Method and device for operation considering IDC in wireless LAN system

Abstract

The present disclosure relates to an improved wireless LAN system. The present disclosure presents a method and a device for operation considering IDC in order to improve the reliability of traffic in an improved wireless LAN system. Specifically, the present disclosure presents parameters and detailed operation procedures for IDC quiet operation.

Description

Operating method and device considering IDC in wireless LAN system

[0001] The present disclosure relates to a wireless local area network (WLAN) system. Specifically, the present disclosure relates to an operating method and device that take into account in-device coexistence (IDC) in a WLAN system.

[0002] Wireless LAN (WLAN) systems are evolving for various purposes, such as improving transmission rates, increasing bandwidth, enhancing reliability, reducing errors, and reducing latency. The Institute of Electrical and Electronics Engineers (IEEE) publishes the 802.11 standard specification for WLAN systems, and the technology described in the 802.11 standard specification can be called WiFi (or Wi-Fi, Wireless Fidelity).

[0003] Wi-Fi technology has evolved over several generations of the 802.11 standard. For example, the 802.11ac standard addresses improvements for very high throughput (VHT), the 802.11ax standard addresses improvements for high efficiency (HE), and the 802.11be standard addresses improvements for extreme high throughput (EHT).

[0004] Meanwhile, technologies to provide a more improved wireless communication environment in wireless LAN systems are being discussed, and various technologies are being proposed and researched in response to the demand to further increase the reliability of wireless LAN systems.

[0005] This disclosure proposes a method and device for operating a device that considers IDC to ensure traffic reliability in a wireless LAN system. Specifically, this disclosure proposes procedures for a device to request, respond to, and report IDC-aware operations. Furthermore, this disclosure proposes a frame structure for IDC-aware operations.

[0006] The technical objectives to be achieved in the present disclosure are not limited to those mentioned above, and other technical tasks not mentioned can be considered by a person having ordinary skill in the art to which the present invention pertains from the embodiments of the present invention described below.

[0007] A method performed by a station (STA) according to an embodiment of the present disclosure may include the steps of transmitting, to an access point (AP), a first frame including an in-device coexistence (IDC) quiet request for an IDC quiet period, wherein a first control field of the first frame includes a value indicating the IDC quiet request and a first content field of the first frame includes at least one parameter for the IDC quiet period; receiving, from the AP, a second frame including an IDC quiet response to the first frame, wherein a second control field of the second frame includes a value indicating the IDC quiet response and a second content field of the second frame includes a status code field related to the IDC quiet response; and supporting and operating a wireless access technology other than the WLAN in the IDC quiet period based on the second frame.

[0008] According to an embodiment of the present disclosure, a method performed by an access point (AP) may include the steps of: receiving, from a station (STA), a first frame including an in-device coexistence (IDC) quiet request for an IDC quiet period, wherein a first control field of the first frame includes a value indicating the IDC quiet request and a first content field of the first frame includes at least one parameter for the IDC quiet period; transmitting, to the STA, a second frame including an IDC quiet response to the first frame, wherein a second control field of the second frame includes a value indicating the IDC quiet response and a second content field of the second frame includes a status code field related to the IDC quiet response; and performing an operation for the STA in the IDC quiet period based on the second frame, taking into account a wireless access technology other than the WLAN.

[0009] An STA according to one embodiment of the present disclosure comprises: at least one transceiver; at least one processor communicatively coupled to the at least one transceiver; And at least one memory communicatively coupled to the at least one processor and storing instructions, wherein the instructions are executed individually or in any combination by the at least one processor, so that the STA: transmits a first frame including an IDC quiet request for an in-device coexistence (IDC) quiet period to an AP (access point), wherein a first control field of the first frame includes a value for indicating the IDC quiet request and a first content field of the first frame includes at least one parameter for the IDC quiet period, receives a second frame including an IDC quiet response to the first frame from the AP, wherein a second control field of the second frame includes a value for indicating the IDC quiet response and a second content field of the second frame includes a status code field related to the IDC quiet response, and based on the second frame, transmits a second frame including an IDC quiet request to an access point other than the WLAN in the IDC quiet period. It can be configured to support and operate other wireless access technologies.

[0010] An AP according to one embodiment of the present disclosure comprises: at least one transceiver; at least one processor communicatively coupled to the at least one transceiver; And at least one memory communicatively coupled to the at least one processor and storing instructions, wherein the instructions are executed by the at least one processor individually or in any combination, so that the AP: receives from a station (STA) a first frame including an IDC quiet request for an in-device coexistence (IDC) quiet period, wherein a first control field of the first frame includes a value for indicating the IDC quiet request and a first content field of the first frame includes at least one parameter for the IDC quiet period, transmits to the STA a second frame including an IDC quiet response to the first frame, wherein a second control field of the second frame includes a value for indicating the IDC quiet response and a second content field of the second frame includes a status code field related to the IDC quiet response, and based on the second frame, determines whether to transmit a second frame other than the WLAN in the IDC quiet period. It may be configured to perform operations for the STA taking into account other wireless access technologies.

[0011] According to the various embodiments proposed in this disclosure, the reliability of traffic transmission and reception in a wireless LAN system can be improved. Furthermore, by simplifying the procedures for improving reliability, the efficiency of device operation can also be improved.

[0012] FIG. 1 illustrates a configuration of a device for wireless communication according to one embodiment of the present disclosure.

[0013] FIG. 2 illustrates an exemplary structure of a wireless LAN system related to the present disclosure.

[0014] Figure 3 illustrates a link setup process related to the present disclosure.

[0015] Figure 4 illustrates a backoff operation related to the present disclosure.

[0016] FIG. 5 illustrates a frame transmission operation based on CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) in connection with the present disclosure.

[0017] FIG. 6 illustrates an exemplary format of a frame used in a wireless LAN system related to the present disclosure.

[0018] FIG. 7 illustrates an exemplary format of a physical layer protocol data unit (PPDU) of a wireless LAN system related to the present disclosure.

[0019] FIG. 8 illustrates another exemplary format of a PPDU of a wireless LAN system related to the present disclosure.

[0020] FIG. 9 illustrates the QTP (quiet time period) operation of a wireless LAN system related to the present disclosure.

[0021] FIG. 10 illustrates a flowchart for QTP operation of a wireless LAN system related to the present disclosure.

[0022] Figure 11 is a drawing for explaining an IDC related to the present disclosure.

[0023] FIG. 12 illustrates a flowchart for IDC quiet operation according to one embodiment of the present disclosure.

[0024] FIG. 13 illustrates an example of a frame format for IDC quiet operation according to one embodiment of the present disclosure.

[0025] FIG. 14a illustrates another example of a frame format for IDC quiet operation according to one embodiment of the present disclosure.

[0026] FIG. 14b illustrates an example of a field format for IDC quiet operation according to one embodiment of the present disclosure.

[0027] FIG. 14c illustrates an example of an element for IDC quiet operation according to one embodiment of the present disclosure.

[0028] FIG. 14d illustrates another example of an element for IDC quiet operation according to one embodiment of the present disclosure.

[0029] FIG. 14e illustrates another example of an element for IDC quiet operation according to one embodiment of the present disclosure.

[0030] FIG. 15a illustrates an example of a frame format for IDC quiet operation according to one embodiment of the present disclosure.

[0031] FIG. 15b illustrates another example of a field format for IDC quiet operation according to one embodiment of the present disclosure.

[0032] FIG. 15c illustrates another example of a field format for IDC quiet operation according to one embodiment of the present disclosure.

[0033] FIG. 16a illustrates another example of a field format for IDC quiet operation according to one embodiment of the present disclosure.

[0034] FIG. 16b illustrates another example of a field format for IDC quiet operation according to one embodiment of the present disclosure.

[0035] FIG. 17 illustrates another example of elements and formats for IDC quiet operation according to one embodiment of the present disclosure.

[0036] FIG. 18 illustrates another example of a field format for IDC quiet operation according to one embodiment of the present disclosure.

[0037] FIG. 19 illustrates another example of a field format for IDC quiet operation according to one embodiment of the present disclosure.

[0038] FIG. 20 illustrates another example of a field format for IDC quiet operation according to one embodiment of the present disclosure.

[0039] FIG. 21 illustrates a flowchart of operations for IDC quiet operation of a device according to one embodiment of the present disclosure.

[0040] FIG. 22 illustrates a flowchart of operations for IDC quiet operation of a device according to one embodiment of the present disclosure.

[0041] FIG. 23 illustrates a flowchart of operations for IDC quiet operation of a device according to one embodiment of the present disclosure.

[0042] FIG. 24 illustrates a flowchart of operations for IDC quiet operation of a device according to one embodiment of the present disclosure.

[0043] FIG. 25 illustrates a flowchart of operations for IDC quiet operation of a device according to one embodiment of the present disclosure.

[0044] FIG. 26 illustrates a flowchart of operations for IDC quiet operation of a device according to one embodiment of the present disclosure.

[0045] FIG. 27 illustrates another example of a frame format for IDC quiet operation according to one embodiment of the present disclosure.

[0046] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the attached drawings. It should be noted that, where possible, identical components are represented by identical reference numerals throughout the attached drawings. Furthermore, detailed descriptions of well-known functions and configurations that may obscure the gist of the present disclosure will be omitted.

[0047] In describing the embodiments in this specification, descriptions of technical details that are well known in the technical field to which the present disclosure pertains and are not directly related to the present disclosure will be omitted. This is to avoid obscuring the gist of the present disclosure by omitting unnecessary explanations and to convey the gist more clearly.

[0048] For the same reason, some components in the attached drawings are exaggerated, omitted, or schematically depicted. Furthermore, the dimensions of each component do not entirely reflect its actual size.

[0049] The advantages and features of the present disclosure, and methods for achieving them, will become clearer with reference to the embodiments described below in detail with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below and may be implemented in various different forms. These embodiments are provided solely to ensure that the disclosure is complete and to fully inform those skilled in the art of the scope of the disclosure, and the present disclosure is defined solely by the scope of the claims.

[0050] At this time, it will be understood that each block of the flowchart drawings and combinations of the flowchart drawings can be performed by computer program instructions. These computer program instructions can be installed in a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing equipment, so that the instructions executed by the processor of the computer or other programmable data processing equipment create a means for performing the functions described in the flowchart block(s). These computer program instructions can also be stored in a computer-available or computer-readable memory that can direct a computer or other programmable data processing equipment to implement the functions in a specific manner, so that the instructions stored in the computer-available or computer-readable memory can also produce a manufactured item that includes an instruction means for performing the functions described in the flowchart block(s). Since the computer program instructions may be installed on a computer or other programmable data processing device, a series of operational steps may be performed on the computer or other programmable data processing device to create a computer-executable process, and the instructions that cause the computer or other programmable data processing device to perform the steps for performing the functions described in the flowchart block(s) may also provide steps for performing the functions described in the flowchart block(s).

[0051] Additionally, each block may represent a module, segment, or portion of code that contains one or more executable instructions for performing a specific logical function(s). It should also be noted that in some alternative implementation examples, the functions described in the blocks may occur out of order. For example, two blocks depicted in succession may actually be executed substantially concurrently, or the blocks may sometimes be executed in reverse order, depending on their respective functions.

[0052] Here, the term '~ unit' used in the present embodiment means a software or hardware component such as an FPGA or ASIC, and the '~ unit' performs certain roles. However, the '~ unit' is not limited to software or hardware. The '~ unit' may be configured to be on an addressable storage medium and may be configured to play one or more processors. Accordingly, as an example, the '~ unit' includes components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functions provided within the components and '~ units' may be combined into a smaller number of components and '~ units' or further separated into additional components and '~ units'. Additionally, components and '~parts' may be implemented to regenerate one or more CPUs within a device or secure multimedia card.

[0053] 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.

[0054] In this disclosure, terms such as "first," "second," etc. are used only to distinguish one component from another, are not used to limit the components, and do not limit the order or importance of 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.

[0055] 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.

[0056] 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 system 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 system based on the newly discussed IEEE 802.11bn (or UHR (ultra high reliability)) standards. Furthermore, the examples of the present disclosure can be applied to a next-generation wireless LAN system based on a new standards document that improves upon the IEEE 802.11bn.

