Method and apparatus for transmitting or receiving channel information on operating band in wireless LAN system

Abstract

Disclosed are a method and an apparatus for transmitting or receiving channel information on an operating band in a wireless LAN system. According to an embodiment of the present disclosure, a method performed by a first station (STA) in a wireless LAN system may comprise the steps of: transmitting a first frame to a second STA on a second frequency band, the first frame includes one or more pieces of information of first information about a specific channel in a first frequency band or second information about channel allocation in the first frequency band; and transmitting a second frame to the second STA or receiving the second frame from the second STA on the first frequency band on the basis of one or more pieces of information among the first information or the second information.

Description

Technical Field

[0001] The present disclosure relates to a method and apparatus for transmitting or receiving channel information about an operating frequency band in a wireless local area network (WLAN) system. Background Art

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

[0003] To provide a more advanced wireless communication environment, improved technologies for Extremely High Throughput (EHT) are being discussed. For example, technologies for MIMO and multi-access point (AP) coordination that support increased bandwidth, efficient utilization of multiple frequency bands, and increased spatial streams are being studied. Specifically, various technologies are being studied to support low-latency or real-time services. Furthermore, new technologies are being discussed to support Ultra-High Reliability (UHR), including improvements or extensions to EHT technologies. Summary of the Invention

[0004] Technical issues

[0005] A technical problem of the present disclosure is to provide a method and apparatus for transmitting or receiving channel information about an operating frequency band in a WLAN system.

[0006] An additional technical problem of the present disclosure is to provide a method and apparatus for transmitting or receiving channel information for frame exchange in another operating frequency band in a specific operating frequency band in a WLAN system.

[0007] The technical objectives to be achieved by the present disclosure are not limited to the above-mentioned technical objectives, and those skilled in the art can clearly understand other technical objectives not described herein through the following description.

[0008] Technical Solution

[0009] According to one aspect of the present disclosure, a method performed by a first station (STA) in a WLAN system may include: sending a first frame to a second STA on a second frequency band, the first frame including at least one of first information about a specific channel in the first frequency band or second information about channel allocation in the first frequency band; and performing transmission or reception of a second frame with the second STA on the first frequency band based on at least one of the first information or the second information.

[0010] According to additional aspects of the present disclosure, a method performed by a second station (STA) in a WLAN system may include: receiving a first frame from a first STA on a second frequency band, the first frame including at least one of first information about a specific channel in the first frequency band or second information about channel allocation in the first frequency band; and performing transmission or reception of a second frame with the first STA on the first frequency band based on at least one of the first information or the second information.

[0011] Technical Effects

[0012] According to the present disclosure, a method and apparatus for transmitting or receiving channel information about an operating frequency band in a WLAN system may be provided.

[0013] According to the present disclosure, a method and apparatus for transmitting or receiving channel information for frame exchange in another operating frequency band in a specific operating frequency band in a WLAN system may be provided.

[0014] Effects achievable by the present disclosure are not limited to the above-described effects, and other effects not described herein may be clearly understood by those skilled in the relevant art through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings, which are included as a part of the detailed description for understanding the present disclosure, provide embodiments of the present disclosure and describe technical features of the present disclosure together with the detailed description.

[0016] Figure 1 A block diagram illustrating a configuration of a wireless communication device according to an embodiment of the present disclosure is illustrated.

[0017] Figure 2 is a diagram illustrating an exemplary structure of a WLAN system to which the present disclosure can be applied.

[0018] Figure 3 This is a diagram for explaining a link establishment process to which the present disclosure can be applied.

[0019] Figure 4 This is a diagram for explaining a backoff process to which the present disclosure can be applied.

[0020] Figure 5 This is a diagram for explaining a frame transmission operation based on CSMA / CA to which the present disclosure can be applied.

[0021] Figure 6 is a diagram for explaining an example of a frame structure used in a WLAN system to which the present disclosure can be applied.

