Exchange of information for accessing non-primary channel

Abstract

The technical features of the present disclosure may relate to a method or a device performed in a wireless local area network (WLAN) system. For example, the present disclosure may propose a specific technique in which an MLD having the capability of non-primary channel access (NPCA) enables or disables an NPCA mode in consideration of power saving, QoS requirements, and the like. For example, proposed is an example in which signaling information on a mode may be configured on the basis of one link, and information on the NPCA mode for one link may also be transferred through another link on the basis of MLD-level. For example, the information on the NPCA mode may be exchanged between stations (STAs) through a management frame.

Description

Exchange of information for accessing non-primary channels

[0001] The present disclosure relates to a wireless LAN system, and more particularly, to an improved method and device for accessing a channel other than a primary channel of a wireless LAN system.

[0002] Wireless local area networks (WLANs) have been improved in various ways. For example, the Extreme High Throughput (EHT) standard can utilize newly proposed increased bandwidth, an improved PHY layer protocol data unit (PPDU) structure, improved sequences, and Hybrid Automatic Repeat Request (HARQ) techniques. The EHT standard can also be referred to as the IEEE 802.11be standard.

[0003] The EHT specification supports high throughput and high data rates, which may include wide bandwidth (e.g., 160 / 320 MHz), 16 streams, and / or multi-link (or multi-band) operation.

[0004] In the EHT specification, wide bandwidth (e.g., 160 / 240 / 320 MHz) can be used to achieve high throughput. Preamble puncturing and multiple RU transmissions can also be used to efficiently utilize bandwidth.

[0005] WLAN systems can be further improved through the Ultra High Reliability (UHR) standard. The UHR system, also known as the IEEE 802.11bn standard, aims to support ultra-high reliability when transmitting signals to STAs. To achieve this, various technologies are being considered for UHR systems, including high throughput, low latency, and extended range support.

[0006] WLAN systems perform media access based on primary channels. For example, information about a primary channel with a bandwidth of 20 MHz is transmitted to multiple STAs via management frames, and any STA attempting to exchange frames can access the primary channel.

[0007] Currently, the 802.11 BSS Operating Channel can be configured based on a Primary Channel (PCH) and one or more Secondary Channels (SCHs). In order to transmit a frame based on the BSS operating channel, a back-off must always be performed on the PCH, and the back-off counter (BC) of the PCH must be 0. Accordingly, if the PCH is determined to be BUSY, the wireless channel / medium cannot be used. However, according to the prior art, if only the PCH is BUSY and the SCH (or non-primary channel) other than the PCH is in an IDLE state, the SCH cannot be used, which can significantly reduce medium efficiency. To solve this problem, various information must be exchanged to support the operation of accessing the SCH (or non-primary channel).

[0008] This specification proposes various technical features. These technical features can be applied to various types of STAs / devices.

[0009] For example, this specification can propose a specific technique for enabling or disabling the NPCA mode by taking into account power saving, QoS requirements, etc. of an MLD having the capability of NPCA (Non-Primary Channel Access). For example, signaling information about the mode can be set on a link basis, and an example can be proposed in which information about the NPCA mode for another link can also be transmitted through a link based on the MLD level.

[0010] For example, the technical features of the present specification may relate to a method or device performed in a Wireless Local Area Network (WLAN) system. For example, the method of the present specification may include a step of transmitting, by a first STA (Station), a first management frame to a second STA based on a first link. For example, the first STA may be affiliated with a first MLD (Multi-Link Device) that performs a multi-link operation related to a plurality of links, and the second STA may be affiliated with a second MLD that performs a multi-link operation related to the plurality of links. For example, the first management frame may include first bitmap information related to a Non-Primary Channel Access (NPCA) mode performed by the first MLD with respect to the plurality of links.

[0011] For example, the method of the present specification may include a step of receiving, by the first STA, a second management frame from the second STA based on the first link. For example, the second management frame may include second bitmap information related to an NPCA mode performed by the second MLD for the plurality of links.

[0012] The technical features described in this specification can yield various beneficial effects. For example, exchanging information about NPCA Mode according to the technique proposed in this specification enables efficient and flexible communication in response to various traffic conditions. For example, when traffic volume is high, NPCA Mode can be enabled, allowing NPCA to be performed for OBSS traffic reception, improving throughput performance. Similarly, when the traffic to be processed by STAs is low, NPCA Mode can be disabled. This allows for power savings during the OBSS traffic reception period, thereby providing flexibility for MLD STAs to utilize NPCA Mode.

[0013] Figure 1 illustrates an example of a transmitting device and / or a receiving device of the present specification.

[0014] Figure 2 is a conceptual diagram showing the structure of a wireless local area network (WLAN).

[0015] Figure 3 is a diagram illustrating a general link setup process.

[0016] Figure 4 illustrates one embodiment of a multi-link (ML).

[0017] Figure 5 illustrates a PPDU transmitted / received by an STA of this specification.

[0018] Figure 6 is a diagram showing the layout of resource units (RUs) used for 20MHz PPDU.

[0019] Figure 7 is a diagram showing the layout of resource units (RUs) used for 40MHz PPDU.

[0020] Figure 8 is a diagram showing the layout of resource units (RUs) used for 80MHz PPDU.

[0021] Figure 9 shows the operation according to UL-MU.

[0022] Figure 10 shows an example of channels used / supported / defined within the 2.4 GHz band.

[0023] Figure 11 illustrates an example of channels used / supported / defined within the 5 GHz band.

[0024] Figure 12 illustrates an example of channels used / supported / defined within the 6 GHz band.

[0025] Figure 13 shows an example of a header of a MAC frame.

[0026] FIG. 14 illustrates a modified example of a transmitting device and / or a receiving device of the present specification.

[0027] Figure 15 illustrates an example of NAV (network allocation vector) settings.

[0028] Figure 16 shows an example related to primary channel, secondary channel, and channel extension / bonding.

[0029] Figure 17 relates to an example of channel access related to an 80 MHz channel.

[0030] Figure 18 illustrates an example of the SCA process.

[0031] Figure 19 illustrates an example related to the first method of the present specification.

[0032] Figure 20 illustrates an example related to the first method of the present specification.

[0033] Figure 21 illustrates an example related to the second method of the present specification.

[0034] Figure 22 illustrates an example related to the second method of the present specification.

[0035] Figure 23 illustrates an example related to the second method of the present specification.

[0036] Figure 24 illustrates an example related to the third method of the present specification.

[0037] Figure 25 illustrates an example related to the third method of the present specification.

[0038] Figure 26 is a flowchart illustrating an example of the above-described specification.

[0039] Figure 27 is another flowchart illustrating an example of the specification described above.

[0040] Figure 28 is another procedure flowchart illustrating an example of the above-described specification.

[0041] Figure 29 is another procedure flowchart illustrating an example of the above-described specification.

[0042] As used herein, "A or B" can mean "only A," "only B," or "both A and B." In other words, as used herein, "A or B" can be interpreted as "A and / or B." For example, as used herein, "A, B or C" can mean "only A," "only B," "only C," or "any combination of A, B and C."

[0043] As used herein, a slash ( / ) or a comma can mean "and / or." For example, "A / B" can mean "A and / or B." Accordingly, "A / B" can mean "only A," "only B," or "both A and B." For example, "A, B, C" can mean "A, B, or C."

[0044] In this specification, "at least one of A and B" may mean "only A", "only B" or "both A and B". Additionally, in this specification, the expressions "at least one of A or B" or "at least one of A and / or B" may be interpreted identically to "at least one of A and B".

[0045] In addition, parentheses used in this specification may mean "for example". Specifically, when it is indicated as "control information (UHR-Signal field)", the "UHR-Signal field" may be proposed as an example of "control information". In other words, the "control information" in this specification is not limited to the "UHR-Signal field", and the "UHR-Signal field" may be proposed as an example of "control information". In addition, even when it is indicated as "control information (UHR-Signal field)", the "UHR-Signal field" may be proposed as an example of "control information".

[0046] Additionally, as used herein, "a / an" can mean "at least one" or "one or more." Additionally, terms ending in "(s)" can mean "at least one" or "one or more."

[0047] Additionally, the expressions "based on" or "on the basis of" or "according to" used herein mean "based at least in part on" and not "based solely on".

[0048] Technical features individually described in a single drawing in this specification may be implemented individually or simultaneously.

[0049] The following examples of this specification can be applied to various wireless communication systems. For example, the following examples of this specification can be applied to wireless local area network (WLAN) systems. For example, the present specification can be applied to the IEEE 802.11a / g / n / ac / ax / be / bn standards. In addition, the examples of this specification can be applied to the Ultra High Reliability (UHR) standard or the next-generation wireless LAN standard that enhances IEEE 802.11bn. In addition, the examples of this specification can be applied to mobile communication systems. For example, the examples of this specification can be applied to mobile communication systems based on Long Term Evolution (LTE) and its evolution based on the 3rd Generation Partnership Project (3GPP) standard.

[0050] In order to explain the technical features of this specification, the technical features to which this specification can be applied are described below.

[0051] Figure 1 illustrates an example of a transmitting device and / or a receiving device of the present specification.

[0052] An example of FIG. 1 can perform various technical features described below. FIG. 1 relates to at least one STA (station). For example, the STA (110, 120) of the present specification may also be referred to by various names such as a mobile terminal, a wireless device, a Wireless Transmit / Receive Unit (WTRU), a User Equipment (UE), a Mobile Station (MS), a Mobile Subscriber Unit, or simply a user. The STA (110, 120) of the present specification may also be referred to by various names such as a network, a base station, a Node-B, an access point (AP), a repeater, a router, a relay, etc. The STA (110, 120) of the present specification may also be referred to by various names such as a receiving apparatus, a transmitting apparatus, a receiving STA, a transmitting STA, a receiving device, a transmitting device, etc.

[0053] For example, STA (110, 120) may perform the role of an AP (access point) or a non-AP role. That is, STA (110, 120) of the present specification may perform the functions of an AP and / or a non-AP. In the present specification, AP may also be indicated as an AP STA.

[0054] The STA (110, 120) of this specification can support various communication standards other than the IEEE 802.11 standard. For example, it can support communication standards according to the 3GPP standard (e.g., LTE, LTE-A, 5G NR standard). In addition, the STA of this specification can be implemented in various devices such as mobile phones, vehicles, and personal computers. In addition, the STA of this specification can support communication for various communication services such as voice calls, video calls, data communications, and autonomous driving (Self-Driving, Autonomous-Driving).

[0055] In this specification, STA (110, 120) may include a medium access control (MAC) and a physical layer interface for a wireless medium that follow the provisions of the IEEE 802.11 standard.

[0056] Based on the sub-drawing (a) of Fig. 1, STA (110, 120) is described as follows.

[0057] The first STA (110) may include a processor (111), a memory (112), and a transceiver (113). The illustrated processor, memory, and transceiver may each be implemented as separate chips, or at least two blocks / functions may be implemented through a single chip.

[0058] The transceiver (113) of the first STA performs signal transmission and reception operations. Specifically, it can transmit and receive IEEE 802.11 packets (e.g., IEEE 802.11a / b / g / n / ac / ax / be, etc.).

[0059] For example, the first STA (110) can perform the intended operation of the AP. For example, the processor (111) of the AP can receive a signal through the transceiver (113), process the received signal, generate a transmission signal, and perform control for signal transmission. The memory (112) of the AP can store a signal received through the transceiver (113) (i.e., a reception signal) and store a signal to be transmitted through the transceiver (i.e., a transmission signal).

[0060] For example, the second STA (120) can perform the intended operation of a non-AP STA. For example, the transceiver (123) of the non-AP performs signal transmission and reception operations. Specifically, it can transmit and receive IEEE 802.11 packets (e.g., IEEE 802.11a / b / g / n / ac / ax / be, etc.).

[0061] For example, the processor (121) of the Non-AP STA can receive a signal through the transceiver (123), process the received signal, generate a transmission signal, and perform control for signal transmission. The memory (122) of the Non-AP STA can store a signal received through the transceiver (123) (i.e., a reception signal) and store a signal to be transmitted through the transceiver (i.e., a transmission signal).

[0062] For example, in the specification below, the operation of a device indicated as AP may be performed in the first STA (110) or the second STA (120). For example, if the first STA (110) is an AP, the operation of the device indicated as AP may be controlled by the processor (111) of the first STA (110), and a related signal may be transmitted or received through a transceiver (113) controlled by the processor (111) of the first STA (110). In addition, control information related to the operation of the AP or a transmission / reception signal of the AP may be stored in the memory (112) of the first STA (110). In addition, when the second STA (110) is an AP, the operation of the device indicated as an AP is controlled by the processor (121) of the second STA (120), and a related signal can be transmitted or received through a transceiver (123) controlled by the processor (121) of the second STA (120). In addition, control information related to the operation of the AP or the transmission / reception signal of the AP can be stored in the memory (122) of the second STA (110).

[0063] For example, in the specification below, the operation of a device indicated as a non-AP (or User-STA) may be performed in the STA (110) or the second STA (120). For example, if the second STA (120) is a non-AP, the operation of the device indicated as a non-AP may be controlled by the processor (121) of the second STA (120), and a related signal may be transmitted or received through a transceiver (123) controlled by the processor (121) of the second STA (120). In addition, control information related to the operation of the non-AP or the transmission / reception signal of the AP may be stored in the memory (122) of the second STA (120). For example, if the first STA (110) is a non-AP, the operation of a device indicated as a non-AP is controlled by the processor (111) of the first STA (110), and a related signal may be transmitted or received through a transceiver (113) controlled by the processor (111) of the first STA (120). In addition, control information related to the operation of the non-AP or the transmission / reception signal of the AP may be stored in the memory (112) of the first STA (110).

[0064] In the following specification, devices called (transmitting / receiving) STA, first STA, second STA, STA1, STA2, AP, first AP, second AP, AP1, AP2, (transmitting / receiving) Terminal, (transmitting / receiving) device, (transmitting / receiving) apparatus, network, etc. may refer to the STA (110, 120) of FIG. 1. For example, devices indicated as (transmitting / receiving) STA, first STA, second STA, STA1, STA2, AP, first AP, second AP, AP1, AP2, (transmitting / receiving) Terminal, (transmitting / receiving) device, (transmitting / receiving) apparatus, network, etc. without specific drawing symbols may also refer to the STA (110, 120) of FIG. 1. For example, in the example below, the operation of various STAs transmitting and receiving signals (e.g., PPPDU) may be performed by the transceiver (113, 123) of FIG. 1. In addition, in the example below, the operation of various STAs generating transmission and reception signals or performing data processing or calculations in advance for transmission and reception signals may be performed by the processor (111, 121) of FIG. 1.For example, an example of an operation that generates a transmission / reception signal or performs data processing or operation in advance for a transmission / reception signal may include 1) an operation of determining / obtaining / configuring / computing / decoding / encoding bit information of a subfield (SIG, STF, LTF, Data) field included in a PPDU, 2) an operation of determining / configuring / obtaining time resources or frequency resources (e.g., subcarrier resources) used for a subfield (SIG, STF, LTF, Data) field included in a PPDU, 3) an operation of determining / configuring / obtaining a specific sequence (e.g., a pilot sequence, an STF / LTF sequence, an extra sequence applied to SIG) used for a subfield (SIG, STF, LTF, Data) field included in a PPDU, 4) a power control operation and / or a power saving operation applied to an STA, 5) an operation related to determining / obtaining / configuring / computing / decoding / encoding an ACK signal, etc. Additionally, in the examples below, various information (e.g., information related to fields / subfields / control fields / parameters / power, etc.) used by various STAs for determining / acquiring / configuring / computing / decoding / encoding transmission / reception signals can be stored in the memory (112, 122) of FIG. 1.

[0065] The device / STA of the sub-drawing (a) of the above-described FIG. 1 can be modified as in the sub-drawing (b) of FIG. 1. Hereinafter, the STA (110, 120) of the present specification will be described based on the sub-drawing (b) of FIG. 1.

[0066] For example, the transceiver (113, 123) illustrated in sub-drawing (b) of FIG. 1 may perform the same function as the transceiver illustrated in sub-drawing (a) of FIG. 1 described above. For example, the processing chip (114, 124) illustrated in sub-drawing (b) of FIG. 1 may include a processor (111, 121) and a memory (112, 122). The processor (111, 121) and the memory (112, 122) illustrated in sub-drawing (b) of FIG. 1 may perform the same function as the processor (111, 121) and the memory (112, 122) illustrated in sub-drawing (a) of FIG. 1 described above.

