and BSR information. For example, the first type field may be set to a value indicating that it is feedback information about unavailability, and may subsequently contain unavailability feedback information. The second type field may be set to a value indicating that it is LLT information, and may subsequently contain LLT information. The third type field may be set to a value indicating that it is BSR information, and may subsequently contain BSR information.

[0374] FIG. 17 illustrates an example in which cross-link power saving information according to the present disclosure is included as feedback information.

[0375] 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 in the control / feature / feedback information included in the BSRP trigger frame or in the multi-STA block ACK frame in response thereto. 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 indicate that the entire link is in an awake state. Although this example assumes an AP to a non-AP STA, the same example can be applied to non-AP STA to AP, AP to AP, or non-AP STA to non-AP STA.

[0376] A multi-STA block ACK frame including cross-link power saving information may be a variation of the example of FIG. 16(f), where the fragment number field is set to 0010 and the block ACK bitmap field has a size of 16 octets (i.e., 128 bits). In addition, the length (or number of information) field may be set to values ​​corresponding to four pieces of information (e.g., IDC, LLT, BSR, and cross-link power saving information). Accordingly, among the 128 bits corresponding to the block ACK bitmap, the first to third types may correspond to unavailability feedback, LLT, and BSR information. Additionally, the fourth type may be set to a value indicating that it is cross-link power saving information, and may include a PM bit (1 bit) and a link bitmap (16 bits). The remaining bits among the 128 bits may be reserved.

[0377] Example 4-1-3

[0378] To indicate that a multi-STA block ACK frame contains control / feature / feedback information, a specific value of the AID11 field within the AID TID information field of the multi-STA block ACK frame may be used.

[0379] FIG. 18 is a diagram illustrating additional examples of a multi-STA block ACK frame format according to the present disclosure.

[0380] As in the example of Fig. 18, the values ​​of different AID11 fields can be assigned to different control / feature / feedback information. For example, the value 2008 of AID11 can be assigned to IDC-related information (or unavailability feedback information), 2009 to LLT information, and 2010 to BSR information. For example, unavailability feedback information can be included in the block ACK bitmap field position of the information 3 field per AID TID where the value of AID11 is set to 2008. For example, LLT information can be included in the block ACK bitmap field position of the information 4 field per AID TID where the value of AID11 is set to 2009. For example, BSR information can be included in the block ACK bitmap field position of the information 5 field per AID TID where the value of AID11 is set to 2010.

[0381] FIG. 19 is a diagram illustrating additional examples of a multi-STA block ACK frame format according to the present disclosure.

[0382] In the example of Fig. 19, the ACK type field in the AID TID information field is set to 0, and the value of the TID field is set to 13, thereby indicating that the information field per AID TID includes control / feature / feedback information.

[0383] Additionally, the block ACK sequence control field may include information indicating the type of control / feature / feedback information. For example, the first 4 bits (B0-B3) of the block ACK sequence control field may correspond to a fragment number field, the remaining 8 bits (B4-B11) may be reserved, and the last 4 bits (B12-B15) may be defined as a type (e.g., feedback type) field of the control / feature / feedback information.

[0384] For example, if the ACK Type field is set to 0, the TID field is set to 13, and the type field of the last 4 bits of the block ACK sequence control field is the first value (e.g., 0), then the information field per AID TID may include unavailability feedback information following the block ACK start sequence control field.

[0385] For example, if the ACK Type field is set to 0, the TID field is set to 13, and the type field of the last 4 bits of the block ACK sequence control field is the second value (e.g., 1), the information field per AID TID may include LLT (low latency traffic) feedback information following the block ACK start sequence control field.

[0386] For example, if the ACK Type field is set to 0, the TID field is set to 13, and the type field of the last 4 bits of the block ACK sequence control field is the third value (e.g., 2), the information field per AID TID may include CLPS (cross-link power save) feedback information following the block ACK start sequence control field.

[0387] Example 4-2

[0388] A new in-device coexistence report (IDCR) A-Control field may be defined to respond to trigger frames.

[0389] In order to include control / feature / feedback information corresponding to the petition information included in the trigger frame in the examples described above, a new A-control field may be defined. To this end, one of the previously reserved values ​​(e.g., 10) among the available values ​​of the control ID field of the A-control field may be defined as the control ID value indicating IDCR.