[0022] Figure 7 is a diagram illustrating an example of a PPDU defined in the IEEE 802.11 standard to which the present disclosure can be applied.

[0023] Figure 8 FIG. 1 is a diagram illustrating an example of a region where channelization of a millimeter wave band according to the present disclosure can be applied.

[0024] Figure 9 is a flowchart for explaining an example of a method for transmitting channel information about an operating frequency band according to the present disclosure.

[0025] Figure 10 is a flowchart for explaining an example of a method for receiving channel information about an operating frequency band according to the present disclosure. DETAILED DESCRIPTION

[0026] Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description disclosed with the accompanying drawings is intended to describe exemplary embodiments of the present disclosure and is not intended to represent the only embodiment in which the present disclosure may be implemented. The following detailed description includes specific details to provide a complete understanding of the present disclosure. However, those skilled in the relevant art will appreciate that the present disclosure may be implemented without these specific details.

[0027] In some cases, well-known structures and devices may be omitted, or may be shown in the form of block diagrams based on the core functions of each structure and device in order to prevent ambiguity in the concepts of the present disclosure.

[0028] In the present disclosure, when an element is referred to as being "connected," "combined," or "linked" to another element, it may include an indirect connection relationship in which another element exists therebetween as well as a direct connection relationship. In addition, in the present disclosure, the terms "comprising" or "having" specify the presence of the mentioned features, steps, operations, components, and / or elements, but do not preclude the presence or addition of one or more other features, steps, operations, components, elements, and / or groups thereof.

[0029] In the present disclosure, terms such as "first," "second," etc. are used only to distinguish one element from another and are not used to limit the elements. Unless otherwise specified, they do not limit the order or importance of the elements. Therefore, within the scope of the present disclosure, the first element in one embodiment may be referred to as the second element in another embodiment, and similarly, the second element in one embodiment may be referred to as the first element in another embodiment.

[0030] The terms used in this disclosure are intended to describe specific embodiments and not to limit the claims. As used in the description of the embodiments and the appended claims, the singular is intended to include the plural, unless the context clearly indicates otherwise. The term "and / or" used in this disclosure may refer to one of the relevant enumerated items, or mean that it refers to and includes any and all possible combinations of two or more of them. In addition, unless otherwise indicated, the " / " between words in this disclosure has the same meaning as "and / or".

[0031] Examples of the present disclosure can be applied to various wireless communication systems. For example, examples of the present disclosure can be applied to wireless LAN systems. For example, examples of the present disclosure can be applied to wireless LANs based on IEEE 802.11a / g / n / ac / ax standards. In addition, examples of the present disclosure can be applied to wireless LANs based on the newly proposed IEEE 802.11be (or EHT) standard. Examples of the present disclosure can be applied to wireless LANs based on the IEEE802.11be version 2 standard corresponding to the additional enhanced technology of the IEEE 802.11be version 1 standard. In addition, examples of the present disclosure can be applied to wireless LANs based on the next generation standard after IEEE 802.11be. In addition, examples of the present disclosure can be applied to cellular wireless communication systems. For example, it can be applied to cellular wireless communication systems based on long term evolution (LTE) technology and 5G new radio (NR) technology based on the third generation partnership project (3GPP) standard.

[0032] Hereinafter, technical features of examples to which the present disclosure can be applied will be described.

[0033] Figure 1 A block diagram of a wireless communication device according to an embodiment of the present disclosure is illustrated.

[0034] Figure 1 The first device 100 and the second device 200 illustrated in the specification may be replaced with various terms such as a terminal, a wireless device, a wireless transmit / receive unit (WTRU), a user equipment (UE), a mobile station (MS), a user terminal (UT), a mobile subscriber station (MSS), a mobile subscriber unit (MSU), a subscriber station (SS), an advanced mobile station (AMS), a wireless terminal (WT), or a simple user. In addition, the first device 100 and the second device 200 include an access point (AP), a base station (BS), a fixed station, a node B, a base transceiver system (BTS), and a network. It may be replaced with various terms such as an artificial intelligence (AI) system, a roadside unit (RSU), a repeater, a router, a relay, and a gateway.