[0067] The mobile terminal, wireless device, Wireless Transmit / Receive Unit (WTRU), User Equipment (UE), Mobile Station (MS), Mobile Subscriber Unit, user, user STA, network, Base Station, Node-B, Access Point (AP), repeater, router, relay, receiving device, transmitting device, receiving STA, transmitting STA, receiving Device, transmitting Device, receiving Apparatus, and / or transmitting Apparatus described below may refer to the STA (110, 120) illustrated in the sub-drawings (a) / (b) of FIG. 1, or may refer to the processing chip (114, 124) illustrated in the sub-drawing (b) of FIG. 1. That is, the technical feature of the present specification may be performed in the STA (110, 120) illustrated in the sub-drawings (a) / (b) of FIG. 1, or may be performed only in the processing chip (114, 124) illustrated in the sub-drawings (b) of FIG. 1. For example, the technical feature that the transmitting STA transmits a control signal may be understood as a technical feature that the control signal generated in the processor (111, 121) illustrated in the sub-drawings (a) / (b) of FIG. 1 is transmitted through the transceiver (113, 123) illustrated in the sub-drawings (a) / (b) of FIG. 1. Alternatively, the technical feature that the transmitting STA transmits a control signal may be understood as a technical feature that the control signal to be transmitted to the transceiver (113, 123) is generated in the processing chip (114, 124) illustrated in the sub-drawings (b) of FIG. 1.

[0068] For example, the technical feature of a receiving STA receiving a control signal can be understood as a technical feature of a control signal being received by a transceiver (113, 123) illustrated in sub-drawing (a) of FIG. 1. Alternatively, the technical feature of a receiving STA receiving a control signal can be understood as a technical feature of a control signal received by a transceiver (113, 123) illustrated in sub-drawing (a) of FIG. 1 being acquired by a processor (111, 121) illustrated in sub-drawing (a) of FIG. 1. Alternatively, the technical feature of a receiving STA receiving a control signal can be understood as a technical feature of a control signal received by a transceiver (113, 123) illustrated in sub-drawing (b) of FIG. 1 being acquired by a processing chip (114, 124) illustrated in sub-drawing (b) of FIG.

[0069] Referring to the sub-drawing (b) of FIG. 1, software code (115, 125) may be included in the memory (112, 122). The software code (115, 125) may include instructions that control the operation of the processor (111, 121). The software code (115, 125) may be included in various programming languages.

[0070] The processor (111, 121) or processing chip (114, 124) illustrated in FIG. 1 may include an application-specific integrated circuit (ASIC), another chipset, a logic circuit, and / or a data processing device. The processor may be an application processor (AP). For example, the processor (111, 121) or processing chip (114, 124) illustrated in FIG. 1 may include at least one of a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), and a modem (modulator and demodulator). For example, the processor (111, 121) or processing chip (114, 124) illustrated in FIG. 1 may be a SNAPDRAGON® series processor manufactured by Qualcomm®, an EXYNOS® series processor manufactured by Samsung®, an A series processor manufactured by Apple®, a HELIO® series processor manufactured by MediaTek®, an ATOM® series processor manufactured by INTEL®, or an enhanced processor thereof.

[0071] In this specification, uplink may mean a link for communication from a non-AP STA to an AP STA, and uplink PPDU / packet / signal, etc. may be transmitted through the uplink. In addition, in this specification, downlink may mean a link for communication from an AP STA to a non-AP STA, and downlink PPDU / packet / signal, etc. may be transmitted through the downlink.

[0072] Figure 2 is a conceptual diagram showing the structure of a wireless local area network (WLAN).

[0073] The upper part of Figure 2 shows the structure of the infrastructure BSS (basic service set) of IEEE (institute of electrical and electronic engineers) 802.11.

[0074] Referring to the top of FIG. 2, the wireless LAN system may include one or more infrastructure BSSs (200, 205) (hereinafter, BSS). The BSSs (200, 205) are a collection of APs and STAs, such as an access point (AP) 225 and a station (STA1, 200-1), that have successfully synchronized and can communicate with each other, and are not a concept that designates a specific area. The BSS (205) may also include one or more STAs (205-1, 205-2) that can be associated with one AP (230).

[0075] A BSS may include at least one STA, an AP (225, 230) providing a distribution service, and a distribution system (DS, 210) connecting multiple APs.

[0076] A distributed system (210) can connect multiple BSSs (200, 205) to implement an extended service set (ESS) 240. An ESS (240) can be used as a term to indicate a network formed by connecting one or more APs through the distributed system (210). APs included in a single ESS (240) can have the same SSID (service set identification).

[0077] The portal (portal, 220) can act as a bridge to connect a wireless LAN network (IEEE 802.11) to another network (e.g., 802.X).

[0078] In a BSS such as the upper part of Fig. 2, a network between APs (225, 230) and a network between APs (225, 230) and STAs (200-1, 205-1, 205-2) can be implemented. However, it may also be possible to establish a network and perform communication between STAs without an AP (225, 230). A network that establishes a network and performs communication between STAs without an AP (225, 230) is defined as an ad-hoc network or an independent basic service set (IBSS).

[0079] The bottom of Figure 2 is a conceptual diagram showing IBSS.

[0080] Referring to the bottom of Fig. 2, the IBSS is a BSS that operates in ad-hoc mode. Since the IBSS does not include an AP, there is no centralized management entity. That is, in the IBSS, the STAs (250-1, 250-2, 250-3, 255-4, 255-5) are managed in a distributed manner. In the IBSS, all STAs (250-1, 250-2, 250-3, 255-4, 255-5) can be mobile STAs, and access to the distributed system is not permitted, forming a self-contained network.

[0081] Figure 3 is a diagram illustrating a general link setup process.

[0082] In step S310, the STA may perform a network discovery operation. This network discovery operation may include scanning by the STA. That is, for the STA to access the network, it must find a network it can join. Before joining a wireless network, the STA must identify compatible networks. The process of identifying networks in a specific area is called scanning. Scanning methods include active scanning and passive scanning.

[0083] 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 which APs exist in the vicinity while moving between channels and waits for a response. A responder transmits a probe response frame to the STA that transmitted the probe request frame in response to 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 a BSS, the AP transmits the beacon frame, so the AP becomes the responder. In an IBSS, the STAs within the IBSS take turns transmitting beacon frames, so the responder is not constant. 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.

[0084] Although not shown in the example of FIG. 3, the scanning operation can also be performed in a passive scanning manner. An STA performing scanning based on passive scanning can wait for a beacon frame while moving between channels. A beacon frame is one of the management frames in IEEE 802.11. It announces the presence of a wireless network and is periodically transmitted so that the scanning STA can find the wireless network and participate in the wireless network. In the BSS, the AP periodically transmits the beacon frame, and in the IBSS, the STAs within the IBSS take turns transmitting the beacon frame. When the scanning STA 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. An STA that receives a beacon frame can store the BSS-related information included in the received beacon frame, move to the next channel, and perform scanning on the next channel in the same manner.

[0085] An STA that discovers a network can perform an authentication process through step S320. This authentication process may be referred to as the first authentication process to clearly distinguish it from the security setup operation of step S340 described below. The authentication process of S320 may include a process in which the STA transmits an authentication request frame to the AP, and the AP responds by transmitting an authentication response frame to the STA. The authentication frame used for the authentication request / response corresponds to a management frame.

[0086] 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.

[0087] 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.

[0088] A successfully authenticated STA may perform an association process based on step S330. The association process includes a process in which the STA transmits an association request frame to the AP, and the AP transmits an association response frame to the STA in response. For example, the association request frame may include information related to various capabilities, such as a beacon listen interval, a service set identifier (SSID), supported rates, supported channels, RSN, mobility domain, supported operating classes, a Traffic Indication Map Broadcast request, and interworking service capabilities. For example, the association response frame may contain information related to various capabilities, status codes, Association ID (AID), supported rates, Enhanced Distributed Channel Access (EDCA) parameter sets, Received Channel Power Indicator (RCPI), Received Signal to Noise Indicator (RSNI), mobility domains, timeout interval (association comeback time), overlapping BSS scan parameters, TIM broadcast response, QoS maps, etc.

[0089] In step S340, the STA may perform a security setup process. The security setup process of step S340 may include, for example, a process of setting up a private key through a four-way handshaking using an Extensible Authentication Protocol over LAN (EAPOL) frame.

[0090] Figure 4 illustrates one embodiment of a multi-link (ML).

[0091] As illustrated in FIG. 4, multiple multi-link devices (MLDs) can communicate over a remote link. The MLDs can be categorized into AP MLDs including multiple AP STAs and non-AP MLDs including multiple non-AP STAs. That is, the AP MLD can include affiliated APs (i.e., AP STAs), and the non-AP MLD can include affiliated STAs (i.e., non-AP STAs, or user-STAs).

[0092] A multilink may include a first link and a second link, and different channels / subchannels / frequency resources may be allocated to the first and second links. The first and second multilinks may be identified through a link ID of 4 bits (or other n bits). The first and second links may be configured in the same 2.4 GHz, 5 GHz, or 6 GHz band. Alternatively, the first link and the second link may be configured in different bands.

[0093] The AP MLD of FIG. 4 includes three affiliated APs. In the example of FIG. 4, AP1 may operate in the 2.4 GHz band, AP2 may operate in the 5 GHz band, and AP3 may operate in the 6 GHz band. In the example of FIG. 4, the first link in which AP1 and non-AP1 operate may be defined as a channel / subchannel / frequency resource within the 2.4 GHz band. Furthermore, in the example of FIG. 4, the second link in which AP2 and non-AP2 operate may be defined as a channel / subchannel / frequency resource within the 5 GHz band. Furthermore, in the example of FIG. 4, the third link in which AP3 and non-AP3 operate may be defined as a channel / subchannel / frequency resource within the 6 GHz band.

[0094] In the example of FIG. 4, AP1 may initiate a multi-link setup procedure (ML setup procedure) by transmitting an Association Request frame to non-AP STA1. In the example of FIG. 4, non-AP STA1 may transmit an Association Response frame in response to the Association Request frame. Each AP (e.g., AP1 / 2 / 3) illustrated in FIG. 4 may be identical to the AP illustrated in FIG. 1 and / or FIG. 2, and each non-AP (e.g., non-AP1 / 2 / 3) illustrated in FIG. 4 may be identical to the STA (i.e., user-STA or non-AP STA) illustrated in FIG. 1 and / or FIG. 2.

[0095] The specific features of this specification are not limited to the specific features of FIG. 4. That is, the number of links can be defined in various ways, and multiple links can be defined in various ways within at least one band.

[0096] FIG. 5 illustrates a PPDU (physical protocol data unit or physical layer (PHY) protocol data unit) transmitted / received by an STA of this specification.

[0097] The STA (e.g., AP STA, non-AP STA, AP MLD, non-AP MLD) of the present specification can transmit and / or receive the PPDU of FIG. 5. The PPDU described in the present specification may have, for example, the structure of FIG. 5. In addition, the PPDU described in the present specification may be called by various names such as a transmission PPDU, a reception PPDU, a first type PPDU, or an Nth type PPDU, etc. The PPDU described in the present specification can be used in a WLAN system defined according to IEEE 802.11bn and / or a next-generation WLAN system that improves IEEE 802.11bn.

[0098] The PPDU of FIG. 5 may be related to various PPDU types used in a UHR system. For example, the example of FIG. 5 may be used for at least one of a single-user (SU) mode / type / transmission, a multi-user (MU) mode / type / transmission, and a null data packet (NDP) mode / type / transmission related to channel sounding. For example, if the example of FIG. 5 is related to NDP, the Data field illustrated may be omitted. If the PPDU of FIG. 5 is used for a trigger-based (TB) mode, the UHR-SIG of FIG. 5 may be omitted. In other words, an STA that has received a trigger frame for UL-MU (Uplink-MU) communication may transmit a PPDU with the UHR-SIG omitted in the example of FIG. 5.

[0099] In FIG. 5, L-STF or UHR-LTF may be called a preamble or physical preamble, and may be generated / transmitted / received / acquired / decoded in the physical layer (included in the transmitting / receiving STA).

[0100] Each block illustrated in Fig. 5 may be called a field / subfield / signal, etc. The names of these fields / subfields / signals may be, as illustrated in Fig. 5, L-STF (legacy short training field), L-LTF (legacy long training field), L-SIG (legacy signal), RL-SIG (repeated L-SIG), U-SIG (Universal Signal), UHR-SIG (UHR-signal), etc.

[0101] The subcarrier spacing of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and UHR-SIG fields in FIG. 5 may be set to 312.5 kHz, and the subcarrier spacing of the UHR-STF, UHR-LTF, and Data fields may be set to 78.125 kHz. That is, the tone index (or subcarrier index) of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and UHR-SIG fields may be expressed in units of 312.5 kHz, and the tone index (or subcarrier index) of the UHR-STF, UHR-LTF, and Data fields may be expressed in units of 78.125 kHz.

[0102] In the PPDU of Fig. 5, L-LTF and L-STF may be identical to conventional fields (e.g., non-HT LTF and non-HT STF defined in conventional WLAN standards).

[0103] The L-SIG field of FIG. 5 may include, for example, 24 bits of bit information. For example, the 24 bits of information may include a 4 bit Rate field, a 1 bit Reserved bit, a 12 bit Length field, a 1 bit Parity bit, and a 6 bit Tail bit. For example, the 12 bit Length field may include information about the length or time duration of the PPDU. For example, the value of the 12 bit Length field may be determined based on the type of the PPDU. For example, if the PPDU is a non-HT (non-High Throughput), HT (High Throughput), VHT (Very High Throughput) PPDU, or an EHT (extremely high throughput) PPDU or UHR PPDU, the value of the Length field may be determined as a multiple of 3. For example, if the PPDU is a HE PPDU, the value of the Length field may be determined as "a multiple of 3 + 1" or "a multiple of 3 + 2". In other words, for non-HT, HT, VHT PPDU, EHT PPDU, UHR PPDU, the value of the Length field can be determined as a multiple of 3, and for HE (High Efficiency) PPDU, the value of the Length field can be determined as "a multiple of 3 + 1" or "a multiple of 3 + 2". In other words, the Length field in an UHR PPDU is set to a value satisfying the condition that the remainder is zero when LENGTH is divided by 3.

[0104] For example, (non-AP and AP) STAs can apply BCC encoding based on a code rate of 1 / 2 to the 24 bits of information in the L-SIG field. Then, the transmitting STA can obtain 48 BCC coded bits. BPSK modulation can be applied to the 48 coded bits to generate 48 BPSK symbols. The transmitting STA can map the 48 BPSK symbols to positions excluding the pilot subcarriers {subcarrier index -21, -7, +7, +21} and the DC subcarrier {subcarrier index 0}. As a result, the 48 BPSK symbols can be mapped to subcarrier indices -26 to -22, -20 to -8, -6 to -1, +1 to +6, +8 to +20, and +22 to +26. The transmitting STA can additionally map the signal {-1, -1, -1, 1} to the subcarrier indices {-28, -27, +27, +28}. The above signal can be used for channel estimation for the frequency domain corresponding to {-28, -27, +27, +28}.

[0105] For example, (non-AP and AP) STA can generate RL-SIG, which is generated in the same manner as L-SIG. BPSK modulation can be applied to RL-SIG. Receiving (non-AP and AP) STA can determine whether the received PPDU is a HE PPDU, EHT PPDU, or UHR PPDU based on the presence of RL-SIG. In other words, if RL-SIG is present, receiving (non-AP and AP) STA can determine whether the received PPDU is one of HE PPDU, EHT PPDU, or UHR PPDU. In other words, if RL-SIG is not present, receiving (non-AP and AP) STA can determine whether the received PPDU is one of non-HT PPDU, HT PPDU, or VHT PPDU. In other words, the RL-SIG field is a repeat of the L-SIG field and is used to differentiate an UHR PPDU from a non-HT PPDU, HT PPDU, and VHT PPDU.

[0106] After the RL-SIG in Fig. 5, a U-SIG (Universal SIG) may be inserted. The U-SIG may be called by various names such as the first SIG field, the first SIG, the first type SIG, the control signal, the control signal field, the first (type) control signal, the common control field, and the common control signal.

[0107] A U-SIG can contain N bits of information and can include information for identifying the type of EHT PPDU. For example, a U-SIG can be formed based on two symbols (e.g., two consecutive OFDM symbols). Each symbol (e.g., an OFDM symbol) for a U-SIG can have a duration of 4 microseconds. Each symbol of a U-SIG can be used to transmit 26 bits of information. For example, each symbol of a U-SIG can be transmitted and received based on 52 data tones and 4 pilot tones.