[0057] Additionally, examples of the present disclosure may be applied to cellular wireless communication systems. For example, examples of the present disclosure may be applied to cellular wireless communication systems based on Long Term Evolution (LTE), LTE-Advanced (LTE-A), and New Radio (NR) technologies based on 3rd Generation Partnership Project (3GPP) standard documents.

[0058] FIG. 1 illustrates a configuration of a device for wireless communication according to one embodiment of the present disclosure.

[0059] The first device (100) and the second device (200) of FIG. 1 may be replaced with various terms such as terminal, wireless device, WTRU (Wireless Transmit and Receive Unit), UE (User Equipment), MS (Mobile Station), UT (user terminal), MSS (Mobile Subscriber Station), MSS (Mobile Subscriber Unit), SS (Subscriber Station), AMS (Advanced Mobile Station), WT (Wireless terminal), client terminal, or simply user.

[0060] In addition, the first device (100) and the second device (200) may be replaced with various terms such as access point (AP), base station (BS), fixed station, Node B, base transceiver system (BTS), network, artificial intelligence (AI) system, road side unit (RSU), repeater, router, relay, gateway, etc.

[0061] 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.

[0062] Referring to FIG. 1, the first device (100) and the second device (200) can transmit and / or receive wireless signals through various wireless LAN technologies (e.g., technologies based on the IEEE 802.11 standard document). The first device (100) and the second device (200) can include interfaces for a medium access control (MAC) layer and a physical (PHY) layer that follow the regulations of the IEEE 802.11 standard document.

[0063] In addition, the first device (100) and the second device (200) may additionally support various wireless communication technologies other than wireless LAN technology (for example, technologies based on 3GPP LTE, LTE-A, or NR standard documents). In addition, the devices of the present disclosure may be implemented as various devices such as mobile phones, vehicles, personal computers, AR (Augmented Reality) equipment, VR (Virtual Reality) equipment, 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).

[0064] A first device (100) includes one or more processors (102) and one or more memories (104), and may further include one or more transceivers (or 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 and / or a first signal, and then transmit a wireless signal including the first information and / or the first signal via the transceivers (106). In addition, the processor (102) may receive a wireless signal including second information and / or a second signal through the transceiver (106), and then store information obtained through signal processing of the second information and / or the second signal in the memory (104). The memory (104) may be connected to the processor (102) and may store various information related to the operation of the processor (102). For example, the memory (104) may 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., a technology based on the IEEE 802.11 document). A 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.

[0065] The second device (200) includes one or more processors (202) and one or more memories (204), and may further include one or more transceivers (or transceiver units) (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 memories (204) to generate third information and / or a third signal, and then transmit a wireless signal including the third information and / or the third signal via the transceivers (206). In addition, the processor (202) may receive a wireless signal including the fourth information and / or the fourth signal through the transceiver (206), and then store information obtained through signal processing of the fourth information and / or the fourth signal in the memory (204). The memory (204) may be connected to the processor (202) and may store various information related to the operation of the processor (202). For example, the memory (204) may perform some or all of the processes controlled by the processor (202), or 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., a technology based on the IEEE 802.11 document). A 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.

[0066] Hereinafter, hardware elements of the device (100, 200) will be described in more detail. Although not limited to the following, operations of 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 operations of 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 operation 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 operation 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, traffic or information according to the functions, procedures, proposals and / or methods disclosed in this 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, traffic or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed in this disclosure.

[0067] 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 read only memory (ROM), random access memory (RAM), erasable programmable ROM (EPROM), electronically EPROM (EEPROM), 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.

[0068] One or more transceivers (106, 206) can transmit user data, control information, data, traffic, wireless signals, and / or channels, etc., as described 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, data, traffic, wireless signals, and / or channels, etc., as described 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, traffic, wireless signals, and / or channels, etc., 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, traffic, wireless signals, and / or channels 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, traffic, wireless signals, and / or channels, etc., as described 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 (108, 208) may be multiple physical antennas or multiple logical antennas (e.g., antenna ports).One or more transceivers (106, 206) may 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 processed user data, control information, wireless signals / channels, etc. from baseband signals to RF band signals using one or more processors (102, 202). For this purpose, one or more transceivers (106, 206) may include an (analog) oscillator and / or a filter.

[0069] In one example, one of the devices (100, 200) may perform the intended operation of an AP, and the other of the devices (100, 200) may perform the intended operation of a non-AP STA. In another example, the transceiver (106, 206) of FIG. 1 may perform transmission and / or 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.).

[0070] Additionally, in the present disclosure, the operations of various STAs generating transmission / reception signals or performing data processing or calculations in advance for transmission / reception signals can be performed in the processor (102, 202) of FIG. 1. For example, an example of an operation of generating a transmission / reception signal or performing data processing or operation in advance for a transmission / reception signal is an operation of determining / obtaining / configuring / computing / decoding / encoding bit information of a field included in a PPDU (e.g., SIG (signal), STF (short training field), LTF (long training field), Data, etc.), 2) determining / configuring / obtaining time resources or frequency resources (e.g., subcarrier resources) used for a field included in a PPDU (e.g., SIG, STF, LTF, Data, etc.), 3) determining / configuring / obtaining a specific sequence (e.g., pilot sequence, STF / LTF sequence, extra sequence applied to SIG) used for a field included in a PPDU (e.g., SIG, STF, LTF, Data, etc.), 4) power control operation and / or power saving operation applied to an STA, 5) ACK (acknowledgement) signal It may include operations related to decision / acquisition / configuration / computation / decoding / encoding, etc. In addition, in the example below, various information (e.g., information related to fields / subfields / control fields / parameters / power, etc.) used by various STAs for decision / acquisition / configuration / computation / decoding / encoding of transmission / reception signals may be stored in the memory (104, 204) of FIG. 1.

[0071] 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.

[0072] An exemplary structure of a wireless LAN system related to the present disclosure is illustrated.

[0073] A wireless LAN system may have a structure composed of multiple components. The wireless LAN system can support transparent STA mobility to the upper layer through the interaction of the multiple components. 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 (BSS 1 and BSS 2), and the inclusion of two STAs as members of each BSS (STA 1 and STA 2 are included in BSS 1, and STA 3 and STA 4 are included in BSS 2). 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 the BSA, it cannot directly communicate with other STAs within the BSA.

[0074] If we do not consider the distributed system (DS) illustrated in Fig. 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, BSS 1 consisting of only STA 1 and STA 2, or BSS 2 consisting of only STA 3 and STA 4, can be representative examples of an IBSS, respectively. Such a configuration is possible when the STAs can communicate directly without an AP. Furthermore, this type of WLAN is not planned in advance but can be configured when a local area network (LAN) is required, and can also 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 the DS is not permitted, forming a self-contained network.

[0075] 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).

[0076] In a wireless LAN, the direct STA-to-STA distance may 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 DS can be configured.

[0077] 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 the distributed system medium (DSM, DS medium). 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.

[0078] 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).

[0079] An AP enables non-AP STAs associated with it to access the DS through the WM. An AP may refer to an entity that also has the functionality of an STA, and data movement between the BSS and the DS may be performed through the AP. For example, STA 2 and STA 3 illustrated in FIG. 2 have the functionality of an STA and provide the function of allowing associated non-AP STAs (STA 1 and STA 4) 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 the WM and the address used by an AP for communication on the DSM do not necessarily have to be the same. A BSS consisting of an AP and one or more STAs may be referred to as an infrastructure BSS.

[0080] Data transmitted from one of the STA(s) associated with an AP to the STA address of that AP is always received on an uncontrolled port and can be processed by an IEEE 802.1X port access entity. In addition, if the controlled port is authenticated, the transmitted data (or frame) can be forwarded to the DS.

[0081] In addition to the structure of the DS described above, an extended service set (ESS) may be established to provide wider coverage.

[0082] An ESS is a network of arbitrary size and complexity, and 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 LLC (Logical Link Control) layer. STAs included in an ESS can communicate with each other, and mobile STAs can move from one BSS to another (i.e., within the same ESS) transparently to the LLC. APs included in an ESS may have the same SSID (service set identifier). The SSID is distinct from the BSS ID (BSS SSID), which is the identifier of the BSS.

[0083] 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 in the same space as one (or more) ESS networks. This can occur in cases where an ad-hoc network operates in 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.

[0084] Figure 3 illustrates a link setup process related to the present disclosure.

[0085] For an STA to set up a link and transmit and receive data on a network, it must discover the network via an AP, perform authentication, establish an association, and establish security. 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.

[0086] At step 310, 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.

[0087] Scanning methods include active scanning and passive scanning. Figure 3 illustrates a network discovery operation that includes 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.

[0088] 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.

[0089] After the STA discovers the network, an authentication process may be performed at step 320. This authentication process may be referred to as the first authentication process to clearly distinguish it from the security setup operation of step 340 described below.

[0090] 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 request frame and the authorization response frame used in the authentication process belong to management frames.

[0091] 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.

[0092] An STA can transmit 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.

[0093] After the STA is successfully authenticated, an association process may be performed at step 330. 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.

[0094] The association request frame may include information about various capabilities, a beacon listen interval, a service set identifier (SSID), supported rates, supported channels, a robust security network (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 the combined request / response frame may further include additional information.

[0095] After the STA successfully joins the network via the AP, a security setup process may be performed at step 340. The security setup process of step 340 may include an authentication process via a Robust Security Network Association (RSNA) request / response. Furthermore, if the authentication process of step 320 is referred to as the first authentication process, the security setup process of step 340 may also be referred to simply as the authentication process.

[0096] The security setup process of step 340 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.

[0097] Figure 4 illustrates a backoff operation related to the present disclosure.

[0098] In wireless LAN systems, the basic MAC access mechanism is Carrier Sense Multiple Access with Collision Avoidance (CSMA / CA). CSMA / CA, 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 performs Clear Channel Assessment (CCA) to sense the wireless channel or medium for a predetermined time period (e.g., DIFS (DCF Inter-Frame Space)) before starting transmission. If the sensing result determines that the medium is in an idle state, the AP and / or STA starts 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 predetermined delay period (e.g., a random backoff period) for medium access before attempting to transmit frames. By applying the random backoff period, multiple STAs may attempt to transmit frames after waiting for different periods of time, thereby minimizing collisions.

[0099] Additionally, the IEEE 802.11 MAC protocol provides a Hybrid Coordination Function (HCF). HCF is based on the DCF and Point Coordination Function (PCF). PCF is a polling-based synchronous access method, which refers to a method in which all receiving APs and / or STAs periodically poll to ensure that they can receive data frames. HCF also includes Enhanced Distributed Channel Access (EDCA) and HCF Controlled Channel Access (HCCA). EDCA is a contention-based access method in which a provider provides data frames to multiple users, while HCCA uses a non-contention-based channel access method using a polling mechanism. In addition, HCF includes a medium access mechanism to improve the Quality of Service (QoS) of a wireless LAN, and can transmit QoS data in both a Contention Period (CP) and a Contention Free Period (CFP).

[0100] Referring to Fig. 4, an operation based on a random backoff period is described. When an occupied / busy medium changes to an idle state, multiple STAs may attempt to transmit data (or frames). To minimize collisions, each STA may 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 may 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 initially given a value of CWmin, but in case of a transmission failure (e.g., if an ACK for a transmitted frame is not received), the STA may increase the CW by a factor of two. When the CW parameter value reaches CWmax, the STA may attempt data transmission while maintaining the CWmax value until the data transmission is successful, and if the data transmission is successful, the CW is reset to the CWmin value. The values ​​of CW, CWmin and CWmax can be set to 2n-1 (n=0, 1, 2, ...).

[0101] 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.

[0102] In the example of FIG. 4, when a packet to be transmitted reaches the MAC of STA3, STA3 can immediately transmit the 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 the random backoff count value it has selected after waiting for DIFS if it confirms that the medium is 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 was stopped. That is, STA1 and STA5 can start frame transmission 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 frame transmission. While STA2 occupies the medium, STA4 may also have data to transmit. When the medium becomes idle, STA4 waits for DIFS, counts down according to a random backoff count value selected by it, and then starts frame transmission. In the example of FIG. 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.