[0390] The IDCR control subfield may include one or more of the start time field (16 bits B0-B15), duration (16 bits B16-B31), channel (16 bits B32-B47), maximum Rx NSS (4 bits B48-B51), and reserved bits (B52-B55). The size of each field is exemplary and other sizes may be applied. For example, if the value indicated by the start time field uses only 9 bits of the TSF, the size of the start time field may be 9 bits.

[0391] The IDCR control subfield may be included in QoS data frames, QoS null frames, etc.

[0392] Similar to the A-control field containing IDC related information, such as the IDCR control subfield, an A-control field containing other control / feature / feedback information and the value of the corresponding control ID field can be defined.

[0393] When the AP transmits a trigger frame to STA1, STA2, and STA3, the value of the user information field may be set to a specific value (e.g., AID=2007) to indicate that IDC-related information is requested. When STA1, STA2, and STA3 transmit a response frame to the trigger frame, STA2, which recognizes the occurrence of an IDC event, may include an A-control field corresponding to the IDCR control subfield in the response frame (e.g., a QoS null frame). Accordingly, the AP may not transmit a DL MU PPDU to STA2, where an IDC event will occur, but may transmit DL MU PPDUs to STA1 and STA3 in RU1 and RU2, respectively. Thereafter, STA1 and STA3 may transmit a block ACK frame to the AP.

[0394] Example 4-3

[0395] Several new IDC A-Control fields may be defined that respond to trigger frames.

[0396] If all IDC-related information is included in a single IDCR control subfield, the control information may exceed the header size. Therefore, multiple control subfields with different control ID values ​​related to IDC can be defined, and these control subfields can be combined to form IDC-related information.

[0397] For example, among the available values ​​of the control ID field of the A-control field, one of the previously reserved values ​​(e.g., 10) may be assigned as a control ID value corresponding to the in-device coexistence start time (IDCS) control subfield, another (e.g., 11) may be assigned as a control ID value corresponding to the in-device coexistence duration (IDCD) control subfield, and another (e.g., 12) may be assigned as a control ID value corresponding to the in-device coexistence channel and NSS (IDCCN) control subfield.

[0398] For example, the IDCS control subfield may include a start time field (16 bits B0-B15) and reserved bits (B16-B25). The IDCD control subfield may include a duration (16 bits B0-B15) and reserved bits (B16-B25). The IDCCN control subfield may include a channel (16 bits B0-B15), maximum Rx NSS (4 bits B16-B19), and reserved bits (B20-B25). The size of each field is exemplary, and other sizes may be applied. For example, if the value indicated by the start time field uses only a 9-bit portion of the TSF, the size of the start time field may be 9 bits. The reserved bits of the IDCS, IDCD, and IDCCN control subfields may be omitted. Alternatively, IDC channel information and IDC NSS information can be separated and defined as control subfields with different control ID values.

[0399] The IDCS, IDCD, and IDCCN control subfields may be included in QoS data frames, QoS null frames, etc. Multiple IDC-related control subfields may be combined within the maximum size of the A-control field.

[0400] As another example, the control ID field for IDCR may be assigned only one value (e.g., 10) and subtype information may be included in the A-control field to distinguish different IDC information. For example, the subtype value 0 may be defined to correspond to the start time, the value 1 to the duration, the value 2 to the channel, the value 3 to the maximum Rx NSS, and the value 4 to the channel and the maximum Rx NSS. For this purpose, the subtype field may be defined to have a size of 3 bits. Alternatively, the subtype field may be defined to have a size of 2 bits or 4 bits, and the number of IDC-related information that can be supported by the bits of the corresponding size may be defined.

[0401] For example, an IDCR control subfield corresponding to subtype 0 may include a subtype (3 bits of B0-B2), a start time (16 bits of B3-B18), and a reserved bit (B19-B25). An IDCR control subfield corresponding to subtype 2 may include a subtype (3 bits of B0-B2), a channel (16 bits of B3-B18), and a reserved bit (B19-B25). An IDCR control subfield corresponding to subtype 3 may include a subtype (3 bits of B0-B2), a maximum Rx NSS (4 bits of B3-B6), and a reserved bit (B7-B25). The IDCR control subfield corresponding to subtype 4 may include subtype (3 bits of B0-B2), channel (16 bits of B3-B18), maximum Rx NSS (4 bits of B19-B22), and reserved bits (B23-B25).

