Method and device for transmitting PPDU by accessing non-primary channel in wireless LAN system

Abstract

Proposed are a method and device for transmitting a PPDU by accessing a non-primary channel in a wireless LAN system. Specifically, a reception STA performs backoff on a first non-primary channel. The reception STA performs channel access to a second non-primary channel when the value of the backoff on the first non-primary channel is zero. The reception STA transmits the PPDU to a transmission STA through an idle channel among the first and second non-primary channels. The first non-primary channel is a secondary 20 MHz channel on which the backoff can be performed while an NAV is set in a primary 20 MHz channel. The second non-primary channel is a secondary channel other than the first non-primary channel in a BSS operating channel.

Description

Method and device for transmitting PPDU by accessing non-primary channel in wireless LAN system The present specification relates to a technique for transmitting a PPDU by accessing a non-primary channel in a wireless LAN system, and more specifically, to a method and device for configuring limited rules for determining the location of a non-primary channel within a BSS operating channel of an AP. Next-generation Wi-Fi (e.g., IEEE 802.11be and / or later) aims to support ultra-high reliability when transmitting signals to STAs. To achieve this, various technologies are being considered to support high throughput, low latency, and extended range. For example, procedures for accessing non-primary channels can be performed. The present specification proposes a method and device for transmitting a PPDU by accessing a non-primary channel in a wireless LAN system. An example of this specification proposes a method for transmitting a PPDU by accessing a non-primary channel. The present embodiment can be performed in a network environment that supports a next-generation wireless LAN system (UHR (Ultra High Reliability) wireless LAN system or next wi-fi). The next-generation wireless LAN system is a wireless LAN system that improves the 802.11be system and can satisfy backward compatibility with the 802.11be system. The present embodiment is performed in a receiving STA, and the receiving STA may correspond to at least one STA (station). The transmitting STA of the present embodiment may correspond to an AP (access point). This embodiment proposes a method for transmitting and receiving PPDUs by performing backoff on a non-primary channel and performing channel access on another non-primary channel based on this backoff. In particular, this embodiment proposes limited rules for determining the location of a non-primary channel within an AP's BSS operating channel. The receiving STA (station) performs a backoff on the first non-primary channel. The receiving STA performs channel access for the second non-primary channel when the backoff value for the first non-primary channel is 0. The receiving STA transmits a PPDU to the transmitting STA through an IDLE channel among the first and second non-primary channels. The above first non-primary channel is a secondary 20MHz channel that can perform the above backoff while the NAV (Network Allocation Vector) is set in the primary 20MHz channel. The above second non-primary channel is a secondary channel excluding the first non-primary channel in the BSS (Basic Service Set) operating channel. The above first non-primary channel is located in a secondary channel having half the size of the BSS operating channel. That is, the present embodiment proposes a method for performing channel access for a non-primary channel (or secondary channel) in a situation where a NAV (Basic NAV here) is set for the primary 20 MHz channel. This embodiment maximizes channel utilization in terms of PPDU bandwidth and puncturing patterns by proposing limited rules for determining the location of a non-primary channel within an AP's BSS operating channel. Furthermore, by determining a non-primary channel based on the overlap between OBSS traffic and the non-primary channel, this embodiment can provide advantages in terms of the probability of performing channel access to the non-primary channel, and can also enhance the efficiency of bandwidth utilization. Figure 1 illustrates an example of a transmitting device and / or a receiving device of the present specification. Figure 2 is a conceptual diagram showing the structure of a wireless local area network (WLAN). Figure 3 is a diagram illustrating a general link setup process. Figure 4 illustrates one embodiment of a multi-link (ML). FIG. 5 illustrates a PPDU (physical protocol data unit or physical layer (PHY) protocol data unit) transmitted / received by an STA of this specification. Figure 6 is a diagram showing the layout of resource units (RUs) used for 20MHz PPDU. Figure 7 is a diagram showing the layout of resource units (RUs) used for 40MHz PPDU. Figure 8 is a diagram showing the layout of resource units (RUs) used for 80MHz PPDU. Figure 9 shows the operation according to UL-MU. Figure 10 shows an example of channels used / supported / defined within the 2.4 GHz band. Figure 11 illustrates an example of channels used / supported / defined within the 5 GHz band. Figure 12 illustrates an example of channels used / supported / defined within the 6 GHz band. Figure 13 shows an example of a header of a MAC frame. FIG. 14 illustrates a modified example of a transmitting device and / or a receiving device of the present specification. Figure 15 illustrates an example of channel access in an 802.11 wireless LAN system. Figure 16 illustrates an example of the basic procedure of SCA. Figure 17 shows the basic Secondary Channel Access operation process of STA. Figure 18 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 320 MHz and SCA P20 is the fifth 20 MHz channel. Figure 19 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 160 MHz and SCA P20 is the second 20 MHz channel. Figure 20 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 160 MHz and SCA P20 is the third 20 MHz channel. Figure 21 illustrates an example of a channel configuration for a Secondary Channel Access Channel when the BSS Operating Bandwidth is 160 MHz and SCA P20 is the fifth 20 MHz channel. Figure 22 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 320 MHz and SCA P20 is the second 20 MHz channel. Figure 23 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 320 MHz and SCA P20 is the third 20 MHz channel. Figure 24 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 320 MHz and SCA P20 is the ninth 20 MHz channel. Figure 25 illustrates an example of transmitting a Wide Bandwidth Frame in Secondary Channel Access when the BSS Operating Bandwidth is 160 MHz and SCA P20 is the second 20 MHz channel. Figure 26 illustrates an example of transmitting a Wide Bandwidth Frame in Secondary Channel Access when the BSS Operating Bandwidth is 160 MHz and SCA P20 is the third 20 MHz channel. Figure 27 illustrates an example of transmitting a Wide Bandwidth Frame in Secondary Channel Access when the BSS Operating Bandwidth is 160 MHz and SCA P20 is the fifth 20 MHz channel. Figure 28 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 80 MHz and SCA P20 is the second 20 MHz channel. Figure 29 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 80 MHz and SCA P20 is the third 20 MHz channel. Figure 30 is a flowchart illustrating the operation of a transmitting device according to the present embodiment. Figure 31 is a flowchart illustrating the operation of a receiving device according to the present embodiment. FIG. 32 is a flowchart illustrating a procedure in which a transmitting STA accesses a non-primary channel and receives a PPDU according to the present embodiment. FIG. 33 is a flowchart illustrating a procedure in which a receiving STA accesses a non-primary channel and transmits a PPDU according to the present embodiment. In this specification, “A or B” can mean “only A,” “only B,” or “both A and B.” In other words, “A or B” in this specification can be interpreted as “A and / or B.” For example, “A, B or C” in this specification can mean “only A,” “only B,” “only C,” or “any combination of A, B, and C.” As used herein, a slash ( / ) or a comma can mean "and / or." For example, "A / B" can mean "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." In this specification, “at least one of A and B” can 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” can be interpreted identically to “at least one of A and B.” In addition, parentheses used in this specification may mean “for example.” Specifically, when “control information (UHR-Signal field)” is indicated, the “UHR-Signal field” may be suggested 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 suggested as an example of “control information.” In addition, even when indicated as “control information (UHR-Signal field),” the “UHR-Signal field” may be suggested as an example of “control information.” 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.” 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.” Technical features individually described in a single drawing in this specification may be implemented individually or simultaneously. 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 following examples of this 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 following examples of this specification can be applied to mobile communication systems based on the Long Term Evolution (LTE) and its evolution based on the 3rd Generation Partnership Project (3GPP) standard. In order to explain the technical features of this specification, the technical features to which this specification can be applied are described below. Figure 1 illustrates an example of a transmitting device and / or a receiving device of the present specification. 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. 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. 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). 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. Based on the sub-drawing (a) of Fig. 1, STA (110, 120) is described as follows. 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. 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.). 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). 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.). 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). 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). 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). 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. 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. 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. 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. 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. 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. 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 EXYNOSTM 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. 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. Figure 2 is a conceptual diagram showing the structure of a wireless local area network (WLAN). 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. 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. 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). 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. 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). 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). 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). The bottom of Figure 2 is a conceptual diagram showing IBSS. 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. Figure 3 is a diagram illustrating a general link setup process. 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. 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. 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. 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. 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. 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. 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. 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. Figure 4 illustrates one embodiment of a multi-link (ML). 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). 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. 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. 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. 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. FIG. 5 illustrates a PPDU (physical protocol data unit or physical layer (PHY) protocol data unit) transmitted / received by an STA of this specification. 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. 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. 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). 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. 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. 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). 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. 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}. 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. 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. 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. 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. 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". 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. 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. 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. 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. For example, the version-independent bits of U-SIG may include information about the length of a transmission opportunity (TXOP) and information about the BSS color ID. 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. For example, a U-SIG may include information about 1) a bandwidth field including information about a bandwidth, 2) a field including information about an MCS technique applied to the UHR-SIG, 3) an indication field including information about whether a dual subcarrier modulation (DCM) technique is applied to the UHR-SIG, 4) a field including information about the number of symbols used for the UHR-SIG, 5) a field including information about whether the 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 the UHR-LTF and the CP length. 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. 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. 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. 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). 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). 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. 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. 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). 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. 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. 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. 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. 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. Figure 7 is a diagram showing the layout of resource units (RUs) used for 40MHz PPDU. 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. 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. 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. Figure 9 illustrates an operation according to UL-MU. As illustrated, a transmitting STA (e.g., AP) can perform 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. 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. Figure 10 shows an example of channels used / supported / defined within the 2.4 GHz band. 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. 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. 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. Figure 11 illustrates an example of channels used / supported / defined within the 5 GHz band. 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. 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. 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. Figure 12 illustrates an example of channels used / supported / defined within the 6 GHz band. 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. 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. 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. Below, the structure and types / subtypes of MAC frames are described. 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. 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. 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. 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). 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). 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. The MAC frame / signal used in this specification can be identified through the type field / information and subtype field / information described above. For example, “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, and B4 bits in the frame control field are 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). FIG. 14 illustrates a modified example of a transmitting device and / or a receiving device of the present specification. 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. 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. 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. 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. 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). 1. Secondary channel This specification proposes a secondary channel access process, and first defines the primary channel and secondary channel as follows. The primary channel is a common operating channel for all STAs that are members of a BSS, and in a 20MHz, 40MHz, 80MHz, 160MHz, 80+80MHz or 320MHz BSS, the primary channel is the primary 20MHz channel. A secondary channel is a channel associated with a primary channel that is used to create a wider channel than the primary channel. In a 40MHz, 80MHz, 160MHz, 80+80MHz, or 320MHz BSS, the secondary channel is a secondary 20MHz channel. The secondary channel may also be referred to as a non-primary channel or a Non-Primary Channel Access (NPCA) primary channel. 2. How to perform Non-Primary Channel Access (NPCA) or Secondary Channel Access (SCA) 2.1 Problems with prior art Currently, 802.11 performs channel access based on the primary channel. That is, only when the primary channel is idle and the back-off counter (BC) reaches 0 can an STA transmit frames, including on the idle secondary channel. To this end, all STAs perform CCA (Clear Channel Assessment) with the primary channel as a priority. Accordingly, the AP announces the primary channel of the BSS and always includes the primary channel to transmit management frames such as beacons and probe response frames. This mechanism is effective for protection because frame exchange between all STAs and the AP is performed without interference. However, on the other hand, it is inefficient from a medium usage perspective because the idle secondary channel cannot be accessed when only the primary channel is BUSY. Figure 15 illustrates an example of channel access in an 802.11 wireless LAN system. Figure 15 shows channel access based on the primary channel in the 80MHz bandwidth. As shown in Figure 15, the following are referred to in this specification. P20: Primary 20MHz Channel S20: Secondary 20MHz Channel (when the bandwidth is 40MHz, it refers to the secondary channel of 20MHz excluding P20) S40: Secondary 40MHz Channel (when the bandwidth is 80MHz, it refers to the secondary channel of 40MHz excluding P20 / S20) S80: Secondary 80MHz Channel (when the bandwidth is 160MHz, it refers to the secondary channel of 80MHz excluding P20 / S20 / S40) S160: Secondary 160MHz Channel (when the bandwidth is 320MHz, it refers to the secondary channel of 160MHz excluding P20 / S20 / S40 / S80) S320: Secondary 320MHz Channel (when the bandwidth is 640MHz, it refers to the secondary channel of 320MHz excluding P20 / S20 / S40 / S80 / S160) If P20 is BUSY due to CCA or NAV (Network Allocation Vector), the BC is not reduced and waits until it becomes IDLE. When BC becomes 0 through this back-off process, the channel status of S20 and S40 is checked (i.e., CCA) and a frame is transmitted. In this example, since S40 is BUSY, the STA transmits a frame corresponding to a 40MHz PPDU through P20 and S20. As previously mentioned, when P20 is BUSY and S20 and S40 are IDLE, as shown in Figure 15, 60MHz of bandwidth is wasted, reducing medium utilization efficiency. Therefore, this specification proposes a method for accessing the secondary channel when P20 is BUSY. However, in an environment where the BSS Operating Bandwidth is 160 MHz and the secondary channel (referred to as SCA P20 in this specification) for performing back-off is located at S20, as shown in FIG. 19 described below, the PPDU bandwidth that can be generated is as follows. - 20MHz PPDU (utilizing SCA P20) - 80MHz PPDU (utilizing SCA P80) - 160MHz PPDU (utilizing SCA P160) At this time, it can be confirmed that 40MHz PPDU cannot be generated. The reason is as follows. Currently, 802.11be supports Preamble Puncturing, which transmits PPDU by puncturing some busy channels to maximize channel utilization. However, the puncturing pattern is not supported for 80MHz PPDU or lower. When transmitting 40MHz PPDU in secondary channel access, 40MHz PPDU is transmitted through SCA P40, but in the channel composition where SCA P20 is determined as S20 as shown in Fig. 19, 40MHz PPDU cannot be transmitted because SCA P40 includes busy P20. Considering the transmission of PPDUs with various bandwidths by applying the Preamble Puncturing Pattern defined in the existing 802.11be to secondary channel access, the puncturing patterns that can be applied when transmitting 80MHz and 160MHz PPDUs in Fig. 19 are as follows. - 80MHz PPDU: [x 1 1 1] - 160MHz PPDU: [x 1 1 1 1 1 1 1] Here, x represents a punctured 20MHz channel and 1 represents a non-punctured 20MHz channel. First, since P20 must always be punctured by default, we can see that only one puncturing pattern is supported, in which only P20 is punctured, when transmitting 80MHz and 160MHz PPDUs. In this case, if even one of the 20MHz slots other than P20 is busy, both the 80MHz and 160MHz PPDUs cannot transmit the PPDU, resulting in significant performance degradation in terms of channel utilization. In this specification, when deciding on a secondary channel to back-off (defined as SCA P20 in this specification), we propose a restriction rule for SCA P20 decision that can generate PPDUs with various bandwidth sizes and support various puncturing patterns defined in 802.11be, thereby obtaining gains in terms of channel utilization. The references (names) in this specification may change, and STA may include AP STA or non-AP STA. 2.2 Secondary channel access method 2.2.1 STA Capabilities for Secondary Channel Access Capabilities for Secondary Channel Access (SCA) can be defined, and STAs and APs can announce them. SCA capabilities can be determined by whether frames can be decoded by performing CCA (referred to as preamble detection (PD)) on the Secondary Channel (SCH). This allows NAVs to be set on the SCH as well. Originally, CCA could identify Wi-Fi frames performed on the Primary Channel (PCH). - Level 0: No Back-off on SCH: SCH performs CCA as before. That is, it performs CCA that can detect Wi-Fi signals (referred to as guard interval detection (GID)), CCA that detects signals above a certain strength (referred to as energy detection (ED)), etc. - Level 1: Back-off on a SCH at a time: This is a method of performing PD on only one secondary channel at a time. - Level 2: Back-off on SCHs at the same time: This is a method of performing PD on multiple secondary channels at the same time. These Capabilities can be included in UHR capabilities IE (Information Element) and transmitted as Beacon, Probe Response frame, (Re)Association Request frame from the AP perspective, and Probe Request frame, (Re)Association Request frame from the non-AP STA perspective. 