[0103] As shown in the example of Fig. 4, a data frame is a frame used for transmitting data to an upper 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 without being transmitted to an upper layer, and is transmitted after a backoff performed after an IFS such as DIFS or PIFS (Point coordination function IFS) elapses. A management frame may include a beacon, an association request / response, a re-association request / response, a probe request / response, an authentication request / response, etc. as a subtype frame. A control frame is a frame used to control access to the medium. Control frames can include RTS (Request-To-Send), CTS (Clear-To-Send), ACK (Acknowledgment), PS-Poll (Power Save-Poll), Block ACK (B-ACK or BlockAck), Block ACK Request (BlockACKReq), NDP announcement (null data packet announcement), Trigger, etc. as subtype frames. 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) has elapsed. The type and subtype of a frame can be identified by the type field and subtype field in the frame control (FC) field.

[0104] 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.

[0105] FIG. 5 illustrates a frame transmission operation based on CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) in connection with the present disclosure.

[0106] 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 that receives 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.

[0107] In the example of FIG. 5, STA1 wants to transmit data to STA2, and STA3 is in a position to overhear part or all of the frames transmitted and received between STA1 and STA2.

[0108] 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. 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. 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.

[0109] 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 the NAV timer.

[0110] 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.

[0111] 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.

[0112] 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.

[0113] FIG. 6 illustrates an exemplary format of a frame used in a wireless LAN system related to the present disclosure.

[0114] Based on an instruction or primitive (meaning a set of instructions or parameters) from the MAC layer, the PHY layer can prepare an MPDU (MAC PDU) to be transmitted. When the PHY layer receives a command requesting the start of transmission 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 can monitor the header of the preamble and send a command to the MAC layer notifying the start of reception by the PHY layer.

[0115] 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) frame format is defined.

[0116] A basic PPDU frame may include a short training field (STF), a long training field (LTF), a SIGNAL (SIG) field, and a data field. The most basic (e.g., non-HT (high throughput)) PPDU frame format may consist of only L-STF (Legacy-STF), L-LTF (Legacy-LTF), a SIG field, and a data field. In addition, depending on the type of PPDU frame format (e.g., HT-mixed format PPDU, HT-greenfield format PPDU, VHT (very high throughput) PPDU, etc.), additional (or different types of) STF, LTF, and SIG fields may be included between the SIG field and the data field. Specific types of frame formats are described later in FIG. 7.

[0117] STF is a signal for signal detection, AGC (automatic gain control), diversity selection, precise time synchronization, etc., and LTF is a signal for channel estimation, frequency error estimation, etc. STF and LTF are signals for synchronization and channel estimation of the OFDM (orthogonal frequency division multiplexing) physical layer.

[0118] The SIG field may include a RATE field and a LENGTH field, among others. The RATE field may include information about the modulation and coding rate of the data. The LENGTH field may include information about the length of the data. Additionally, the SIG field may include a parity bit, a SIG TAIL bit, among others.

[0119] 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.

[0120] 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 frame format.

[0121] The MAC header includes a frame control field, a duration / ID field, an address field, etc. The frame control field may include control information necessary for frame transmission / reception. The duration / ID field may be set to the time for transmitting the corresponding frame, etc. The specific contents of the Sequence Control, QoS Control, and HT Control subfields of the MAC header are omitted.

[0122] Although not shown in FIG. 6, the null data packet (NDP) frame format refers to a frame format that does not include a data packet. That is, the NDP frame refers to a frame format that includes the PLCP (physical layer convergence procedure) header portion (i.e., STF, LTF, and SIG fields) of the general PPDU frame format, but does not include the remaining portion (i.e., data field). The NDP frame may also be referred to as a short frame format.

[0123] FIG. 7 illustrates an exemplary format of a physical layer protocol data unit (PPDU) of a wireless LAN system related to the present disclosure.

[0124] Standards such as IEEE 802.11a / g / n / ac / ax / be use various PPDU formats. The basic PPDU format (IEEE 802.11a / g format) 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.

[0125] The HT PPDU format (IEEE 802.11n format) 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 may be referred to as an HT-mixed format. Although not illustrated, an HT-greenfield format PPDU may be defined, which corresponds to a format that does not include L-STF, L-LTF, and L-SIG, and is composed of HT-GF-STF, HT-LTF1, HT-SIG, one or more HT-LTF, and Data fields.

[0126] The VHT PPDU format (IEEE 802.11ac format) includes VHT SIG-A, VHT-STF, VHT-LTF, and VHT-SIG-B fields in addition to the basic PPDU format.

[0127] The HE PPDU format (IEEE 802.11ax format) 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. 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 PPDU format for single-users (SUs) does not include the HE-SIG-B. 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 μs. 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 up to 16 μs.

[0128] FIG. 8 illustrates another exemplary format of a PPDU of a wireless LAN system related to the present disclosure.

[0129] The EHT PPDU format (IEEE 802.11be format) of FIG. 8 may include an EHT MU PPDU format and an EHT TB PPDU format. The EHT MU PPDU format corresponds to a PPDU that carries one or more data (or PSDU) for one or more users. The EHT MU PPDU can be used for both SU transmission and MU transmission, and the EHT MU PPDU may correspond to a PPDU for one receiving STA or multiple receiving STAs. The EHT TB PPDU omits the EHT-SIG compared to the EHT MU PPDU. An STA that receives a trigger for UL MU transmission (e.g., a trigger frame or an RTS frame) can perform UL transmission based on the EHT TB PPDU format.

[0130] The EHT PPDU format includes RL-SIG, U-SIG (Universal SIG), EHT-SIG, EHT-STF, EHT-LTF(s), and PE fields in addition to the basic PPDU format. Depending on the specific examples of the EHT PPDU format, some fields may be excluded or their lengths may vary. For example, depending on the EHT MU PPDU format and EHT TB PPDU format described above, some fields of the EHT PPDU format may or may not be included, or the lengths of specific fields may vary.

[0131] FIG. 9 illustrates the QTP (quiet time period) operation of a wireless LAN system related to the present disclosure.

[0132] QTP refers to a time period during which a non-AP STA wishing to transmit a P2P packet requests the AP to suspend communication with other non-AP STAs in the BSS to which it belongs, for P2P (peer-to-peer) communication between devices (e.g., between non-AP STAs). QTP operation may include a request process, a response process, and a setup process for this QTP period.

[0133] Taking FIG. 9 as an example, STA1 is a non-AP STA that requests QTP from the AP, and transmits a QTP request frame to the AP for P2P communication with STA3. The AP that receives the QTP request frame confirms the QTP request, then decides to set QTP to prevent other non-AP STAs in the BSS from transmitting packets, and transmits a QTP response frame containing information related to this decision to STA1. The QTP response frame may include information (or elements) such as QTP duration, QTP offset, QTP period, repetition count, SSID, etc. that prevent other non-AP STAs from transmitting data.

[0134] Next, the AP that transmitted the QTP response frame can transmit the QTP setup frame to the non-AP STAs within the BSS before starting the QTP according to the QTP response frame. The QTP setup frame is to establish the QTP, which is a time period during which non-AP STAs other than STA1, the non-AP STA that requested the QTP, cannot transmit packets. During the duration included in the QTP setup frame, STAs other than STA1 are restricted from accessing the channel, such as transmitting packets.

[0135] STA1, which requested QTP, transmits a P2P frame to STA3 within QTP. STA3, which receives the P2P frame, can transmit a block acknowledgement (BlockAck, BA) frame to STA1 within QTP.

[0136] After receiving the QTP setup frame, STA2 can know that P2P traffic is transmitted by another STA within the QTP. Even if STA2 has packets to transmit in the QTP, it may not attempt to access the channel or may not operate the backoff counter. Meanwhile, QTP is not a mandatory operation for non-APs that have received the QTP setup frame. Therefore, even if STA2 receives the QTP setup frame, it may ignore QTP and operate. For example, STA2 may attempt to access the channel while continuously operating the backoff counter. In this case, STA2 may compete for channel access with the P2P frames between STA1 and STA3 within the QTP.

[0137] Meanwhile, STA4 may be a legacy STA that cannot perform QTP operations, for example. In this case, even if STA4 receives a QTP setup frame, it cannot interpret the QTP setup frame, so STA4 can continue to access the channel even within QTP.

[0138] FIG. 10 illustrates a flowchart for QTP operation of a wireless LAN system related to the present disclosure.

[0139] In Fig. 10, the requesting STA may include a non-AP STA, i.e., STA1, that transmitted the QTP request frame in Fig. 9, and the responding AP may include an AP that received the QTP request frame in Fig. 9. The requesting STA may include an SME (station management entity) entity and a MAC entity within it, and the responding AP may also include an SME entity and a MAC entity.

[0140] In FIG. 10, the requesting STA SME can send an MLME (MAC layer management entity)-QTP.request primitive to the requesting STA MAC, and based on this, the requesting STA MAC can send the QTP request frame described in FIG. 9 to the responding AP MAC. The responding AP MAC can send an MLME-QTP.indication primitive to the responding AP SME, and in response, the responding AP SME can send an MLME-QTP.response primitive to the responding AP MAC. The responding AP MAC can send the QTP response frame described in FIG. 9 to the requesting STA MAC, and based on this, the requesting STA MAC can send an MLME-QTP.confirm primitive to the requesting STA SME. Thereafter, prior to starting QTP, the responding AP MAC can send a QTP setup frame to the requesting STA MAC.

[0141] Figure 11 is a drawing for explaining an IDC related to the present disclosure.

[0142] As devices evolve, they (including non-AP STAs and APs) support a variety of different radio access technologies (RATs). Furthermore, as devices become increasingly smaller, antennas and transceivers supporting multiple RATs are mounted adjacent to each other within the device. Alternatively, a single radio frequency (RF) chain within the device may be shared among different RATs. In particular, when different RATs occupy adjacent frequency bands, there is a growing need for seamless coexistence (i.e., in-device coexistence, or IDC) among different RATs within the device. This IDC must be considered across various RATs, such as wireless LAN (WLAN), Bluetooth (BT), Bluetooth low-energy (BLE), peer-to-peer (P2P), ultra-wideband (UWB), licensed assisted access (LAA), and NR unlicensed (NR-U).

[0143] Recently, various discussions have been held to improve or resolve these IDCs. Examples include methods that support transmission and reception of wireless access technologies other than WLAN systems by utilizing schedulable time intervals such as TWT (target wakeup time), APSU (automatic power save delivery), and U-APSD (unscheduled APSD), and methods that support transmission and reception of other wireless access technologies by utilizing unscheduled time intervals such as AM (active mode) / PS (power saving) mode transition or flexible TWT. These methods correspond to methods that utilize available or unavailable time.

[0144] Alternatively, as illustrated in Fig. 11, a method of indicating target availability or target unavailability within a specific control frame, such as an initial control frame (ICF), an initial control response (ICR), or a response control frame (RCF), is also being discussed. According to this method, by indicating the unavailability (or availability) of an IDC target wireless access technology (i.e., a wireless access technology other than a wireless LAN system) during the transmission and reception of a control frame, a device can operate or not operate at a specific point in time after transmitting and receiving a data frame.

[0145] However, the various methods for improving IDC described above fall short in precisely and efficiently controlling it. Specifically, the 802.11bn standard document discusses various methods for improving reliability. Therefore, from this perspective, a method for controlling IDC through specific yet simple procedures is needed. Furthermore, various discussions are underway to control IDC when supporting the multi-link device (MLD) function based on the 802.11be standard.

[0146] Below, we propose a method for improving IDC based on the QTP operations and procedures described in Figures 9 and 10. As previously explained, QTP operations have the characteristic that operations based on a request from a specific STA affect all other terminals within the BSS. Therefore, we specifically describe embodiments for performing IDC-conscious operations or controlling IDC on a device-by-device basis by utilizing the aforementioned characteristics.

[0147] FIG. 12 illustrates a flowchart for IDC quiet operation according to one embodiment of the present disclosure.