[0035] Figure 1The devices 100 and 200 illustrated in FIG. 1 may be referred to as stations (STAs). For example, Figure 1 The devices 100 and 200 illustrated in the accompanying drawings may be referred to by various terms such as a transmitting device, a receiving device, a transmitting STA, and a receiving STA. For example, the STAs 110 and 200 may perform an access point (AP) role or a non-AP role. That is, in the present disclosure, the STAs 110 and 200 may perform AP and / or non-AP functions. When the STAs 110 and 200 perform AP functions, they may be simply referred to as APs, and when the STAs 110 and 200 perform non-AP functions, they may be simply referred to as STAs. In addition, in the present disclosure, an AP may also be referred to as an AP STA.

[0036] Reference Figure 1 , the first device 100 and the second device 200 can transmit and receive radio signals through various wireless LAN technologies (e.g., IEEE 802.11 series). The first device 100 and the second device 200 can include interfaces for a media access control (MAC) layer and a physical layer (PHY) that conform to the IEEE 802.11 standard.

[0037] In addition to wireless LAN technology, the first device 100 and the second device 200 can also support various communication standards (e.g., 3GPP LTE series, 5G NR series standards, etc.). In addition, the device of the present disclosure can be implemented in various devices such as mobile phones, vehicles, personal computers, augmented reality (AR) devices, and virtual reality (VR) devices. In addition, the STA of this specification can support various communication services such as voice calls, video calls, data communications, autonomous driving, machine type communication (MTC), machine-to-machine (M2M), device-to-device (D2D), IoT (Internet of Things), etc.

[0038] The first device 100 may include one or more processors 102 and one or more memories 104, and may further include one or more transceivers 106 and / or one or more antennas 108. The processor 102 may control the memory 104 and / or the transceiver 106 and may be configured to implement the descriptions, functions, processes, suggestions, methods, and / or operational flowcharts included in this disclosure. For example, the processor 102 may generate first information / signals by processing information in the memory 104 and then transmit a wireless signal including the first information / signals via the transceiver 106. Alternatively, the processor 102 may receive a wireless signal including second information / signals via the transceiver 106 and then store information obtained through signal processing of the second information / signals in the memory 104. The memory 104 may be connected to the processor 102 and may store various information related to the operation of the processor 102. For example, the memory 104 may store software code including instructions for executing all or part of the processing controlled by the processor 102 or for executing the descriptions, functions, processes, suggestions, methods, and / or operational flowcharts included in this disclosure. Here, the processor 102 and the memory 104 may be part of a communication modem / circuit / chip designed to implement wireless LAN technology (e.g., the IEEE 802.11 series). The transceiver 106 may be connected to the processor 102 and may transmit and / or receive wireless signals via one or more antennas 108. The transceiver 106 may include a transmitter and / or a receiver. The transceiver 106 may be used in conjunction with an RF (radio frequency) unit. In the present disclosure, a wireless device may refer to a communication modem / circuit / chip.

[0039] The second device 200 may include one or more processors 202 and one or more memories 204, and may further include one or more transceivers 206 and / or one or more antennas 208. The processor 202 may control the memory 204 and / or the transceiver 206 and may be configured to implement the descriptions, functions, processes, suggestions, methods, and / or operational flowcharts included in this disclosure. For example, the processor 202 may generate third information / signals by processing information in the memory 204, and then transmit a wireless signal including the third information / signals via the transceiver 206. Alternatively, the processor 202 may receive a wireless signal including fourth information / signals via the transceiver 206, and then store information obtained from signal processing of the fourth information / signals in the memory 204. The memory 204 may be connected to the processor 202 and may store various information related to the operation of the processor 202. For example, the memory 204 may store software code including instructions for executing all or part of the processing controlled by the processor 202 or for executing the descriptions, functions, processes, suggestions, methods, and / or operational flowcharts included in this disclosure. Here, the processor 202 and the memory 204 may be part of a communication modem / circuit / chip designed to implement wireless LAN technology (e.g., IEEE 802.11 series). The transceiver 206 may be connected to the processor 202 and may transmit and / or receive wireless signals via one or more antennas 208. The transceiver 206 may include a transmitter and / or a receiver. The transceiver 206 may be used in conjunction with an RF unit. In the present disclosure, a device may refer to a communication modem / circuit / chip.