2.2.2 Basic Procedure of Secondary Channel Access Basically, if an STA has Intra-BSS NAV set in the PCH, it is recommended not to perform SCA. For example, if an AP exchanges frames with an STA within the TXOP it acquired, the other STA will set an intra-BSS NAV based on the primary channel. At this time, if an STA with an intra-BSS NAV set accesses the SCH and transmits a frame to the AP, the AP will not receive the frame during Tx (e.g., DL Data, Ack, etc.). Therefore, it is recommended that an STA perform SCA only if the Basic NAV is set in the PCH. That is, STA can perform SCA when Basic NAV is set in PCH. Figure 16 illustrates an example of the basic procedure of SCA. Figure 16 illustrates the basic SCA process. If the Basic NAV is set while the STA is performing a backoff at P20, the backoff is performed at S20 at the time the NAV is set. (Switching delay may occur for the PD from P20 to S20 for the PD to S20.) This is a difference in the CCA method in that the CCA can be performed at S20, and can be performed at all levels. The reason for performing a backoff at S20 is that if a neighboring STA with the same or similar operation channel as this STA does not perform a backoff and is in an idle state and transmits a frame at the same time, a collision may occur, which may waste the channel. When performing SCA, considerations include: i) How to set TXOP - so that it ends before the Basic NAV expires Since CCA must be performed for P20 by default when Basic NAV expires on P20, the end time of TXOP on SCH is set so that TXOP ends before the time when Basic NAV expires. => If TXOP is set to end after the time when the Basic NAV expires, there is a problem that the STA cannot receive the frame because the Legacy STA, etc. can transmit the frame through P20 after the Basic NAV set for the STA. In addition, if the target beacon transmission time (TBTT) is set in the middle of the Basic NAV, the AP may have a problem because it must prepare to transmit the Beacon immediately after the Basic NAV, and non-AP STAs may not receive the Beacon that the AP should transmit in time and may wait for more time than the scheduled time. Therefore, the end time of the TXOP is set to a condition that it ends before the time when the Basic NAV expires, so that normal frame exchange can be performed in P20. => If there is not enough time to set the TXOP, the frame is not transmitted. In other words, if it is difficult to set the TXOP for the interval between the point when the Back-off counter (BC) in the SCH becomes 0 and the point when the Basic NAV in the PCH ends, the frame is not transmitted. For example, as in the example of Fig. 16, when performing a back-off at S20, the back-off counter becomes 0 and the TXOP is caught, the end is made earlier than the point at which the Basic NAV ends. ii) Frame transmission method - presence or absence of WaitTime Previously, when the backoff counter reached 0 via backoff on P20, frames could be transmitted via P20 and one or more idle SCHs, based on whether one or more SCHs were idle or busy. Therefore, SCA requires a change to the existing method to account for the BUSY state of P20. The backoff operation for this is as follows. - STA can perform back-off on one or more SCHs when P20 is BUSY. When P20 is busy, STA can perform back-off on S20 directly without a separate WaitTime after switching to S20. Additionally or alternatively, after switching to S20, STA can wait for the WaitTime before performing back-off on S20 and then perform back-off on S20. The reason is as follows. Several blindness issues may occur for SCA. Blindness issue means that the current situation occurring on the channel to be switched is not recognized. For example, when the first STA in power saving mode changes from doze to awake state, if the second STA, which is currently a hidden node (STA not within the transmission / reception range), transmits a frame to the third STA, which is within the transmission / reception range of the first STA, the first STA is not aware of this. Therefore, if the first STA transmits a frame, it may affect the third STA. Similarly, blindness issues that may arise with SCA include: - Case #1: When performing channel access by moving to SCH after Basic NAV is set in PCH - Case #2: After performing SCA in SCH, it moves to PCH and performs channel access. To resolve the issue above, the operation process is as follows when there is a WaitTime before performing a back-off. - First, each WaitTime can be defined. In this specification, Case #1 is referred to as SCHWaitTime, and Case #2 is referred to as PCHWaitTime. The AP can include this information in the Management frame, including the AP's Beacon and Probe Response, within the UHR Operation IE or in a new IE format. => Each WaitTime can be specified as a value with a certain unit (e.g., 32us, 64us). => Additionally or alternatively, WaitTime may vary for each SCH on which Back-off is performed. => Additionally or alternatively, it may vary depending on the Basic NAV value set in PCH. - If a frame / PPDU that can set NAV or a frame / PPDU addressed to the STA that started the Timer is received while each WaitTime is running, the WaitTime is terminated. - Back-off is not performed while each WaitTime is in operation, and STA can operate so that it can transmit frames such as RTS and MU-RTS when WaitTime becomes 0. - Additionally or alternatively, back-off is performed while WaitTime is running, and the STA can transmit frames such as RTS, MU-RTS, etc. => If frame transmissions continue to fail, it is necessary to limit the number of frame transmissions, such as RTS frames, for protection. Furthermore, persistent failures increase the CW, which can reduce transmission opportunities for channel access. Furthermore, continuous, unnecessary transmissions waste the channel. <SCA에 대한 STA의 동작과정 #1> - Here, STA can be a non-AP STA or an AP. In the present disclosure, an STA performing SCA may transmit frames / PPDUs on an SCH even during the time when a NAV is set on the PCH. For example, the STA may transmit frames (or PPDUs) excluding (or punctured) the PCH on one or more SCHs in an IDLE state, as determined by the backoff performed on one or more SCHs and the CCA results of one or more SCHs for which backoff has not been performed. Additionally or alternatively, the STA can perform back-off from S20 immediately after switching to S20 without a separate WaitTime. Additionally or alternatively, the STA may perform back-off to transmit a frame such as RTS or MU-RTS after switching to S20 and then after WaitTime ends (when WaitTime becomes 0) to resolve the blindness issue. => Additionally or alternatively, the STA may perform back-off while WaitTime is running and transmit frames such as RTS or MU-RTS. Additionally or alternatively, a TXOP initiated by transmission of a frame or PPDU on the SCH 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 or PPDU following the corresponding frame or PPDU (including the interframe gap (IFS)). 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 differently to all SCHs. In the present disclosure, an STA receiving a frame transmitted via SCA can perform frame detection on the SCH even during the time when the NAV is set in the PCH. For example, the STA may perform backoff on the SCH because there is a frame to be transmitted, or even when there is no frame to be transmitted, the STA may attempt to receive a frame addressed to itself on the SCA. In addition, the STA may perform NAV setting / resetting based on the value of the duration / ID field of the frame detected on the SCH. 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 differently to all SCHs. Figure 17 shows the basic Secondary Channel Access operation process of STA. Referring to Figure 17, the transmission process of STA is as follows. When an STA receives a PPDU containing a frame from another BSS, the (Basic) NAV is set on the Primary channel. The STA performs a backoff on one or more 20MHz Secondary channels. If the backoff counter reaches 0 on the Secondary channel on which the STA performed the backoff, it performs CCA on the other Secondary channels. The STA transmits the PPDU containing the frame using a bandwidth that includes the Secondary channel on which it performed the backoff and other Secondary channels that are IDLE as a result of performing the CCA. Referring to Figure 17, the STA's receiving process is as follows. When an STA receives a PPDU containing a frame from another BSS, a (Basic) NAV is set on the Primary channel. The STA performs a Back-off on one or more 20MHz Secondary channels. While performing a Back-off, the STA receives a PPDU containing one or more frames and determines whether the frame is addressed to the STA (i.e., determines whether the Receiver address of the frame is the MAC address of the STA). If the frame is addressed to the STA, the STA decodes the Frame body of the frame. If the frame is not addressed to the STA, the STA sets the NAV to the value of the Duration field of the MAC header of the frame. In addition, a new channel composition for secondary channel access must be defined, and a rule for which channel to utilize to transmit a frame in order to transmit a 20MHz / 40MHz / 80MHz PPDU and to perform back-off based on S20 as in Fig. 16 according to the newly defined channel composition must be defined in order to utilize secondary channel access. 2.2.3 Channel Composition of Secondary Channel Access In order to perform secondary channel access when Basic NAV is set in P20, back-off must be performed in one or more S20s as in P20. As mentioned above, rules can be defined for which channels to include and transmit frames with various bandwidths based on the secondary channel performing back-off according to the newly defined channel composition in secondary channel access. First, the meaning of the 40 / 80 / 160 / 320MHz channel set is as follows. In channelization, it means a set of 40 / 80 / 160 / 320MHz channels that are non-overlapping and consist of consecutive 20MHz units in ascending order from the lowest frequency to the highest frequency, that is, from a frequency perspective. Figure 18 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 320 MHz and SCA P20 is the fifth 20 MHz channel. In Fig. 18, when the BSS Operating Bandwidth is 320MHz-1, it can be confirmed that there are eight 40MHz channel sets, four 80MHz channel sets, two 160MHz channel sets, and one 320MHz channel set. For example, the first 80MHz channel set is composed of the first, second, third, and fourth 20MHz channels. Additionally, the second 80MHz channel set is composed of the fifth, sixth, seventh, and eighth 20MHz channels. Additionally or alternatively, to configure the BSS Operating Bandwidth to 320 MHz, there are two channelizations for the 320 MHz channel: 320 MHz-1 and 320 MHz-2. Accordingly, the 320 MHz-2 channelization also has the same channel composition as the 320 MHz-1 channelization, as shown in Fig. 18. The definitions of channels for secondary channel access are as follows: SCA P20: Secondary Channel Access This is the channel that serves as the basis for performing back-off for secondary channel access when Basic NAV is set on P20, the primary 20MHz channel. SCA S20: Secondary Channel Access Secondary 20MHz channel (refers to the remaining 20MHz channels excluding SCA P20, which is located in the same 40MHz channel set as SCA P20) SCA P40: Secondary Channel Access Primary 40MHz channel (refers to a 40MHz channel including SCA P20 and SCA S20) SCA S40: Secondary Channel Access Secondary 40MHz channel (refers to the remaining 40MHz channels excluding SCA P40, which is located in the same 80MHz channel set as SCA P40) SCA P80: Secondary Channel Access Primary 80MHz channel (referring to the 80MHz channel including SCA P40 and SCA S40) SCA S80: Secondary Channel Access Secondary 80MHz channel (refers to the remaining 80MHz channels excluding SCA P80, which is located in the same 160MHz channel set as SCA P80) SCA P160: Secondary Channel Access Primary 160MHz channel (refers to a 160MHz channel including SCA P80 and SCA S80) SCA S160: Secondary Channel Access Secondary 80MHz channel (refers to a 160MHz channel located in a different 160MHz channel set than SCA P160) SCA P320: Secondary Channel Access Primary 320MHz channel (refers to a 320MHz channel including SCA P160 and SCA S160) SCA S320: Secondary Channel Access Secondary 320MHz channel (refers to a 320MHz channel located in a different 320MHz channel set from SCA P320 when the BSS Operating Bandwidth is 640MHz or higher) In other words, channel configuration in secondary channel access varies depending on the BSS Operating Bandwidth and the location of the SCA P20. In other words, the entire channel can be configured based on the size of the BSS Operating Bandwidth and the 20MHz channel number of the SCA P20. An example of this can be illustrated as follows. Figure 19 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 160 MHz and SCA P20 is the second 20 MHz channel. Figure 19 shows the secondary channel access channel composition when the BSS Operating Bandwidth is 160MHz and SCA P20 is the second 20MHz channel. SCA P20 is the second channel in ascending order of frequency (including P20), from lowest to highest frequency. As can be seen in Figure 19, once SCA P20 is determined, SCA S20, SCA P40, SCA S40, SCA P80, SCA S80, and SCA P160 are determined accordingly. Figure 20 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 160 MHz and SCA P20 is the third 20 MHz channel. Figure 20 shows the secondary channel access channel composition when the BSS Operating Bandwidth is 160MHz and SCA P20 is the third 20MHz channel. SCA P20 is the third channel in ascending order of frequency (including P20), from lowest to highest frequency. As can be seen in Figure 20, once SCA P20 is determined, SCA S20, SCA P40, SCA S40, SCA P80, SCA S80, and SCA P160 are determined accordingly. Figure 21 illustrates an example of a channel configuration for a Secondary Channel Access Channel when the BSS Operating Bandwidth is 160 MHz and SCA P20 is the fifth 20 MHz channel. Figure 21 shows the secondary channel access channel composition when the BSS Operating Bandwidth is 160MHz and SCA P20 is the fifth 20MHz channel. SCA P20 is the fifth channel in ascending order of frequency (including P20), from lowest to highest frequency. As can be seen in Figure 21, once SCA P20 is determined, SCA S20, SCA P40, SCA S40, SCA P80, SCA S80, and SCA P160 are determined accordingly. Figure 22 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 320 MHz and SCA P20 is the second 20 MHz channel. Figure 22 shows the secondary channel access channel composition when the BSS Operating Bandwidth is 320 MHz and SCA P20 is the second 20 MHz channel. SCA P20 is the second channel in ascending order from the lowest frequency to the highest frequency, i.e., in terms of frequency (including P20). As can be seen in Figure 22, when SCA P20 is determined, SCA S20, SCA P40, SCA S40, SCA P80, SCA S80, SCA P160, and SCA P320 are determined accordingly. Additionally or alternatively, accordingly, 320 MHz-1 channelization also has the same channel composition as 320 MHz-2 channelization, as shown in Figure 22. Figure 23 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 320 MHz and SCA P20 is the third 20 MHz channel. Figure 23 shows the secondary channel access channel composition when the BSS Operating Bandwidth is 320 MHz and SCA P20 is the third 20 MHz channel. SCA P20 is the third channel in ascending order from the lowest frequency to the highest frequency, i.e., in terms of frequency (including P20). As can be seen in Figure 23, when SCA P20 is determined, SCA S20, SCA P40, SCA S40, SCA P80, SCA S80, SCA P160, and SCA P320 are determined accordingly. Additionally or alternatively, accordingly, 320 MHz-1 channelization also has the same channel composition as 320 MHz-2 channelization, as shown in Figure 23. Figure 24 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 320 MHz and SCA P20 is the ninth 20 MHz channel. Figure 24 shows the secondary channel access channel composition when the BSS Operating Bandwidth is 320 MHz and SCA P20 is the ninth 20 MHz channel. SCA P20 is the ninth channel in ascending order from the lowest frequency to the highest frequency, i.e., in terms of frequency (including P20). As can be seen in Figure 24, when SCA P20 is determined, SCA S20, SCA P40, SCA S40, SCA P80, SCA S80, SCA P160, and SCA P320 are determined accordingly. Additionally or alternatively, accordingly, 320 MHz-1 channelization also has the same channel composition as 320 MHz-2 channelization, as shown in Figure 24. 2.2.4 Wide Bandwidth Frame Transmission for Secondary Channel Access Based on the SCA P20 that performs back-off by applying the newly defined secondary channel access channel composition above, the rules for which channels to include for frame transmission can be defined as follows. Additionally or alternatively, before transmitting the frame, physical CCA and virtual CCA (NAV setting) are performed in the SCA P20 as in the existing P20. If the SCA P20 is BUSY due to CCA or NAV, the STA does not reduce the BC and waits until it becomes IDLE. On the other hand, if the SCA P20 is IDLE, the BC is reduced, and before the BC becomes 0, a second type of CCA is performed on other SCHs than the SCA P20 that performed back-off for a certain period of time (e.g., PIFS) to determine whether the channel is IDLE or BUSY. Depending on the determination, a wide bandwidth frame is transmitted in the secondary channel access as follows. 20MHz PPDU: Transmit PPDU including SCA P20 40MHz PPDU: Transmit PPDU including SCA P40 80MHz PPDU: PPDU transmission including SCA P80 160MHz PPDU: PPDU transmission including SCA P160 320MHz PPDU: PPDU transmission including SCA P320 When transmitting a PPDU, if a puncturing pattern is supported for a busy channel based on the results of the aforementioned CCA, the channel is transmitted including a signaling that it has been punctured. In the table below, in the puncturing pattern for a PPDU below 160 MHz, 1 means that the 20 MHz channel is not punctured, and x means that the 20 MHz channel is punctured. On the other hand, in the puncturing pattern for a PPDU below 320 MHz, 1 means that the 40 MHz channel is not punctured, and x means that the 40 MHz channel is punctured. Each is described in ascending order from lowest to highest in terms of frequency. PPDU bandwidthCasesPuncturing pattern (RU or MRU Index)Field value20 MHzNo puncturing[1](242-tone RU 1)040 MHzNo puncturing