[0148] Hereinafter, IDC quiet operation may mean an operation in which a non-AP STA suspends or restricts its own wireless LAN operation for a predetermined time period in order to operate a wireless access technology other than WLAN. The other wireless access technology may include Bluetooth, BLE, UWB, LAA, NR-U, or P2P link other than WLAN, and may also include other technologies that utilize wireless resources or wireless channels in addition to the described wireless access technology. According to one embodiment, the IDC quiet operation may include a feature that can execute one or more actions within a specified periodic or instantaneous time (i.e., quiet period), and examples of the actions are described in detail below.

[0149] Hereinafter, a predetermined time period during which the IDC quiet operation is applied may be referred to as a quiet period, and this quiet period may be a periodic period or include instantaneous frames. During the quiet period, non-AP STAs' wireless LAN scheduling may not be performed to allow other wireless access technologies to operate, and limited transmission and reception may be performed for non-AP STAs. For example, during the quiet period, traffic may be transmitted and received with a reduced bandwidth for the wireless LAN to avoid interference with other wireless access technologies, and when sharing an RF (radio frequency) chain with other wireless access technologies, traffic may be transmitted and received through a reduced number of spatial streams (NSS), or only transmission or reception of the wireless LAN may be performed.

[0150] A non-AP STA can request that the AP suspend or limit its wireless LAN operations for IDC quiet operation. A non-AP STA that sends such a request is referred to as an IDC quiet requesting STA. An AP that receives a request from a non-AP STA and, accordingly, supports the non-AP STA's IDC quiet operation is referred to as an IDC quiet responding AP.

[0151] According to one embodiment, specific frames exchanged within a quiet period according to an IDC quiet operation may be identified by a service specific identifier. In addition, an IDC quiet responding AP may trigger NAV configuration of surrounding STAs at a specific time interval using an action frame, such as an IDC quiet operation notification frame described below. According to another embodiment, an IDC quiet responding AP may trigger NAV configuration of surrounding STAs at a specific time interval using a control frame, such as a CTS-to-self, instead of an action frame, which may be intended to restrict operations within the quiet period for legacy STAs that cannot receive or interpret the IDC quiet notification frame.

[0152] To explain in detail with the example shown in Fig. 12, the IDC quiet requesting STA transmits an IDC quiet request to the IDC quiet responding AP (1210). In response, the IDC quiet responding AP transmits an IDC quiet response to the IDC quiet requesting STA (1220). The IDC quiet responding AP may transmit an IDC quiet operation notification to non-AP STAs other than the IDC requesting STA for NAV configuration during the quiet period (1230). Although not shown, the IDC quiet responding AP may also transmit a control frame such as a CTS-to-self frame instead of a quiet notification frame.

[0153] According to one embodiment, the IDC quiet request transmitted by an IDC quiet requesting STA to an IDC quiet responding AP may mean a frame that explicitly or implicitly indicates the meaning of the IDC quiet request, and such a frame may be a management frame, an action frame, or a control frame. Alternatively, the IDC quiet request transmitted by an IDC quiet responding STA to an IDC quiet responding AP may mean a frame including an element for the IDC quiet request, and may mean a MAC header including an element for the IDC quiet request. For the convenience of explanation below, a transmission object according to at least one of the various forms described above may be referred to as an IDC quiet operation request frame.

[0154] According to one embodiment, the IDC quiet response transmitted by the IDC quiet responding AP to the IDC quiet requesting STA may mean a frame that explicitly or implicitly indicates the meaning of the IDC quiet response, and such a frame may be a management frame, an action frame, or a control frame. Alternatively, the IDC quiet response transmitted by the IDC quiet responding AP to the IDC quiet requesting STA may mean a frame including an element for the IDC quiet response, and may mean a MAC header including an element for the IDC quiet response. For the convenience of explanation below, a transmission object according to at least one of the various forms described above may be referred to as an IDC quiet operation response frame.

[0155] According to one embodiment, the IDC quiet notification transmitted by the IDC quiet responding AP to the IDC quiet requesting STA may mean a frame that explicitly or implicitly indicates the meaning of the IDC quiet notification, and such a frame may be a management frame, an action frame, or a control frame. Alternatively, the IDC quiet notification transmitted by the IDC quiet responding AP to the IDC quiet requesting STA may mean a frame including an element for the IDC quiet notification, and may mean a MAC header including an element for the IDC quiet notification. For the convenience of explanation below, a transmission object according to at least one of the various forms described above may be referred to as an IDC quiet operation notification frame.

[0156] In one embodiment, an IDC quiet requesting STA may immediately suspend or break a specific quiet period by transmitting a PS-poll frame or a QoS null frame upon receiving an IDC quiet response frame and determining that a quiet period is not necessary. In addition, the IDC quiet requesting STA may perform a suspend or resume of an action frame to control an IDC quiet operation in a predetermined time interval including two or more continuous quiet periods.

[0157] Meanwhile, in FIG. 12, each of the frames for the IDC quiet request transmitted from the IDC quiet requesting STA to the IDC quiet responding AP, the frames for the IDC quiet response transmitted from the IDC quiet responding AP to the IDC quiet requesting STA, and the frames for the IDC quiet notification transmitted from the IDC quiet responding AP to the IDC quiet requesting STA may be a predetermined action frame or a control frame.

[0158] In this way, the frame for the IDC quiet request, the frame for the IDC quiet response, and the frame for the IDC quiet notification may be an extended frame of an existing action frame and / or a control frame. Alternatively, the frame for the IDC quiet request, the frame for the IDC quiet response, and the frame for the IDC quiet notification may be a frame that adds a new field for the IDC quiet operation to the existing action frame and / or control frame. According to one embodiment, the frame for the IDC quiet request, the frame for the IDC quiet response, and the frame for the IDC quiet notification may mean an action frame and / or a control frame that further includes one or more fields of an element for the IDC quiet operation proposed in the present disclosure below. Specific embodiments for elements or fields added for the frame for the IDC quiet request, the frame for the IDC quiet response, and the frame for the IDC quiet notification are described below with reference to FIGS. 14a to 14e.

[0159] FIG. 13 illustrates an example of a frame format for IDC quiet operation according to one embodiment of the present disclosure.

[0160] Below, the frame format for IDC quiet operation is described. According to one embodiment, one of the UHR action fields can be assigned for IDC quiet operation. Fig. 13(a) illustrates the structure of the IDC quiet operation frame body, and Fig. 13(b) illustrates the structure of the UHR or protected UHR action field of order 2 in the IDC quiet operation frame body.

[0161] In the embodiment of Fig. 13(a), the value of the category field may be 40 for UHR or 41 for protected UHR, but these values ​​are merely examples and are not limited thereto. In the embodiment of Fig. 13(b), the UHR action field or protected UHR action may have a value of 0 to indicate the IDC quiet operation action field, but of course, it may have a value other than 0.

[0162] Meanwhile, the structure of the format illustrated in FIG. 13, the field names, the values ​​indicated by the fields, the number of fields to which meaningful values ​​are assigned, the order of the fields, the number of octets or bits, whether fields are included in the format, etc. are merely examples, and may of course be changed differently from the illustrated and described embodiment. Hereinafter, FIGS. 14a to 14e describe the IDC quiet operation element of order 3 of the IDC quiet operation frame body in FIG. 13(a).

[0163] Figures 14a and 14b illustrate further examples of frame formats for IDC quiet operation according to an embodiment of the present disclosure. The IDC quiet operation action frame may correspond to an Action No ACK frame among the UHR or protected UHR action fields. Figure 14a illustrates the structure of an IDC quiet operation element included in the IDC quiet operation action frame.

[0164] In FIG. 14a, the element ID field includes 1 octet and can have a value of 255, and the element ID extension field includes 1 octet and can have a value of any one of 136 to 255. In FIG. 14a, the IDC quiet operation element can include a control field of 1 octet, and this control field can indicate a value for specifying a subtype of the IDC quiet operation element. Specifically, with the example shown in FIG. 14b, the control field can include a value (e.g., 0) for indicating an IDC quiet operation request frame transmitted by an IDC quiet requesting STA, a value (e.g., 1) for indicating an IDC quiet operation response frame transmitted by an IDC quiet responding AP, or a value (e.g., 2) for indicating an IDC quiet operation notification frame transmitted by an IDC quiet responding AP, but these values ​​are merely examples and are not limited thereto. According to one embodiment, two or more least significant bits (LSBs) included in the above-described control field may indicate a subtype of an IDC quiet operation element, and these two or more LSBs may be referred to as an IDC quiet operation subtype field.

[0165] The IDC quiet content field illustrated in Fig. 14a is a field with a variable length and may include information related to the IDC quiet operation frame indicated by the value included in the control field described above. Specific details regarding the IDC quiet content field are described in detail with reference to Figs. 14c, 14d, and 14e.

[0166] FIG. 14C illustrates an example of an IDC quiet operation request element according to an embodiment of the present disclosure. Specifically, FIG. 14C illustrates an example of an IDC quiet content field of an IDC quiet operation element included in an IDC quiet operation request frame (i.e., a frame for an IDC quiet operation request). The fields included in the IDC quiet content field are described in detail below.

[0167] The dialog token field contains one octet and can identify a response subtype corresponding to a request subtype. The request mode field contains one octet and can indicate addition, removal, suspension, resumption, and reconfiguration of an IDC quiet operation. For example, a value of 0 in the request mode field can correspond to the addition of a subsequent quiet period, 1 to the removal of a subsequent quiet period, 2 to the suspension of a subsequent quiet period, 3 to the resumption of a subsequent quiet period, and 4 to the reconfiguration of a subsequent quiet period, respectively. When the value of the request mode field is any of 1-3, one or more of the subsequent fields may not be included in the content field or may have no meaning.

[0168] The radio mode field contains one octet and can define a transmit mode or a receive mode during the quiet period. For example, a value of 0 in the radio mode field can be used for unavailability, a value of 1 can be used for Tx only mode, a value of 2 can be used for Rx only mode, a value of 3 can be used for both Tx and Tx mode, and the remaining values ​​can be reserved. In addition, according to one embodiment, a value of 0xFF can be used to block not only the unavailability of the IDC quiet requesting STA but also all transmissions of other STAs within the same channel during the quiet period.

[0169] The Quiet Mode field contains 1 octet and may indicate the range of the IDC quiet operation. A value of 0 in the Quiet Mode field may correspond to that the IDC quiet operation applies only to the IDC quiet requesting STA, a value of 1 may correspond to that the AP requests to block transmissions from other associated STAs during the quiet period, and a value of 2 may correspond to that the AP requests to block transmissions from associated STAs of adjacent BSSs during the quiet period.

[0170] The period offset field may contain one or two octets. The period offset field may be set to the offset (expressed in time units (TU)) of the first quiet period from the target beacon transmission time (TBTT), or to the offset (expressed in TU) from the frame containing this element to the beginning of the first quiet period. In the latter case, the start position of the preamble of the PPDU containing this element may be the reference time.

[0171] The period duration field contains one octet and can be set to the duration of the quiet period. For example, the period interval field can be expressed in units of 32 μs.

[0172] The period interval field contains one or two octets and may be set to the requested interval between the start of two consecutive quiet periods, expressed in TUs.

[0173] The repetition count field contains 1 octet and can be set to the number of requested quiet periods. For example, if the value of the repetition count field is 0, it can indicate that the configured quiet period operates only once (one time operation). According to one embodiment, if the value of the repetition count field is 0xFF (i.e., 255) or another specific value, it can indicate that the configured quiet period is maintained continuously. In other words, it can mean that the configured quiet period is not repeated only a specific number of times, but is continuously repeated without ending (never ending).

[0174] The channel field contains one or two octets and can indicate which subchannels are available for use during the quiet period. For example, assuming the primary 20 MHz is set as the lowest channel number, 0x0003 (1 bit corresponds to a 20 MHz subchannel, so 2 octets for 320 MHz) could indicate that the possible subchannel set is known as the primary 40 MHz channel. Conversely, this field can also be used to indicate which subchannels are unavailable during the quiet period.

[0175] The number of spatial streams (NSS) field contains 1 octet and may indicate the maximum number of spatial streams that can be used during a quiet period.

[0176] The service specific identifier field contains one octet and may identify the type of heterogeneous technology (i.e., another radio access technology) or P2P connection that will be used during the quiet period.