[0108] For example, A bit information (e.g., 52 uncoded bits) can be transmitted through U-SIG, and the first symbol of U-SIG can transmit the first X bits of information (e.g., 26 uncoded bits) out of the total A bit information, and the second symbol of U-SIG can transmit the remaining Y bits of information (e.g., 26 uncoded bits) out of the total A bit information. For example, the transmitting STA can obtain 26 uncoded bits included in each U-SIG symbol. The transmitting STA can perform convolutional encoding (i.e., BCC encoding) based on a rate of R=1 / 2 to generate 52 coded bits, and perform interleaving on the 52 coded bits. The transmitting STA can perform BPSK modulation on the interleaved 52 coded bits to generate 52 BPSK symbols allocated to each U-SIG symbol. A single U-SIG symbol can be transmitted based on 56 tones (subcarriers) from subcarrier index -28 to subcarrier index +28, excluding DC index 0. The 52 BPSK symbols generated by the transmitting STA can be transmitted based on the remaining tones (subcarriers) excluding the pilot tones -21, -7, +7, and +21.

[0109] For example, A bit information (e.g., 52 uncoded bits) transmitted by U-SIG may include a CRC field (e.g., a 4-bit long field) and a tail field (e.g., a 6-bit long field). The CRC field and the tail field may be transmitted through the second symbol of the U-SIG. The CRC field may be generated based on 26 bits allocated to the first symbol of the U-SIG and the remaining 16 bits excluding the CRC / tail field within the second symbol, and may be generated based on a conventional CRC calculation algorithm. In addition, the tail field may be used to terminate the trellis of the convolutional decoder and may be set to, for example, "000000".

[0110] The A bit information (e.g., 52 uncoded bits) transmitted by the U-SIG (or U-SIG field) can be divided into version-independent bits and version-dependent bits. For example, the size of the version-independent bits can be fixed or variable. For example, the version-independent bits can be assigned only to the first symbol of the U-SIG, or the version-independent bits can be assigned to both the first symbol and the second symbol of the U-SIG. For example, the version-independent bits and the version-dependent bits can be called by various names, such as the first control bit and the second control bit.

[0111] For example, the version-independent bits of the U-SIG may include a 3-bit PHY version identifier. For example, the 3-bit PHY version identifier may include information related to the PHY version of the transmitted and received PPDU. For example, a first value (e.g., a value of 000) of the 3-bit PHY version identifier may indicate that the transmitted and received PPDU is an EHT PPDU. In addition, a second value (e.g., a value of 001) of the 3-bit PHY version identifier may indicate that the transmitted and received PPDU is an UHR PPDU.

[0112] In other words, when the (AP / non-AP) STA transmits an EHT PPDU, it can set the 3-bit PHY version identifier to the first value. In other words, the receiving (AP / non-AP) STA can determine that the received PPDU is an EHT PPDU based on the PHY version identifier having the first value, and can determine that the received PPDU is an UHR PPDU based on the PHY version identifier having the second value.

[0113] For example, the version-independent bits of U-SIG may include a 1-bit UL / DL flag field. The first value of the 1-bit UL / DL flag field relates to UL communication, and the second value of the UL / DL flag field relates to DL communication.

[0114] For example, the version-independent bits of U-SIG may contain information about the length of the TXOP and information about the BSS color ID.

[0115] For example, if a UHR PPDU is classified into various types (e.g., a type related to SU transmission (performed based on UL or DL), a type related to DL transmission, a type related to NDP transmission, a type related to DL non-MU-MIMO, a type related to DL MU-MIMO, a type related to Multi-AP operation, a type related to CBF (Coordinated beamforming), SR (Spatial Reuse), a type related to C-OFDMA (Coordinated OFDMA), a type related to C-TDMA (Coordinated TDMA)), information about the type of the EHT PPDU (e.g., 2-bit or 3-bit information) can be included in the version-dependent bits of the U-SIG.

[0116] For example, U-SIG may include 1) a bandwidth field including information about bandwidth, 2) a field including information about a Modulation and Coding Scheme (MCS) technique applied to UHR-SIG, 3) an indication field including information about whether a dual subcarrier modulation (DCM) technique is applied to UHR-SIG, 4) a field including information about the number of symbols used for UHR-SIG, 5) a field including information about whether UHR-SIG is generated over the entire band, 6) a field including information about the type of UHR-LTF / STF, and 7) a field indicating the length of UHR-LTF and the CP length.

[0117] Preamble puncturing may be applied to the PPDU of FIG. 5. Preamble puncturing refers to applying puncturing to a portion of the entire bandwidth of the PPDU (e.g., the secondary 20 MHz band). For example, when an 80 MHz PPDU is transmitted, the STA applies puncturing to the secondary 20 MHz band within the 80 MHz band, and can transmit the PPDU only through the primary 20 MHz band and the secondary 40 MHz band.

[0118] For example, the pattern of preamble puncturing can be preset. For example, when the first puncturing pattern is applied, puncturing can be applied only to the secondary 20 MHz band within the 80 MHz band. For example, when the second puncturing pattern is applied, puncturing can be applied only to one of the two secondary 20 MHz bands included in the secondary 40 MHz band within the 80 MHz band. For example, when the third puncturing pattern is applied, puncturing can be applied only to the secondary 20 MHz band included in the primary 80 MHz band within the 160 MHz band (or 80+80 MHz band). For example, when the fourth puncturing pattern is applied, a primary 40 MHz band included in the primary 80 MHz band within the 160 MHz band (or 80+80 MHz band) may be present, and puncturing may be applied to at least one 20 MHz channel that does not belong to the primary 40 MHz band.

[0119] Information regarding preamble puncturing applied to the PPDU may be included in the U-SIG and / or UHR-SIG. For example, the first field of the U-SIG may include information regarding the contiguous bandwidth of the PPDU, and the second field of the U-SIG may include information regarding preamble puncturing applied to the PPDU.

[0120] For example, U-SIG and UHR-SIG may include information regarding preamble puncturing based on the following method. If the bandwidth of the PPDU exceeds 80 MHz, the U-SIG may be individually configured in units of 80 MHz. For example, if the bandwidth of the PPDU is 160 MHz, the PPDU may include a first U-SIG for the first 80 MHz band and a second U-SIG for the second 80 MHz band. In this case, the first field of the first U-SIG may include information regarding the 160 MHz bandwidth, and the second field of the first U-SIG may include information regarding preamble puncturing applied to the first 80 MHz band (i.e., information regarding the preamble puncturing pattern). Additionally, the first field of the second U-SIG may include information about a 160 MHz bandwidth, and the second field of the second U-SIG may include information about preamble puncturing applied to the second 80 MHz band (i.e., information about a preamble puncturing pattern). Meanwhile, the UHR-SIG consecutive to the first U-SIG may include information about preamble puncturing applied to the second 80 MHz band (i.e., information about a preamble puncturing pattern), and the UHR-SIG consecutive to the second U-SIG may include information about preamble puncturing applied to the first 80 MHz band (i.e., information about a preamble puncturing pattern).

[0121] Additionally or alternatively, U-SIG and UHR-SIG may include information regarding preamble puncturing based on the following methods. U-SIG may include information regarding preamble puncturing for all bands (i.e., information regarding preamble puncturing patterns). That is, UHR-SIG may not include information regarding preamble puncturing, and only U-SIG may include information regarding preamble puncturing (i.e., information regarding preamble puncturing patterns).

[0122] U-SIGs can be configured in 20 MHz units. For example, if an 80 MHz PPDU is configured, U-SIGs can be duplicated. That is, four identical U-SIGs can be included within an 80 MHz PPDU. PPDUs exceeding the 80 MHz bandwidth can contain different U-SIGs.

[0123] The UHR-SIG of FIG. 5 may include control information for a receiving STA. The UHR-SIG may be transmitted via at least one symbol, and each symbol may have a length of 4 us. Information regarding the number of symbols used for the UHR-SIG may be included in the U-SIG.

[0124] UHR-SIG provides additional signals to the U-SIG field to enable STAs to interpret / decode UHR PPDUs. The UHR-SIG field may contain U-SIG overflow bits that are common to all users. The UHR-SIG field also contains resource allocation information, allowing STAs to look up resources used in fields containing data fields / UHR-STF / UHR-LTF (i.e., UHR modulated fields of an UHR PPDU).

[0125] The frequency resources of the UHR-LTF, UHR-STF, and data fields illustrated in FIG. 5 can be determined based on RUs (resource units) defined by multiple subcarriers / tones. That is, the UHR-LTF, UHR-STF, and data fields of this specification can be transmitted / received through RUs (resource units) defined by multiple subcarriers / tones.

[0126] FIG. 6 is a diagram illustrating the layout of resource units (RUs) used for a 20 MHz PPDU. That is, the UHR-LTF, UHR-STF, and / or data fields included in the 20 MHz PPDU can be transmitted / received through at least one of the various RUs defined in FIG. 6.

[0127] As shown at the top of Fig. 6, 26 units (i.e., units corresponding to 26 tones) can be arranged. Six tones can be used as a guard band in the leftmost band of the 20 MHz band, and five tones can be used as a guard band in the rightmost band of the 20 MHz band. In addition, seven DC tones can be inserted in the center band, i.e., the DC band, and 26 units corresponding to 13 tones can exist on each side of the DC band. In addition, 26 units, 52 units, and 106 units can be allocated to other bands. Each unit can be allocated for a receiving station, i.e., a user.

[0128] Meanwhile, the RU arrangement of FIG. 6 is utilized not only in a situation for multiple users (MUs) but also in a situation for a single user (SU), in which case it is possible to use one 242-unit as shown at the bottom of FIG. 4, in which case three DC tones can be inserted.

[0129] In the example of Fig. 6, RUs of various sizes, such as 26-RU, 52-RU, 106-RU, and 242-RU, are proposed. Since the specific sizes of these RUs can be expanded or increased, the present embodiment is not limited to the specific size of each RU (i.e., the number of corresponding tones). In this specification, N-RU may be represented as N-tone RU, etc. For example, 26-RU may be represented as 26-tone RU.

[0130] Figure 7 is a diagram showing the layout of resource units (RUs) used for 40MHz PPDU.

[0131] As in the example of Fig. 6 where RUs of various sizes were used, the example of Fig. 7 can also use 26-RU, 52-RU, 106-RU, 242-RU, 484-RU, etc. In addition, 5 DC tones can be inserted at the center frequency, 12 tones can be used as a guard band in the leftmost band of the 40 MHz band, and 11 tones can be used as a guard band in the rightmost band of the 40 MHz band.

[0132] Additionally, as illustrated, 484 RUs may be used when used for a single user. Meanwhile, the specific number of RUs may be changed, as in the example of FIG. 6.

[0133] Figure 8 is a diagram illustrating the layout of resource units (RUs) used for an 80MHz PPDU. The layout of resource units (RUs) used in this specification may vary. For example, the layout of resource units (RUs) used in the 80MHz band may vary.

[0134] Figure 9 illustrates an operation according to UL-MU. As illustrated, a transmitting STA (e.g., AP) can acquire a TXOP (925) by performing channel access through contending (i.e., backoff operation) and transmit a trigger frame (930). That is, the transmitting STA (e.g., AP) can transmit a PPDU including a trigger frame (930). When a PPDU including a trigger frame is received, a TB (trigger-based) PPDU is transmitted after a delay of SIFS.

[0135] TB PPDUs (941, 942) are transmitted at the same time and can be transmitted from multiple STAs (e.g., User STAs) whose AIDs are indicated in the Trigger frame (930). The ACK frame (950) for the TB PPDU can be implemented in various forms. For example, the ACK frame (950) for the TB PPDU can be implemented in the form of a BA (block ACK).

[0136] In FIG. 9, transmission(s) of a Trigger Frame (930), TB PPDU (941, 942) and / or ACK frame (950) can be performed within a TXOP (925).

[0137] Figure 10 shows an example of channels used / supported / defined within the 2.4 GHz band.

[0138] The 2.4 GHz band may be referred to by other names, such as the first band (band). Furthermore, the 2.4 GHz band may refer to a frequency range in which channels with a center frequency adjacent to 2.4 GHz (e.g., channels with a center frequency between 2.4 and 2.5 GHz) are used / supported / defined.

[0139] The 2.4 GHz band may include multiple 20 MHz channels. The 20 MHz within the 2.4 GHz band may have multiple channel indices (e.g., indices 1 through 14). For example, the center frequency of a 20 MHz channel assigned channel index 1 may be 2.412 GHz, the center frequency of a 20 MHz channel assigned channel index 2 may be 2.417 GHz, and the center frequency of a 20 MHz channel assigned channel index N may be (2.407 + 0.005*N) GHz. The channel indices may be referred to by various names, such as channel numbers. The specific numerical values ​​of the channel indices and center frequencies may change.

[0140] Figure 10 exemplarily illustrates four channels within the 2.4 GHz band. The illustrated first frequency region (1010) to fourth frequency region (1040) may each include one channel. For example, the first frequency region (1010) may include channel 1 (a 20 MHz channel having an index of 1). In this case, the center frequency of channel 1 may be set to 2412 MHz. The second frequency region (1020) may include channel 6. In this case, the center frequency of channel 6 may be set to 2437 MHz. The third frequency region (1030) may include channel 11. In this case, the center frequency of channel 11 may be set to 2462 MHz. The fourth frequency region (1040) may include channel 14. In this case, the center frequency of channel 14 may be set to 2484 MHz.

[0141] Figure 11 illustrates an example of channels used / supported / defined within the 5 GHz band.

[0142] The 5 GHz band may be referred to by other names, such as a second band / band, etc. The 5 GHz band may refer to a frequency range in which channels with center frequencies greater than or equal to 5 GHz and less than 6 GHz (or less than 5.9 GHz) are used / supported / defined. Alternatively, the 5 GHz band may include multiple channels between 4.5 GHz and 5.5 GHz. The specific figures shown in FIG. 11 are subject to change.

[0143] Multiple channels within the 5 GHz band include Unlicensed National Information Infrastructure (UNII)-1, UNII-2, UNII-3, and ISM. UNII-1 may be referred to as UNII Low. UNII-2 may include frequency ranges called UNII Mid and UNII-2Extended. UNII-3 may be referred to as UNII-Upper.

[0144] Within the 5 GHz band, multiple channels can be configured, and the bandwidth of each channel can be variously configured, such as 20 MHz, 40 MHz, 80 MHz, or 160 MHz. For example, the 5170 MHz to 5330 MHz frequency domain / range within UNII-1 and UNII-2 can be divided into eight 20 MHz channels. The 5170 MHz to 5330 MHz frequency domain / range can be divided into four channels through a 40 MHz frequency domain. The 5170 MHz to 5330 MHz frequency domain / range can be divided into two channels through an 80 MHz frequency domain. Alternatively, the 5170 MHz to 5330 MHz frequency domain / range can be divided into one channel through a 160 MHz frequency domain.

[0145] Figure 12 illustrates an example of channels used / supported / defined within the 6 GHz band.

[0146] The 6 GHz band may also be referred to by other names, such as the third band / band. The 6 GHz band may refer to the frequency range in which channels with center frequencies above 5.9 GHz are used, supported, or defined. The specific figures shown in Figure 12 are subject to change.

[0147] For example, the 20 MHz channel of FIG. 12 can be defined from 5.940 GHz. Specifically, the leftmost channel among the 20 MHz channels of FIG. 12 can have an index of 1 (or channel index, channel number, etc.), and a center frequency of 5.945 GHz can be assigned. That is, the center frequency of the indexed channel N can be determined as (5.940 + 0.005*N) GHz.

[0148] Accordingly, the indexes (or channel numbers) of the 20 MHz channels of FIG. 12 are 1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57, 61, 65, 69, 73, 77, 81, 85, 89, 93, 97, 101, 105, 109, 113, 117, 121, 125, 129, 133, 137, 141, 145, 149, 153, 157, 161, 165, 169, 173, 177, 181, 185, 189, 193, It can be 197, 201, 205, 209, 213, 217, 221, 225, 229, 233. Also, according to the (5.940 + 0.005*N) GHz rule mentioned above, the indices of the 40 MHz channels in Fig. 12 can be 3, 11, 19, 27, 35, 43, 51, 59, 67, 75, 83, 91, 99, 107, 115, 123, 131, 139, 147, 155, 163, 171, 179, 187, 195, 203, 211, 219, 227.

[0149] Below, the structure and types / subtypes of MAC frames are described.