[0402] Similar to the A-control field containing IDC related information, such as various IDCR control subfields, A-control fields containing other control / feature / feedback information and values ​​of the corresponding control ID fields can be defined.

[0403] Example 4-4

[0404] Describes the structure of an A-MPDU response frame that accommodates various types of A-control fields.

[0405] For example, to simultaneously transmit various types of IDC-related information in the example described above, a response frame can be constructed using an A-MPDU. It may be necessary to simultaneously transmit multiple types of IDC-related information in response to the IDC request type of the petition information included in the trigger frame. For this purpose, a frame such as an A-MPDU can be utilized.

[0406] For example, an operation between an AP and STA1, STA2, and STA3 as in the example of Embodiment 4-2 may be assumed. In this embodiment, a BSRP trigger frame from the AP may include request information for IDC-related information. A response frame (e.g., a QoS null frame) may include control subfields of various subtypes of IDCR in the A-control field. After receiving the trigger frame, STA2, which recognizes the occurrence of an IDC event, may include IDC-related information in the A-control field of the QoS null frame. Here, an IDCR of a first subtype (e.g., including a start time) may be included in the A-control field of a first A-MPDU subframe, and an IDCR of a second subtype (e.g., including a duration) may be included in the A-control field of a second A-MPDU subframe. Additionally, BSR information may be included in the A-control field of a third A-MPDU subframe. Accordingly, the AP may not transmit a DL MU PPDU to STA2 where an IDC event occurs, but may transmit DL MU PPDUs to STA1 and STA3 in RU1 and RU2, respectively. STA1 and STA3 may then transmit block ACK frames to the AP.

[0407] Example 4-5

[0408] A new control frame can be defined as a response frame based on a trigger frame. This new control frame can be defined as a response frame that includes control / feature / feedback information, or can be defined as a response frame that does not include control / feature / feedback information.

[0409] For example, since the values ​​0000-0001, 1111 are reserved in the subtype within the Frame Control field of the MAC header, one of these values ​​can be defined as a new control frame (e.g., an IDC frame).

[0410] FIG. 20 is a diagram showing examples of new control frames according to the present disclosure.

[0411] As in the example of Fig. 20(a), the IDC frame may include an IDC control field and an IDC information field. The IDC frame may also include some or all of the fields illustrated.

[0412] The IDC control field may include an existence bitmap of each subfield within the IDC information field. The IDC information field may include one or more of the following information: IDC start time, duration, channel, interval, continuity, maximum Rx NSS, etc.

[0413] The example in Fig. 20(b) shows an example in which an A-control field including a response according to a trigger type is included in an IDC frame.

[0414] The first two bits (B0-B1) of the A-control field are reserved, B2-B5 correspond to the control ID field, and the rest can be defined to contain variable control information. For example, in the case of BSR, the first two bits are reserved, the value of the control ID of B2-B5 is set to 3 (0b11), and B6-B31 can contain the ACI bitmap, delta TID, ACI high, scaling factor, queue size high, and queue size all subfields.

[0415] If the IDC frame includes an A-control field, the presence or absence of the A-control field may be indicated in the IDC control field. The A-control field may include different control subfields depending on the type of trigger frame. For example, if a BSRP trigger frame includes petition information, the A-control field of the IDC frame responding to it may include BSR. Alternatively, if an MU-RTS trigger frame includes petition information, a new control frame (e.g., an IDC frame) other than a CTS may be used as the response frame. In this case, the IDC frame may include IDC information, but the A-control field may be omitted.

[0416] As in the example of Fig. 20(c), a new control frame responding to a trigger frame may include one or more A-control fields. For this purpose, an A-control presence field may be defined.

[0417] Each bit of the A-control presence field can correspond to each control ID in order from the MSB or the LSB, or in any order. If the corresponding bit is set to 1, it can indicate the presence of the corresponding A-control field. If multiple bits are set to 1, the A-control list field can contain multiple A-control fields. For example, if the value of the bit mapped to the BSR of the A-control presence field and the value of the bit mapped to the OM (operating mode) are 1, the A-control list can contain both the BSR and the OM. .