[0040] In the following, the hardware elements of the apparatus 100, 200 will be described in more detail. Without limitation, one or more protocol layers may be implemented by one or more processors 102, 202. For example, one or more processors 102, 202 may implement one or more layers (e.g., functional layers such as PHY, MAC). One or more processors 102, 202 may generate one or more PDUs (Protocol Data Units) and / or one or more SDUs (Service Data Units) according to the descriptions, functions, processes, suggestions, methods, and / or operational flowcharts disclosed in the present disclosure. One or more processors 102, 202 may generate messages, control information, data, or information according to the descriptions, functions, processes, suggestions, methods, and / or operational flowcharts disclosed in the present disclosure. One or more processors 102, 202 may generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the functions, processes, suggestions, and / or methods disclosed in the present disclosure to provide them to one or more transceivers 106, 206. One or more processors 102, 202 may receive signals (e.g., baseband signals) from one or more transceivers 106, 206 and obtain PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, processes, suggestions, methods, and / or operational flow diagrams included in the present disclosure.

[0041] The one or more processors 102, 202 may be referred to as controllers, microcontrollers, microprocessors, or microcomputers. The one or more processors 102, 202 may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more ASICs (Application Specific Integrated Circuits), one or more DSPs (Digital Signal Processors), one or more DSPDs (Digital Signal Processing Devices), one or more PLDs (Programmable Logic Devices), or one or more FPGAs (Field Programmable Gate Arrays) may be included in the one or more processors 102, 202. The descriptions, functions, processes, suggestions, methods, and / or operational flowcharts included in the present disclosure may be implemented using firmware or software, and the firmware or software may be implemented to include modules, processes, functions, etc. The firmware or software configured to execute the descriptions, functions, processes, suggestions, methods, and / or operational flowcharts included in the present disclosure may be included in the one or more processors 102, 202, or may be stored in one or more memories 104, 204 and driven by the one or more processors 102, 202. The descriptions, functions, processes, suggestions, methods and / or operational flow charts included in the present disclosure may be implemented using firmware or software in the form of codes, instructions and / or instruction sets.

[0042] One or more memories 104, 204 can be connected to one or more processors 102, 202 and can store data, signals, messages, information, programs, codes, instructions, and / or commands in various forms. One or more memories 104, 204 can be configured with ROM, RAM, EPROM, flash memory, hard drive, registers, cache memory, computer-readable storage media, and / or combinations thereof. One or more memories 104, 204 can be located internally and / or externally to one or more processors 102, 202. In addition, one or more memories 104, 204 can be connected to one or more processors 102, 202 via various technologies such as wired or wireless connections.