[0150] Fig. 13 illustrates an example of a header of a MAC frame. As illustrated, the MAC frame may include a frame control field / information of 2 octets in length, a duration field / information of 2 octets in length, a RA (Receiver Address) field / information of 6 octets in length, and a TA (Transmitter Address) field / information of 6 octets in length. As illustrated in Fig. 13, the four fields may be consecutive to each other. The MAC header of Fig. 13 may be modified in various ways, and a new field may be inserted between the four illustrated fields, or at least one of the illustrated fields may be omitted.

[0151] The MAC header illustrated in Fig. 13 may be positioned at the very front of a MAC frame. That is, the MAC frame may include a MAC header as illustrated in Fig. 13 and MAC body fields / information subsequent to the MAC header. The MAC frame including the MAC header of Fig. 13 is inserted / included in the data field of the PPDU (e.g., UHR PPDU) illustrated in Fig. 5.

[0152] The MAC frames included in the data field of the PPDU of this specification can be classified into various types. For example, the MAC frames of this specification can be classified into control frames, management frames, and data frames.

[0153] For example, the management frame includes Association Request, Association Response, Reassociation Request, Reassociation Response, Probe Request, Probe Response, Beacon, Disassociation, Authentication, and Deauthentication frames / signals defined in conventional WLAN. For the management frame, the values ​​of the type fields (B3 and B2) in FIG. 13 are set to 00. In addition, the values ​​of the subtype fields (B7, B6, B5, B4) in FIG. 13 are as follows: Association Request (0000), Association Response (0001), Reassociation Request (0010), Reassociation Response (0011), Probe Request (0100), Probe Response (0101), Beacon (1000), Disassociation (1010), Authentication (1011), Deauthentication (1100).

[0154] For example, the control frame includes Trigger Beamforming Report Poll, NDP Announcement (NDPA), Control Frame Extension, Control Wrapper, Block Ack Request (BlockAckReq), Block Ack (BlockAck), PS-Poll, RTS, CTS, Ack, and CF-End frames / signals defined in conventional WLAN. For the control frame, the value of the type field (B3 and B2) in FIG. 13 is set to 01. Also, the values ​​of the subtype fields (B7, B6, B5, B4) of FIG. 13 are as follows: Trigger (0010), Beamforming Report Poll (0100), NDP Announcement (0101), Control Frame Extension (0110), Control Wrapper (0111), BlockAckReq (1000), BlockAck (1001), PS-Poll (1010), RTS (1011), CTS (1100), Ack (1101), CF-End (1110).

[0155] For example, the data frame includes (QoS) Data, (QoS) Null, etc. defined in conventional WLAN. For the management frame, the value of the type field (B3 and B2) of Fig. 13 is set to 10.

[0156] The MAC frame / signal used in this specification can be identified through the type field / information and subtype field / information described above. For example, the "trigger frame" in this specification can mean a MAC frame in which the type bits B3 and B2 bits in the frame control field of the MAC header are set to 01, and the subtype bits B7, B6, B5, B4 bits in the frame control field are also set to 0010. Various MAC frames described in this specification are inserted / included in the data fields of various PPDUs (e.g., HE / VHT / HE / EHT / UHR PPDUs).

[0157] FIG. 14 illustrates a modified example of a transmitting device and / or a receiving device of the present specification.

[0158] The devices (e.g., AP STA, non-AP STA) illustrated in FIGS. 1 to 4 may be modified as illustrated in FIG. 14. The transceiver (630) of FIG. 14 may be identical to the transceivers (113, 123) of FIG. 1. The transceiver (630) of FIG. 14 may include a receiver and a transmitter.

[0159] The processor (610) of FIG. 14 may be identical to the processor (111, 121) of FIG. 1. Alternatively, the processor (610) of FIG. 14 may be identical to the processing chip (114, 124) of FIG. 1.

[0160] The memory (150) of FIG. 14 may be the same as the memory (112, 122) of FIG. 1. Alternatively, the memory (150) of FIG. 14 may be a separate external memory different from the memory (112, 122) of FIG. 1.

[0161] Referring to FIG. 14, a power management module (611) manages power to a processor (610) and / or a transceiver (630). A battery (612) supplies power to the power management module (611). A display (613) outputs results processed by the processor (610). A keypad (614) receives input to be used by the processor (610). The keypad (614) may be displayed on the display (613). A SIM card (615) may be an integrated circuit used to securely store an international mobile subscriber identity (IMSI) and an associated key used to identify and authenticate a subscriber in a mobile phone device, such as a mobile phone or computer.

[0162] Referring to FIG. 14, the speaker (640) can output sound-related results processed by the processor (610). The microphone (641) can receive sound-related input to be used by the processor (610).

[0163] Figure 15 illustrates an example of a network allocation vector (NAV) setting. The example in Figure 15 relates to the exchange of RTS (Ready To Send) frames and CTS (Clear To Send) frames. Figure 15 relates to an example in which a NAV is set based on an RTS / CTS exchange.

[0164] Referring to Figure 15, the Source STA transmits an RTS frame, and the Destination transmits a CTS frame. As described above, the destination STA designated as the receiver through the RTS frame does not set a NAV. Some of the remaining STAs may receive the RTS frame and set a NAV, and others may receive the CTS frame and set a NAV.

[0165] If a CTS frame (e.g., PHY-RXSTART.indication primitive) is not received within a certain period from the time when the RTS frame is received (e.g., the time when the MAC receives the PHY-RXEND.indication primitive corresponding to the RTS frame), STAs that have set or updated the NAV through the RTS frame may reset the NAV (e.g., 0). The certain period may be (2*aSIFSTime + CTS_Time + aRxPHYStartDelay + 2*aSlotTime). The CTS_Time may be calculated based on the length of the CTS frame and the data rate indicated by the RTS frame.

[0166] In Fig. 15, for convenience, setting or updating NAV through RTS frame or CTS frame is illustrated, but NAV setting / resetting / updating can be performed based on a duration field (e.g., duration field in MAC header of MAC frame) included in one PPDU based on various other frames, for example, non-HT PPDU, HT PPDU, VHT PPDU, HE PPDU, EHT PPDU, and / or UHR PPDU. For example, if the RA field in the received MAC frame does not match its own address (e.g., MAC address), the STA can set / reset / update NAV.

[0167] The Source STA of FIG. 15 may be modified in various ways. For example, the Source STA of FIG. 15 may be a non-AP STA or an AP. Additionally or alternatively, the Source STA of FIG. 15 may be at least one non-AP STA included in a non-AP MLD, or at least one AP included in an AP MLD. Additionally or alternatively, the Source STA of FIG. 15 may be various STAs, such as STA 1, STA 2, AP 1, and AP 2, as described below.

[0168] Below, primary channels, secondary channels, channel extension / bonding, etc. are explained.

[0169] For example, in an IEEE 802.11n system, two 20MHz channels can be combined to perform 40MHz channel extension / bonding. Additionally, in an IEEE 802.11ac system, 40 / 80 / 160MHz channel extension / bonding can be performed.

[0170] For example, an STA can perform channel extension / bonding for a Primary 20 MHz channel (or P20 channel) and a Secondary 20 MHz channel (S20 channel). For channel extension / bonding, a backoff count / counter can be used. The backoff count value can be randomly selected and decremented during the backoff interval. Typically, when the backoff count value becomes 0, an STA (e.g., a non-AP STA or AP) can attempt to connect to the channel.

[0171] An STA performing channel extension / bonding determines whether the S20 channel has been in the Idle state for a certain period of time (e.g., point coordination function interframe space (PIFS)) when the P20 channel is determined to be in the Idle state during the backoff interval and the backoff count value for the P20 channel becomes 0. If the S20 channel is in the Idle state, the STA can perform bonding for the P20 channel and the S20 channel. That is, the STA can transmit a signal (e.g., PPDU) through a 40 MHz channel including the P20 channel and the S20 channel (i.e., a 40 MHz bonding channel).

[0172] Figure 16 illustrates an example related to a primary channel, a secondary channel, and channel extension / bonding. As illustrated in Figure 16, a primary 20 MHz channel and a secondary 20 MHz channel can form a 40 MHz channel (primary 40 MHz channel) through channel extension / bonding. That is, an extended / bonded 40 MHz channel can include a primary 20 MHz channel and a secondary 20 MHz channel.

[0173] The positions of the channels (e.g., P20 / S20 / S40 / S80 channels) shown in Fig. 16 can be varied in the frequency domain.

[0174] According to the prior art, channel expansion / bonding can be performed when a channel consecutive to a primary channel is in an idle state. That is, a primary 20 MHz channel (or P20 channel), a secondary 20 MHz channel (or S20 channel), a secondary 40 MHz channel (or S40 channel), and a secondary 80 MHz channel (or S40 channel) can be sequentially expanded / bonded. However, if the secondary 20 MHz channel (or S20 channel) is determined to be busy, channel expansion / bonding may not be performed even if all other secondary channels are in an idle state. In addition, if the secondary 20 MHz channel (or S20 channel) is determined to be idle and the secondary 40 MHz channel is determined to be busy, channel expansion / bonding can be performed only for the primary 20 MHz channel (or P20 channel) and the secondary 20 MHz channel (or S20 channel).

[0175] For example, in a wireless LAN system (e.g., 802.11 system), Channel Access can be performed based on the Primary channel (e.g., P20 channel). For example, as described above, an STA can transmit a frame (e.g., 40 MHz PPDU) including an IDLE Secondary channel (e.g., S20 channel) when the Primary channel (e.g., P20 channel) is IDLE and the Back-off counter (BC) is 0. For this purpose, it is desirable for all STAs to perform CCA on the Primary channel (e.g., P20 channel).

[0176] Therefore, the AP can announce the BSS's Primary channel (e.g., P20 channel). For example, information related to the Primary channel can always be included in Management frames transmitted by the AP, such as Beacon and Probe Response frames. This mechanism is effective for ensuring interference-free frame exchange between all STAs and the AP (or for adequate medium protection). However, if only the primary channel (e.g., P20 channel) is BUSY and the surrounding secondary channels are IDLE, the STA can access the IDLE secondary channel. Consequently, there is a technical characteristic that may reduce efficiency from a medium utilization perspective.

[0177] Figure 17 relates to an example of channel access related to an 80 MHz channel. For example, Figure 17 relates to channel access based on a primary channel defined on a wireless medium having an 80 MHz bandwidth. The three channels / subchannels illustrated in Figure 17 are denoted as P20, S20, S40, etc., and the related terminology can be explained as follows.

[0178] P20: Primary 20MHz Channel

[0179] S20: Secondary 20MHz Channel

[0180] S40: Secondary 40MHz Channel

[0181] S80: Secondary 80MHz Channel

[0182] S160: Secondary 160MHz Channel

[0183] The above-described P20, S20, S40, S80, and S160 can correspond to each channel / subchannel shown in Fig. 16.

[0184] For example, if the CCA result for P20 (channel) is determined to be BUSY, or if NAV (as described in FIG. 15) is set for P20 and determined to be BUSY, the BC for P20 is not decreased. In this case, the BC may not be decreased until P20 becomes IDLE. When the BC becomes 0 through this back-off process (e.g., BC decrease process), the STA can check the channel states of S20 (channel) and S40 (channel) (e.g., check based on the CCA technique). In addition, the STA can transmit a frame through the extended channel / resource according to the check result. In the example of FIG. 17, since S40 (channel) is BUSY, a frame corresponding to a 40MHz PPDU is transmitted through P20 and S20. In other words, the example of FIG. 17 relates to an example in which a 40 MHz channel including a P20 channel and an S20 channel is configured through the channel expansion / bonding described above.

[0185] As in the example of Fig. 17, when P20 is determined to be BUSY and S20 and S40 are determined to be IDLE, an STA operating according to a conventional access technique wastes a bandwidth equivalent to 60 MHz. Consequently, the efficiency of medium usage decreases. The example of this specification proposes various techniques / methods / devices to improve this. For example, the example of this specification proposes various techniques / methods / devices that enable access to a secondary channel (or non-primary channel) even when P20 is BUSY.

[0186] The various examples below are preferably applied to STAs of a wireless LAN system. For example, the STAs (or STA1 to STA#N, etc.) below may be at least one non-AP STA (included in a non-AP MLD) or at least one AP (included in an AP MLD).

[0187] This specification relates to an operation for performing Access to a Secondary Channel (e.g., S20). Access to a Secondary Channel may be expressed as Secondary Channel Access (SCA). When an SCA is initiated / performed / triggered, an STA may switch to a Secondary Channel (e.g., S20) and subsequently perform CCA sensing (and / or backoff counter decrement) on the switched Secondary Channel.

[0188] The term "SCA" can be variously modified. For example, "SCA" can have the same meaning as "Non-Primary Channel Access" (NPCA). For example, in the examples below, the term "SCA" can be replaced with the term "NPCA." For example, in the examples below, the term "SCA mode" can be replaced with the term "NPCA mode." Furthermore, in the examples below, the term "SCA enabled presence" can be replaced with the term "NPCA enabled presence."

[0189] Additionally or alternatively, the term "Secondary Channel" may be variously modified. For example, the secondary 20MHz channel described above may also be called an NPCA primary channel, as it is where the primary SCA / NPCA operations are performed by STAs (e.g., by APs / non-AP STAs).

[0190] Below is information related to Capabilities for Secondary Channel Access.

[0191] For example, Capabilities for SCA (or NPCA) can be defined / exchanged / negotiated in advance. For example, non-AP STAs and APs can inform each other of the defined / exchanged / negotiated information. For example, Capabilities for SCA (or NPCA) can be related to CCA (e.g., an operation based on conventional preamble detection (PD)) that can identify Wi-Fi frames performed on a primary channel (e.g., the P20 channel described above). For example, as in the specific example below, Capabilities for SCA (or NPCA) can include information on whether frames can be decoded on the SCH (or the S20 channel or the NPCA primary channel). Through these Capabilities for SCA / NPCA, additional NAV(s) (e.g., at least one Intra-BSS NAV and / or Basic NAV) can be set on the SCH (or the NPCA primary channel).

[0192] For example, Capabilities for SCA (or NPCA) can be configured based on 2-bit information. For example, Level 0 / 1 / 2 as shown below can be identified through the first / second / third values ​​of the 2-bit information. The length of the 2-bit information can be varied. Accordingly, the 2-bit information can also be configured through 3 / 4 / 5 bits, etc. Not all of Level 0 / 1 / 2 below must be used, and at least one can be selectively used.

[0193] The three specific levels of Capabilities for the above-mentioned SCA (or NPCA) are explained below.

[0194] Level 0: For example, Level 0 may mean "No Back-off on SCH." For example, when the above level is set, CCA as before may be performed on the SCH (by the STA). In this case, CCA capable of detecting a Wi-Fi signal (e.g., referred to as guard interval detection (GID)) and / or CCA capable of detecting a signal above a certain strength (e.g., referred to as energy detection (ED)) may be performed.

[0195] Level 1: For example, Level 1 may mean "Back-off on a SCH at a time." For example, when this level is set, PD can only be performed on one secondary channel at a time.

[0196] Level 2: For example, Level 2 may mean "Back-off on SCHs at the same time." For example, when this level is set, PD can be performed on multiple secondary channels simultaneously.

[0197] For example, the Capabilities described above may be included in various management frames, such as Beacon, Probe Response frame, (Re)Association Request frame, etc., generated / transmitted by the AP, including UHR capabilities IE, etc. Additionally or alternatively, the Capabilities described above may be included in various management frames, such as Probe Request frame, (Re)Association Request frame, etc., generated / transmitted by non-AP STAs.

[0198] The NAV described in Fig. 15 can be distinguished into Intra-BSS NAV and Basic NAV. Intra-BSS NAV may be a NAV set by Intra-BSS frame / PPDU, and Basic NAV may be a NAV set by OBSS (overlapping BSS) frame / PPDU.

[0199] For example, if an Intra-BSS NAV is set for the PCH by an STA (e.g., a non-AP STA or an AP), SCA (or NPCA) may not be performed. For example, when an AP exchanges frames with an STA (e.g., a non-AP STA) within the TXOP it acquired, the other STA may set an intra-BSS NAV based on the primary channel. At this time, the STA that set the intra-BSS NAV can transmit the frame to the AP after accessing the SCH, and in this case, if the AP is performing Tx (e.g., DL Data, Ack, etc.), the AP will not receive the related signal. Accordingly, it is desirable for the STA to initiate / trigger SCA only when the Basic NAV is set on the PCH.

[0200] The above technical characteristic can be expressed in various ways. For example, the above technical characteristic can be expressed as: an STA (e.g., a non-AP STA or AP) can perform SCA when Basic NAV is configured on the PCH.