[0418] Similar to the new control frame containing IDC related information, such as the IDC frame, new control frames containing other control / feature / feedback information can be defined.

[0419] Example 4-6

[0420] A new action frame can be defined as a response frame based on the trigger frame. This new action frame can also be defined as a response frame that includes control / feature / feedback information.

[0421] An action frame can contain a category field and an action details field. Since the values ​​33 and 38-125 are reserved for the category field, one of these values ​​(e.g., 38) can be defined as a new action frame (e.g., an IDC frame).

[0422] IDC action field values ​​can be defined according to the category value. For example, a value of 0 in the IDC action field may indicate an IDC response, a value of 1 may indicate an IDC and A-control information response, and a value of 2 may indicate an A-control information response.

[0423] If the value of the IDC action field is 0, the body of the action frame contains an IDC response, and the IDC action field format can be composed of a category in the first order and one or more IDC pieces of information in the second order.

[0424] If the value of the IDC action field is 1, the body of the action frame includes IDC response and A-control information, and the IDC action field format can be composed of a category in the first order, one or more IDC information in the second order, and one or more A-control information in the third order.

[0425] If the value of the IDC action field is 2, the body of the action frame includes A-control information, and the IDC action field format can be composed of a category in the first order and one or more A-control information in the second order.

[0426] The element IDs for the elements of IDC information and the elements of A-control information can be defined as follows.

[0427] Element Element ID Element ID Extension Extensible Fragmentable...IDC Information 255117 Yes No A-Control Information 255118 Yes No...

[0428] An IDC information element may include an element ID field (1 octet), a length field (1 octet), an element ID extension field (1 octet), and an IDC information field (variable size). The IDC information field of an IDC information element may include a length field (1 octet), a control field (1 octet), and IDC information (variable size). The IDC information field may include one or more IDC-related information, and the presence or absence of each IDC-related information may be indicated in the control field. Accordingly, the value of the length field may vary. An A-control information element may include an element ID field (1 octet), a length field (1 octet), an element ID extension field (1 octet), and an A-control information field (variable size). The A-control information field of an A-control information element may be defined as having the first two bits (B0-B1) reserved, B2-B5 corresponding to the control ID field, and the rest including variable control information. For example, in the case of BSR, the first two bits are reserved, the value of the control ID of B2-B5 is set to 3 (0b11), and B6-B31 may include ACI bitmap, delta TID, ACI high, scaling factor, queue size high, and queue size all subfields.

[0429] IDC information may also be configured as one of the A-control information (e.g., see the example where the value 10 of the aforementioned control ID corresponds to IDCR, or where the values ​​10, 11, and 12 of the control ID correspond to IDCS, IDCD, and IDCCN). In this case, the element ID for the IDC information is not defined, and unlike the example in Table 3, the element ID of the A-Control information may be defined as 255, the element ID extension as 117, and the extendable as YES.

[0430] When transmitting a BSRP trigger frame, the AP may set the value of the field indicating a general response frame among the petition information to 1 and transmit it. STA1 and STA3, which are legacy devices, cannot recognize the petition information and thus may respond with a QoS null frame including a BSR in response to the BSRP trigger frame from the AP. STA2, which is a UHR device, may recognize the petition information and respond with an IDC frame. STA2, which recognizes the occurrence of an IDC event, may include IDC information and a BSR in the aforementioned IDC frame. Accordingly, the AP may not transmit a DL MU PPDU to STA2, where an IDC event will occur, but may transmit a DL MU PPDU to STA1 and STA3 in RU1 and RU2, respectively. Thereafter, STA1 and STA3 may transmit a block ACK frame to the AP.

[0431] In the examples described above, a new control frame or action frame containing IDC information may be transmitted unsolicited by a device that recognizes the occurrence of an IDC event to a counterpart device. For example, an STA may recognize the occurrence of an IDC event at the time it acquires transmission rights and transmit the IDC information in a new control frame or action frame to the counterpart STA (e.g., an AP). In this case, the AP can know in advance the IDC event occurrence period of the STA and can initiate data transmission through an RTS / CTS exchange with the STA after the period.