[0011] (484-tone RU 1)080 MHzNo puncturing[1 1 1 1](996-tone RU 1)020 MHz puncturing[x 1 1 1](484+242-tone MRU 1)1[1 x 1 1](484+242-tone MRU 2)2[1 1 x 1](484+242-tone MRU 3)3[1 1 1 x](484+242-tone MRU 4)4 PPDU bandwidthCasesPuncturing pattern (RU or MRU Index)Field value160 MHzNo puncturing[1 1 1 1 1 1 1 1](2x996-tone RU 1)020 MHz puncturing[x 1 1 1 1 1 1 1](996+484+242-tone MRU 1)1[1 x 1 1 1 1 1 1](996+484+242-tone MRU 2)2[1 1 x 1 1 1 1 1](996+484+242-tone MRU 3)3[1 1 1 x 1 1 1 1](996+484+242-tone MRU 4)4[1 1 1 1 x 1 1 1](996+484+242-tone MRU 5)5[1 1 1 1 1 x 1 1](996+484+242-tone MRU 6)6[1 1 1 1 1 1 x 1](996+484+242-tone MRU 7)7[1 1 1 1 1 1 1 x](996+484+242-tone MRU 1)840 MHz puncturing[x x 1 1 1 1 1 1](996+484-tone MRU 1)9[1 1 x x 1 1 1 1](996+484-tone MRU 2)10[1 1 1 1 x x 1 1](996+484-tone MRU 3)11[1 1 1 1 1 1 x x](996+484-tone MRU 4)12 PPDU bandwidthCasesPuncturing pattern (RU or MRU Index)Field value320 MHzNo puncturing[1 1 1 1 1 1 1 1](4x996-tone RU 1)040 MHz puncturing[x 1 1 1 1 1 1 1](3x996+484-tone MRU 1)1[1 x 1 1 1 1 1 1](3x996+484-tone MRU 2)2[1 1 x 1 1 1 1 1](3x996+484-tone MRU 3)3[1 1 1 x 1 1 1 1](3x996+484-tone MRU 4)4[1 1 1 1 x 1 1 1](3x996+484-tone MRU 5)5[1 1 1 1 1 x 1 1](3x996+484-tone MRU 6)6[1 1 1 1 1 1 x 1](3x996+484-tone MRU 7)7[1 1 1 1 1 1 1 x](3x996+484-tone MRU 1)880 MHz puncturing[x x 1 1 1 1 1 1](3x996-tone MRU 1)9[1 1 x x 1 1 1 1](3x996-tone MRU 2)10[1 1 1 1 x x 1 1](3x996-tone MRU 3)11[1 1 1 1 1 1 x x](3x996-tone MRU 4)12 PPDU bandwidthCasesPuncturing pattern (RU or MRU Index)Field value320 MHzConcurrent 80 MHz and40 MHz puncturing[xxx 1 1 1 1 1](2x996+484-tone MRU 7)13[xx 1 x 1 1 1 1](2x996+484-tone MRU 8)14[xx 1 1 x 1 1 1](2x996+484-tone MRU 9)15[xx 1 1 1 1 MRU 12)18[x 1 1 1 1 1 xx](2x996+484-tone MRU 1)19[1 x 1 1 1 1 xx](2x996+484-tone MRU 2)20[1 1 xx](2x996+484-tone MRU 4)22[1 1 1 1 x 1 xx](2x996+484-tone MRU 5)23[1 1 1 1 1 xxx](2x996+484-tone MRU 6)24 Figure 25 illustrates an example of transmitting a Wide Bandwidth Frame in Secondary Channel Access when the BSS Operating Bandwidth is 160 MHz and SCA P20 is the second 20 MHz channel. Figure 25 shows an example of wide bandwidth frame transmission using secondary channel access when the channel composition of Figure 19 is used. The dotted rectangle in Figure 25 indicates that the PPDU has been punctured. When P20 is busy, the STA or AP performs backoff based on SCA P20 to transmit the frame. As can be seen in Figure 25, when transmitting PPDUs with different bandwidth sizes, the channel composition differs depending on the position of SCA S20, but PPDUs with various bandwidths can be transmitted according to the PPDU transmission rules defined above. First, when the backoff counter value of SCA P20 becomes 0, the channel status is checked (i.e., CCA) for the remaining secondary 20MHz channels and the frame is transmitted. When transmitting a 20MHz PPDU, the PPDU is transmitted including only SCA P20. Next, when transmitting an 80MHz PPDU, the PPDU is transmitted including SCA P80, which is a combination of SCA P40 and SCA S40. If P20 is included in SCA P80, the 80MHz PPDU is transmitted including signaling that P20 has been punctured. When transmitting a 160MHz PPDU, the PPDU is transmitted including SCA P160, which is a combination of SCA P80 and SCA S80. At this time, since P20 is busy, in this case, the 160MHz PPDU is transmitted including signaling that P20 has been punctured. In this way, according to the previously defined rule, when transmitting a PPDU of 80MHz or higher, if P20 is included, the PPDU is transmitted including signaling that P20 has been punctured. Figure 26 illustrates an example of transmitting a Wide Bandwidth Frame in Secondary Channel Access when the BSS Operating Bandwidth is 160 MHz and SCA P20 is the third 20 MHz channel. Figure 26 shows an example of wide bandwidth frame transmission using secondary channel access when the channel composition of Figure 20 is used. First, when the back-off counter value of SCA P20 becomes 0, the channel status is checked (i.e., CCA) for the remaining secondary 20MHz channels and the frame is transmitted. When transmitting a 20MHz PPDU, the PPDU is transmitted by including only SCA P20. When transmitting a 40MHz PPDU, the PPDU is transmitted by utilizing SCA P40, which is a combination of SCA P20 and SCA S20. Next, when transmitting an 80 / 160MHz PPDU, since P20 is included in the 80 / 160MHz PPDU, the PPDU is transmitted by including signaling that P20 has been punctured. Figure 27 illustrates an example of transmitting a Wide Bandwidth Frame in Secondary Channel Access when the BSS Operating Bandwidth is 160 MHz and SCA P20 is the fifth 20 MHz channel. Figure 27 shows an example of wide bandwidth frame transmission using secondary channel access when the channel composition of Figure 21 is used. First, when the back-off counter value of SCA P20 becomes 0, the channel status is checked (i.e., CCA) for the remaining secondary 20MHz channels and the frame is transmitted. Based on the rule mentioned above, it can be confirmed that 20 / 40 / 80MHz PPDUs are transmitted. When transmitting a 160MHz PPDU, since P20 is included in the 160MHz PPDU, the PPDU is transmitted including signaling that P20 has been punctured. That is, in this embodiment, CCA is performed on SCHs other than SCA P20 that performed back-off, and a wide bandwidth frame is transmitted for an IDLE channel, and a signaling indicating that puncturing has been included in the transmission for a busy channel. 2.2.5 Restriction Rule for Determining Back-off Secondary Channel for Secondary Channel Access When performing Secondary Channel Access, the bandwidth size of the PPDU that can be transmitted can vary depending on the channel selected for SCA P20, and whether or not support for various puncturing patterns defined in 802.11be can vary when transmitting PPDUs. Accordingly, the decision regarding SCA P20 affects channel utilization. This specification proposes a restriction rule for SCA P20 decision that can achieve gains in channel utilization. Case 1) BSS Operating Bandwidth is 160MHz Case 1-1) When SCA P20 is located at S20 (Fig. 19) As mentioned earlier, the possible PPDU bandwidths are as follows: - 20MHz PPDU (utilizing SCA P20) - 80MHz PPDU (utilizing SCA P80) At this time, the available Puncturing Pattern is 1, as follows: (x is a punctured 20MHz CH (channel), 1 is a non-punctured 20MHz CH) [x 1 1 1] That is, if even one of the three remaining 20MHz channels excluding P20 is busy, an issue occurs in which 80MHz PPDU cannot be generated. - 160MHz PPDU (utilizing SCA P160) At this time, the available Puncturing Pattern is 1, as follows: (x is a punctured 20MHz CH, 1 is a non-punctured 20MHz CH) [x 1 1 1 1 1 1 1] That is, if even one of the seven 20MHz channels excluding P20 is busy, an issue occurs in which 160MHz PPDU cannot be generated. Case 1-2) When SCA P20 is located at S40 (Fig. 20) In this case, the creatable PPDU bandwidth is as follows: - 20MHz PPDU (utilizing SCA P20) - 40MHz PPDU (utilizing SCA P40) In Case 1-1), 40MHz PPDU cannot be generated, but in Case 1-2), 40MHz PPDU can be generated using SCA P40. - 80MHz PPDU (utilizing SCA P80) At this time, the available Puncturing Pattern is 1, as follows: (x is a punctured 20MHz CH, 1 is a non-punctured 20MHz CH) [x 1 1 1] That is, if even one of the three remaining 20MHz channels excluding P20 is busy, an issue occurs in which 80MHz PPDU cannot be generated. - 160MHz PPDU (utilizing SCA P160) At this time, there are two available puncturing patterns as follows: (x is a punctured 20MHz CH, 1 is a non-punctured 20MHz CH) [x 1 1 1 1 1 1 1] [xx 1 1 1 1 1 1] That is, when transmitting 160MHz PPDU compared to Case 1-1), performance gain in terms of channel utilization can be obtained by supporting more puncturing patterns. Case 1-3) When SCA P20 is located at S80 (Fig. 21) In this case, the creatable PPDU bandwidth is as follows: - 20MHz PPDU (utilizing SCA P20) - 40MHz PPDU (utilizing SCA P40) In Case 1-1), 40MHz PPDU cannot be generated, but in Case 1-2) and Case 1-3), 40MHz PPDU can be generated using SCA P40. - 80MHz PPDU (utilizing SCA P80) At this time, there are four available puncturing patterns as follows. (x is a punctured 20MHz CH, 1 is a non-punctured 20MHz CH) [1 1 1 1] (No Puncturing) [1 x 1 1] [1 1 x 1] [1 1 1 x] Since SCA P20 exists in S80, P20 is not included in PPDU transmission, and thus more puncturing patterns are supported compared to case 1-1) and case 1-2). Compared to case 1-1) and case 1-2), by supporting more puncturing patterns when transmitting 80MHz PPDU, a performance gain in terms of channel utilization can be obtained. - 160MHz PPDU (utilizing SCA P160) At this time, the available puncturing patterns are as follows. (x is a punctured 20MHz CH, 1 is a non-punctured 20MHz CH) [x 1 1 1 1 1 1 1] [xx 1 1 1 1 1 1] That is, when transmitting 160MHz PPDU compared to Case 1-1), performance gain in terms of channel utilization can be obtained by supporting more puncturing patterns. When analyzing the creatable PPDU bandwidth and available Puncturing Pattern according to the location of SCA P20 in Case 1), it can be confirmed that if the BSS Operating Bandwidth is 160MHz, locating SCA P20 at S80 can obtain the most efficient result in terms of channel utilization. Case 2) BSS Operating Bandwidth is 320MHz Case 2-1) When SCA P20 is located at S20 (Fig. 22) As mentioned earlier, the possible PPDU bandwidths are as follows: - 20MHz PPDU (utilizing SCA P20) - 80MHz PPDU (utilizing SCA P80) At this time, the available Puncturing Pattern is 1, as follows: (x is a punctured 20MHz CH, 1 is a non-punctured 20MHz CH) [x 1 1 1] That is, if even one of the three remaining 20MHz channels excluding P20 is busy, an issue occurs in which 80MHz PPDU cannot be generated. - 160MHz PPDU (utilizing SCA P160) At this time, the available Puncturing Pattern is 1, as follows: (x is a punctured 20MHz CH, 1 is a non-punctured 20MHz CH) [x 1 1 1 1 1 1 1] That is, if even one of the seven 20MHz channels excluding P20 is busy, an issue occurs in which 160MHz PPDU cannot be generated. Case 2-2) When SCA P20 is located at S40 (Fig. 23) In this case, the creatable PPDU bandwidth is as follows: - 20MHz PPDU (utilizing SCA P20) - 40MHz PPDU (utilizing SCA P40) In Case 1-1), 40MHz PPDU cannot be generated, but in Case 1-2), 40MHz PPDU can be generated using SCA P40. - 80MHz PPDU (utilizing SCA P80) At this time, the available Puncturing Pattern is 1, as follows: (x is a punctured 20MHz CH, 1 is a non-punctured 20MHz CH) [x 1 1 1] That is, if even one of the three remaining 20MHz channels excluding P20 is busy, an issue occurs in which 80MHz PPDU cannot be generated. - 160MHz PPDU (utilizing SCA P160) At this time, there are two available puncturing patterns as follows: (x is a punctured 20MHz CH, 1 is a non-punctured 20MHz CH) [x 1 1 1 1 1 1 1] [xx 1 1 1 1 1 1] That is, when transmitting 160MHz PPDU compared to Case 2-1), performance gain in terms of channel utilization can be obtained by supporting more puncturing patterns. - 320MHz PPDU (utilizing SCA P320) At this time, there are two available puncturing patterns as follows: (x is a punctured 40MHz CH, 1 is a non-punctured 40MHz CH) [x 1 1 1 1 1 1 1] [x 1 1 1 1 1 xx] That is, in Case 2-1), 320MHz PPDU cannot be generated, but in Case 2-2), 320MHz PPDU can be generated using SCA P320, so performance gain in terms of channel utilization can be obtained. Case 2-3) When SCA P20 is located at S80 (Fig. 18) In this case, the creatable PPDU bandwidth is as follows: - 20MHz PPDU (utilizing SCA P20) - 40MHz PPDU (utilizing SCA P40) In Case 2-1), 40MHz PPDU cannot be generated, but in Case 2-2) and Case 2-3), 40MHz PPDU can be generated using SCA P40. - 80MHz PPDU (utilizing SCA P80) At this time, there are four available puncturing patterns as follows. (x is a punctured 20MHz CH, 1 is a non-punctured 20MHz CH) [1 1 1 1] (No Puncturing) [1 x 1 1] [1 1 x 1] [1 1 1 x] Since SCA P20 exists in S80, P20 is not included in PPDU transmission, and thus more Puncturing Patterns are supported compared to case 2-1) and case 2-2). In other words, compared to case 2-1) and case 2-2), by supporting more Puncturing Patterns when transmitting 80MHz PPDU, a performance gain in terms of channel utilization can be obtained. - 160MHz PPDU (utilizing SCA P160) At this time, there are two available puncturing patterns as follows: (x is a punctured 20MHz CH, 1 is a non-punctured 20MHz CH) [x 1 1 1 1 1 1 1] [xx 1 1 1 1 1 1] That is, when transmitting 160MHz PPDU compared to Case 2-1), performance gain in terms of channel utilization can be obtained by supporting more puncturing patterns. - 320MHz PPDU (utilizing SCA P320) At this time, there are 8 available puncturing patterns as follows. (x is a punctured 40MHz CH, 1 is a non-punctured 40MHz CH) [x 1 1 1 1 1 1 1] [x 1 1 1 1 1 xx] [xx 1 1 1 1 1 1] [xx 1 x 1 1 1 1] [xx 1 1 x 1 1 1] [xx 1 1 1 x 1 1] [xx 1 1 1 1 x 1] [xx 1 1 1 1 1 x] That is, in Case 2-1), 320MHz PPDU cannot be generated, but in Case 2-2) and Case 2-3), 320MHz PPDU can be generated using SCA P320. In addition, in Case 2-3), compared to Case 2-2), performance gain in terms of channel utilization can be obtained by supporting more Puncturing Patterns when transmitting 320MHz PPDU. Case 2-4) When SCA P20 is located at S160 (Fig. 24) In this case, the creatable PPDU bandwidth is as follows: - 20MHz PPDU (utilizing SCA P20) - 40MHz PPDU (utilizing SCA P40) In Case 2-1), 40MHz PPDU cannot be generated, but in Case 2-2), Case 2-3), and Case 2-4), 40MHz PPDU can be generated using SCA P40. - 80MHz PPDU (utilizing SCA P80) At this time, there are four available puncturing patterns as follows. (x is a punctured 20MHz CH, 1 is a non-punctured 20MHz CH) [1 1 1 1] (No Puncturing) [1 x 1 1] [1 1 x 1] [1 1 1 x] Since SCA P20 exists in S80, P20 is not included in PPDU transmission, and thus more Puncturing Patterns are supported compared to case 2-1) and case 2-2). In other words, compared to case 2-1) and case 2-2), by supporting more Puncturing Patterns when transmitting 80MHz PPDU, a performance gain in terms of channel utilization can be obtained. - 160MHz PPDU (utilizing SCA P160) At this time, there are 7 available puncturing patterns as follows. (x is a punctured 20MHz CH, 1 is a non-punctured 20MHz CH) [1 1 1 1 1 1 1 1] (No Puncturing) [1 x 1 1 1 1 1 1] [1 1 x 1 1 1 1 1] [1 1 1 x 1 1 1 1] [1 1 1 1 x 1 1 1] [1 1 1 1 1 x 1 1] [1 1 1 1 1 1 x 1] [1 1 1 1 1 1 1 x] That is, when transmitting 160MHz PPDU, a performance gain in terms of