[0043] One or more transceivers 106, 206 may transmit user data, control information, wireless signals / channels, etc., as described in the methods and / or operational flowcharts, etc., of the present disclosure to one or more other devices. One or more transceivers 106, 206 may receive user data, control information, wireless signals / channels, etc., as described, functions, processes, suggestions, methods, and / or operational flowcharts, etc., included in the present disclosure from one or more other devices. For example, one or more transceivers 106, 206 may be connected to one or more processors 102, 202 and may transmit and receive wireless signals. For example, one or more processors 102, 202 may control one or more transceivers 106, 206 to transmit user data, control information, or wireless signals to one or more other devices. In addition, one or more processors 102, 202 may control one or more transceivers 106, 206 to receive user data, control information, or wireless signals from one or more other devices. In addition, one or more transceivers 106, 206 may be connected to one or more antennas 108, 208, and one or more transceivers 106, 206 may be configured to transmit and receive user data, control information, wireless signals / channels, etc. mentioned in the descriptions, functions, processes, suggestions, methods, and / or operational flowcharts, etc. included in the present disclosure through one or more antennas 108, 208. In the present disclosure, one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers 106, 206 may convert received wireless signals / channels, etc. from RF band signals into baseband signals to process the received user data, control information, wireless signals / channels, etc. by using one or more processors 102, 202. One or more transceivers 106, 206 may convert user data, control information, wireless signals / channels, etc. processed by using one or more processors 102, 202 from baseband signals into RF band signals. Thus, one or more transceivers 106 , 206 may include (analog) oscillators and / or filters.

[0044] For example, one of the STAs 100 and 200 may perform the intended operation of an AP, and the other of the STAs 100 and 200 may perform the intended operation of a non-AP STA. Figure 1 The transceivers 106 and 206 can perform signal transmission and reception operations (e.g., packets or physical layer protocol data units (PPDUs) compliant with IEEE 802.11a / b / g / n / ac / ax / be / bn). In addition, in the present disclosure, operations of various STAs generating transmission / reception signals or performing data processing or calculations on transmission / reception signals in advance can be performed by Figure 1The processors 102 and 202 of the STA may execute the operations of generating a transmit / receive signal or performing data processing or calculation for the transmit / receive signal in advance. For example, examples of operations of generating a transmit / receive signal or performing data processing or calculation for the transmit / receive signal in advance may include: 1) determining / acquiring / configuring / calculating / decoding / encoding bit information of fields (signal (SIG), short training field (STF), long training field (LTF), data, etc.) included in the PPDU; 2) determining / configuring / acquiring time resources or frequency resources (e.g., subcarrier resources) used for fields (SIG, STF, LTF, data, etc.) included in the PPDU; 3) determining / configuring / acquiring specific sequences (e.g., pilot sequences, STF / LTF sequences, additional sequences applied to SIG) for fields (SIG, STF, LTF, data, etc.) included in the PPDU action; 4) power control operations and / or power saving operations applied to STAs; 5) operations related to determining / acquiring / configuring / calculating / decoding / encoding of ACK signals, etc. In addition, in the following example, various information used by various STAs to determine / acquire / configure / calculate / decode / encode transmission signals and reception signals (e.g., information related to fields / subfields / control fields / parameters / power, etc.) may be stored in Figure 1 in memories 104 and 204.

[0045] Hereinafter, the downlink (DL) may refer to a link used for communication from an AP STA to a non-AP STA, and DL PPDUs / packets / signals may be transmitted and received via the DL. In DL communication, the transmitter may be part of an AP STA, and the receiver may be part of a non-AP STA. The uplink (UL) may refer to a link used for communication from a non-AP STA to an AP STA, and UL PPDUs / packets / signals may be transmitted and received via the UL. In UL communication, the transmitter may be part of a non-AP STA, and the receiver may be part of an AP STA.

[0046] Figure 2 is a diagram illustrating an exemplary structure of a wireless LAN system to which the present disclosure can be applied.

[0047] The structure of a wireless LAN system can be composed of multiple components. The interaction of multiple components can provide a wireless LAN that supports STA mobility that is transparent to upper layers. The basic service set (BSS) corresponds to the basic building block of a wireless LAN. Figure 2 It is exemplarily shown that two BSSs (BSS1 and BSS2) exist, and two STAs are included as members of each BSS (STA1 and STA2 are included in BSS1, and STA3 and STA4 are included in BSS2). Figure 2The ellipse representing the BSS in the figure can also be understood as representing the coverage area in which the STAs included in the corresponding BSS maintain communication. This area can be called the basic service area (BSA). When a STA moves outside the BSA, it cannot communicate directly with other STAs in the BSA.