[0201] Figure 18 illustrates an example of an SCA process. The example of Figure 18 (e.g., SCA / NPCA operation) can be performed by STA1 (e.g., an AP or non-AP STA). As illustrated, if a Basic NAV is set while performing a back-off on the P20 channel, the back-off can be performed on the S20 channel (or NPCA primary channel) at the time the Basic NAV is set. In this case, the back-off on the S20 channel (or NPCA primary channel) may be performed after a delay from the time the Basic NAV is set, rather than immediately after the time the Basic NAV is set. For example, a switching delay may occur to perform PD from the P20 channel to the S20 channel. The above example differs from the CCA method in that CCA can be performed on the S20 channel, and can be performed at all levels. The reason why back-off is performed on the S20 channel (or NPCA primary channel) is that if a neighboring STA with the same or similar operation channel as STA 1 does not perform back-off and is IDLE, frames can be transmitted simultaneously. In this case, a collision may occur, which may result in channel waste.

[0202] SCA / NPCA can be performed based on the following technical features:

[0203] First, here is an example of setting TXOP on the secondary channel (or NPCA primary channel):

[0204] For example, when the Basic NAV on the P20 channel expires, a CCA may need to be performed on the P20 channel. Accordingly, it is desirable that the end time of the TXOP for the secondary channel (e.g., the S20 channel or the NPCA primary channel) be set to end before the time when the Basic NAV on the primary channel (e.g., the P20 channel) expires.

[0205] Additionally or alternatively, if there is not enough time to set up the TXOP of the secondary channel, the Frame may not be transmitted (on the secondary channel).

[0206] For example, if the end time of the TXOP of the secondary channel is set to end after the time when the Basic NAV (of the primary channel) expires, a problem may occur in which STA1 of FIG. 18 cannot receive the frame because Legacy STAs, etc. may transmit the frame through the P20 channel. In addition, if the TBTT is set in the middle of the Basic NAV, a problem may occur because STA1 of FIG. 18 must prepare to transmit the Beacon immediately after the Basic NAV.

[0207] Secondly, an example of transmitting a Frame on a secondary channel (e.g., at least one channel including an NPCA primary channel) is described.

[0208] Previously, the P20 channel had to be determined to be IDLE, and then preamble puncturing could be performed based on the IDLE / BUSY determination of at least one SCH channel. For the SCA / NPCA of this specification, since the P20 channel is considered to be BUSY, the rule for this can be changed as follows. For example, if the P20 channel is determined to be BUSY, the P20 channel can be punctured, and other BUSY SCH(s) based on the S20 channel can also be punctured, and as a result, a frame can be transmitted through the IDLE SCH(s). For example, in the example of FIG. 18, all three 20MHz channels included in the S20 and S40 channels are determined to be IDLE. Accordingly, STA1 can transmit an 80MHz PPDU (including a MAC frame) while performing preamble puncturing on the P20 channel of the 80MHz PPDU. That is, the U-SIG field of the 80 MHz PPDU may include information indicating puncturing of the P20 channel.

[0209] Below, various technical features of the SCA / NPCA mode are described.

[0210] For example, if an STA (AP or non-AP STA) has capabilities for SCA / NPCA and the STA must switch to the S20 channel (or NPCA primary channel) to perform SCA / NPCA when Basic NAV is set on the P20 channel, the following issues may occur:

[0211] For example, if the BSS Operating channel of an AP (MLD) and the BSS Operating channels of neighboring APs (i.e., APs that are OBSS) overlap, they may affect each other during SCA / NPCA. Specifically, when an AP succeeds in SCA and uses all SCHs, if the PCHs of other APs overlap, the channel access opportunities may be reduced. For example, if STA1 of FIG. 18 is AP 1 of FIG. 22 and / or FIG. 23, AP 2 may not be able to use P20 and S20, etc. because S20 (channel) of AP 1 is P20 (channel) of AP 2. In this case, when AP 1 performs SCA, a problem may occur in that the other AP 2 (not shown) does not have many channel access opportunities based on the existing PCH. In addition, when one AP has capabilities for SCA but another AP does not have capabilities for SCA, the time that the AP with SCA capabilities occupies the channel may be prolonged, which may reduce fairness.

[0212] In addition, if all STAs associated with an AP that has SCA capabilities (or NPCA capabilities) do not have SCA capabilities, the AP may perform SCA / NPCA. In this case, the AP may not need to perform SCA since it may not be able to successfully exchange frames with all STAs. Additionally or alternatively, if the AP does not have SCA capabilities, the STAs associated with the AP may not need to perform SCA even if they have SCA capabilities. Additionally or alternatively, at least one STA may not want to perform SCA for power saving even if it has SCA capabilities. As described above, if it is defined as an optional feature that STAs perform SCA / NPCA by switching to the S20 channel (or NPCA primary channel) when the Basic NAV is set in the PCH, it may be impossible for STAs and APs to determine whether each other performs SCA when the Basic NAV is set. As a result, normal frame exchange between APs and STAs may not be possible. Therefore, it is desirable for STAs (e.g., APs and / or STAs) with SCA capabilities to indicate whether or not to perform SCA / NPCA based on the surrounding circumstances and their own intentions. Furthermore, through such indications, STAs may choose not to perform SCA for the purpose of power saving even if they have SCA capabilities. Furthermore, APs may choose not to perform SCA to ensure fairness in PCH-based transmissions of OBSS.

[0213] For example, an STA (e.g., an AP and / or a non-AP STA) may include at least one of the following information regarding Secondary Channel Access Operation. For example, the following information (e.g., information related to Secondary Channel Access Capability, Secondary Channel Access Mode, and / or SCA Disabled Count, as described below) may be included in the (UHR) Operation IE or in a new IE form in the Management frame including the AP's Beacon, (Multi-link) Probe Response, and (Re)Association Response. Additionally or alternatively, the following information may be included in the (UHR) Operation IE or in a new IE form in the Management frame including the (Multi-link) Probe Request, (Re)Association Request of a non-AP STA. Additionally or alternatively, the following information may be conveyed via the multi-link element or the Reduced Neighbor Report element of the Beacon frame. Additionally or alternatively, the following information may be conveyed in the multi-link element of the Multi-link Probe Response frame.

[0214] Secondary Channel Access (SCA) Capability

[0215] Below, information related to Secondary Channel Access Capability is described. As described above, since the term Secondary Channel Access can be replaced with NPCA, the information may be referred to by various names, such as SCA capability field / information / subfield / bit, etc., or NPCA capability field / information / subfield / bit.

[0216] The above-described SCA Capability field / information / subfield / bit contains information about whether an STA (e.g., a UHR non-AP STA or a UHR AP) has the capability to perform SCA.

[0217] For example, the information described above may have various bit lengths. For example, if it is configured based on 1 bit, a value of “1” (or a value of “0”) may mean that the corresponding STA has SCA capability, and a value of “0” (or a value of “1”) may mean that the corresponding STA does not have SCA capability.

[0218] Secondary Channel Access (SCA) Mode:

[0219] Below, information related to the SCA mode is described. As described above, since the term Secondary Channel Access can be replaced with NPCA, the information may be called SCA mode field / information / subfield / bit, etc., or various other names such as NPCA mode field / information / subfield / bit.

[0220] When the above SCA Capability field is set to 1, that is, when Basic NAV is set in the PCH by an STA (e.g., a non-AP STA or AP) having SCA capability, it can be indicated whether to perform SCA / NPCA by switching to the SCH (or NPCA primary channel).

[0221] For example, if the SCA mode information is configured based on 1 bit, a first value (e.g., a value of “1”) may indicate that SCA is performed, and a second value (e.g., a value of “0”) may indicate that SCA is not performed. Additionally or alternatively, if the SCA mode is indicated by the first value, the SCA mode may be expressed as enabled. Additionally or alternatively, if the SCA mode is indicated by the second value, the SCA mode may be expressed as disabled.

[0222] Additionally or alternatively, an STA (e.g., a non-AP STA or AP) with SCA Capability 1, i.e., equipped / supporting SCA Capability, may always indicate a value related to the SCA Mode information.

[0223] Example_1: The following is an explanation of a case where an AP with SCA Capability set to 1 announces with SCA Mode set to 0.

[0224] Example_1-1: STAs associated with an AP (e.g., at least one non-AP STA) can notify the AP of their SCA Mode field according to their intention. In this case, regardless of the SCA Mode, it is possible to prevent unnecessary SCA execution by non-AP STAs and the AP without switching to the SCH (in any case, non-AP STAs with the SCA Mode set to 1 will know that the AP has not switched even if they do).

[0225] Example_1-2: An STA associated with an AP (e.g., at least one non-AP STA) can set its SCA Mode field to 0, the same as the AP.

[0226] Example_1-2-1: STAs associated with an AP (e.g., at least one non-AP STA) maintain SCA Mode 0 until the AP announces SCA Mode 1 again, and when the AP announces SCA Mode 1, they can return to the SCA Mode set by the original non-AP STA.

[0227] Example_1-2-2: When the AP announces SCA Mode as 1 again, all STAs (e.g., all non-AP STAs) can indicate their SCA Mode through the SCA Mode Notification frame.

[0228] Example_2: The following is an explanation of a case where an AP with the SCA Capability set to 1 announces by setting the corresponding field to 1.

[0229] Each STA (e.g., non-AP STA) indicates this by setting its SCA Mode field to 0 or 1. The AP does not perform SCA with STAs that set the SCA Mode to 0 (e.g., non-AP STAs), but can exchange frames through SCA with STAs that set the SCA Mode to 1 (e.g., non-AP STAs).

[0230] Example_2-1: An AP may maintain its SCA Mode but not switch to the SCH (or NPCA primary channel). This is because it knows that all STAs (e.g., non-AP STAs) currently have their SCA Mode set to 0, and no STAs are capable of performing SCA.

[0231] Example_2-2: If all STAs (e.g., all non-AP STAs) set SCA Mode to 0, the AP can change its SCA Mode to 0.

[0232] Example_2-2-1: If one or more STAs (e.g., non-AP STAs) update their SCA Mode to 1 to indicate this, the AP can set its SCA Mode back to 1 and perform SCA with those STAs.

[0233] Additionally or alternatively, an AP with SCA capability can always enable SCA Mode without the aforementioned Example_1 process where the AP announces the SCA Mode. In this case, only STAs (e.g., non-AP STAs) indicate their SCA Mode, so that the AP can perform SCA if there are any enabled STAs (e.g., non-PA STAs). In this case, if all STAs (e.g., non-AP STAs) are disabled, the AP may not perform SCA.

[0234] The AP may transmit the information described above in the Management frame, including Beacon, Probe Response, and Association Response, within the UHR Operation IE or in the form of a new IE.

[0235] Additionally or alternatively, only SCA Capability can be exchanged between an AP and a STA (e.g., a non-AP STA) in Beacon, Probe request / response, and Association Request / Response. In this case, the STA associated with the AP (e.g., a non-AP STA), and the AP may initially be connected with the SCA Mode disabled by default. In this case, if the AP or STA (e.g., a non-AP STA) wants to change the SCA Mode, the AP or STA may set the SCA Mode value to the first value (e.g., the first value corresponding to the enable mode) in the SCA Mode Notification frame and transmit it to the AP or STA (e.g., a non-AP STA).

[0236] Additionally or alternatively, only SCA Capability can be exchanged between an AP and a STA in Beacon, Probe request / response, and Association Request / Response. In this case, the STA associated with the AP (e.g., a non-AP STA), and the AP can be initially connected with SCA Mode enabled by default. In this case, if the AP or STA (e.g., a non-AP STA) wants to change the SCA Mode, the AP or STA can set the SCA Mode value to a second value (e.g., a second value corresponding to the disable mode) in the SCA Mode Notification frame and transmit it to the AP or STA (e.g., a non-AP STA).

[0237] For example, the AP can determine whether to not perform SCA for an STA (e.g., a non-AP STA) that indicates the SCA Mode as a second value (e.g., a second value corresponding to the disable mode). In this case, the AP may not transmit a frame through SCA to the STA, but may transmit a frame to the STA that sets the SCA Mode to the first value (e.g., a first value corresponding to the enable mode). For example, the STA (e.g., a non-AP STA) may include the information in a new IE format in the Management frame including the STA's Probe Request and (Re) Association Request.

[0238] Additionally or alternatively, APs and STAs (e.g., non-APs) that wish to change their SCA Mode after the Association process can do so via the SCA Mode Notification frame as follows. For example, the AP may announce the SCA Mode value to the first value (e.g., 1 corresponding to enable) via a beacon. In this case, a specific STA may transmit an Association Request frame indicating whether or not it does not perform SCA for the purpose of power saving (e.g., whether SCA Mode = 0). In this case, the STA (e.g., non-AP STA) does not perform SCA, and the AP, upon recognizing this, may not transmit the frame to the STA when performing SCA. After this, the STA (e.g., non-AP STA) may want to perform SCA and may transmit the changed / updated SCA Mode to the AP by setting the SCA Mode value to the first value (e.g., 1 corresponding to enable) in the SCA Mode Notification frame. In this case, since the AP is also enabled, they can communicate that they will perform SCA with each other.

[0239] For example, the SCA Mode Notification frame may be renamed to various names. For example, various names such as NDPCA mode Notification frame, Mode Notification frame, Node update / change frame, etc. may be used.

[0240] -SCA Disabled Count:

[0241] Below, information related to the SCA Disabled Count is described. As described above, since the term Secondary Channel Access can be replaced with NPCA, the information may be called SCA Disabled Count field / information / subfield / bit, etc., or various other names such as NPCA Disabled Count field / information / subfield / bit.

[0242] When indicating that SCA is not to be performed (e.g., a value of 0 indicating the disable mode is set), the information related to the SCA Disabled Count may indicate that SCA will be re-enabled after the TBTT specified in the field. For example, the field may be indicated only when the SCA Mode is set to 0.

[0243] Additionally or alternatively, information related to the SCA Disabled Count may be indicated in units of microseconds. Additionally or alternatively, information related to the SCA Disabled Count may be indicated in units of units (TU). Additionally or alternatively, information related to the SCA Disabled Count may be indicated based on the TSF.

[0244] For example, if the information related to the SCA Disabled Count is configured based on 8 bits, if the bit value is 0, it may mean that the SCA Mode will be maintained as 0 until it indicates whether to enable / disable itself through the SCA Mode Notification frame regardless of time. For example, if the bit value is 1, it may mean that the SCA Mode value is set to 1 after 1 TBTT. Additionally or alternatively, the STA may set the value related to the SCA Disabled Count to reflect interference due to in-device coexistence of non-WiFi STAs.

[0245] For example, an STA can detect interference due to periodic (or aperiodic) non-WiFi STA traffic on the PCH. In this case, the STA (e.g., non-AP STA or AP) can perform SCA by switching to the SCH while the PCH is unavailable due to the interference. In addition, the STA can notify neighboring STAs (e.g., non-AP STA or AP) of unavailable time information (start time / end time / period / duration) on the PCH and / or information related to the band / frequency resource / channel / subchannel where interference occurs.

[0246] For example, a mobile AP may experience PCH unavailability due to traffic from non-WiFi STAs. In this case, the mobile AP can broadcast information regarding the time of unavailability and / or the band / frequency resource / channel / subchannel where interference occurs. Upon receiving this, the non-AP STA can switch to the SCH during the unavailable time and perform SCA with the mobile AP.

[0247] Based on this information, it can be determined that the band / frequency resource / channel / subchannel occupied by the non-WiFi STA is included in the SCA Channels set by the AP. For example, in this case, the AP with the SCA Mode enabled can change its SCA Mode to disabled and announce the SCA Disabled Count value by reflecting the time during the period when there is interference from the non-WiFi STA. The STA that receives this (e.g., the non-AP STA) can determine that during the period, the AP did not switch to the SCH and frame transmission and reception are impossible due to the traffic of the non-WiFi STAs. For example, from the STA's perspective, it can prevent the STA from performing a back-off by switching to an unnecessary SCH.

[0248] Additionally or alternatively, 11bn may define a new Action frame (which may be referred to by various terms, e.g., SCA Mode Notification frame). For example, after Association, the AP and STA (e.g., non-AP STA) may transmit the corresponding information in an SCA Mode Notification frame.

[0249] This specification proposes an example of providing various information regarding the aforementioned SCA / NPCA at the MLD level. For example, the various information proposed in this specification may be organized at the MLD level, rather than at the level of a single link (or a single non-AP STA or AP).

[0250] The first method related to information composed of MLD-level is as follows.

[0251] Method 1

[0252] Figures 19 and 20 illustrate examples related to the first method. The first method relates to the SCA Mode Link Bitmap. For example, the SCA Mode Link Bitmap may have a length of up to 16 bits.