[0177] FIG. 14d illustrates an example of an IDC quiet operation response element according to an embodiment of the present disclosure. Specifically, FIG. 14d illustrates an example of an IDC quiet content field of an IDC quiet operation element included in an IDC quiet operation response frame (i.e., a frame for an IDC quiet operation response). The fields included in the IDC quiet content field are described in detail below, but descriptions of fields that are identical to those in FIG. 14c are omitted.

[0178] The status code field contains 1 octet and can indicate the status value of the requested operation. For example, the status code field can indicate SUCCESS with a value of 0, REJECT with a value of 1, and COUNTER with a value of 2 to 8. When the status code field has a value of 2 to 8 to indicate COUNTER, a retry can be requested by changing at least one of the mode, offset, duration, interval, count, channel, and / or NSS of the quiet period, respectively. The values ​​9 to 255 of the status code field can be reserved values.

[0179] In one embodiment, when the status code field is set to mean COUNTER, the IDC quiet responding AP may suggest values ​​to the IDC quiet requesting STA by setting the values ​​of certain fields to recommended values. An IDC quiet requesting STA that receives an IDC quiet response element may recognize the suggestion of the IDC quiet responding AP, and the IDC quiet requesting STA may modify the values ​​of the previous request and transmit a new request.

[0180] FIG. 14E illustrates an example of an IDC quiet operation notification element according to an embodiment of the present disclosure. Specifically, FIG. 14E illustrates an example of an IDC quiet content field of an IDC quiet operation element included in an IDC quiet operation notification frame (i.e., a frame for an IDC quiet operation notification). The fields included in the IDC quiet content field are described in detail below, but descriptions of fields that are identical to those in FIG. 14C and FIG. 14D are omitted.

[0181] When a request by an IDC quiet requesting STA is accepted and transmission prohibition is required for surrounding STAs or one or more associated STAs, the IDC quiet responding AP may signal this request by transmitting a broadcast frame or unicast frame containing an IDC quiet operation notification element.

[0182] An IDC quiet responding AP may transmit an IDC quiet operation notification in advance of the arrival (or start) of the associated quiet period. Neighboring STAs that receive the IDC quiet operation notification element may stop decrementing their backoff counters or may not participate in contention by setting a NAV. Specifically, neighboring STAs that receive the IDC quiet operation notification element may stop decrementing their backoff counters or may not participate in contention by setting a NAV within the quiet period indicated by the IDC quiet operation notification.

[0183] Additionally, according to one embodiment, an IDC quiet requesting STA or an IDC quiet responding AP may initiate a transmission opportunity (TXOP) at the moment an approved quiet period is reached to trigger NAV configuration of nearby STAs.

[0184] Non-AP STAs that support IDC quiet operation by deciding to remain quiet during the quiet period may stop decrementing the backoff counter at the start of the quiet period and resume decrementing the backoff counter when the quiet period ends.

[0185] According to one embodiment, a mobile AP may broadcast an IDC quiet operation notification element including the fields illustrated in FIG. 14e by including it in a beacon frame or a probe response frame. That is, the mobile AP may broadcast the IDC quiet operation notification element without exchanging the IDC quiet operation request element or the IDC quiet operation response element described above. This is to indicate that the mobile AP cannot operate as an AP (i.e., is unavailable) during the quiet period due to reasons such as power consumption, heat generation, or mobility.

[0186] Although the above describes that the mobile AP is not operable (i.e., unavailable) during the quiet period, in another embodiment, the mobile AP may operate by limiting (or changing) some modes, operations, or functions during the quiet period. For example, the mobile AP may operate by limiting or changing at least one of the bandwidth, transmit / receive mode, or NSS during the quiet period, and for this purpose, the mobile AP may transmit an IDC quiet operation element indicating related information in a beacon frame or a probe response frame.

[0187] The structure of the format illustrated in FIGS. 14a to 14e, the field names, the values ​​indicated by the fields, the number of fields to which meaningful values ​​are assigned, the order of the fields, the number of octets or bits, whether fields are included in the format, etc. are merely examples and may, of course, be changed differently from the illustrated and described embodiment.

[0188] Meanwhile, based on the embodiments described in FIGS. 12 to 14e, the procedure of an IDC quiet requesting STA for IDC quiet operation and the procedure of an IDC quiet responding AP can be described as follows.

[0189] An IDC quiet requesting STA transmits an IDC quiet request frame, which is an action frame, and the control field of the IDC quiet operation element included in the IDC quiet request frame can indicate an IDC quiet operation request subtype. The IDC quiet request frame can include at least the duration, interval, and type fields among the information described above for the IDC quiet operation.

[0190] Meanwhile, the above described example in which an IDC quiet requesting STA transmits a single IDC quiet operation element, it is also possible for an IDC quiet requesting STA to transmit multiple IDC quiet operation elements. In this case, the IDC quiet requesting STA can generate an IDC quiet operation element for each of a plurality of quiet periods and transmit an IDC quiet request frame.

[0191] Next, the IDC quiet requesting STA receives an IDC quiet response frame, which is an action frame, and the control field of the IDC quiet operation element included in the IDC quiet response frame can indicate an IDC quiet operation response subtype. When the IDC quiet requesting STA receives an IDC quiet response frame in which the dialog token of the IDC quiet response frame matches the request token and the status code is set to a value indicating SUCCESS, the quiet operation requested by the IDC quiet requesting STA is confirmed.

[0192] An IDC quiet responding AP may receive an IDC quiet operation element of the IDC quiet operation request subtype from an IDC quiet requesting STA and transmit an IDC quiet response frame to the IDC quiet requesting STA in a unicast manner or in a broadcast manner.

[0193] If the status code of the IDC quiet response frame is SUCCESS, the AP approves the request. The AP schedules a quiet period based on the approved request. The transmitted IDC quiet response frame may include a copy of the dialogue token from the IDC quiet requesting STA. Additionally, if the number of quiet periods exceeds the value of the repetition count field, the IDC quiet operation procedure may be terminated.

[0194] If the status code of the IDC quiet response frame is REJECT, the AP indicates that the request cannot be fulfilled.

[0195] If the status code of the IDC quiet response frame is COUNTERED, the AP counters the request with the recommended values ​​and rejects the current request. Upon receiving this counter proposal, the IDC quiet requesting STA can send a new IDC quiet request frame to set up a new request.

[0196] An IDC quiet responding AP may schedule transmission of an IDC quiet operation notification frame at the start of a quiet period or prior to the quiet period. Alternatively, the IDC quiet responding AP may transmit a control frame (e.g., a CTS-to-self frame) at the start of a quiet period or prior to the quiet period. In one embodiment, the IDC quiet responding AP may transmit a control frame to restrict operations within the quiet period for legacy STAs that do not support the capability to receive or interpret IDC quiet notification frames.

[0197] FIGS. 15A, 15B, and 15C illustrate examples of frame formats for IDC quiet operation according to an embodiment of the present disclosure. FIGS. 15A, 15B, and 15C illustrate a new action frame format proposed for IDC quiet operation according to the embodiments described above.

[0198] According to one embodiment, an action frame for an IDC quiet operation may include the format illustrated in FIG. 15a. The format illustrated in FIG. 15a may be a format of a UHR or protected UHR action frame. Among the fields (or subfields) included in the format of the IDC quiet operation element illustrated in FIG. 15a, detailed descriptions of fields identical to those described above in FIGS. 14a to 14e will be omitted.

[0199] According to the embodiment illustrated in FIG. 15a, the format of the IDC quiet operation element may not include a field for a dialog token and a field for a status code. In such an embodiment, the field for a dialog token and a field for a status code may be included in the format of the IDC quiet operation request / response / notification frame action field instead of the format of the IDC quiet operation element. That is, as illustrated in (a) of FIG. 15b, the action field format of the IDC quiet request frame may include a field for a dialog token in the order of order 3 and a field for an IDC quiet operation element in the order of order 4. As illustrated in (b) of FIG. 15b, the action field format of the IDC quiet response frame may include a field for a dialog token in the order of order 3, a field for a status code in the order of order 4, and a field for an IDC quiet operation element in the order of order 5. As illustrated in (c) of FIG. 15c, the action field format of the IDC quiet notification frame may include a field for the IDC quiet operation element in the order of order 3.

[0200] According to this embodiment, at least three action fields (i.e., an IDC quiet operation request frame, an IDC quiet operation response frame, and an IDC quiet operation notification frame) may be allocated for an IDC quiet operation, and a field may be required to distinguish which action frame an IDC quiet operation element included in the action field format for the IDC quiet operation is for. Accordingly, as illustrated in FIG. 15c, a UHR or protected UHR action field may include a value for indicating any one of an IDC quiet operation request frame, an IDC quiet operation response frame, and an IDC quiet operation notification frame. This UHR or protected UHR action field may be located in the order of order 2 among the action fields of the IDC quiet operation request / response / notification frame, as illustrated in FIG. 15b.

[0201] According to one embodiment, the category field included in the action field format of the IDC quiet operation request / response / notification frame may include new values ​​assigned for UHR or protected UHR action frames (e.g., 40 and 41 may be applicable, but these values ​​are examples only and may be changed).

[0202] Meanwhile, the structure of the format, field names, values ​​indicated by fields, number of fields to which meaningful values ​​are assigned, order of fields, number of octets or bits, inclusion of fields in the format, etc., shown in FIGS. 15a to 15c are merely examples and may be changed differently from the illustrated and described embodiment.

[0203] FIGS. 16A and 16B illustrate further examples of field formats for IDC quiet operations according to an embodiment of the present disclosure. FIGS. 16A and 16B illustrate a new action frame format proposed for IDC quiet operations according to the embodiments described above.

[0204] According to the embodiments illustrated in FIGS. 16A and 16B, among public action frames, an action frame whose action type is assigned to the QAB (quiet adjacent BSSs) action field may be utilized for the embodiments described above. The QAB action frame may refer to a frame for requesting a quiet period between APs, and the action field values ​​of the public action frame may be assigned to a QAB request frame and a QAB response frame, respectively. The QAB request frame and the QAB response frame may be frames transmitted and received between APs.

[0205] FIG. 16A illustrates an embodiment of utilizing a QAB request frame as a frame for an IDC quiet operation by reinterpreting the value of the QAB request frame action field as illustrated. According to one embodiment, when a QAB request frame is used instead of an IDC quiet requesting frame for an IDC quiet requesting STA to notify an IDC quiet responding AP of quiet period-related information, as illustrated in (a) of FIG. 16A, the RequesterAP address field of the QAB request frame may include a value for indicating an IDC quiet requesting STA address, and the ResponderAP address field of the QAB request frame may include a value for indicating an IDC quiet responding AP address (i.e., an address of an AP associated with the IDC quiet requesting STA). Additionally, as illustrated in (b) of FIG. 16a, the target BSSID field included in the quiet period request element format of the QAB request frame may include a value for indicating at least one address among an IDC quiet requesting STA address or an IDC quiet responding AP address, or may include various other parameters or values ​​described above for the IDC quiet operation, or may include a meaningless value.

[0206] FIG. 16b describes an embodiment in which a QAB response frame is utilized as a frame for an IDC quiet operation by reinterpreting the value of the QAB response frame action field as illustrated. According to one embodiment, when a QAB response frame is used instead of an IDC quiet response frame for an IDC quiet responding AP to transmit quiet period related information to an IDC quiet requesting STA, as illustrated in (a) of FIG. 16b, the RequesterAP address field of the QAB response frame may include a value for indicating an IDC quiet requesting STA address, and the ResponderAP address field of the QAB response frame may include a value for indicating an IDC quiet responding AP address (i.e., an address of an AP associated with the IDC quiet requesting STA).

[0207] Meanwhile, the structure of the format, field names, values ​​indicated by fields, number of fields to which meaningful values ​​are assigned, order of fields, number of octets or bits, inclusion of fields in the format, etc., shown in FIGS. 16a and 16b are merely examples and may be changed differently from the illustrated and described embodiment.

[0208] FIG. 17 illustrates another example of elements and formats for IDC quiet operations according to an embodiment of the present disclosure. FIG. 17 describes a new action frame format proposed for IDC quiet operations according to the embodiments described above.