[0432] Similar to the new action frame containing IDC related information, such as the IDC frame, new action frames containing other control / feature / feedback information can be defined.

[0433] Example 4-7

[0434] A new action frame can be defined that includes A-control information within the HT control field as a response frame based on the trigger frame.

[0435] Similar to the aforementioned embodiment 4-6, an IDC frame may be defined as a new action frame. Unlike embodiment 4-6, the IDC frame of the present embodiment may include A-control information in the HT control field of the action frame, and the IDC information may be included in the body of the action frame.

[0436] For example, the category value can be defined as one of the reserved values ​​(e.g., 38). A value of the IDC action field of 0 may correspond to the inclusion of an IDC response. The IDC action field format may include a category in the first order and one or more IDC information in the second order. The element ID of the IDC information may be defined as 255, and the element ID extension may be defined as 117. The IDC information element may include an element ID (1 octet), a length field (1 octet), an element ID extension field (1 octet), and an IDC information field (variable size). The IDC information field of the IDC information element may include a length field (1 octet), a control field (1 octet), and IDC information (variable size). The IDC information field may include one or more IDC-related information, and the presence or absence of each IDC-related information may be indicated in the control field. Accordingly, the value of the length field may vary.

[0437] Unlike the IDC information included in the body of the action frame, the A-control information is included in the A-control area of ​​the HT control field of the action frame, and the information type may vary depending on the trigger frame type. For example, the BSR A-control field may be included in the HT control area of ​​the IDC frame, which is a new action frame responding to the BSRP trigger frame, and the IDC information may be included in the body of the IDC frame.

[0438] Example 4-8

[0439] Control / feature / feedback information, such as IDC related information, may also be included in compressed block ACK (BA) frames.

[0440] Since the compressed BA frame is a frame that can be transmitted to one STA, various examples including control / feature / feedback information are described below.

[0441] FIG. 21 is a diagram showing examples of formats of compressed BA frames according to the present disclosure.

[0442] Example 4-8-1

[0443] The presence of control / feature / feedback information can be indicated through one of the reserved bit(s) of the BA control field of the compressed BA frame. In the case where an ID is used, as in the example of Fig. 14(a), the presence of control / feature / feedback information can also be indicated. In this case, the presence of control / feature / feedback information is indicated, and if present, the inclusion of IDC information can be indicated through a specific ID mapped to the control / feature / feedback information.

[0444] Alternatively, among the fields included in the BA control field, one of the fields not used by non-DMG STAs, such as No Memory Kept, Memory Configuration Tag, and Management Ack, may be used as a field indicating the presence or absence of control / feedback information.

[0445] Control / feature / feedback information may be located after the BA information field in a compressed BA frame.

[0446] As shown in the example of Fig. 21(a), the reserved bit (B0) of the BA control field of the compressed BA frame can indicate the presence or absence of control / feature / feedback information. If control / feature / feedback information exists, the control / feature / feedback information field may be included following the BA information field.

[0447] When an AP transmits data to an STA and the STA transmits a compressed BA frame in response, if the STA recognizes the occurrence of an IDC event, it may include IDC information in the compressed BA frame.

[0448] IDC information is only an example, and various other control / feature / feedback information may be included in the compressed BA frame.

[0449] Example 4-8-2

[0450] The presence of control / feature / feedback information can be indicated by utilizing a specific value in the fragment number field of the block ACK start sequence control field of the compressed BA frame.

[0451] For example, certain unused or reserved values ​​may be used in the fragment number field (e.g., B3=1, B2-B1=3, B0=1 (i.e., 1111)).

[0452] When the fragment number field is set to a specific value, control / feature / feedback information may be included instead of the block ACK bitmap subfield. The size of the field may be the control / feature / feedback information. Alternatively, the size of the field may be the same as the size of the existing block ACK bitmap field. For example, if the block ACK bitmap field size is 8 octets, the remaining bits except for the control / feature / feedback information may be reserved.

[0453] As in the example of Fig. 21(b), when the value of the fragment number field is set to 1111, control / feature / feedback information may be included subsequently. The compressed BA frame may also include existing BA information along with the control / feature / feedback information. When the AP transmits data to the STA and the STA transmits a compressed BA frame to the AP in response, if the STA recognizes the occurrence of an IDC event, the STA may transmit a compressed BA frame including IDC information.