[0253] For example, AP MLD and Non-AP MLD can transmit information related to one link (e.g., at least one first link) to another link (e.g., at least one second link) through the Multi-link element. By utilizing this, each AP affiliated with AP MLD and each STA affiliated with Non-AP MLD can be enabled or disabled for each link through the corresponding bitmap and the SCA Mode subfield defined above. For example, as shown in FIG. 19, three links between AP MLD and non-AP MLD are connected, and the Link ID of the first link may be 0, the Link ID of the second link may be 1, and the Link ID of the third link may be 2. For example, in this case, if AP MLD wants to enable SCA Mode for the links for Link ID 0 and Link ID 1, AP MLD sets the SCA Mode value in Beacon to 1 and sets the bit corresponding to the corresponding link to 1. In the example of Fig. 19, the SCA Mode Link Bitmap may have a length of 3 bits. In the example of Fig. 19, the bitmap may be set to 110. The Non-AP MLD that receives this may inform the AP MLD of information about the SCA Mode for each affiliated STA (e.g., information related to enable or disable). In this method, the operation for the SCA Mode described above may be performed for each affiliated STA or each affiliated AP (based on per link). Through this, it can be confirmed that AP 1 and STA 1 illustrated in Fig. 20 perform SCA when Basic NAV is set in the PCH (e.g., P20 channel illustrated in Fig. 20).

[0254] Additionally or alternatively, the examples of FIGS. 19 and 20 may be expressed differently as follows. An example of the present specification relates to an operation between a first MLD and a second MLD. For example, an example of the first MLD may be an AP MLD of FIG. 19. An example of the second MLD may be a non-AP MLD of FIG. 19. For example, the first MLD may perform a multi-link operation related to a plurality of links (e.g., Link 1, Link 2, Link 3, etc. as shown in FIG. 19). For example, the first MLD may include affiliated STAs, and the affiliated STAs may be a plurality of STAs (e.g., AP 1, AP 2, AP 3 as shown in FIG. 19). For example, the second MLD may perform a multi-link operation related to a plurality of links (e.g., Link 1, Link 2, Link 3, etc. as shown in FIG. 19). For example, the second MLD may include affiliated STAs, and the affiliated STAs may be a plurality of STAs (e.g., Non-AP STA 1, Non-AP STA 2, Non-AP STA AP 3 as illustrated in FIG. 19). A first STA according to the present specification (e.g., AP 1 as illustrated in FIG. 20) may transmit a first management frame (e.g., Beacon as illustrated in FIG. 20) to a second STA (e.g., STA 1 as illustrated in FIG. 20) based on a first link (e.g., Link 1 as illustrated in FIG. 19). For example, the first management frame (e.g., Beacon as illustrated in FIG. 20) may include first bitmap information (e.g., SCA Mode Link Bitmap as illustrated in FIG. 20) related to an NPCA mode performed by the first MLD for the plurality of links. For example, the first STA (eg, AP1 shown in FIG. 20) may be connected to the first link (eg, based on the Link 1) illustrated in FIG. 19, a second management frame (e.g., Association REQ frame illustrated in FIG. 20) may be received from the second STA (e.g., STA 1 illustrated in FIG. 20). For example, the first bitmap information (e.g., SCA Mode Link Bitmap illustrated in FIG. 20) may have a length of 16 bits. For example, one bit of the first bitmap may indicate whether the first MLD performs NPCA on one link corresponding to the one bit. Accordingly, in the example of FIG. 20, the 110 bitmap may indicate an enabled mode for a first link, an enabled mode for a second link, and a disabled mode for a third link. For example, the first management frame (e.g., Beacon as shown in FIG. 20) may further include first NPCA mode information (e.g., SCA Mode: 1 (enabled) as shown in FIG. 20) related to the NPCA mode of the first STA (e.g., AP 1 as shown in FIG. 20). For example, the first NPCA mode information (e.g., SCA Mode: 1 (enabled) as shown in FIG. 20) may be set to a first value (e.g., “1” as shown in FIG. 20) based on the NPCA mode of the first STA being enabled. For example, after the first management frame (e.g., Beacon as shown in FIG. 20) and the second management frame (e.g., Association REQ frame as shown in FIG. 20) are exchanged, NPCA / SCA by the first STA (e.g., AP 1 as shown in FIG. 20) may be performed. For example, the first STA sets the NPCA primary channel (e.g., based on the Basic NAV being set for the Primary Channel of the first link), performs a switch to the S20 channel or the SCH for back-off of FIG. 20). For example, the Basic NAV may be set by an OBSS PPDU received by the first STA (eg, AP 1 of FIG. 20). After the first STA performs the NPCA primary channel switching, the first STA may obtain a TXOP for the NPCA primary channel based on performing back-off on the NPCA primary channel. For example, based on the obtained TXOP, the first STA may transmit a frame (eg, Control frame to STA 1 of FIG. 20) based on the NPCA primary channel (and at least one SCH / NPCA channel based on channel extension) to a second STA (eg, STA 1 of FIG. 20).

[0255] As illustrated in FIGS. 19 and 20 , the first method described above can indicate the same SCA Mode for multiple links. The methods illustrated in FIGS. 19 and 20 can be improved in various ways. For example, an additional second method for cases where the Non-AP MLD is to be disabled for STA2 and enabled for STA3 is proposed through FIGS. 21 to 23 . For example, the second method can be proposed with respect to information configured at the MLD level.

[0256] Figures 21 to 23 illustrate examples related to the second method.

[0257] The second method described below can be performed based on various information / bits / subfields / fields proposed below.

[0258] SCA Enabled Presence (eg, 1 bit)

[0259] Below, information related to SCA Enabled Presence is described. As mentioned above, since the term SCA can be replaced with NPCA, the information can be called SCA Enabled Presence field / information / subfield / bit, etc., or various other names such as NPCA Enabled Presence field / information / subfield / bit.

[0260] The information related to the above SCA Enabled Presence can be composed of bits of various lengths, and can be composed of fields / information / subfields having a length of, for example, 1 bit. For example, if the value is set to the first value (or 1), it can mean the presence of the Enabled link bitmap field / information / subfield / bit described below. For example, the first value can indicate that the SCA Mode is enabled for a specific link according to the Enabled link bitmap described below. For example, if the value is set to the second value (or 0), it means that the Enabled link bitmap does not exist.

[0261] SCA Disabled Presence (eg, 1 bit)

[0262] Below, information related to SCA Disabled Presence is described. As mentioned above, since the term SCA can be replaced with NPCA, the information can be called SCA Disabled Presence field / information / subfield / bit, etc., or various other names such as NPCA Disabled Presence field / information / subfield / bit.

[0263] The information related to the above SCA Disabled Presence can be composed of bits of various lengths, and can be composed of fields / information / subfields having a length of, for example, 1 bit. For example, if the corresponding value is set to the first value (or 1), it can mean the presence of the Disabled link bitmap field / information / subfield / bit described below. For example, the first value indicates that the SCA Mode is disabled for a specific link according to the Disabled link bitmap. For example, if the corresponding value is set to the second value (or 0), it means that the Disabled link bitmap does not exist.

[0264] Enabled link bitmap (0 or 16 bits)

[0265] Below, information related to the Enabled link bitmap is described. This information may be referred to by various names, such as Enabled link bitmap field / information / subfield / bit.

[0266] For example, the information related to the above-described Enabled link bitmap may have a bitmap of up to 16 bits in size only when the above-described SCA Enabled Presence value is set to the first value (or 1). Additionally or alternatively, the information related to the Enabled link bitmap may indicate a link for which the SCA Mode is enabled by setting the bit corresponding to each link to 1.

[0267] For example, as in the examples of FIGS. 21 to 23, three links between an AP MLD and a non-AP MLD are connected, and the Link ID of the first link may be 0, the Link ID of the second link may be 1, and the Link ID of the third link may be 2. In this example, to enable the SCA Mode of the links for Link ID 1 and Link ID 2, the bit corresponding to the corresponding link may be set to 1.

[0268] Disabled link bitmap (0 or 16 bits)

[0269] Below, information related to the Disabled link bitmap is described. This information may be referred to by various names, such as Disabled link bitmap field / information / subfield / bit.

[0270] For example, the information related to the above Disabled link bitmap may have a bitmap of up to 16 bits in size only when the above-described SCA Disabled Presence value is set to the first value (or 1). Additionally or alternatively, the information related to the Disabled link bitmap indicates a link for which the SCA Mode is to be disabled by setting the bit corresponding to each link to 1.

[0271] For example, as in the examples of FIGS. 21 to 23, three links between an AP MLD and a non-AP MLD are connected, and the Link ID of the first link may be 0, the Link ID of the second link may be 1, and the Link ID of the third link may be 2. In this example, to disable the SCA Mode of the links for Link ID 1 and Link ID 2, the bit corresponding to the corresponding link is set to 1.

[0272] Hereinafter, a second method will be described with reference to FIGS. 21 to 23. The operations of FIGS. 22 and 23 can be performed sequentially. That is, the operation of FIG. 22 can be represented by S2310 of FIG. 23. As illustrated in FIG. 21, AP 1 and AP 2 affiliated with the AP MLD are enabled, and AP3 is disabled. Also, as illustrated, STA 1 and STA 3 affiliated with the Non-AP MLD are enabled, and STA 2 is disabled. Accordingly, when the corresponding channel (PCH) is determined to be busy by the OBSS PPDU set on the PCH, only AP 1 and STA 1 can perform a switch to the SCH (e.g., the S20 channel or the NPCA primary channel) and then perform SCA / NPCA. Thereafter, a case may occur where the Non-AP MLD wants to enable Link 2 and disable Link 3. According to the second method described above, the Non-AP MLD can set the SCA Enabled Presence value to 1 and the SCA Disabled Presence value to 1. In addition, the Non-AP MLD can transmit an SCA Mode Notification frame by setting a bitmap of a link to be enabled and a bitmap of a link to be disabled. The AP MLD that receives the signal / frame can perform SCA with STA2 through Link 2. If the Non-AP MLD does not want to disable any link and only wants to enable Link 3, the SCA Disabled Presence value can be set to 0 and the Disabled Link Bitmap can have a length of 0 bit.The method illustrated in FIGS. 21 to 23 has the advantage of being able to individually set enable or disable for each link through one frame, compared to the method illustrated in FIGS. 19 and 20.

[0273] Additionally or alternatively, the examples of FIGS. 21 to 23 may be expressed differently as follows. The examples of FIGS. 21 to 23 are improvements over the examples of FIGS. 19 and 20, and the technical features of FIGS. 21 to 23 may operate together with the technical features of FIGS. 19 and 20. For example, the examples of the present specification relate to operations between a first MLD and a second MLD. For example, the first MLD may be an AP MLD of FIG. 21. The second MLD may be a non-AP MLD of FIG. 21. For example, the first MLD may perform multi-link operations related to multiple links (e.g., Link 1, Link 2, Link 3, etc. as shown in FIG. 21). For example, the first MLD may include affiliated STAs, and the affiliated STAs may be a plurality of STAs (e.g., AP 1, AP 2, AP 3 as shown in FIG. 21). For example, the second MLD may perform multilink operations related to a plurality of links (e.g., Link 1, Link 2, Link 3 as shown in FIG. 21). For example, the second MLD may include affiliated STAs, and the affiliated STAs may be a plurality of STAs (e.g., Non-AP STA 1, Non-AP STA 2, Non-AP STA AP 3 as shown in FIG. 21). A first STA (e.g., AP 1 illustrated in FIG. 23) according to the present specification may transmit a first management frame (e.g., Beacon illustrated in FIG. 22) to a second STA (e.g., STA 1 illustrated in FIG. 22) based on a first link (e.g., Link 1 illustrated in FIG. 21). For example, the first management frame (e.g.,, the Beacon illustrated in FIG. 22) may include first bitmap information (e.g., Enabled Link Bitmap illustrated in FIG. 22) related to the NPCA mode performed by the first MLD for the plurality of links. For example, the first bitmap information may be an enable bitmap (e.g., Enabled Link Bitmap illustrated in FIG. 22). For example, the enable bitmap may have a length of 16 bits. For example, one bit of the enable bitmap may be set to a first value (e.g., "1") based on the NPCA mode being enabled on the corresponding one link. Accordingly, in the example of FIG. 22, a value of "110" may be set corresponding to the SCA / NPCA mode of three links. For example, the first management frame (e.g., Beacon of FIG. 22) may further include enable presence information (e.g., SCA Enabled Presence of FIG. 22). For example, the enable presence information may have a length of 1 bit. For example, the value of the enable presence information may be set to a first value (e.g., "1") when at least one bit included in the enable bitmap (e.g., Enabled Link Bitmap included in Beacon of FIG. 22) is set to the first value. For example, the first management frame (e.g., Beacon of FIG. 22) may further include a disable bitmap (e.g., Disabled Link Bitmap included in Beacon of FIG. 22) having a length of 16 bits. One bit of the above disable bitmap may be set to a first value (e.g., "1") based on the NPCA mode being disabled on the corresponding link. Accordingly, in the example of FIG. 22, the value "001" may be set to correspond to the SCA / NPCA mode of three links.For example, the first management frame (e.g., Beacon of FIG. 22) may further include disable presence information (e.g., SCA Disabled Presence included in Beacon of FIG. 22). For example, the disable presence information may have a length of 1 bit. For example, the value of the disable presence information may be set to a first value (e.g., "1") when at least one bit included in the disable bitmap (e.g., Disabled Link Bitmap included in Beacon of FIG. 22) is set to the first value.

[0274] Additionally or alternatively, the examples of FIGS. 21 to 23 may be expressed differently as follows. For example, the first STA (e.g., AP1 illustrated in FIG. 22) may receive a second management frame (e.g., Association REQ frame illustrated in FIG. 22) from the second STA (e.g., STA 1 illustrated in FIG. 22) based on the first link (e.g., Link 1 illustrated in FIG. 21). For example, the second bitmap information (e.g., Enabled Link Bitmap included in Association REQ illustrated in FIG. 22) may have a length of 16 bits. For example, the second bitmap information may be an enable bitmap (e.g., Enabled Link Bitmap included in Association REQ illustrated in FIG. 22). For example, the enable bitmap may have a length of 16 bits. For example, one bit of the enable bitmap may be set to a first value (e.g., "1") based on the NPCA mode being enabled on the corresponding link. Accordingly, in the example of FIG. 22, the value "101" may be set corresponding to the SCA / NPCA modes of three links. For example, the first management frame (e.g., Association REQ of FIG. 22) may further include enable presence information (e.g., SCA Enabled Presence included in Association REQ of FIG. 22). For example, the enable presence information may have a length of 1 bit. For example, the value of the enable presence information may be set to a first value (e.g., "1") when at least one bit included in the enable bitmap (e.g., Enabled Link Bitmap included in Association REQ of FIG. 22) is set to the first value. For example, the second management frame (eg, the Association REQ of FIG. 22) may additionally include a disable bitmap (e.g., Disabled Link Bitmap included in the Association REQ of FIG. 22) having a length of 16 bits. One bit of the disable bitmap may be set to a first value (e.g., "1") based on the mode of NPCA being disabled on a corresponding link. Accordingly, in the example of FIG. 22, a value of "010" may be set corresponding to the SCA / NPCA mode of three links. For example, the second management frame (e.g., Association REQ of FIG. 22) may further include disable presence information (e.g., SCA Disabled Presence included in the Association REQ of FIG. 22). For example, the disable presence information may have a length of 1 bit. For example, the value of the disable presence information may be set to a first value (e.g., “1”) when at least one bit included in the disable bitmap (e.g., Association REQ Disabled Link Bitmap of FIG. 22) is set to the first value.

[0275] Additionally or alternatively, the examples of FIGS. 21 to 23 may be expressed differently as follows. For example, after the first management frame (e.g., Beacon illustrated in FIG. 22) and the second management frame (e.g., Association REQ frame illustrated in FIG. 22) are exchanged, NPCA / SCA by the first STA (e.g., AP 1 illustrated in FIG. 22) may be performed. For example, the first STA performs switching to an NPCA primary channel (e.g., S20 channel or SCH for back-off illustrated in FIG. 22) based on the Basic NAV being set for the Primary Channel of the first link. For example, the Basic NAV may be set by an OBSS PPDU received by the first STA (e.g., AP 1 illustrated in FIG. 22). After the first STA performs the NPCA primary channel switching, the first STA can obtain a TXOP for the NPCA primary channel based on performing a back-off on the NPCA primary channel. For example, based on the obtained TXOP, the first STA can transmit a frame (e.g., a Control frame to STA 1 as shown in FIG. 22) to a second STA (e.g., STA 1 as shown in FIG. 22) based on the NPCA primary channel (and at least one SCH / NPCA channel based on channel extension).