[0209] According to the embodiment illustrated in FIG. 17, an action frame in which an action type among HE action frames is assigned to a QTP action field may be utilized for the embodiment described above. According to this embodiment, a control subfield in a QTP element of a QTP action frame ((a) of FIG. 17) may include a value for indicating three subtypes for an IDC quiet operation, i.e., an IDC quiet operation request, an IDC quiet operation response, and an IDC quiet operation notification. That is, a control subfield in a QTP element of a QTP action frame may be additionally encoded with three LSBs, for example, QTP subtype field values ​​0 to 2 in the control subfield may be assigned for QTP setup, QTP request, and QTP response, and QTP subtype field values ​​3 to 5 (or 4 to 6) in the control subfield may be additionally assigned for an IDC quiet operation request, an IDC quiet operation response, and an IDC quiet operation notification ((b) of FIG. 17).

[0210] According to the present embodiment, depending on the value of the QTP subtype field, the format of the subsequent quiet time content field may vary to correspond to the QTP subtype field. For example, when the QTP subtype field includes a value indicating an IDC quiet operation request, the quiet time content field may have the content field format of the IDC quiet request element described in FIG. 14c; when the QTP subtype field includes a value indicating an IDC quiet operation response, the quiet time content field may have the content field format of the IDC quiet response element described in FIG. 14d; and when the QTP subtype field includes a value indicating an IDC quiet operation notification, the quiet time content field may have the content field format of the IDC quiet notification element described in FIG. 14e.

[0211] Meanwhile, the structure of the format illustrated in FIG. 17, the field names, the values ​​indicated by the fields, the number of fields to which meaningful values ​​are assigned, the order of the fields, the number of octets or bits, whether fields are included in the format, etc. are merely examples and may, of course, be changed differently from the illustrated and described embodiment.

[0212] FIG. 18 illustrates another example of a field format for IDC quiet operation according to an embodiment of the present disclosure. FIG. 18 describes a new action frame format proposed for IDC quiet operation according to the embodiments described above.

[0213] According to the embodiment illustrated in FIG. 18, a general purpose action frame for various types of communication between an STA and an AP may be utilized as an action frame for an IDC quiet operation. According to one embodiment, two or more values ​​among the reserved values ​​of the action field values ​​46 to 255 of the public action frame may be assigned for the IDC quiet operation. For example, the value 46 may be assigned for an IDC quiet request frame, the value 47 may be assigned for an IDC quiet response frame, and the value 48 may be assigned for an IDC quiet notification frame, respectively. However, these values ​​are merely examples, and it is to be understood that other values ​​may be assigned for each frame.

[0214] According to the embodiment of FIG. 18, when a public action frame is used for an IDC quiet operation, a dialog token field may be included in the IDC quiet operation request element and the IDC quiet operation response element, respectively ((a) and (b) of FIG. 18), and a status code field may be included in the IDC quiet operation response element ((b) of FIG. 18). According to one embodiment, various embodiments described in the format of the content field of the IDC quiet operation request element described in FIG. 14c may be applied to the public action frame of FIG. 18(a), various embodiments described in the format of the content field of the IDC quiet operation response element described in FIG. 14d may be applied to the public action frame of FIG. 18(b), and various embodiments described in the format of the content field of the IDC quiet operation notification element described in FIG. 14e may be applied to the public action frame of FIG. 18(c). If each of the IDC quiet operation request / response / notification elements has a different action type, the body of the frame may have a similar form as described in FIGS. 15a to 15c.

[0215] Meanwhile, the structure of the format illustrated in FIG. 18, the field names, the values ​​indicated by the fields, the number of fields to which meaningful values ​​are assigned, the order of the fields, the number of octets or bits, whether fields are included in the format, etc. are merely examples, and may of course be changed differently from the illustrated and described embodiment.

[0216] FIG. 19 illustrates another example of a field format for IDC quiet operation according to an embodiment of the present disclosure. FIG. 19 describes a new action frame format proposed for IDC quiet operation according to the embodiments described above.

[0217] According to an embodiment illustrated in FIG. 19, one or more action frames defined for QoS purposes may be utilized as action frames for IDC quiet operation. According to one embodiment, two or more values ​​among reserved values ​​of action field values ​​7 to 255 of the QoS action frame may be assigned for the IDC quiet operation. For example, the value 7 may be assigned for an IDC quiet request frame, the value 8 may be assigned for an IDC quiet response frame, and the value 9 may be assigned for an IDC quiet notification frame, respectively. However, these values ​​are merely examples, and it is to be understood that other values ​​may be assigned for each frame.

[0218] According to the embodiment of FIG. 19, when a QoS action frame is used for an IDC quiet operation, a dialog token field may be included in the IDC quiet operation request element and the IDC quiet operation response element, respectively ((a) and (b) of FIG. 19), and a status code field may be included in the IDC quiet operation response element ((b) of FIG. 19). When each of the IDC quiet operation request / response / notification elements has a different action type, the body of the frame may have a similar form as described in FIGS. 15a to 15c. According to one embodiment, various embodiments described in the format of the content field of the IDC quiet operation request element described in FIG. 14c can be applied to the QoS action frame of (a) of FIG. 19, various embodiments described in the format of the content field of the IDC quiet operation response element described in FIG. 14d can be applied to the QoS action frame of (b) of FIG. 19, and various embodiments described in the format of the content field of the IDC quiet operation notification element described in FIG. 14e can be applied to the QoS action frame of (c) of FIG.

[0219] Meanwhile, the structure of the format illustrated in FIG. 19, the field names, the values ​​indicated by the fields, the number of fields to which meaningful values ​​are assigned, the order of the fields, the number of octets or bits, whether fields are included in the format, etc. are merely examples and may, of course, be changed differently from the illustrated and described embodiment.

[0220] FIG. 20 illustrates another example of a field format for an IDC quiet operation according to an embodiment of the present disclosure. FIG. 20 describes an embodiment of performing an IDC quiet operation based on a trigger frame.

[0221] Regarding the IDC quiet operation described above, supporting TXOP-based quiet operation may be necessary to efficiently manage IDCs caused by aperiodic or emergency events. Specifically, to support instantaneous transmissions via heterogeneous technologies or P2P connections, an IDC quiet requesting STA must be able to initiate a TXOP using a trigger frame.

[0222] According to one embodiment, one or more of the values ​​9 to 15 indicated by the trigger type subfield of the trigger frame may be assigned for IDC quiet operation, for example, as illustrated in FIG. 20, the value 9 may be assigned for IDC quiet operation.

[0223] According to this embodiment, an IDC quiet requesting STA may transmit a trigger frame for an IDC quiet operation (e.g., a trigger frame having a trigger type subfield having a value of 9), and the trigger frame may include an IDC quiet operation element according to the embodiments described above in a common information field or may include a part of an IDC quiet operation element. Alternatively, the trigger frame may include an IDC quiet operation element according to the embodiments described above in a trigger dependent common information field or may include a part of an IDC quiet operation element. According to one embodiment, an IDC quiet operation element included in the trigger frame may include an IDC quiet operation request element including at least a control field of an IDC quiet operation request frame. According to one embodiment, a duration field of the trigger frame may be set to have a value equal to or less than a value indicated by a period duration field of an IDC quiet content field.

[0224] An IDC quiet responding AP that receives a trigger frame transmits a response frame to an IDC quiet requesting STA. The IDC quiet operation-related content included in this response frame may include information corresponding to an IDC quiet operation response in which the IDC quiet operation subtype value indicated by the control field of the IDC quiet operation element is 1. In addition, this response frame may have a structure corresponding to any one of the formats according to the various embodiments described above, or may have a structure in a modified form of any one of them.

[0225] If the status code included in the response frame is SUCCESS, the IDC quiet responding AP acknowledges the IDC quiet request STA's request. In this case, the TXOP acquired by the IDC quiet requesting STA may be maintained. Alternatively, the IDC quiet responding AP may transmit an IDC quiet operation notification frame to hold transmissions from neighboring STAs.

[0226] If the status code included in the response frame is REJECT, the IDC quiet responding AP rejects the IDC quiet requesting STA's request. In this case, the TXOP is terminated, and the NAV settings of adjacent STAs may be reset by the CF (contention free)-end field or other means.

[0227] If the status code included in the response frame is COUNTER, the IDC quiet requesting STAP can continuously retransmit a trigger frame in which the value of the trigger type subfield indicates IDC quiet operation (e.g., a trigger frame in which the value of the trigger type subfield is 9) using the counter-proposed values ​​of the IDC quiet responding AP within the TXOP.

[0228] Meanwhile, the structure of the format illustrated in FIG. 20, the field names, the values ​​indicated by the fields, the number of fields to which meaningful values ​​are assigned, the order of the fields, the number of octets or bits, whether fields are included in the format, etc. are merely examples, and may of course be changed differently from the illustrated and described embodiment.

[0229] FIG. 21 illustrates a flowchart of operations for IDC quiet operation of a device according to an embodiment of the present disclosure. FIG. 21 illustrates the operation of the IDC quiet requesting STA proposed in the present disclosure, and some or all of the various embodiments related to the IDC quiet requesting STA described above may be applied identically or similarly to FIG. 21.

[0230] According to the embodiment of FIG. 21, a non-AP STA (i.e., an IDC quiet requesting STA) transmits an IDC quiet request frame (i.e., a frame for an IDC quiet request or a frame including elements related to an IDC quiet request) to an AP (i.e., an IDC quiet responding AP) (2110). Various types, formats, fields, elements, and / or values ​​of the IDC quiet request frame transmitted by the non-AP STA may be applied identically or similarly to the embodiments described above.

[0231] A non-AP STA (i.e., an IDC quiet requesting STA) receives an IDC quiet response frame (i.e., a frame for an IDC quiet response or a frame including elements related to an IDC quiet response) from an AP (i.e., an IDC quiet responding AP) (2120). According to an embodiment, various types, formats, fields, elements, and / or values ​​of the IDC quiet response frame received by the non-AP STA may be applied identically or similarly to the embodiments described above. According to an embodiment, a status code field of the IDC quiet response frame may include a value indicating SUCCESS.

[0232] A non-AP STA (i.e., an IDC quiet requesting STA) receives an IDC quiet notification frame (i.e., a frame for IDC quiet notification or a frame including elements related to IDC quiet notification) from an AP (i.e., an IDC quiet responding AP) (2130). According to an embodiment, various types, formats, fields, elements, and / or values ​​of the IDC quiet notification frame received by the non-AP STA may be applied identically or similarly to the embodiments described above. According to an embodiment, the process of the non-AP receiving the IDC quiet notification frame from the AP may be omitted, and may be replaced with a process of receiving a frame in a different format instead of the IDC quiet notification frame.

[0233] A non-AP STA may operate according to an accepted quiet period based on an IDC quiet notification frame received from an AP (2140). For example, a non-AP STA may not receive scheduling from the AP (or may not expect scheduling by the AP) or may perform limited operations (e.g., may transmit and / or receive only with limited parameters or capabilities) within the quiet period, depending on the parameters (or values) approved according to steps 2110 to 2130 described above.

[0234] Meanwhile, in the above, one embodiment of the operation of the IDC quiet requesting STA and the IDC quiet responding AP has been described based on the flowchart illustrated in FIG. 21, but it is obvious that the operation of the IDC quiet requesting STA and the IDC quiet responding AP may vary depending on other embodiments described above.

[0235] FIG. 22 illustrates a flowchart of operations for IDC quiet operation of a device according to an embodiment of the present disclosure. FIG. 22 illustrates the operation of the IDC quiet requesting STA proposed in the present disclosure, and some or all of the various embodiments related to the IDC quiet requesting STA described above may be applied identically or similarly to FIG. 22.

[0236] According to the embodiment of FIG. 22, a non-AP STA (i.e., an IDC quiet requesting STA) transmits an IDC quiet request frame (i.e., a frame for an IDC quiet request or a frame including elements related to an IDC quiet request) to an AP (i.e., an IDC quiet responding AP) (2210). Various types, formats, fields, elements, and / or values ​​of the IDC quiet request frame transmitted by the non-AP STA may be applied identically or similarly to the embodiments described above.