[0454] Alternatively, if the compressed BA frame includes control / feature / feedback information, the BA information field may not be included. In this case, whether the compressed BA frame includes the BA information field may be indicated through the fragment number field, reserved bits of the BA control field, etc.

[0455] Compressed BA frames can be used not only in response to data, but also as a response to BAR frames, compressed BAR frames, BSRP trigger frames, basic trigger frames, and BQRP trigger frames, and compressed BA frames containing control / feature / feedback information.

[0456] When using a compressed BA frame as a response frame to another request frame (e.g., a frame that does not request block ACK information), such as a BSRP trigger frame, the value of the BA type may be set to a reserved value (e.g., one of 0, 4, 5, 9, 12-15) or a reserved bit of the BA control field (e.g., one of B0, B5-B8) may be used to indicate that control / feature / feedback information is included, in which case the BA information field may be omitted.

[0457] Although the response frame containing control / feature / feedback information in the various examples described above is described as being transmitted in response to a request frame, the same response frame may also be transmitted unsolicited. For example, in the case of SU transmission, since it is an individually addressed frame, even if the format and size are different, it can be transmitted in this way if the other STA can understand that the control / feature / feedback information is additionally included.

[0458] A method for providing new control / feature / feedback information not supported by existing wireless LAN systems through various response frames can be developed. This allows for efficient provision of new feedback information to UHR STAs that recognize new response frames, while maintaining the format of existing response frames to prevent malfunctions in legacy STAs.

[0459] 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.

[0460] 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.

[0461] 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.

[0462] 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

A step of transmitting a trigger frame including information related to feedback information by a first station (STA) to a second STA; and A step of receiving a response frame including the feedback information from the second STA by the first STA, A method wherein the response frame is a multi-STA block ACK (acknowledgement) frame based on the trigger frame being a trigger frame of a specific format. In the first paragraph, A method wherein the trigger frame of the above specific format is a BSRP (buffer status report poll) trigger frame. In the first paragraph, A method in which the AID TID (association identifier traffic identifier) ​​information field of the above multi-STA block ACK frame is associated with at least one of the feedback type field and the feedback field. In the third paragraph, The value of the ACK type field in the above AID TID information field is set to 0, A method in which the value of the TID field in the above AID TID information field is set to 13. In the third paragraph, The above feedback type field corresponds to the last four bits of the block ACK start sequence control field of the multi-STA block ACK frame. In the third paragraph, A method wherein the multi-STA block ACK frame includes one or more feedback per AID TID info fields. In paragraph 6, The first feedback AID TID information field includes a first AID TID information field, a first feedback type field, and a first feedback field, A method wherein the second feedback AID TID per information field includes a second AID TID information field, a second feedback type field, and a second feedback field. In the third paragraph, A method wherein the candidate of the above feedback type includes one or more types related to one or more of unavailability, low latency (LL), in-device coexistence (IDC), dynamic power saving (DPS), multi-access point (MAP), non-primary channel access (NPCA), or security enhancement. In the first paragraph, 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. In the first paragraph, Based on the fact that the trigger frame of the above specific format 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. 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: Transmitting a trigger frame containing information related to feedback information to a second station (STA) via one or more transceivers; and A response frame including the feedback information is set to be received from the second STA through the one or more transceivers, The first STA, based on the trigger frame being a trigger frame of a specific format, wherein the response frame is a multi-STA block ACK (acknowledgement) frame. A step of receiving a trigger frame including information related to feedback information from a first STA by a second station (STA); and A step of transmitting a response frame including the feedback information to the first STA by the second STA, A method wherein the response frame is a multi-STA block ACK (acknowledgement) frame based on the trigger frame being a trigger frame of a specific format. 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 including information related to feedback information from a first station (STA) through one or more transceivers; and A response frame including the feedback information is set to be transmitted to the first STA through the one or more transceivers, The second STA, based on the trigger frame being a trigger frame of a specific format, wherein the response frame is a multi-STA block ACK (acknowledgement) frame. 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 10 based on execution by said one or more processors. One or more non-transitory computer-readable media storing one or more instructions that control execution by one or more processors to perform a method according to any one of claims 1 to 10.

Images