[0276] Additionally or alternatively, the examples of FIGS. 21 to 23 may be expressed differently as follows. For example, a second STA (e.g., AP 1 of FIGS. 22 and 23) may transmit a notification frame (e.g., SCA Mode Notification frame illustrated in FIG. 23) to a first STA (e.g., AP 1 of FIGS. 22 and 23). For example, the notification frame may include a disabled bitmap (Disabled Link Bitmap of FIG. 23) and / or an enabled bitmap (Enabled Link Bitmap of FIG. 23) that has been changed / updated by the second STA. For example, the notification frame may include enabled presence information (e.g., SCA Enabled Presence of FIG. 23) indicating that the disabled bitmap exists. For example, the notification frame may include disable presence information (e.g., SCA Disabled Presence of FIG. 23) indicating that the enable bitmap exists. When the notification frame is transmitted to the first STA, NPCA / SCA may be performed based on the notification frame exchanged between the first STA and the second STA (e.g., SCA Mode Notification frame illustrated in FIG. 23). For example, in the example of FIG. 23, after the SCA Mode Notification frame is exchanged, it may be confirmed by the AP MLD and the non-AP MLD that NPCA / SCA is enabled for Link 2 and NPCA / SCA is disabled for Link 3. Accordingly, in the example of FIG. 23, NPCA / SCA may be performed on Link 2, but NPCA / SCA may not be performed on Link 3.

[0277] A third method may be proposed involving information consisting of the following MLD-levels.

[0278] The third method described below relates to a technique for exchanging information regarding channel switching between STA 1 and STA 2 at the MLD level, for example, in the situation of FIG. 18. Furthermore, the information regarding channel switching related to the third method relates to NAV sharing, as illustrated in FIGS. 24 and 25. Below, NAV sharing will first be described, and then a technique for exchanging information regarding channel switching at the MLD level according to the third method will be described.

[0279] For example, in the example of FIG. 18, STA 1 (e.g., AP) and STA 2 (e.g., non-AP STA) cannot know exactly whether NAV (e.g., Basic NAV) is set on the PCH. In other words, although sharing NAV information with each other can be helpful for SCA / NPCA, it may be difficult to transmit information on a channel where NAV is set (e.g., P20 channel). Considering this, Multi-link operation can be utilized for NAV sharing. For example, in relation to NAV information, one or more pieces of information (at least one of information related to NAV information, Link ID, Channel Switch Indication, and / or Channel Switch Back Indication, described below) can be included. The information can be transmitted using a Data frame by including it in HE A-Control, etc., or based on a separate Management frame.

[0280] Among the various information related to NAV sharing, NAV Information is explained as follows.

[0281] NAV Information

[0282] The above-described NAV Information can indicate information about the remaining NAV duration from the start time (or end time) of the frame transmitting the corresponding NAV information. The remaining NAV information indicated through the above-described NAV Information can be indicated based on the 2 octets of the Duration / ID field included in the conventional MAC header. Additionally or alternatively, the field size (of the corresponding NAV information) can be reduced by using granularity (8us, 32us, 128us, etc.) like the TXOP field of the PHY header. For example, 1 to 2 bits can indicate the granularity, and the remaining 6 bits or more can be used to indicate the actual NAV duration information. Since the NAV duration indicated as above is information received from another link, the actual application can be determined based on the TSF of the link where the NAV is set.

[0283] The above-described NAV information can be modified as follows. For example, the NAV information can be used to indicate the end point of the NAV, rather than the NAV duration. For example, the end point of the NAV can be referred to as the NAV End Time, i.e., NAV_ET. Since the NAV_ET of one link must be reported from another link, each link's AP operates with its own TSF, so timing adjustments are necessary. For example, when transmitting NAV_ET from one link, the TSF of the corresponding link can be considered and transmitted. For example, if the TSF difference between two links is 30, it is desirable to indicate it with a drift of 30. However, if NAV_ET provides information of about 8 octets corresponding to the TSF, it may have excessive overhead. Therefore, like TWT, some bits of the TSF can be utilized to configure it as 2 octets.

[0284] Among the various information related to NAV sharing, the following explains Link ID.

[0285] The Link ID may be the ID of the link for which the above-described NAV duration (e.g., remaining NAV information indicated by the NAV information or information regarding NAV_ET) is set. The Link ID may have a length of 4 bits, or a length of 1 / 2 / 3 bits, or a length of 5 or more bits.

[0286] Figures 24 and 25 are drawings explaining operations related to NAV sharing.

[0287] For example, as illustrated in FIG. 24, the AP MLD may include at least two APs (e.g., AP 1, AP 2), and the non-AP MLD may include at least two non-AP STAs (non-AP STA 1, non-AP STA 2).

[0288] Figures 24 and 25 illustrate examples of Basic NAV Sharing using AP MLD. As illustrated, Basic NAV can be set by AP 1 in PCH (PCH 1 or P20 channel illustrated). In this case, as illustrated in Figure 25, AP 2 can individually announce NAV information for AP 1 (AP 1's NAV information illustrated) to an STA in a frame or broadcast it so that multiple STAs can recognize it. At this time, in the non-AP MLD that recognizes this, NAV sharing is performed within the MLD as illustrated in Figure 25. Specifically, as illustrated in Figure 25, when NAV information for AP 1 (AP 1's NAV information illustrated) is received by non-AP STA 2, the received information can be shared within the non-AP MLD. Through this, non-AP STA 1 can obtain the received information (AP 1's NAV information). As a result, non-AP STA 1 can switch to the SCH even if the current PCH (e.g., PCH 1 illustrated in FIG. 24) is IDLE because it can expect that the illustrated AP 1 will perform SCA.

[0289] Additionally or alternatively, the present specification may propose information regarding Channel Switch Indication and information regarding Channel Switch Back Indication.

[0290] Channel Switch Indication

[0291] The above information may be information / field / subfield / bit indicating that a switch has been made to the SCH (or S20 channel, or NPCA primary channel). For example, the information related to the Channel Switch Indication may have a length of 1 bit.

[0292] Channel Switch Back Indication:

[0293] The above information may be information / field / subfield / bit indicating that a switch has been made to the PCH (or P20 channel). For example, the information related to the Channel Switch Back Indication may have a length of 1 bit.

[0294] For example, a Basic NAV may be set in the PCH (e.g., P20 channel or PCH 1) of a non-AP STA 1 as shown in FIG. 25. In this case, a non-AP STA 2 may include information (e.g., setting the Channel Switch Indication to the first value (e.g., 1)) regarding whether the Basic NAV has been set in the PCH (e.g., P20 channel or PCH 1) by the non-AP STA 1 and has switched to the SCH (e.g., S20 channel or NPCA primary channel) in a frame to be transmitted to AP 2. When the AP 2 of FIG. 25 receives the frame, the related information is shared internally in the AP MLD, and as a result, the AP 1 included in the AP MLD can recognize / confirm the channel switching of the non-AP STA 1. For example, the AP 1 may determine that the channel on which the non-AP STA 1 is performing back-off by switching to the SCH is not aligned with the channel of the AP 1. Accordingly, AP 1 can transmit frames to STAs other than non-AP STA 1. This prevents the AP from engaging in unnecessary frame exchanges (i.e., unsuccessful frame exchanges) with STA 1, thereby preventing the CW value of the AP from increasing unnecessarily.

[0295] Additionally or alternatively, the Channel Switch Back Indication value may be set to a first value (e.g., 1) to notify AP 1 (or AP MLD) that non-AP STA 1 has switched back to the PCH. Additionally or alternatively, the Channel Switch Indication information may be transmitted together with information related to the NAV information described above. Through this, the AP receiving the information can obtain information about when non-AP STA 1 switches back to the PCH.

[0296] Various examples including the first method, the second method and the third method described above can be represented by a procedure flowchart.

[0297] Fig. 26 is a flowchart illustrating an example of the above-described specification. Fig. 26 may be related to a transmission process of an STA. The operation of Fig. 26 may be an operation performed by a first STA (e.g., an AP). According to step S2610, a first STA (e.g., an AP) having SCA Capability may set its SCA Mode to a first value or a second value and perform an announcement. According to step S2620, the first STA may receive a response to the SCA mode transmitted by itself from at least one second STA (e.g., a non-AP STA). According to step S2630, if the SCA mode of all second STAs (e.g., all non-AP STAs) is set to the second value (e.g., 0), even if the PCH is determined to be busy due to an OBSS PPDU, the first STA may not perform a switch to the SCH. According to step S2640, if the SCA mode of at least one second STA is set to the first value (e.g., 1), and if the PCH is determined to be busy due to an OBSS PPDU, the first STA may perform switching to the SCH and perform SCA with the at least one second STA.

[0298] Fig. 27 is a flowchart illustrating an example of the above-described specification. Fig. 27 may be related to a receiving process of an STA. The operation of Fig. 27 may be an operation performed by a second STA (e.g., a non-AP STA). According to step S2710, the second STA may receive a frame related to the SCA Mode of the first STA from a first STA (e.g., an AP) having SCA Capability. According to step S2720, if the SCA Mode of the first STA (e.g., an AP) is the second value (e.g., 0), the second STA (e.g., a non-AP STA) may notify its SCA mode to the first STA or set its SCA mode to the second value (e.g., ). According to step S2730, the second STA may maintain the SCA mode as 0 until the SCA Mode of the first STA (e.g., an AP) is updated to 1. According to step S2740, if the SCA Mode of the first STA (eg, AP) is updated to 1, the second STA (eg, non-AP STA) can return to the originally set SCA mode (e.g., the SCA Mode corresponding to the first value). According to step S2740, the second STA (non-AP STA) can notify its SCA Mode to the AP if the SCA mode of the first STA (AP) is the first value (eg, 1). According to step S2750, only when the SCA mode of the first STA (AP) is the first value (eg, 1), the second STA (non-AP STA) can determine whether the PCH is busy due to an OBSS PPDU, and if the PCH is busy, perform switching to the SCH to perform SCA.

[0299] Various examples, including the first, second, and third methods according to the present specification, can be modified in various ways. Various examples of the present specification can operate according to the following technical features.

[0300] An STA (e.g., an AP or non-AP STA) performing SCA / NPCA of the present specification may transmit frames / PPDUs on an SCH even during the time when a NAV (e.g., Basic NAV) is set in the PCH. For example, the STA (e.g., an AP or non-AP STA) may obtain an IDLE state determined by a backoff performed on one or more SCHs (e.g., an S20 channel or an NPCA primary channel) (and a CCA result of one or more SCHs on which backoff is not performed). This allows the STA to transmit frames / PPDUs (excluding / puncturing the PCH) through at least one SCH.

[0301] Additionally or alternatively, a TXOP initiated by a frame / PPDU transmission on the SCH (e.g., S20 channel or NPCA primary channel) may be configured to end before the NAV on the PCH ends. The TXOP length may be configured / indicated via the duration / ID field of the corresponding frame. For example, the value of the duration / ID field may be set to a value representing the time required for the exchange of a frame / PPDU following the corresponding frame / PPDU (including the interframe gap (IFS)).

[0302] Additionally or alternatively, the EDCA Parameter Set for each SCH on which back-off is performed may be set to the EDCA Parameter Set in the PCH, the MU EDCA Parameter Set, or a new EDCA Parameter Set. This EDCA Parameter Set may be applied equally to all SCHs or individually (or differently) from each other.

[0303] In this specification, an STA (e.g., an AP or non-AP STA) receiving a frame transmitted via SCA / NPCA can perform frame detection on an SCH (e.g., an S20 channel or an NPCA primary channel) even during the time when a NAV (e.g., a Basic NAV) is set in the PCH. For example, an STA (e.g., an AP or non-AP STA) may perform a backoff on the SCH because it has a frame to transmit, or may attempt to receive a frame addressed to itself on the SCA even when it has no frame to transmit. In addition, the STA may perform NAV setting / resetting based on the value of the duration / ID field of a frame detected on the SCH.

[0304] Additionally or alternatively, the EDCA Parameter Set for each SCH on which back-off is performed may be set to the EDCA Parameter Set in the PCH, the MU EDCA Parameter Set, or a new EDCA Parameter Set. This EDCA Parameter Set may be applied equally or individually (or differently) to all SCHs.

[0305] Additionally or alternatively, STAs and APs with SCA capabilities can determine whether the STA or AP performs SCA by including an indication of whether or not to perform SCA in a Management frame (e.g., Beacon, Probe Request / Response frame, SCA Mode Request / Response frame, etc.) when Basic NAV is set in the PCH.

[0306] Additionally or alternatively, if SCA Mode is disabled (SCA Allowed is set to 0), an indication of how long SCA Mode will remain disabled can be provided via the SCA Disabled count field.

[0307] Additionally or alternatively, the AP MLD or Non-AP MLD can indicate whether to enable / disable SCA Mode for each link via the SCA Mode Link Bitmap.

[0308] Additionally or alternatively, one frame can individually indicate whether multiple links are disabled / enabled via the Enabled link bitmap, Disabled link bitmap, SCA Enabled Presence, and SCA Disabled Presence.

[0309] Figure 28 is a flowchart illustrating an example of the present specification. For convenience of explanation, the example of Figure 28 is described as being performed by the first STA. However, the example of the present specification may also be performed by the MLD. That is, each step of Figure 28 may be expressed as being performed by the first STA, or may be expressed as being performed by the first MLD affiliated with the first STA.

[0310] Step S2810 relates to a step of transmitting a first management frame to a second STA by a first STA (Station), as illustrated. For example, the first management frame may be transmitted via a first link. For example, the first STA may be an AP or a non-AP STA. For example, the first STA may be any one of a plurality of APs affiliated with an AP MLD. For example, the first STA may be any one of a plurality of non-AP STAs affiliated with a non-AP STA MLD. For example, the first STA may be AP 1 illustrated in any one of FIGS. 19 to 25 , or STA 1 (or non-AP STA 1) illustrated in any one of FIGS. 19 to 25 . For example, the second STA may be STA 1 (or non-AP STA 1) illustrated in any one of FIGS. 19 to 25, or AP 1 illustrated in any one of FIGS. 19 to 25.

[0311] For example, the first management frame may include first bitmap information related to the Non-Primary Channel Access (NPCA) mode performed by the first MLD for the plurality of links. For example, the first management frame may be a Beacon as illustrated in FIG. 20 or FIG. 22. For example, the first bitmap information related to the Non-Primary Channel Access (NPCA) mode may be an SCA Mode Link bitmap as illustrated in FIG. 20.

[0312] Additionally or alternatively, the first management frame may further include NPCA capability information regarding whether the first STA has a capability related to NPCA. For example, the NPCA capability information may be information related to the aforementioned Secondary Channel Access Capability. For example, the NPCA capability information may have a length of 1 bit.

[0313] Additionally or alternatively, the first management frame may further include first NPCA mode information related to the NPCA mode of the first STA. For example, the first NPCA mode information may be SCA Mode information included in the Beacon illustrated in FIG. 20. For example, the first NPCA mode information may be set to a first value based on whether the NPCA mode of the first STA is enabled. For example, the first NPCA mode information may be set to a second value based on whether the NPCA mode of the first STA is disabled.

[0314] Additionally or alternatively, the first management frame may further include an enable bitmap. For example, the enable bitmap may be an Enabled Link Bitmap included in the Beacon of FIG. 22. Additionally or alternatively, the first management frame may further include enable presence information. For example, the enable presence information may be 1-bit information indicating whether the enable bitmap exists. For example, the enable presence information may be SCA Enabled presence information included in the Beacon of FIG. 22.

[0315] Additionally or alternatively, the first management frame may further include a disable bitmap. For example, the disable bitmap may be a Disabled Link Bitmap included in the Beacon of FIG. 22. Additionally or alternatively, the first management frame may further include disable presence information. For example, the disable presence information may be 1-bit information indicating whether the disable bitmap exists. For example, the disable presence information may be SCA Disabled presence information included in the Beacon of FIG. 22.

[0316] Additionally or alternatively, the first management frame may further include first information regarding whether another STA associated with the first MLD has switched to the NPCA primary channel. For example, the first information may be the Channel Switch Indication information described above.

[0317] Additionally or alternatively, the second information may further include whether another STA associated with the first MLD has switched from the NPCA primary channel to the primary channel. For example, the second information may be the Channel Switch Back Indication information described above.

[0318] Step S2820 relates to a step of receiving a second management frame from the second STA by the first STA, as illustrated. For example, the second management frame may be received via the first link.