[0237] A non-AP STA (i.e., an IDC quiet requesting STA) receives an IDC quiet response frame (i.e., a frame for an IDC quiet response or a frame including elements related to an IDC quiet response) from an AP (i.e., an IDC quiet responding AP) (2220). According to an embodiment, various types, formats, fields, elements, and / or values ​​of the IDC quiet response frame received by the non-AP STA may be applied identically or similarly to the embodiments described above. According to an embodiment, the status code field of the IDC quiet response frame may include a value indicating REJECT.

[0238] A non-AP STA (i.e., an IDC quiet requesting STA) that has received an IDC quiet response frame can operate without a quiet period because the quiet period it requested from the AP (i.e., an IDC quiet responding AP) was not granted (2230).

[0239] Meanwhile, in the above, one embodiment of the operation of the IDC quiet requesting STA and the IDC quiet responding AP has been described based on the flowchart illustrated in FIG. 22, but it is obvious that the operation of the IDC quiet requesting STA and the IDC quiet responding AP may vary depending on other embodiments described above.

[0240] FIG. 23 illustrates a flowchart of operations for IDC quiet operation of a device according to an embodiment of the present disclosure. FIG. 23 illustrates the operation of the IDC quiet requesting STA proposed in the present disclosure, and some or all of the various embodiments related to the IDC quiet requesting STA described above may be applied identically or similarly to FIG. 23.

[0241] According to the embodiment of FIG. 23, a non-AP STA (i.e., an IDC quiet requesting STA) transmits an IDC quiet request frame (i.e., a frame for an IDC quiet request or a frame including elements related to an IDC quiet request) to an AP (i.e., an IDC quiet responding AP) (2310). Various types, formats, fields, elements, and / or values ​​of the IDC quiet request frame transmitted by the non-AP STA may be applied identically or similarly to the embodiments described above.

[0242] A non-AP STA (i.e., an IDC quiet requesting STA) receives an IDC quiet response frame (i.e., a frame for an IDC quiet response or a frame including elements related to an IDC quiet response) from an AP (i.e., an IDC quiet responding AP) (2320). According to an embodiment, various types, formats, fields, elements, and / or values ​​of the IDC quiet response frame received by the non-AP STA may be applied identically or similarly to the embodiments described above. According to an embodiment, a status code field of the IDC quiet response frame may include a value indicating COUNTERED. When the status code field is indicated as COUNTERED, the IDC quiet response frame may additionally include values ​​counter-proposed by the AP.

[0243] A non-AP STA (i.e., an IDC quiet requesting STA) transmits a new IDC quiet request frame (i.e., a frame for a new IDC quiet request or a frame including new IDC quiet request related elements) to an AP (i.e., an IDC quiet responding AP) (2330). The new IDC quiet request frame transmitted by the non-AP STA may include parameters different from those of at least some fields included in the IDC quiet request frame transmitted previously in step 2310, or may include values ​​different from those of at least some fields. For example, the IDC quiet request frame transmitted by the non-AP STA in step 2330 may include parameters and / or values ​​counter-proposed by the AP included in the IDC quiet response frame received in step 2320.

[0244] Meanwhile, in the above, one embodiment of the operation of the IDC quiet requesting STA and the IDC quiet responding AP has been described based on the flowchart illustrated in FIG. 23, but it is obvious that the operation of the IDC quiet requesting STA and the IDC quiet responding AP may vary depending on other embodiments described above.

[0245] FIG. 24 illustrates a flowchart of operations for IDC quiet operation of a device according to an embodiment of the present disclosure. FIG. 24 illustrates the operation of the IDC quiet responding AP proposed in the present disclosure, and some or all of the various embodiments related to the IDC quiet responding AP described above may be applied identically or similarly to FIG. 24.

[0246] According to the embodiment of FIG. 24, an AP (i.e., an IDC quiet responding AP) receives an IDC quiet request frame (i.e., a frame for an IDC quiet request or a frame including elements related to an IDC quiet request) from a non-AP STA (i.e., an IDC quiet requesting STA) (2410). Various types, formats, fields, elements, and / or values ​​of the IDC quiet request frame received by the AP may be applied identically or similarly to the embodiments described above.

[0247] An AP (i.e., an IDC quiet responding AP) transmits an IDC quiet response frame (i.e., a frame for an IDC quiet response or a frame including elements related to an IDC quiet response) to a Non-AP STA (i.e., an IDC quiet requesting STA) (2420). According to an embodiment, various types, formats, fields, elements, and / or values ​​of the IDC quiet response frame transmitted by the AP may be applied in the same or similar manner as the embodiments described above. According to an embodiment, a status code field of the IDC quiet response frame may include a value indicating SUCCESS.

[0248] An AP (i.e., an IDC quiet responding AP) transmits an IDC quiet notification frame (i.e., a frame for IDC quiet notification or a frame including elements related to IDC quiet notification) to a non-AP STA (i.e., an IDC quiet requesting STA) (2430). According to an embodiment, various types, formats, fields, elements, and / or values ​​of the IDC quiet notification frame transmitted by the AP may be applied in the same or similar manner as those of the embodiments described above. According to an embodiment, the process of the AP transmitting the IDC quiet notification frame to the non-AP STA may be omitted, and may be replaced with a process of transmitting a frame in a different format instead of the IDC quiet notification frame.

[0249] An AP (i.e., an IDC quiet responding AP) may operate according to an accepted quiet period based on an IDC quiet notification frame transmitted to a non-AP STA (i.e., an IDC quiet requesting STA) (2440). For example, the AP may not schedule a non-AP STA within the quiet period or may perform limited operations with the non-AP STA (e.g., may perform transmission and / or reception with only limited parameters or capabilities) according to parameters (or values) approved according to steps 2310 to 2330 described above.

[0250] Meanwhile, in the above, one embodiment of the operation of the IDC quiet requesting STA and the IDC quiet responding AP has been described based on the flowchart illustrated in FIG. 24, but it is obvious that the operation of the IDC quiet requesting STA and the IDC quiet responding AP may vary depending on other embodiments described above.

[0251] FIG. 25 illustrates a flowchart of operations for IDC quiet operation of a device according to an embodiment of the present disclosure. FIG. 25 illustrates the operation of the IDC quiet responding AP proposed in the present disclosure, and some or all of the various embodiments related to the IDC quiet responding AP described above may be applied identically or similarly to FIG. 25.

[0252] According to the embodiment of FIG. 25, an AP (i.e., an IDC quiet responding AP) receives an IDC quiet request frame (i.e., a frame for an IDC quiet request or a frame including elements related to an IDC quiet request) from a non-AP STA (i.e., an IDC quiet requesting STA) (2510). Various types, formats, fields, elements, and / or values ​​of the IDC quiet request frame received by the AP may be applied identically or similarly to the embodiments described above.

[0253] An AP (i.e., an IDC quiet responding AP) transmits an IDC quiet response frame (i.e., a frame for an IDC quiet response or a frame including elements related to an IDC quiet response) to a Non-AP STA (i.e., an IDC quiet requesting STA) (2520). According to an embodiment, various types, formats, fields, elements, and / or values ​​of the IDC quiet response frame transmitted by the AP may be applied in the same or similar manner as the embodiments described above. According to an embodiment, the status code field of the IDC quiet response frame may include a value indicating REJECT.

[0254] An AP that transmits an IDC quiet response frame (i.e., an IDC quiet responding AP) can operate without a quiet period because the quiet period requested by a non-AP STA (i.e., an IDC quiet requesting STA) was not granted (2530).

[0255] Meanwhile, in the above, one embodiment of the operation of the IDC quiet requesting STA and the IDC quiet responding AP has been described based on the flowchart illustrated in FIG. 25, but it is obvious that the operation of the IDC quiet requesting STA and the IDC quiet responding AP may vary depending on other embodiments described above.

[0256] Fig. 26 illustrates a flowchart of operations for IDC quiet operation of a device according to an embodiment of the present disclosure. Fig. 26 illustrates the operation of the IDC quiet responding AP proposed in the present disclosure, and some or all of the various embodiments related to the IDC quiet responding AP described above may be applied identically or similarly to Fig. 26.

[0257] According to the embodiment of FIG. 26, an AP (i.e., an IDC quiet responding AP) receives an IDC quiet request frame (i.e., a frame for an IDC quiet request or a frame including elements related to an IDC quiet request) from a non-AP STA (i.e., an IDC quiet requesting STA) (2610). Various types, formats, fields, elements, and / or values ​​of the IDC quiet request frame transmitted by the non-AP STA may be applied identically or similarly to the embodiments described above.

[0258] An AP (i.e., an IDC quiet responding AP) transmits an IDC quiet response frame (i.e., a frame for an IDC quiet response or a frame including elements related to an IDC quiet response) to a Non-AP STA (i.e., an IDC quiet requesting STA) (2620). According to an embodiment, various types, formats, fields, elements, and / or values ​​of the IDC quiet response frame transmitted by the AP may be applied in the same or similar manner as those of the embodiments described above. According to an embodiment, a status code field of the IDC quiet response frame may include a value indicating COUNTERED. When the status code field is indicated as COUNTERED, the IDC quiet response frame may additionally include values ​​counter-proposed by the AP.

[0259] An AP (i.e., an IDC quiet responding AP) receives a new IDC quiet request frame (i.e., a frame for a new IDC quiet request or a frame including elements related to a new IDC quiet request) from a non-AP STA (i.e., an IDC quiet requesting STA) (2630). The new IDC quiet request frame received by the AP may include parameters different from those of at least some fields included in the IDC quiet request frame received previously in step 2610, or may include values ​​different from those of at least some fields. For example, the IDC quiet request frame received by the AP in step 2630 may include parameters and / or values ​​counter-proposed by the AP included in the IDC quiet response frame transmitted in step 2620.

[0260] Meanwhile, in the above, one embodiment of the operation of the IDC quiet requesting STA and the IDC quiet responding AP has been described based on the flowchart illustrated in FIG. 26, but it is obvious that the operation of the IDC quiet requesting STA and the IDC quiet responding AP may vary depending on other embodiments described above.

[0261] FIG. 27 illustrates another example of a frame format for IDC quiet operation according to an embodiment of the present disclosure. FIG. 27 describes another action frame format proposed for IDC quiet operation according to the embodiments described above.

[0262] According to the embodiment illustrated in FIG. 27, a frame for a channel usage request and a frame for a channel usage response can be utilized for IDC quiet operation.

[0263] A channel usage request frame may refer to a frame for a non-AP STA to request specified channel usage information from an AP, and may include an exemplary structure illustrated in (a) of FIG. 27. According to one embodiment, a non-AP STA may transmit a channel usage request frame including a TWT element field to an AP to make an agreement of P2P TWT (peer-to-peer target wakeup time) with the AP, and a TWT element of the TWT element field included in the channel usage request frame may include information or a value for notifying a P2P TWT SP (service period). FIG. 27 (a) illustrates an exemplary format of a channel usage request frame according to this embodiment.

[0264] According to one embodiment, when a channel use request frame is utilized for an IDC quiet operation, the channel use request frame may include an IDC element field for the IDC quiet operation. When the exemplary format illustrated in (a) of FIG. 27 is applied, the IDC element field included in the channel use request frame may include some or all of the various fields of the IDC quiet operation request element described above with reference to FIGS. 14a, 14b, and 14c. The IDC element field included in the channel use request frame may include parameters and / or information for an IDC quiet operation within a specific P2P TWT SP according to a TWT element included in the TWT element field (or, corresponding to a TWT element, matched with a TWT element). The IDC element field included in the channel use request frame may include fields or information for indicating various parameters for IDC quiet operation of non-AP STAs and APs within a specific P2P TWT SP according to the TWT element. At least one of the fields described in various embodiments for the IDC quiet operation above, for example, a requested mode field, a radio mode field, a quiet mode field, an interval offset field, an interval duration field, an interval interval field, a repetition count field, a channel field, a number of spatial streams field, or a service specific identifier field, may be included in the IDC element illustrated in (a) of FIG. 27.