channel utilization can be obtained by supporting more puncturing patterns than in Case 2-1), Case 2-2), and Case 2-3). - 320MHz PPDU (utilizing SCA P320) At this time, there are 8 available puncturing patterns as follows. (x is a punctured 40MHz CH, 1 is a non-punctured 40MHz CH) [x 1 1 1 1 1 1 1] [x 1 1 1 1 1 xx] [xx 1 1 1 1 1 1] [xx 1 x 1 1 1 1] [xx 1 1 1 x 1 1] [xx 1 1 1 1 x 1] [xx 1 1 1 1 1 x] [xxx 1 1 1 1 1] That is, in Case 2-1), 320MHz PPDU cannot be generated, but in Case 2-2), Case 2-3), and Case 2-4), 320MHz PPDU can be generated using SCA P320. In addition, in Case 2-3) and Case 2-4), compared to Case 2-1) and Case 2-2), more Puncturing Patterns are supported when transmitting 320MHz PPDU, thereby achieving performance gain in terms of channel utilization. When analyzing the creatable PPDU bandwidth and available Puncturing Pattern according to the location of SCA P20 in Case 2), it can be confirmed that if the BSS Operating Bandwidth is 320MHz, locating SCA P20 at S160 can obtain the most efficient result in terms of channel utilization. Figure 28 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 80 MHz and SCA P20 is the second 20 MHz channel. Figure 29 illustrates an example of a channel configuration for Secondary Channel Access when the BSS Operating Bandwidth is 80 MHz and SCA P20 is the third 20 MHz channel. Case 3) BSS Operating Bandwidth is 80MHz Case 1-1) When SCA P20 is located at S20 (Fig. 28) As mentioned earlier, the possible PPDU bandwidths are as follows: - 20MHz PPDU (utilizing SCA P20) - 80MHz PPDU (utilizing SCA P80) At this time, the available Puncturing Pattern is 1, as follows: (x is a punctured 20MHz CH, 1 is a non-punctured 20MHz CH) [x 1 1 1] That is, if even one of the three remaining 20MHz channels excluding P20 is busy, an issue occurs in which 80MHz PPDU cannot be generated. Case 1-2) When SCA P20 is located at S40 (Fig. 29) In this case, the creatable PPDU bandwidth is as follows: - 20MHz PPDU (utilizing SCA P20) - 40MHz PPDU (utilizing SCA P40) In Case 1-1), 40MHz PPDU cannot be generated, but in Case 1-2), 40MHz PPDU can be generated using SCA P40. - 80MHz PPDU (utilizing SCA P80) At this time, the available Puncturing Pattern is 1, as follows: (x is a punctured 20MHz CH, 1 is a non-punctured 20MHz CH) [x 1 1 1] That is, if even one of the three remaining 20MHz channels excluding P20 is busy, an issue occurs in which 80MHz PPDU cannot be generated. When analyzing the creatable PPDU bandwidth and available Puncturing Pattern according to the location of SCA P20 in Case 3), it can be confirmed that if the BSS Operating Bandwidth is 80MHz, locating SCA P20 at S40 can achieve the most efficient results in terms of channel utilization. That is, through the analysis of Case 1), Case 2), and Case 3) described above, when determining SCA P20 within the BSS Operating Bandwidth, it can be confirmed that the following gives the best performance in terms of channel utilization: i) determining SCA P20 within the Secondary 40MHz when the BSS Operating Bandwidth is 80MHz, ii) determining SCA P20 within the Secondary 80MHz when the BSS Operating Bandwidth is 160MHz, and iii) determining SCA P20 within the Secondary 160MHz when the BSS Operating Bandwidth is 320MHz. If the restriction rule is generalized, it can be expressed as SCA P20 being located in the secondary channel corresponding to half the size of the BSS operating bandwidth. Even when the BSS Operating Bandwidth is 640MHz, the above restriction rule for SCA P20 determination is applied to determine the bandwidth size of PPDU and whether to support various Puncturing Patterns. <SCA에 대한 STA의 동작과정 #2> - STA can be a non-AP STA or an AP In the present disclosure, an STA performing SCA may transmit a frame / PPDU on an SCH even during the time when a NAV is set on the PCH. For example, the STA may transmit a frame or PPDU excluding (or puncturing) the PCH on one or more SCHs in an IDLE state, as determined by the backoff performed on one or more SCHs and the CCA results of one or more SCHs on which the backoff is not performed. Additionally or alternatively, the STA can perform back-off from S20 immediately after switching to S20 without a separate WaitTime. Additionally or alternatively, the STA may perform back-off to transmit a frame such as RTS or MU-RTS after switching to S20 and then after WaitTime ends (when WaitTime becomes 0) to resolve the blindness issue. => Additionally or alternatively, the STA may perform back-off while WaitTime is running and transmit frames such as RTS or MU-RTS. Additionally or alternatively, a TXOP initiated by transmitting a frame or PPDU on the SCH 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 or PPDU following the corresponding frame or PPDU (including the interframe gap (IFS)). 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 differently to all SCHs. Additionally or alternatively, if the remaining SCH(s) except SCA P20 are determined to be BUSY based on the CCA result as in FIG. 25, the STA transmits a frame / PPDU through SCA P20. Additionally or alternatively, when SCA S80 and P20 are BUSY as in FIG. 25, the STA transmits a frame / PPDU via SCA P80 including signaling that P20 is punctured. Additionally or alternatively, if only P20 is BUSY as in Fig. 25, the STA transmits a frame / PPDU via SCA P160 including signaling that P20 is punctured. Additionally or alternatively, when the STA determines the S20 to perform back-off so that the P20 can perform SCA in a BUSY situation, the STA may determine the S20 to perform back-off (SCA P20) from the S40 when the BSS Operating Bandwidth is 80MHz. Additionally or alternatively, when the STA determines the S20 to perform back-off so that the P20 can perform SCA in a BUSY situation, the STA may determine the S20 to perform back-off (SCA P20) from the S80 when the BSS Operating Bandwidth is 160MHz. Additionally or alternatively, when the STA determines the S20 to perform back-off so that the P20 can perform SCA in a BUSY situation, the STA may determine the S20 to perform back-off (SCA P20) at S160 when the BSS Operating Bandwidth is 320MHz. In the present disclosure, an STA receiving a frame transmitted via SCA can perform frame detection on the SCH even during the time when the NAV is set in the PCH. For example, the STA may perform backoff on the SCH because there is a frame to be transmitted, or may attempt to receive a frame addressed to itself on the SCA even when there is no frame to be transmitted. In addition, the STA may perform NAV setting / resetting based on the value of the duration / ID field of the frame detected on the SCH. 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 differently to all SCHs. The PPDU in which the signal of this specification is transmitted / received may include a data field. The above data field contains user data and may contain packets for upper layers, i.e., may contain MPDU (MAC Frame). For example, the duration / ID field in the MAC header included in the MPDU may be set to a value including the time length of the frame exchange following the frame or PPDU transmitted excluding (or puncturing) the PCH when supporting channel access operation on the secondary channel. For example, the TXOP end time determined based on the value of the duration / ID field may be set before the end time of the NAV set on the primary channel. Additionally, as shown in the above drawing 1, the transmitting device and the receiving device may each include a memory, a processor, and a transceiver. The above memory can store information regarding a plurality of Secondary Channel Accesses described herein. The processor can perform back-off in the secondary channel based on the information stored in the memory, generate various RUs, and configure PPDUs. The processor can be configured as described in this specification.<SCA에 대한 STA의 동작과정 #1> ,<SCA에 대한 STA의 동작과정 #2> Can be set to do all / some. In particular, the transceiver (113) of the transmitting device includes an antenna and can perform analog signal processing. Specifically, the processor (111) can control the transceiver (113) to transmit a PPDU generated by the processor (111). Alternatively, the processor (111) may generate a transmission PPDU and store information about the transmission PPDU in the memory (112). For example, the processor (111) of the transmitting device may be configured to perform the operation of the transmitting STA according to the example of the present disclosure. For example, the processor (111) may be configured to transmit a frame on the SCH through the transceiver (113) during a time period in which a NAV is set on the PCH. For example, the processor (111) may be configured to perform a backoff on the SCH through the transceiver (113) and determine one or more SCHs in an IDLE state. For example, the processor (111) may be configured to transmit a frame / PPDU with the PCH excluded / punctured through the transceiver (113) on one or more SCHs. Additionally or alternatively, the processor (111) may be configured to generate a frame including a duration / ID field set to a value such that a TXOP starting with a frame / PPDU transmission on the SCH ends before the time point at which the NAV on the PCH ends. Additionally, the transceiver (123) of the receiving device can receive a PPDU based on the control of the processor (121). For example, the transceiver (123) can include a plurality of detailed units (not shown). For example, the transceiver (123) can include at least one receiving antenna and a filter for the corresponding receiving antenna. A PPDU received through a transceiver (123) may be stored in a memory (122). A processor (121) may process decoding of the received PPDU through the memory (122). The processor (121) may obtain control information (e.g., SIG) regarding BW / Tone-Plan / RU included in the PPDU and store the obtained control information in the memory (122). The processor (121) can perform decoding on the received PPDU. In addition, the processor (121) can process the decoded data. For example, the processor (121) can perform a processing operation to transmit information about the decoded data field to a higher layer (e.g., MAC layer). In addition, if the generation of a signal is instructed from the higher layer to the PHY layer in response to the data transmitted to the higher layer, a subsequent operation can be performed. For example, the processor parses a MAC PDU obtained through PHY decoding of the DATA field of a PPDU received through a transceiver. For example, the processor (121) of the receiving device may be configured to perform the operations of the receiving STA according to the examples of the present disclosure. For example, the processor (121) may attempt to detect a frame on the SCH via the transceiver (123) during the time for which the NAV is set on the PCH. The processor (121) may be configured to decode / parse a frame addressed to it based on a frame received on the SCH. Additionally, the processor (121) may be configured to set / reset the NAV based on the value of the duration / ID field of a frame not addressed to it. Figure 30 is a flowchart illustrating the operation of a transmitting device according to the present embodiment. An example of FIG. 30 may be performed at a transmitting STA or transmitting device (AP and / or non-AP STA). Some of the steps (or detailed sub-steps described below) in the example of Figure 30 may be omitted or changed. Through step S3010, the transmitting device (transmitting STA) can obtain information regarding the aforementioned Tone Plan. As described above, the information regarding the Tone Plan includes the size and location of the RU, control information related to the RU, information regarding the frequency band in which the RU is included, information regarding the STA receiving the RU, etc. Through step S3020, the transmitting device can configure / generate a PPDU based on the acquired control information. The step of configuring / generating the PPDU may include a step of configuring / generating each field of the PPDU. That is, step S3020 may include a step of configuring an EHT-SIG field including control information regarding a Tone Plan. That is, step S3020 may include a step of configuring a field including control information indicating the size / position of an RU (e.g., an N bitmap) and / or a step of configuring a field including an identifier (e.g., an AID) of an STA receiving the RU. Additionally, step S3020 may include a step of generating an STF / LTF sequence to be transmitted through a specific RU. The STF / LTF sequence may be generated based on a preset STF generation sequence / LTF generation sequence. Additionally, step S3020 may include a step of generating a data field (i.e., MPDU) to be transmitted via a specific RU. The transmitting device can transmit the PPDU configured through step S3020 to the receiving device based on step S3030. While performing step S3030, the transmitting device may perform at least one of operations such as CSD, Spatial Mapping, IDFT / IFFT operation, and GI insertion. A signal / field / sequence configured according to this specification can be transmitted in the form of FIG. 5. Figure 31 is a flowchart illustrating the operation of a receiving device according to the present embodiment. The above-described PPDU can be received according to an example of FIG. 31. An example of FIG. 31 may be performed at a receiving STA or receiving device (AP and / or non-AP STA). Some of the steps (or detailed sub-steps described below) in the example of Fig. 31 may be omitted. A receiving device (receiving STA) may receive all or part of a PPDU through step S3110. The received signal may have the form of FIG. 5. The sub-step of step S3110 can be determined based on step S3030 of Fig. 30. That is, step S3110 can perform an operation to restore the results of the CSD, Spatial Mapping, IDFT / IFFT operations, and GI insert operations applied in step S3030. At step S3120, the receiving device can decode all or part of the PPDU. Additionally, the receiving device can obtain control information related to the Tone Plan (i.e., RU) from the decoded PPDU. More specifically, the receiving device can decode the L-SIG and EHT-SIG of the PPDU based on the Legacy STF / LTF and obtain information included in the L-SIG and EHT SIG fields. Information regarding various Tone Plans (i.e., RUs) described herein can be included in the EHT-SIG, and the receiving STA can obtain information regarding the Tone Plan (i.e., RU) through the EHT-SIG. In step S3130, the receiving device can decode the remaining portion of the PPDU based on the information about the Tone Plan (i.e., RU) acquired through step S3120. For example, the receiving STA can decode the STF / LTF field of the PPDU based on the information about one Plan (i.e., RU). In addition, the receiving STA can decode the data field of the PPDU based on the information about the Tone Plan (i.e., RU) and acquire the MPDU included in the data field. Additionally, the receiving device may perform a processing operation to transmit the decoded data to a higher layer (e.g., MAC layer) through step S3130. Additionally, if the generation of a signal is instructed from the higher layer to the PHY layer in response to the data transmitted to the higher layer, a subsequent operation may be performed. Hereinafter, the above-described embodiment will be described with reference to FIGS. 1 to 31. FIG. 32 is a flowchart illustrating a procedure in which a transmitting STA accesses a non-primary channel and receives a PPDU according to the present embodiment. An example of FIG. 32 can be performed in a network environment that supports a next-generation wireless LAN system (UHR (Ultra High Reliability) wireless LAN system or next wi-fi). The next-generation wireless LAN system is a wireless LAN system that improves on the 802.11be system and can satisfy backward compatibility with the 802.11be system. An example of FIG. 32 is performed at a transmitting STA, which may correspond to an access point (AP). The receiving STA of FIG. 32 may correspond to at least one STA (station). This embodiment proposes a method for transmitting and receiving PPDUs by performing backoff on a non-primary channel and performing channel access on another non-primary channel based on this backoff. In particular, this embodiment proposes limited rules for determining the location of a non-primary channel within an AP's BSS operating channel. In step S3210, the transmitting STA (station) performs a backoff on the first non-primary channel. In step S3220, the transmitting STA performs channel access for the second non-primary channel if the backoff value for the first non-primary channel is 0. In step S3230, the transmitting STA receives a PPDU from the receiving STA through an IDLE channel among the first and second non-primary channels. The above first non-primary channel is a secondary 20MHz channel that can perform the above backoff while the NAV (Network Allocation Vector) is set in the primary 20MHz channel. The above second non-primary channel is a secondary channel excluding the first non-primary channel in the BSS (Basic Service Set) operating channel. The above first non-primary channel is located in a secondary channel having half the size of the BSS operating channel. That is, the present embodiment proposes a method for performing channel access for a non-primary channel (or secondary channel) in a situation where a NAV (Basic NAV here) is set for the primary 20MHz channel. In particular, the present embodiment has the effect of maximizing channel utilization in terms of the bandwidth and puncturing pattern of a PPDU by proposing limited rules for determining the position of the non-primary channel within the BSS operating channel of the AP. In addition, by determining the non-primary channel by considering the overlapping of OBSS traffic and the non-primary channel through the present embodiment, it is possible to have an advantage in terms of the probability of performing channel access for the non-primary channel, and it is also possible to have the effect of improving the efficiency of wideband utilization. Specific examples of the bandwidth of a PPDU that can be generated and the puncturing pattern that can be utilized are as follows, since the first non-primary channel is located in a secondary channel having a size half that of the BSS operating channel. When the size of the above BSS operating channel is 160 MHz, the second non-primary channel may include a Non-Primary Channel Access (NPCA) 20 MHz channel, an NPCA 40 MHz channel, and an NPCA 80 MHz channel. The non-primary channel and the NPCA channel may also be denoted as a Secondary Channel Access (SCA) channel. The NPCA 20MHz channel may be a channel constituting a 40MHz channel capable of transmitting the PPDU together with the first non-primary channel. The NPCA 40MHz channel may be a channel constituting an 80MHz channel capable of transmitting the PPDU together with the 40MHz channel. The NPCA 80MHz channel may be a channel constituting a 160MHz channel capable of transmitting the PPDU together with the 80MHz channel. The 40MHz channel may be denoted as an SCA P40 (primary 40MHz) channel. The 80MHz channel may be denoted as an SCA P80 channel. The 160MHz channel may be denoted as an SCA P160 channel. The 320MHz channel described below may be denoted as an SCA P320 channel. The above first non-primary channel may be located in the 80MHz channel. That is, when the above first non-primary channel is located in a secondary channel (80MHz) having a size half that of the BSS operating channel (160MHz), the bandwidth and puncturing pattern of the optimized PPDU can be implemented as follows, thereby improving channel utilization. When only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. When the first non-primary channel and the NPCA 20MHz channel are idle, the PPDU can be transmitted through the 40MHz channel. When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are IDLE, the PPDU can be transmitted through the 80MHz channel. At this time, when the primary 20MHz channel is located in the NPCA 80MHz channel, the 80MHz channel may not be punctured. When the primary 20MHz channel is located in the 80MHz channel, the 20MHz channel in which the primary 20MHz channel is located among the 80MHz channels may be punctured. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are idle, the PPDU may be transmitted through the 160MHz channel. At this time, the 20MHz channel or the 40MHz channel in which the primary 20MHz channel is located among the 160MHz channels may be punctured. Additionally, when the size of the BSS operating channel is 320 MHz, the second non-primary channel may include an NPCA 20 MHz channel, an NPCA 40 MHz channel, an NPCA 80 MHz channel, and an NPCA 160 MHz channel. The NPCA 20MHz channel may be a channel constituting a 40MHz channel capable of transmitting the PPDU together with the first non-primary channel. The NPCA 40MHz channel may be a channel constituting an 80MHz channel capable of transmitting the PPDU together with the 40MHz channel. The NPCA 80MHz channel may be a channel constituting a 160MHz channel capable of transmitting the PPDU together with the 80MHz channel. The NPCA 160MHz channel may be a channel constituting a 320MHz channel capable of transmitting the PPDU together with the 160MHz channel. The above first non-primary channel may be located in the 160MHz channel. That is, when the above first non-primary channel is located in a secondary channel (160MHz) having a size half that of the BSS operating channel (320MHz), the bandwidth and puncturing pattern of the optimized PPDU can be implemented as follows, thereby improving channel utilization. If only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. When the first non-primary channel and the NPCA 20MHz channel are IDLE, the PPDU can be transmitted through the 40MHz channel. When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are IDLE, the PPDU can be transmitted through the 80MHz channel. At this time, when the primary 20MHz channel is located in the NPCA 80MHz channel, the 80MHz channel may not be punctured. When the primary 20MHz channel is located in the 80MHz channel, the 20MHz channel in which the primary 20MHz channel is located among the 80MHz channels may be punctured. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, the PPDU can be transmitted through the 160MHz channel. At this time, when the primary 20MHz channel is located in the NPCA 160MHz channel, the 160MHz channel may not be punctured. When the primary 20MHz channel is located in the 160MHz channel, the 20MHz channel in which the primary 20MHz channel is located among the 160MHz channels may be punctured. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, the NPCA 80MHz channel, and the NPCA 160MHz channel are IDLE, the PPDU may be transmitted through the 320MHz channel. At this time, at least one of a first 40MHz channel, a second 40MHz channel, and a third 40MHz channel may be punctured in the 320MHz channel. The first 40MHz channel may be a 40MHz channel in which the primary 20MHz channel is located. The second 40MHz channel may be a 40MHz channel that is continuous with the first 40MHz channel. The third 40MHz channel may be a 40MHz channel remaining in the 320MHz channel, excluding the first and second 40MHz channels. Additionally, when the size of the BSS operating channel is 80 MHz, the second non-primary channel may include an NPCA 20 MHz channel and an NPCA 40 MHz channel. The above NPCA 20MHz channel may be a channel that constitutes a 40MHz channel capable of transmitting the PPDU together with the first non-primary channel. The above NPCA 40MHz channel may be a channel that constitutes an 80MHz channel capable of transmitting the PPDU together with the 40MHz channel. The above first non-primary channel may be located in the 40MHz channel. That is, when the above first non-primary channel is located in a secondary channel (40MHz) having a size half that of the BSS operating channel (80MHz), the bandwidth and puncturing pattern of the optimized PPDU can be implemented as follows, thereby improving channel utilization. When only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. When the first non-primary channel and the NPCA 20MHz channel are idle, the PPDU can be transmitted through the 40MHz channel. When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are idle, the PPDU can be transmitted through the 80MHz channel. At this time, the 20MHz channel in which the primary 20MHz channel is located among the 80MHz channels can be punctured. The configuration of the first and second non-primary channels is determined based on the size of the BSS operating channel and the location of the first non-primary channel. A channel configuration can be newly defined to access the above non-primary channel (or secondary channel), and rules can be defined regarding which channels are included in the non-primary channel (or secondary channel) to transmit and receive PPDUs having bandwidths of various sizes. That is, the present embodiment has the effect of defining a configuration of a channel to be used for non-primary channel access, and performing backoff based on the non-primary channel based on this, and performing CCA for other non-primary channels to transmit and receive PPDUs in a wider bandwidth. A specific embodiment for determining the configuration (or arrangement) of the first and second non-primary channels is as follows. If the size of the BSS operating channel is 160 MHz, the BSS operating channel may include first to eighth 20 MHz channels, and it may be assumed that the first to eighth 20 MHz channels are arranged in order of frequency from low to high. For example, the first non-primary channel may be located on a 20 MHz channel having the second lowest frequency among the BSS operating channels (the second 20 MHz channel). The primary 20 MHz channel may be located on a 20 MHz channel having the lowest frequency among the BSS operating channels (the first 20 MHz channel). At this time, if only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. That is, the PPDU can be transmitted using only the second 20 MHz channel. When the first non-primary channel and the NPCA 40MHz channel are IDLE, the PPDU is transmitted through the 80MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 80MHz channel is punctured. That is, the PPDU may be transmitted through the second to fourth 20MHz channels among the 80MHz channels, excluding the first 20MHz channel. When the first non-primary channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, the PPDU is transmitted through the 160MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 160MHz channel is punctured. That is, the PPDU may be transmitted through the second to eighth 20MHz channels among the 160MHz channels, excluding the first 20MHz channel. As another example, the first non-primary channel may be located on a 20 MHz channel having the third lowest frequency among the BSS operating channels (the third 20 MHz channel). The primary 20 MHz channel may be located on a 20 MHz channel having the lowest frequency among the BSS operating channels (the first 20 MHz channel). At this time, if only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. That is, the PPDU can be transmitted using only the third 20 MHz channel. When the first non-primary channel and the NPCA 20MHz channel are idle, the PPDU can be transmitted through the 40MHz channel. That is, the PPDU can be transmitted using the third and fourth 20MHz channels. When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are IDLE, the PPDU is transmitted through the 80MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 80MHz channel is punctured. That is, the PPDU may be transmitted through the second to fourth 20MHz channels among the 80MHz channels, excluding the first 20MHz channel. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, the PPDU is transmitted through the 160MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 160MHz channel is punctured. That is, the PPDU may be transmitted through the second to eighth 20MHz channels among the 160MHz channels, excluding the first 20MHz channel. As another example, the first non-primary channel may be located on a 20 MHz channel having the fifth lowest frequency among the BSS operating channels (the fifth 20 MHz channel). The primary 20 MHz channel may be located on a 20 MHz channel having the lowest frequency among the BSS operating channels (the first 20 MHz channel). When only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. That is, the PPDU can be transmitted using only the fifth 20 MHz channel. When the first non-primary channel and the NPCA 20MHz channel are idle, the PPDU can be transmitted through the 40MHz channel. That is, the PPDU can be transmitted using the fifth and sixth 20MHz channels. When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are idle, the PPDU can be transmitted through the 80MHz channel. That is, the PPDU can be transmitted using the fifth to eighth 20MHz channels. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, the PPDU is transmitted through the 160MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 160MHz channel is punctured. That is, the PPDU may be transmitted through the second to eighth 20MHz channels among the 160MHz channels, excluding the first 20MHz channel. In addition, when the size of the BSS operating channel is 320 MHz, the BSS operating channel may include the first to sixteenth 20 MHz channels, and it may be assumed that the first to sixteenth 20 MHz channels are arranged in order of frequency from low to high. For example, the first non-primary channel may be located on a 20 MHz channel having the second lowest frequency among the BSS operating channels (the second 20 MHz channel). The primary 20 MHz channel may be located on a 20 MHz channel having the lowest frequency among the BSS operating channels (the first 20 MHz channel). At this time, if only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. That is, the PPDU can be transmitted using only the second 20 MHz channel. When the first non-primary channel and the NPCA 40MHz channel are IDLE, the PPDU is transmitted through the 80MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 80MHz channel is punctured. That is, the PPDU may be transmitted through the second to fourth 20MHz channels among the 80MHz channels, excluding the first 20MHz channel. When the first non-primary channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, the PPDU is transmitted through the 160MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 160MHz channel is punctured. That is, the PPDU may be transmitted through the second to eighth 20MHz channels among the 160MHz channels, excluding the first 20MHz channel. When the first non-primary channel, the NPCA 40MHz channel, the NPCA 80MHz channel, and the NPCA 160MHz channel are IDLE, the PPDU is transmitted through the 320MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 320MHz channel is punctured. That is, the PPDU may be transmitted through the second to sixteenth 20MHz channels among the 320MHz channels, excluding the first 20MHz channel. As another example, the first non-primary channel may be located on a 20 MHz channel having the third lowest frequency among the BSS operating channels (the third 20 MHz channel). The primary 20 MHz channel may be located on a 20 MHz channel having the lowest frequency among the BSS operating channels (the first 20 MHz channel). When only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. That is, the PPDU can be transmitted using only the third 20 MHz channel. When the first non-primary channel and the NPCA 20MHz channel are idle, the PPDU can be transmitted through the 40MHz channel. That is, the PPDU can be transmitted using the third and fourth 20MHz channels. When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are IDLE, the PPDU is transmitted through the 80MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 80MHz channel is punctured. That is, the PPDU may be transmitted through the second to fourth 20MHz channels among the 80MHz channels, excluding the first 20MHz channel. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, the PPDU is transmitted through the 160MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 160MHz channel is punctured. That is, the PPDU may be transmitted through the second to eighth 20MHz channels among the 160MHz channels, excluding the first 20MHz channel. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, the NPCA 80MHz channel, and the NPCA 160MHz channel are IDLE, the PPDU is transmitted through the 320MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 320MHz channel is punctured. That is, the PPDU may be transmitted through the second to sixteenth 20MHz channels among the 320MHz channels, excluding the first 20MHz channel. As another example, the first non-primary channel may be located on a 20 MHz channel having the ninth lowest frequency among the BSS operating channels (the ninth 20 MHz channel). The primary 20 MHz channel may be located on a 20 MHz channel having the lowest frequency among the BSS operating channels (the first 20 MHz channel). When only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. That is, the PPDU can be transmitted using only the 9th 20 MHz channel. When the first non-primary channel and the NPCA 20MHz channel are idle, the PPDU can be transmitted through the 40MHz channel. That is, the PPDU can be transmitted using the ninth and tenth 20MHz channels. When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are idle, the PPDU can be transmitted through the 80MHz channel. That is, the PPDU can be transmitted using the ninth to twelfth 20MHz channels. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, the PPDU can be transmitted through the 160MHz channel. That is, the PPDU can be transmitted using the 9th to 16th 20MHz channels. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, the NPCA 80MHz channel, and the NPCA 160MHz channel are IDLE, the PPDU is transmitted through the 320MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 320MHz channel is punctured. That is, the PPDU may be transmitted through the second to sixteenth 20MHz channels among the 320MHz channels, excluding the first 20MHz channel. According to the above-described embodiment, since the first and second non-primary channels are arranged in various ways, the method proposed by this embodiment has the effect that the channels for transmitting and receiving the PPDU can be varied, and channel utilization for a wide bandwidth can be adjusted. FIG. 33 is a flowchart illustrating a procedure in which a receiving STA accesses a non-primary channel and transmits a PPDU according to the present embodiment. An example of FIG. 33 can be performed in a network environment that supports a next-generation wireless LAN system (UHR (Ultra High Reliability) wireless LAN system or next wi-fi). The next-generation wireless LAN system is a wireless LAN system that improves on the 802.11be system and can satisfy backward compatibility with the 802.11be system. An example of FIG. 33 is performed at a receiving STA, which may correspond to at least one STA (station). The transmitting STA of FIG. 33 may correspond to an AP (access point). This embodiment proposes a method for transmitting and receiving PPDUs by performing backoff on a non-primary channel and performing channel access on another non-primary channel based on this backoff. In particular, this embodiment proposes limited rules for determining the location of a non-primary channel within an AP's BSS operating channel. In step S3310, the receiving STA (station) performs a backoff on the first non-primary channel. In step S3320, the receiving STA performs channel access for the second non-primary channel if the backoff value for the first non-primary channel is 0. In step S3330, the receiving STA transmits a PPDU to the transmitting STA through an IDLE channel among the first and second non-primary channels. The above first non-primary channel is a secondary 20MHz channel that can perform the above backoff while the NAV (Network Allocation Vector) is set in the primary 20MHz channel. The above second non-primary channel is a secondary channel excluding the first non-primary channel in the BSS (Basic Service Set) operating channel. The above first non-primary channel is located in a secondary channel having half the size of the BSS operating channel. That is, the present embodiment proposes a method for performing channel access for a non-primary channel (or secondary channel) in a situation where a NAV (Basic NAV here) is set for the primary 20MHz channel. In particular, the present embodiment has the effect of maximizing channel utilization in terms of the bandwidth and puncturing pattern of a PPDU by proposing limited rules for determining the position of the non-primary channel within the BSS operating channel of the AP. In addition, by determining the non-primary channel by considering the overlapping of OBSS traffic and the non-primary channel through the present embodiment, it is possible to have an advantage in terms of the probability of performing channel access for the non-primary channel, and it is also possible to have the effect of improving the efficiency of wideband utilization. Specific examples of the bandwidth of a PPDU that can be generated and the puncturing pattern that can be utilized are as follows, since the first non-primary channel is located in a secondary channel having a size half that of the BSS operating channel. When the size of the above BSS operating channel is 160 MHz, the second non-primary channel may include a Non-Primary Channel Access (NPCA) 20 MHz channel, an NPCA 40 MHz channel, and an NPCA 80 MHz channel. The non-primary channel and the NPCA channel may also be denoted as a Secondary Channel Access (SCA) channel. The NPCA 20MHz channel may be a channel constituting a 40MHz channel capable of transmitting the PPDU together with the first non-primary channel. The NPCA 40MHz channel may be a channel constituting an 80MHz channel capable of transmitting the PPDU together with the 40MHz channel. The NPCA 80MHz channel may be a channel constituting a 160MHz channel capable of transmitting the PPDU together with the 80MHz channel. The 40MHz channel may be denoted as an SCA P40 (primary 40MHz) channel. The 80MHz channel may be denoted as an SCA P80 channel. The 160MHz channel may be denoted as an SCA P160 channel. The 320MHz channel described below may be denoted as an SCA P320 channel. The above first non-primary channel may be located in the 80MHz channel. That is, when the above first non-primary channel is located in a secondary channel (80MHz) having a size half that of the BSS operating channel (160MHz), the bandwidth and puncturing pattern of the optimized PPDU can be implemented as follows, thereby improving channel utilization. When only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. When the first non-primary channel and the NPCA 20MHz channel are idle, the PPDU can be transmitted through the 40MHz channel. When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are IDLE, the PPDU can be transmitted through the 80MHz channel. At this time, when the primary 20MHz channel is located in the NPCA 80MHz channel, the 80MHz channel may not be punctured. When the primary 20MHz channel is located in the 80MHz channel, the 20MHz channel in which the primary 20MHz channel is located among the 80MHz channels may be punctured. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are idle, the PPDU may be transmitted through the 160MHz channel. At this time, the 20MHz channel or the 40MHz channel in which the primary 20MHz channel is located among the 160MHz channels may be punctured. Additionally, when the size of the BSS operating channel is 320 MHz, the second non-primary channel may include an NPCA 20 MHz channel, an NPCA 40 MHz channel, an NPCA 80 MHz channel, and an NPCA 160 MHz channel. The NPCA 20MHz channel may be a channel constituting a 40MHz channel capable of transmitting the PPDU together with the first non-primary channel. The NPCA 40MHz channel may be a channel constituting an 80MHz channel capable of transmitting the PPDU together with the 40MHz channel. The NPCA 80MHz channel may be a channel constituting a 160MHz channel capable of transmitting the PPDU together with the 80MHz channel. The NPCA 160MHz channel may be a channel constituting a 320MHz channel capable of transmitting the PPDU together with the 160MHz channel. The above first non-primary channel may be located in the 160MHz channel. That is, when the above first non-primary channel is located in a secondary channel (160MHz) having a size half that of the BSS operating channel (320MHz), the bandwidth and puncturing pattern of the optimized PPDU can be implemented as follows, thereby improving channel utilization. If only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. When the first non-primary channel and the NPCA 20MHz channel are IDLE, the PPDU can be transmitted through the 40MHz channel. When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are IDLE, the PPDU can be transmitted through the 80MHz channel. At this time, when the primary 20MHz channel is located in the NPCA 80MHz channel, the 80MHz channel may not be punctured. When the primary 20MHz channel is located in the 80MHz channel, the 20MHz channel in which the primary 20MHz channel is located among the 80MHz channels may be punctured. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, the PPDU can be transmitted through the 160MHz channel. At this time, when the primary 20MHz channel is located in the NPCA 160MHz channel, the 160MHz channel may not be punctured. When the primary 20MHz channel is located in the 160MHz channel, the 20MHz channel in which the primary 20MHz channel is located among the 160MHz channels may be punctured. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, the NPCA 80MHz channel, and the NPCA 160MHz channel are IDLE, the PPDU may be transmitted through the 320MHz channel. At this time, at least one of a first 40MHz channel, a second 40MHz channel, and a third 40MHz channel may be punctured in the 320MHz channel. The first 40MHz channel may be a 40MHz channel in which the primary 20MHz channel is located. The second 40MHz channel may be a 40MHz channel that is continuous with the first 40MHz channel. The third 40MHz channel may be a 40MHz channel remaining in the 320MHz channel, excluding the first and second 40MHz channels. Additionally, when the size of the BSS operating channel is 80 MHz, the second non-primary channel may include an NPCA 20 MHz channel and an NPCA 40 MHz channel. The above NPCA 20MHz channel may be a channel that constitutes a 40MHz channel capable of transmitting the PPDU together with the first non-primary channel. The above NPCA 40MHz channel may be a channel that constitutes an 80MHz channel capable of transmitting the PPDU together with the 40MHz channel. The above first non-primary channel may be located in the 40MHz channel. That is, when the above first non-primary channel is located in a secondary channel (40MHz) having a size half that of the BSS operating channel (80MHz), the bandwidth and puncturing pattern of the optimized PPDU can be implemented as follows, thereby improving channel utilization. When only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. When the first non-primary channel and the NPCA 20MHz channel are idle, the PPDU can be transmitted through the 40MHz channel. When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are idle, the PPDU can be transmitted through the 80MHz channel. At this time, the 20MHz channel in which the primary 20MHz channel is located among the 80MHz channels can be punctured. The configuration of the first and second non-primary channels is determined based on the size of the BSS operating channel and the location of the first non-primary channel. A channel configuration can be newly defined to access the above non-primary channel (or secondary channel), and rules can be defined regarding which channels are included in the non-primary channel (or secondary channel) to transmit and receive PPDUs having bandwidths of various sizes. That is, the present embodiment has the effect of defining a configuration of a channel to be used for non-primary channel access, and performing backoff based on the non-primary channel based on this, and performing CCA for other non-primary channels to transmit and receive PPDUs in a wider bandwidth. A specific embodiment for determining the configuration (or arrangement) of the first and second non-primary channels is as follows. If the size of the BSS operating channel is 160 MHz, the BSS operating channel may include first to eighth 20 MHz channels, and it may be assumed that the first to eighth 20 MHz channels are arranged in order of frequency from low to high. For example, the first non-primary channel may be located on a 20 MHz channel having the second lowest frequency among the BSS operating channels (the second 20 MHz channel). The primary 20 MHz channel may be located on a 20 MHz channel having the lowest frequency among the BSS operating channels (the first 20 MHz channel). At this time, if only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. That is, the PPDU can be transmitted using only the second 20 MHz channel. When the first non-primary channel and the NPCA 40MHz channel are IDLE, the PPDU is transmitted through the 80MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 80MHz channel is punctured. That is, the PPDU may be transmitted through the second to fourth 20MHz channels among the 80MHz channels, excluding the first 20MHz channel. When the first non-primary channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, the PPDU is transmitted through the 160MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 160MHz channel is punctured. That is, the PPDU may be transmitted through the second to eighth 20MHz channels among the 160MHz channels, excluding the first 20MHz channel. As another example, the first non-primary channel may be located on a 20 MHz channel having the third lowest frequency among the BSS operating channels (the third 20 MHz channel). The primary 20 MHz channel may be located on a 20 MHz channel having the lowest frequency among the BSS operating channels (the first 20 MHz channel). At this time, if only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. That is, the PPDU can be transmitted using only the third 20 MHz channel. When the first non-primary channel and the NPCA 20MHz channel are idle, the PPDU can be transmitted through the 40MHz channel. That is, the PPDU can be transmitted using the third and fourth 20MHz channels. When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are IDLE, the PPDU is transmitted through the 80MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 80MHz channel is punctured. That is, the PPDU may be transmitted through the second to fourth 20MHz channels among the 80MHz channels, excluding the first 20MHz channel. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, the PPDU is transmitted through the 160MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 160MHz channel is punctured. That is, the PPDU may be transmitted through the second to eighth 20MHz channels among the 160MHz channels, excluding the first 20MHz channel. As another example, the first non-primary channel may be located on a 20 MHz channel having the fifth lowest frequency among the BSS operating channels (the fifth 20 MHz channel). The primary 20 MHz channel may be located on a 20 MHz channel having the lowest frequency among the BSS operating channels (the first 20 MHz channel). When only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. That is, the PPDU can be transmitted using only the fifth 20 MHz channel. When the first non-primary channel and the NPCA 20MHz channel are idle, the PPDU can be transmitted through the 40MHz channel. That is, the PPDU can be transmitted using the fifth and sixth 20MHz channels. When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are idle, the PPDU can be transmitted through the 80MHz channel. That is, the PPDU can be transmitted using the fifth to eighth 20MHz channels. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, the PPDU is transmitted through the 160MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 160MHz channel is punctured. That is, the PPDU may be transmitted through the second to eighth 20MHz channels among the 160MHz channels, excluding the first 20MHz channel. In addition, when the size of the BSS operating channel is 320 MHz, the BSS operating channel may include the first to sixteenth 20 MHz channels, and it may be assumed that the first to sixteenth 20 MHz channels are arranged in order of frequency from low to high. For example, the first non-primary channel may be located on a 20 MHz channel having the second lowest frequency among the BSS operating channels (the second 20 MHz channel). The primary 20 MHz channel may be located on a 20 MHz channel having the lowest frequency among the BSS operating channels (the first 20 MHz channel). At this time, if only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. That is, the PPDU can be transmitted using only the second 20 MHz channel. When the first non-primary channel and the NPCA 40MHz channel are IDLE, the PPDU is transmitted through the 80MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 80MHz channel is punctured. That is, the PPDU may be transmitted through the second to fourth 20MHz channels among the 80MHz channels, excluding the first 20MHz channel. When the first non-primary channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, the PPDU is transmitted through the 160MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 160MHz channel is punctured. That is, the PPDU may be transmitted through the second to eighth 20MHz channels among the 160MHz channels, excluding the first 20MHz channel. When the first non-primary channel, the NPCA 40MHz channel, the NPCA 80MHz channel, and the NPCA 160MHz channel are IDLE, the PPDU is transmitted through the 320MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 320MHz channel is punctured. That is, the PPDU may be transmitted through the second to sixteenth 20MHz channels among the 320MHz channels, excluding the first 20MHz channel. As another example, the first non-primary channel may be located on a 20 MHz channel having the third lowest frequency among the BSS operating channels (the third 20 MHz channel). The primary 20 MHz channel may be located on a 20 MHz channel having the lowest frequency among the BSS operating channels (the first 20 MHz channel). When only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. That is, the PPDU can be transmitted using only the third 20 MHz channel. When the first non-primary channel and the NPCA 20MHz channel are idle, the PPDU can be transmitted through the 40MHz channel. That is, the PPDU can be transmitted using the third and fourth 20MHz channels. When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are IDLE, the PPDU is transmitted through the 80MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 80MHz channel is punctured. That is, the PPDU may be transmitted through the second to fourth 20MHz channels among the 80MHz channels, excluding the first 20MHz channel. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, the PPDU is transmitted through the 160MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 160MHz channel is punctured. That is, the PPDU may be transmitted through the second to eighth 20MHz channels among the 160MHz channels, excluding the first 20MHz channel. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, the NPCA 80MHz channel, and the NPCA 160MHz channel are IDLE, the PPDU is transmitted through the 320MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 320MHz channel is punctured. That is, the PPDU may be transmitted through the second to sixteenth 20MHz channels among the 320MHz channels, excluding the first 20MHz channel. As another example, the first non-primary channel may be located on a 20 MHz channel having the ninth lowest frequency among the BSS operating channels (the ninth 20 MHz channel). The primary 20 MHz channel may be located on a 20 MHz channel having the lowest frequency among the BSS operating channels (the first 20 MHz channel). When only the first non-primary channel is idle, the PPDU can be transmitted through the first non-primary channel. That is, the PPDU can be transmitted using only the 9th 20 MHz channel. When the first non-primary channel and the NPCA 20MHz channel are idle, the PPDU can be transmitted through the 40MHz channel. That is, the PPDU can be transmitted using the ninth and tenth 20MHz channels. When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are idle, the PPDU can be transmitted through the 80MHz channel. That is, the PPDU can be transmitted using the ninth to twelfth 20MHz channels. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, the PPDU can be transmitted through the 160MHz channel. That is, the PPDU can be transmitted using the 9th to 16th 20MHz channels. When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, the NPCA 80MHz channel, and the NPCA 160MHz channel are IDLE, the PPDU is transmitted through the 320MHz channel, and the PPDU may include information that the primary 20MHz channel included in the 320MHz channel is punctured. That is, the PPDU may be transmitted through the second to sixteenth 20MHz channels among the 320MHz channels, excluding the first 20MHz channel. According to the above-described embodiment, since the first and second non-primary channels are arranged in various ways, the method proposed by this embodiment has the effect that the channels for transmitting and receiving the PPDU can be varied, and channel utilization for a wide bandwidth can be adjusted. <Device Configuration> The technical features of the present specification described above can be applied to various devices and methods. For example, the technical features of the present specification described above can be performed / supported by the devices of FIG. 1 and / or FIG. 14. For example, the technical features of the present specification described above can be applied only to a part of FIG. 1 and / or FIG. 14. For example, the technical features of the present specification described above can be implemented based on the processing chip (114, 124) of FIG. 1, or based on the processor (111, 121) and the memory (112, 122) of FIG. 1, or based on the processor (610) and the memory (620) of FIG. 14. For example, the device of the present specification performs a backoff for a first non-primary channel; and when the backoff value for the first non-primary channel is 0, performs channel access for a second non-primary channel; And transmits a PPDU to a transmitting STA (station) through an IDLE channel among the first and second non-primary channels. The technical features of this specification can be implemented based on a computer-readable medium (CRM). For example, the CRM proposed by this specification is at least one computer-readable recording medium containing instructions that are executed by at least one processor. The CRM may store instructions for performing operations including: performing a backoff for a first non-primary channel from a transmitting STA (station); performing channel access for a second non-primary channel when the backoff value for the first non-primary channel is 0; and transmitting a PPDU to the transmitting STA (station) through an IDLE channel among the first and second non-primary channels. The instructions stored in the CRM of the present specification may be executed by at least one processor. At least one processor related to the CRM of the present specification may be the processor (111, 121) or the processing chip (114, 124) of FIG. 1, or the processor (610) of FIG. 14. Meanwhile, the CRM of this specification may be the memory (112, 122) of FIG. 1, the memory (620) of FIG. 14, or a separate external memory / storage medium / disk, etc. 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). 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. 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. 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. 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. 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. Machine learning can be classified into supervised learning, unsupervised learning, and reinforcement learning depending on the learning method. 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. 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. Additionally, the above-described technical features can be applied to wireless communication of robots. 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. 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. Additionally, the above-described technical features can be applied to devices that support extended reality. 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. 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. 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. The claims set forth in this specification may be combined in various ways. For example, the technical features of the method claims of this specification may be combined and implemented as a device, and the technical features of the device claims of this specification may be combined and implemented as a method. Furthermore, the technical features of the method claims and the technical features of the device claims of this specification may be combined and implemented as a device, and the technical features of the method claims and the technical features of the device claims of this specification may be combined and implemented as a method.