[0319] Additionally or alternatively, the second management frame may further include NPCA capability information regarding whether the second STA has a capability related to NPCA. For example, the NPCA capability information may be information related to the aforementioned Secondary Channel Access Capability. For example, the NPCA capability information may have a length of 1 bit.

[0320] Additionally or alternatively, the second management frame may further include second NPCA mode information related to the NPCA mode of the second STA. For example, the second NPCA mode information may be SCA Mode information included in the Association REQ illustrated in FIG. 20. For example, the second NPCA mode information may be set to a first value based on the NPCA mode of the second STA being enabled. For example, the second NPCA mode information may be set to a second value based on the NPCA mode of the second STA being disabled.

[0321] Additionally or alternatively, the second management frame may further include an enable bitmap. For example, the enable bitmap may be an Enabled Link Bitmap included in the Association REQ of FIG. 22. Additionally or alternatively, the second management frame may further include enable presence information. For example, the enable presence information may be 1-bit information indicating whether the enable bitmap exists. For example, the enable presence information may be SCA Enabled presence information included in the Association REQ of FIG. 22.

[0322] Additionally or alternatively, the second management frame may further include a disable bitmap. For example, the disable bitmap may be a Disabled Link Bitmap included in the Association REQ of FIG. 22. Additionally or alternatively, the second management frame may further include disable presence information. For example, the disable presence information may be 1-bit information indicating whether the disable bitmap exists. For example, the disable presence information may be SCA Disabled presence information included in the Association REQ of FIG. 22.

[0323] Based on the illustrated step S2830, NPCA / SCA can be performed based on the first and second management frames. For example, the first STA performs switching to an NPCA primary channel (e.g., S20 channel or SCH for back-off of FIG. 22) based on the Basic NAV being set for the Primary Channel of the first link. For example, the Basic NAV can be set by an OBSS PPDU received by the first STA (e.g., AP 1 of FIG. 22). After the first STA performs the NPCA primary channel switching, the first STA can obtain a TXOP for the NPCA primary channel based on performing back-off on the NPCA primary channel. For example, based on the acquired TXOP, the first STA can transmit a frame (e.g., a Control frame to STA 1 as shown in FIG. 22) to the second STA (e.g., STA 1 as shown in FIG. 22) based on the NPCA primary channel (and at least one SCH / NPCA channel based on channel extension). Step S2830 is not a mandatory step and the performance of the operation may be omitted. Alternatively, step S2830 may be performed after step S2840 described below is performed.

[0324] Based on the illustrated step S2840, the second STA (e.g., AP 1 of FIGS. 22 and 23) may transmit a notification frame (e.g., SCA Mode Notification frame of FIG. 23) to the first STA (e.g., AP 1 of FIGS. 22 and 23). For example, the notification frame may include a disabled bitmap (e.g., Disabled Link Bitmap of FIG. 23) and / or an enabled bitmap (e.g., Enabled Link Bitmap of FIG. 23) that has been changed / updated by the second STA. For example, the notification frame may include enabled presence information (e.g., SCA Enabled Presence of FIG. 23) indicating that the disabled bitmap exists. For example, the notification frame may include disabled presence information (e.g., SCA Disabled Presence of FIG. 23) indicating that the enabled bitmap exists. When the above notification frame is transmitted to the first STA, NPCA / SCA can be performed based on the notification frame exchanged between the first STA and the second STA (e.g., the SCA Mode Notification frame illustrated in FIG. 23).

[0325] Additionally or alternatively, step S2840 may be performed by the first STA rather than the second STA. Specifically, the notification frame may include a disable bitmap and / or an enable bitmap that has been changed / updated by the first STA. For example, the notification frame may be generated by the first STA and transmitted to the second STA. Step S2840 is not a mandatory step and may be omitted from performing the operation.

[0326] Figure 29 is a flowchart illustrating an example of the present specification. For convenience of explanation, the example in Figure 29 is described as being performed by a second STA. However, the example in this specification may also be performed by an MLD. That is, each step in Figure 29 may be expressed as being performed by the second STA, or may be expressed as being performed by a second MLD affiliated with the second STA.

[0327] Step S2910, as illustrated, relates to a step in which a second STA receives a first management frame from a first STA. For example, the technical characteristics applied to the first management frame of step S2910 may be identical to those of step S2810. Accordingly, any redundant description will be omitted.

[0328] Step S2920 relates to a step of transmitting a second management frame to the first STA (Station), by the second STA, as illustrated. For example, the technical characteristics applied to the second management frame of step S2920 may be identical to those of step S2820. Accordingly, any redundant description will be omitted.

[0329] Based on the illustrated step S2930, NPCA / SCA can be performed based on the first and second management frames. For example, the technical characteristics of step S2930 may be identical to those of step S2830. Accordingly, any redundant description will be omitted.

[0330] Based on the illustrated step S2940, the first STA or the second STA may transmit the aforementioned notification frame (e.g., the SCA Mode Notification frame illustrated in FIG. 23). The notification frame of the above-described step S2940 may be identical to the above-described step S2930. Accordingly, any redundant description will be omitted.

[0331] The technical features of the present disclosure may be implemented by various devices. The devices of the present disclosure may be the devices described in FIG. 1 / FIG. 14. The devices of the present disclosure may include at least one processor; and at least one computer memory operably connectable to the at least one processor, the computer memory storing instructions for performing operations based on execution by the at least one processor.

[0332] For example, the processor may be a processor described in FIG. 1 and / or FIG. 14. That is, as described above, the processor of the present specification may include at least one of a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), and a modem (modulator and demodulator). The processor may include not only computers having various architectures such as single / multiprocessor architecture, sequential (Von Neumann) / parallel architecture, but also specialized circuits such as FPGAs, ASICs, signal processing devices, and other devices. For example, the processor of the present specification may be a SNAPDRAGON® series processor manufactured by Qualcomm®, an EXYNOS® series processor manufactured by Samsung®, an A series processor manufactured by Apple®, a HELIO® series processor manufactured by MediaTek®, an ATOM® series processor manufactured by INTEL®, or a processor that enhances the same.

[0333] For example, the instructions may refer to computer program instructions executed by the at least one processor. The (computer program) instructions provide logic and / or routines that enable the technical features of the present specification to be performed by the processor. The at least one processor can load and execute a computer program by reading the at least one memory.

[0334] The computer program(s) defined by the above instructions may be delivered to the device (e.g., STA) of the present specification via an appropriate delivery mechanism. The delivery mechanism may be, for example, a computer-readable storage medium, a computer program product, a memory device, a recording medium such as a CD-ROM or DVD, or a product tangibly embodying the computer program. The delivery mechanism may be a signal configured to reliably transmit the computer program via a wireless or electrical connection.

[0335] The above (computer program) instructions may include software or firmware for a programmable processor (e.g., programmable content of a hardware device whether instructions for a processor, or configuration settings for a fixed-function device, gate array or programmable logic device, etc.).

[0336] For example, the memory may be the memory described in FIG. 1 and / or FIG. 14. That is, as described above, the memory of the present specification may store control information related to the operation of the STA of the present specification or information about signals transmitted and received by the STA (e.g., PPDU including management / control / data frames).

[0337] The technical features of this specification may be implemented in at least one computer-readable recording medium (CRM). The CRM includes instructions that are executed by at least one processor as described above. The instructions stored in the CRM may be computer program instructions as described above.

[0338] The device of the present disclosure may further include a transceiver. The transceiver may be operably connectable to the memory / processor, etc. The transceiver may be the transceiver illustrated in FIG. 1 and / or FIG. 14.

[0339] The technical features of this specification described above are applicable to various applications and business models. For example, the technical features described above can be applied to wireless communication in devices that support artificial intelligence (AI).

[0340] Artificial intelligence (AI) is the study of artificial intelligence or the methodologies for creating it, while machine learning (ML) defines various problems in the field of AI and studies the methodologies for solving them. Machine learning is also defined as an algorithm that improves performance on a task through consistent experience.

[0341] An artificial neural network (ANN) is a model used in machine learning. It can refer to a model with problem-solving capabilities, consisting of artificial neurons (nodes) formed by the connection of synapses to form a network. An ANN can be defined by the connection patterns between neurons in different layers, the learning process that updates model parameters, and the activation function that generates output values.

[0342] An artificial neural network may include an input layer, an output layer, and optionally one or more hidden layers. Each layer contains one or more neurons, and the artificial neural network may include synapses connecting neurons. In an artificial neural network, each neuron can output a function value of an activation function based on input signals, weights, and biases received through the synapses.

[0343] Model parameters are parameters determined through learning, including synaptic connection weights and neuron biases. Hyperparameters are parameters that must be set before learning in machine learning algorithms, including the learning rate, number of iterations, mini-batch size, and initialization function.

[0344] The goal of artificial neural network training can be seen as determining model parameters that minimize a loss function. The loss function can be used as an indicator for determining optimal model parameters during the artificial neural network training process.

[0345] Machine learning can be classified into supervised learning, unsupervised learning, and reinforcement learning depending on the learning method.

[0346] Supervised learning refers to a method for training an artificial neural network when given labels for the training data. The labels can refer to the correct answer (or output value) that the artificial neural network must infer when the training data is input to the artificial neural network. Unsupervised learning can refer to a method for training an artificial neural network when the training data is not given labels. Reinforcement learning can refer to a learning method in which an agent defined within a given environment is trained to select actions or action sequences that maximize the cumulative reward in each state.

[0347] Machine learning implemented with a deep neural network (DNN) containing multiple hidden layers among artificial neural networks is also called deep learning, and deep learning is a subset of machine learning. Hereinafter, the term "machine learning" is used to encompass deep learning.

[0348] Additionally, the above-described technical features can be applied to wireless communication of robots.

[0349] A robot can be defined as a machine that automatically performs or operates a given task based on its own capabilities. Specifically, a robot capable of perceiving its environment, making independent judgments, and performing actions can be called an intelligent robot.

[0350] Robots can be categorized into industrial, medical, household, and military applications based on their intended use or field. Robots are equipped with actuators or motors, enabling them to perform various physical actions, such as moving robot joints. Furthermore, mobile robots incorporate wheels, brakes, and propellers into their actuators, enabling them to move on the ground or fly in the air.

[0351] Additionally, the above-described technical features can be applied to devices that support extended reality.

[0352] Extended reality is a general term for virtual reality (VR), augmented reality (AR), and mixed reality (MR). VR technology presents real-world objects and backgrounds as CG images only, AR technology presents virtual CG images over images of real objects, and MR technology is a computer graphics technology that blends and combines virtual objects with the real world.

[0353] MR technology is similar to AR in that it presents both real and virtual objects simultaneously. However, while AR uses virtual objects to complement real objects, MR uses virtual and real objects on an equal footing.

[0354] XR technology can be applied to HMD (Head-Mount Display), HUD (Head-Up Display), mobile phones, tablet PCs, laptops, desktops, TVs, digital signage, etc., and devices to which XR technology is applied can be called XR devices.

Claims

1. The first STA (Station) transmits a first management frame to the second STA based on the first link. The first STA is affiliated to a first MLD (Multi-Link Device) that performs a multi-link operation related to a plurality of links, and the second STA is affiliated to a second MLD that performs a multi-link operation related to the plurality of links. The first management frame comprises first bitmap information related to a Non-Primary Channel Access (NPCA) mode performed by the first MLD for the plurality of links; and By the first STA, based on the first link, a second management frame is received from the second STA, The second management frame comprises second bitmap information related to the NPCA mode performed by the second MLD for the plurality of links. Including method.

2. In paragraph 1, The above first bitmap information is configured based on a first bitmap having a length of 16 bits, One bit of the first bitmap indicates whether the first MLD performs NPCA on one link corresponding to the one bit. method.

3. In paragraph 1, The first management frame further includes NPCA capability information regarding whether the first STA has a capability related to NPCA, The above NPCA capability information has a length of 1 bit. method.

4. In paragraph 1, The first management frame further includes first NPCA mode information related to the NPCA mode of the first STA, The above first NPCA mode information is set to a first value based on the NPCA mode of the first STA being enabled. method.

5. In paragraph 1, The above first management frame further includes enable presence information, The above enable presence information has a length of 1 bit, The above first bit app information is an enable bitmap, The above enable bitmap has a length of 16 bits, One bit of the above enable bitmap is set to a first value based on the mode of NPCA being enabled on one link corresponding to the one bit, The value of the above enable presence information is determined based on whether at least one bit included in the enable bitmap is set to the first value. method.

6. In paragraph 5, The above first management frame further includes disable presence information, The above disable presence information has a length of 1 bit, The above first management frame additionally includes a disable bitmap having a length of 16 bits, One bit of the above disable bitmap is set to a first value based on the mode of NPCA being disabled on one link corresponding to one bit included in the above disable bitmap, The value of the above disable presence information is determined based on whether at least one bit included in the disable bitmap is set to the first value. method.

7. In paragraph 1, The above first management frame further includes first information related to whether another STA associated with the first MLD has switched to the NPCA primary channel, The above first information has a length of 1 bit. method.

8. In paragraph 1, The above first management frame further includes second information related to whether another STA associated with the first MLD has switched from the NPCA primary channel to the primary channel, The above second information has a length of 1 bit. method.

9. In paragraph 1, The above first MLD is an AP (Access Point) MLD, and the above first STA is a first AP. The above second MLD is a non-AP STA MLD, and the above second STA is a first non-AP STA. method.

10. In paragraph 1, The above first management frame is at least one of a beacon frame, an association response frame, and a probe response frame. method.

11. At least one processor included in the first STA (Station); and At least one computer memory operably connectable to said at least one processor, said computer memory storing instructions for performing operations based on execution by said at least one processor, The instructions of at least one computer memory, By the first STA (Station), a first management frame is transmitted to the second STA based on the first link, The first STA is affiliated to a first MLD (Multi-Link Device) that performs a multi-link operation related to a plurality of links, and the second STA is affiliated to a second MLD that performs a multi-link operation related to the plurality of links. The first management frame comprises first bitmap information related to a Non-Primary Channel Access (NPCA) mode performed by the first MLD for the plurality of links; and By the first STA, based on the first link, a second management frame is received from the second STA, The second management frame comprises second bitmap information related to the NPCA mode performed by the second MLD for the plurality of links. Performing the action of 1st STA.

12. In the 11th paragraph, the command of at least one computer memory performs an operation related to any one of the 2nd to 10th paragraphs. 1st STA.

13. The second STA receives the first management frame from the first STA (Station) based on the first link. The first STA is affiliated to a first MLD (Multi-Link Device) that performs a multi-link operation related to a plurality of links, and the second STA is affiliated to a second MLD that performs a multi-link operation related to the plurality of links. The step of the first management frame including first bitmap information related to the Non-Primary Channel Access (NPCA) mode performed by the first MLD for the plurality of links; and By the second STA, based on the first link, a second management frame is transmitted to the first STA, The second management frame comprises second bitmap information related to the NPCA mode performed by the second MLD for the plurality of links. Including method.

14. In the 13th paragraph, the second STA performs an operation related to any one of the 2nd to 10th paragraphs. method.

15. At least one processor included in the second STA (Station); and At least one computer memory operably connectable to said at least one processor, said computer memory storing instructions for performing operations based on being executed by said at least one processor, The instructions of at least one computer memory, By the second STA, a first management frame is received from the first STA (Station) based on the first link, The first STA is affiliated to a first MLD (Multi-Link Device) that performs a multi-link operation related to a plurality of links, and the second STA is affiliated to a second MLD that performs a multi-link operation related to the plurality of links. The step of the first management frame including first bitmap information related to the Non-Primary Channel Access (NPCA) mode performed by the first MLD for the plurality of links; and By the second STA, based on the first link, a second management frame is transmitted to the first STA, The second management frame comprises second bitmap information related to the NPCA mode performed by the second MLD for the plurality of links. Performing the action of 2nd STA.

16. In the 15th paragraph, the second STA performs an operation related to any one of the 2nd to 10th paragraphs. method.

17. In a wireless local area network (WLAN) system, at least one computer readable medium including instructions based on being executed by at least one processor, By the first STA (Station), based on the first link, a first management frame is transmitted to the second STA, The first STA is affiliated to a first MLD (Multi-Link Device) that performs a multi-link operation related to a plurality of links, and the second STA is affiliated to a second MLD that performs a multi-link operation related to the plurality of links. The step of the first management frame including first bitmap information related to the Non-Primary Channel Access (NPCA) mode performed by the first MLD for the plurality of links; and By the first STA, based on the first link, a second management frame is received from the second STA, The second management frame comprises second bitmap information related to the NPCA mode performed by the second MLD for the plurality of links. Performing an operation that includes Recording medium.

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