[0265] Meanwhile, although (a) of FIG. 27 illustrates an embodiment in which a channel use request frame includes one IDC element field, it is of course possible for the channel use request frame to include multiple IDC element fields. In addition, the structure of the format illustrated in (a) of FIG. 27, the field names, the values ​​indicated by the fields, the number of fields assigned meaningful values, the order of the fields, the number of octets or bits, whether or not fields are included in the format, etc. are merely examples, and it is of course possible to change them differently from the illustrated and described embodiment.

[0266] A channel usage response frame may refer to a frame for an AP to transmit information about specific channel usage information to a non-AP STA, and may include an exemplary structure illustrated in (b) of FIG. 27. According to one embodiment, an AP may respond to a channel usage request frame received from a non-AP STA or may autonomously transmit a channel usage response frame to a non-AP STA.

[0267] According to one embodiment, an AP may transmit a channel usage response frame including a TWT element field to a non-AP STA to make an agreement of P2P TWT with the non-AP STA, and a TWT element of the TWT element field included in the channel usage response frame may include information or a value for notifying an agreed P2P TWT SP. FIG. 27 (b) illustrates an exemplary format of a channel usage response frame according to this embodiment.

[0268] According to one embodiment, when a channel usage response frame is utilized for an IDC quiet operation, the channel usage response frame may include an IDC element field for the IDC quiet operation. When the exemplary format illustrated in (b) of FIG. 27 is applied, the IDC element field included in the channel usage response frame may include some or all of the various fields of the IDC quiet operation response element described above with reference to FIGS. 14a, 14b, and 14d. The IDC element field included in the channel usage response frame may include parameters and / or information for an IDC quiet operation within a specific P2P TWT SP according to a TWT element included in the TWT element field (or, corresponding to a TWT element, matched with a TWT element). The IDC element field included in the channel usage response frame may include fields or information for indicating various parameters for IDC quiet operation of non-AP STAs and APs within a specific P2P TWT SP according to the TWT element. The IDC element according to the example of (b) of FIG. 27 may include parameters or information for notifying a mode of action for an IDC operation to be performed in a specific P2P TWT SP. At least one of the fields described in various embodiments for the IDC quiet operation above, for example, a request mode field, a wireless mode field, a quiet mode field, an interval offset field, an interval duration field, an interval interval field, a repetition count field, a channel field, a number of spatial streams field, or a service specific identifier field, may be included in the IDC element illustrated in (b) of FIG. 27.

[0269] Meanwhile, although (b) of FIG. 27 illustrates an embodiment in which a channel usage response frame includes one IDC element field, it is of course possible for a channel usage response frame to include multiple IDC element fields. In addition, the structure of the format illustrated in (b) of FIG. 27, the field names, the values ​​indicated by the fields, the number of fields assigned meaningful values, the order of the fields, the number of octets or bits, whether or not fields are included in the format, etc. are merely examples, and it is of course possible to change them differently from the illustrated and described embodiment.

[0270] According to the embodiment described in FIG. 27, when a non-AP STA and an AP transmit and receive a channel use request frame and a channel use response frame and negotiate parameters for an IDC operation, the non-AP STA and the AP may perform an IDC operation based on the negotiated parameters for a specific P2P TWT SP. For example, the non-AP STA and the AP may not receive scheduling or may perform limited operations according to the IDC operation in the P2P TWT SP. As another example, the non-AP STA and the AP may not receive scheduling or may perform limited operations according to the IDC operation in a time section other than the P2P TWT SP.

[0271] It goes without saying that the embodiment described in Fig. 27 can be applied to the operations of the non-AP STA and AP described previously in Figs. 21 to 26.

[0272] Meanwhile, FIG. 27 describes an embodiment in which a channel use request frame and a channel use response frame are utilized for IDC quiet operation. However, it goes without saying that any action frame or control frame other than the channel use request frame and the channel use response frame may be utilized for the IDC quiet operation proposed in the present disclosure. Specifically, a non-AP STA and an AP may utilize an action frame and / or a control frame, which include fields (or parameters) for indicating or defining a specific time interval, as a frame for the IDC quiet operation by adding or extending elements for the IDC quiet operation proposed in the present disclosure.

[0273] Meanwhile, the present specification and drawings disclose preferred embodiments of the present disclosure, and although specific terms are used, they are used only in a general sense to easily explain the technical contents of the present disclosure and to help understand the disclosure, and are not intended to limit the scope of the present disclosure.

[0274] Furthermore, it will be apparent to those skilled in the art that, in addition to the embodiments described in this disclosure, other modifications based on the technical concepts of this disclosure are possible. For example, some or all of the contents of one embodiment described above may be combined with some or all of one or more other embodiments, and such combinations are also included in the embodiments proposed in this disclosure.

Claims

1. A method performed by a STA (station) of a wireless local area network (WLAN) system, A step of transmitting a first frame including an IDC quiet request for an IDC (in-device coexistence) quiet period to an AP (access point), wherein a first control field of the first frame includes a value indicating the IDC quiet request and a first content field of the first frame includes at least one parameter for the IDC quiet period; A step of receiving a second frame from the AP, the second frame including an IDC quiet response to the first frame, wherein a second control field of the second frame includes a value for indicating the IDC quiet response and a second content field of the second frame includes a status code field related to the IDC quiet response; and A method comprising a step of supporting and operating a wireless access technology other than the WLAN in the IDC quiet period based on the second frame.

2. In paragraph 1, The above method, A step of receiving a third frame from the AP, including an IDC quiet notification for at least one of setting a Network Allocation Vector (NAV) of an STA other than the STA or stopping the decrease of a backoff counter in relation to the IDC quiet period; and A method wherein the operation in the above IDC quiet section is based on the third frame.

3. In paragraph 1, The status code field included in the second frame indicates one of SUCCESS, REJECT, or COUNTERED, If the above status code field indicates SUCCESS, the STA does not receive scheduling or performs limited operations in the IDC quiet interval, If the above status code field indicates REJECT, the STA performs the operation without considering the IDC quiet period, A method wherein, if the status code field indicates COUNTERED, the STA transmits a fourth frame to the AP that includes a new IDC quiet request based on the value included in the second frame.

4. In paragraph 1, The first control field and the first content field are included in the first IDC quiet operation element of the first frame, The first content field includes at least one of a requested mode field, a radio mode field, a quiet mode field, an interval offset field, an interval duration field, an interval interval field, a repetition count field, a channel field, a number of spatial streams field, or a service specific identifier field. The second control field and the second content field are included in the second IDC quiet operation element of the second frame, A method according to claim 1, wherein the second content field includes at least one of a status code field, a requested mode field, a radio mode field, a quiet mode field, an interval offset field, an interval duration field, an interval interval field, a repetition count field, a channel field, a number of spatial streams field, or a service specific identifier field.

5. In paragraph 1, The above IDC quiet period includes a periodic or instantaneous time period for supporting other wireless access technologies other than the WLAN for the STA, A method wherein the other wireless access technology comprises at least one of P2P (peer to peer) communication, BT (Bluetooth), BLE (Bluetooth low energy), UWB (ultra-wideband), LAA (licensed assisted access), or NR-U (new radio unlicensed).

6. In a method performed by an AP (access point) of a wireless local area network (WLAN) system, A step of receiving, from a STA (station), a first frame including an IDC quiet request for an IDC (in-device coexistence) quiet period, wherein a first control field of the first frame includes a value indicating the IDC quiet request and a first content field of the first frame includes at least one parameter for the IDC quiet period; A step of transmitting a second frame including an IDC quiet response to the first frame to the STA, wherein a second control field of the second frame includes a value for indicating the IDC quiet response and a second content field of the second frame includes a status code field related to the IDC quiet response; and A method comprising a step of performing an operation for the STA by considering a wireless access technology other than the WLAN in the IDC quiet period based on the second frame.

7. In paragraph 6, The above method, A step of transmitting a third frame including an IDC quiet notification for at least one of setting a Network Allocation Vector (NAV) of an STA other than the STA or stopping the decrease of a backoff counter in relation to the IDC quiet period to the STA; and A method wherein the above operation in the above IDC quiet period is based on the third frame.

8. In paragraph 6, The status code field included in the second frame indicates one of SUCCESS, REJECT, or COUNTERED, If the above status code field indicates SUCCESS, the AP does not schedule the STA in the IDC quiet period or performs limited operations; If the above status code field indicates REJECT, the AP performs the operation without considering the IDC quiet period, A method wherein, if the status code field indicates COUNTERED, the AP receives a fourth frame from the STA that includes a new IDC quiet request based on the value contained in the second frame.

9. In the STA (station) of a wireless local area network (WLAN) system, At least one transceiver; At least one processor communicatively coupled to said at least one transceiver; and At least one memory communicatively coupled to said at least one processor and storing instructions, The above instructions are executed individually or in any combination by the at least one processor, so that the STA: Transmitting a first frame including an IDC quiet request for an IDC (in-device coexistence) quiet period to an AP (access point), wherein a first control field of the first frame includes a value for indicating the IDC quiet request and a first content field of the first frame includes at least one parameter for the IDC quiet period, Receive a second frame from the AP that includes an IDC quiet response to the first frame, wherein a second control field of the second frame includes a value for indicating the IDC quiet response, and a second content field of the second frame includes a status code field related to the IDC quiet response; An STA that supports and operates other wireless access technologies other than WLAN in the IDC quiet period based on the second frame.

10. In paragraph 9, The above commands are: In relation to the IDC quiet period, a third frame including an IDC quiet notification for at least one of setting a Network Allocation Vector (NAV) of an STA other than the STA or stopping the decrease of a backoff counter is received from the AP, The operation in the above IDC quiet section is based on the third frame.

11. In paragraph 9, The status code field included in the second frame indicates one of SUCCESS, REJECT, or COUNTERED, If the above status code field indicates SUCCESS, the STA does not receive scheduling or performs limited operations in the IDC quiet interval, If the above status code field indicates REJECT, the STA performs the operation without considering the IDC quiet period, If the status code field indicates COUNTERED, the STA transmits a fourth frame to the AP containing a new IDC quiet request based on the value contained in the second frame.

12. In paragraph 9, The first control field and the first content field are included in the first IDC quiet operation element of the first frame, The first content field includes at least one of a requested mode field, a radio mode field, a quiet mode field, an interval offset field, an interval duration field, an interval interval field, a repetition count field, a channel field, a number of spatial streams field, or a service specific identifier field. The second control field and the second content field are included in the second IDC quiet operation element of the second frame, STA, wherein the second content field includes at least one of a status code field, a requested mode field, a radio mode field, a quiet mode field, an interval offset field, an interval duration field, an interval interval field, a repetition count field, a channel field, a number of spatial streams field, or a service specific identifier field.

13. In the AP (access point) of a wireless local area network (WLAN) system, At least one transceiver; At least one processor communicatively coupled to said at least one transceiver; and At least one memory communicatively coupled to said at least one processor and storing instructions, The above instructions are executed individually or in any combination by the at least one processor, so that the AP: Receiving a first frame including an IDC quiet request for an IDC (in-device coexistence) quiet period from a STA (station), wherein a first control field of the first frame includes a value for indicating the IDC quiet request and a first content field of the first frame includes at least one parameter for the IDC quiet period, Transmitting a second frame including an IDC quiet response to the first frame to the STA, wherein a second control field of the second frame includes a value for indicating the IDC quiet response and a second content field of the second frame includes a status code field related to the IDC quiet response; Based on the second frame, the operation for the STA is performed by considering a wireless access technology other than the WLAN in the IDC quiet period, and the AP.

14. In paragraph 13, The above commands cause the AP to: In relation to the IDC quiet period, a third frame including an IDC quiet notification for at least one of setting a Network Allocation Vector (NAV) of another STA other than the STA or stopping the decrease of a backoff counter is transmitted to the STA, The above operation in the above IDC quiet period is based on the third frame, AP.

15. In paragraph 13, The status code field included in the second frame indicates one of SUCCESS, REJECT, or COUNTERED, If the above status code field indicates SUCCESS, the AP does not schedule the STA in the IDC quiet period or performs limited operations; If the above status code field indicates REJECT, the AP performs the operation without considering the IDC quiet period, If the above status code field indicates COUNTERED, the AP receives a fourth frame from the STA containing a new IDC quiet request based on the value contained in the second frame.

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