Claims

1. In a wireless LAN system, A step in which a receiving STA (station) performs a backoff for a first non-primary channel; The receiving STA performs channel access for a second non-primary channel when the backoff value for the first non-primary channel is 0; and The receiving STA comprises a step of transmitting a PPDU to a transmitting STA through an IDLE channel among the first and second non-primary channels, The above first non-primary channel is a secondary 20MHz channel that can perform the backoff while the NAV (Network Allocation Vector) is set to the primary 20MHz channel. The above second non-primary channel is a secondary channel excluding the first non-primary channel in the BSS (Basic Service Set) operating channel, and The above first non-primary channel is located in a secondary channel having half the size of the BSS operating channel. method.

2. In paragraph 1, If the size of the above BSS operating channel is 160MHz, The above second non-primary channel includes a Non-Primary Channel Access (NPCA) 20MHz channel, an NPCA 40MHz channel, and an NPCA 80MHz channel, The above NPCA 20MHz channel is a channel that constitutes a 40MHz channel capable of transmitting the PPDU together with the first non-primary channel. The above NPCA 40MHz channel is a channel that constitutes an 80MHz channel that can transmit the PPDU together with the above 40MHz channel, The above NPCA 80MHz channel is a channel that constitutes a 160MHz channel that can transmit the PPDU together with the above 80MHz channel. method.

3. In paragraph 2, The above first non-primary channel is located in the 80MHz channel, When only the first non-primary channel is idle, the PPDU is transmitted through the first non-primary channel, When the first non-primary channel and the NPCA 20MHz channel are IDLE, the PPDU is transmitted through the 40MHz channel, When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are IDLE, the PPDU is transmitted through the 80MHz channel, When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel and the NPCA 80MHz channel are IDLE, the PPDU is transmitted through the 160MHz channel. method.

4. In paragraph 3, When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are IDLE, If the primary 20MHz channel is located in the NPCA 80MHz channel, the 80MHz channel is not punctured, If the primary 20MHz channel is located in the 80MHz channel, the 20MHz channel in which the primary 20MHz channel is located among the 80MHz channels is punctured. method.

5. In paragraph 3, When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, Among the above 160MHz channels, the 20MHz channel or 40MHz channel where the primary 20MHz channel is located is punctured. method.

6. In paragraph 1, If the size of the above BSS operating channel is 320MHz, The above second non-primary channel includes an NPCA 20MHz channel, an NPCA 40MHz channel, an NPCA 80MHz channel, and an NPCA 160MHz channel, The above NPCA 20MHz channel is a channel that constitutes a 40MHz channel capable of transmitting the PPDU together with the first non-primary channel. The above NPCA 40MHz channel is a channel that constitutes an 80MHz channel that can transmit the PPDU together with the above 40MHz channel, The above NPCA 80MHz channel is a channel that constitutes a 160MHz channel that can transmit the PPDU together with the above 80MHz channel. The above NPCA 160MHz channel is a channel that constitutes a 320MHz channel that can transmit the PPDU together with the above 160MHz channel. method.

7. In paragraph 6, The above first non-primary channel is located in the 160MHz channel, When only the first non-primary channel is idle, the PPDU is transmitted through the first non-primary channel, When the first non-primary channel and the NPCA 20MHz channel are IDLE, the PPDU is transmitted through the 40MHz channel, When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are IDLE, the PPDU is transmitted through the 80MHz channel, When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, the PPDU is transmitted through the 160MHz channel, When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, the NPCA 80MHz channel and the NPCA 160MHz channel are IDLE, the PPDU is transmitted through the 320MHz channel. method.

8. In paragraph 7, When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are IDLE, If the primary 20MHz channel is located in the NPCA 80MHz channel, the 80MHz channel is not punctured, If the primary 20MHz channel is located in the 80MHz channel, the 20MHz channel in which the primary 20MHz channel is located among the 80MHz channels is punctured. method.

9. In paragraph 7, When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, If the primary 20MHz channel is located in the NPCA 160MHz channel, the 160MHz channel is not punctured, If the primary 20MHz channel is located in the 160MHz channel, the 20MHz channel in which the primary 20MHz channel is located among the 160MHz channels is punctured. method.

10. In paragraph 7, When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, the NPCA 80MHz channel, and the NPCA 160MHz channel are IDLE, In the above 320MHz channel, at least one of the first 40MHz channel, the second 40MHz channel and the third 40MHz channel is punctured, The above first 40MHz channel is a 40MHz channel where the primary 20MHz channel is located, The second 40MHz channel is a 40MHz channel that is continuous with the first 40MHz channel, The third 40MHz channel is the remaining 40MHz channel excluding the first and second 40MHz channels in the 320MHz channel. method.

11. In a wireless LAN system, a receiving STA (station) memory; transceiver; and A processor operatively coupled to the memory and the transceiver, the processor comprising: Perform backoff on the first non-primary channel; If the backoff value for the first non-primary channel is 0, channel access is performed for the second non-primary channel; and Transmitting a PPDU to a transmitting STA through an IDLE channel among the first and second non-primary channels, The above first non-primary channel is a secondary 20MHz channel that can perform the backoff while the NAV (Network Allocation Vector) is set to the primary 20MHz channel. The above second non-primary channel is a secondary channel excluding the first non-primary channel in the BSS (Basic Service Set) operating channel, and The above first non-primary channel is located in a secondary channel having half the size of the BSS operating channel. Receiving STA.

12. In a wireless LAN system, A step in which a transmitting STA (station) performs a backoff for a first non-primary channel; The transmitting STA performs channel access for a second non-primary channel when the backoff value for the first non-primary channel is 0; and The transmitting STA comprises a step of receiving a PPDU from a receiving STA through an IDLE channel among the first and second non-primary channels, The above first non-primary channel is a secondary 20MHz channel that can perform the backoff while the NAV (Network Allocation Vector) is set to the primary 20MHz channel. The above second non-primary channel is a secondary channel excluding the first non-primary channel in the BSS (Basic Service Set) operating channel, and The above first non-primary channel is located in a secondary channel having half the size of the BSS operating channel. method.

13. In paragraph 12, If the size of the above BSS operating channel is 160MHz, The above second non-primary channel includes a Non-Primary Channel Access (NPCA) 20MHz channel, an NPCA 40MHz channel, and an NPCA 80MHz channel, The above NPCA 20MHz channel is a channel that constitutes a 40MHz channel capable of transmitting the PPDU together with the first non-primary channel. The above NPCA 40MHz channel is a channel that constitutes an 80MHz channel that can transmit the PPDU together with the above 40MHz channel, The above NPCA 80MHz channel is a channel that constitutes a 160MHz channel that can transmit the PPDU together with the above 80MHz channel. method.

14. In paragraph 13, The above first non-primary channel is located in the 80MHz channel, When only the first non-primary channel is idle, the PPDU is transmitted through the first non-primary channel, When the first non-primary channel and the NPCA 20MHz channel are IDLE, the PPDU is transmitted through the 40MHz channel, When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are IDLE, the PPDU is transmitted through the 80MHz channel, When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel and the NPCA 80MHz channel are IDLE, the PPDU is transmitted through the 160MHz channel. method.

15. In paragraph 14, When the first non-primary channel, the NPCA 20MHz channel, and the NPCA 40MHz channel are IDLE, If the primary 20MHz channel is located in the NPCA 80MHz channel, the 80MHz channel is not punctured, If the primary 20MHz channel is located in the 80MHz channel, the 20MHz channel in which the primary 20MHz channel is located among the 80MHz channels is punctured. method.

16. In paragraph 14, When the first non-primary channel, the NPCA 20MHz channel, the NPCA 40MHz channel, and the NPCA 80MHz channel are IDLE, Among the above 160MHz channels, the 20MHz channel or 40MHz channel where the primary 20MHz channel is located is punctured. method.

17. In paragraph 12, If the size of the above BSS operating channel is 320MHz, The above second non-primary channel includes an NPCA 20MHz channel, an NPCA 40MHz channel, an NPCA 80MHz channel, and an NPCA 160MHz channel, The above NPCA 20MHz channel is a channel that constitutes a 40MHz channel capable of transmitting the PPDU together with the first non-primary channel. The above NPCA 40MHz channel is a channel that constitutes an 80MHz channel that can transmit the PPDU together with the above 40MHz channel, The above NPCA 80MHz channel is a channel that constitutes a 160MHz channel that can transmit the PPDU together with the above 80MHz channel. The above NPCA 160MHz channel is a channel that constitutes a 320MHz channel that can transmit the PPDU together with the above 160MHz channel. method.

18. In a wireless LAN system, a transmitting STA (station) memory; transceiver; and A processor operatively coupled to the memory and the transceiver, the processor comprising: Perform backoff on the first non-primary channel; If the backoff value for the first non-primary channel is 0, channel access is performed for the second non-primary channel; and Receive a PPDU from a receiving STA through an IDLE channel among the first and second non-primary channels, The above first non-primary channel is a secondary 20MHz channel that can perform the backoff while the NAV (Network Allocation Vector) is set to the primary 20MHz channel. The above second non-primary channel is a secondary channel excluding the first non-primary channel in the BSS (Basic Service Set) operating channel, and The above first non-primary channel is located in a secondary channel having half the size of the BSS operating channel. Transmitting STA.

19. At least one computer-readable medium containing instructions based on being executed by at least one processor, A step of performing backoff for the first non-primary channel; When the backoff value for the first non-primary channel is 0, performing channel access for the second non-primary channel; and Including a step of transmitting a PPDU to a transmitting STA (station) through an IDLE channel among the first and second non-primary channels, The above first non-primary channel is a secondary 20MHz channel that can perform the backoff while the NAV (Network Allocation Vector) is set to the primary 20MHz channel. The above second non-primary channel is a secondary channel excluding the first non-primary channel in the BSS (Basic Service Set) operating channel, and The above first non-primary channel is located in a secondary channel having half the size of the BSS operating channel. Recording medium.

20. In a wireless LAN system, in the device, memory; and A processor operatively coupled to the memory, the processor comprising: Perform backoff on the first non-primary channel; If the backoff value for the first non-primary channel is 0, channel access is performed for the second non-primary channel; and Transmitting a PPDU to a transmitting STA (station) through an IDLE channel among the first and second non-primary channels, The above first non-primary channel is a secondary 20MHz channel that can perform the backoff while the NAV (Network Allocation Vector) is set to the primary 20MHz channel. The above second non-primary channel is a secondary channel excluding the first non-primary channel in the BSS (Basic Service Set) operating channel, and The above first non-primary channel is located in a secondary channel having half the size of the BSS operating channel. device.

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