[0048] If you don't consider Figure 2 , the most basic BSS type in a wireless LAN is an independent BSS (IBSS). For example, an IBSS may have a minimum form containing only two STAs. For example, assuming that other components are omitted, BSS1 containing only STA1 and STA2 or BSS2 containing only STA3 and STA4 may respectively correspond to representative examples of IBSSs. This configuration is possible when STAs can communicate directly without an AP. In addition, in this type of wireless LAN, it is not pre-configured but can be configured when a LAN is needed, and this may be referred to as an ad-hoc network. Since the IBSS does not include an AP, there is no centralized management entity. That is, in an IBSS, STAs are managed in a distributed manner. In an IBSS, all STAs may be composed of mobile STAs, and access to the distributed system (DS) is not allowed, thereby forming a self-contained network.

[0049] The membership of a STA in a BSS can be changed dynamically by turning the STA on or off, entering or exiting a BSS region, etc. To become a member of a BSS, a STA can join the BSS using a synchronization process. To access all services of the BSS infrastructure, a STA must associate with the BSS. This association can be established dynamically and can include the use of a distributed system service (DSS).

[0050] The direct STA-to-STA distance in a wireless LAN may be limited by PHY performance. In some cases, this distance limit may be sufficient, but in some cases, communication between STAs at longer distances may be required. A distributed system (DS) can be configured to support extended coverage.

[0051] DS refers to the structure of BSS interconnection. Specifically, Figure 2As shown, the BSS can exist as an extended form of a network composed of multiple BSSs. DS is a logical concept and can be specified by the characteristics of the distributed system medium (DSM). At this point, the wireless medium (WM) and the DSM can be logically separated. Each logical medium is used for a different purpose and is used by different components. These media are not limited to being the same, nor are they limited to being different. In this way, the flexibility of the wireless LAN structure (DS structure or other network structure) can be interpreted as multiple media being logically different. That is, the wireless LAN structure can be implemented in various ways, and the corresponding wireless LAN structure can be independently specified by the physical characteristics of each embodiment.

[0052] DS can support mobile devices by providing seamless integration of multiple BSSs and providing the logical services necessary to address the address leading to the destination. In addition, DS can also include a component called a portal, which is used as a bridge for connections between wireless LANs and other networks (e.g., IEEE 802.X).

[0053] The AP enables associated non-AP STAs to access the DS through the WM and means an entity that also has STA functionality. Data movement between the BSS and the DS can be performed through the AP. For example, Figure 2 STA2 and STA3 shown in the figure have STA functionality and provide functionality allowing associated non-AP STAs (STA1 and STA4) to access the DS. Furthermore, since all APs essentially correspond to STAs, all APs are addressable entities. The addresses used by APs for communication on the WM are not necessarily the same as the addresses used by APs for communication on the DSM. A BSS consisting of an AP and one or more STAs may be referred to as an infrastructure BSS.

[0054] Data sent from one of the STAs associated with the AP to the STA address of the corresponding AP can always be received at the uncontrolled port and can be processed by the IEEE 802.1X port access entity. In addition, when the controlled port is authenticated, the transmitted data (or frame) can be delivered to the DS.

[0055] In addition to the above-mentioned structure of the DS, an extended service set (ESS) can also be configured to provide wide coverage.

[0056] An ESS refers to a network of arbitrary size and complexity consisting of a DS and a BSS. An ESS may correspond to a set of BSSs connected to one DS. However, an ESS does not include a DS. An ESS network is characterized by being considered an IBSS in the Logical Link Control (LLC) layer. STAs included in an ESS can communicate with each other, and mobile STAs can move from one BSS to another (within the same ESS) transparently to the LLC. APs included in an ESS may have the same service set identifier (SSID). The SSID is distinguished from the BSSID, which is an identifier of a BSS.

[0057] The wireless LAN system does not assume anything about the relative physical location of the BSSs, and all of the following forms are possible. BSSs can partially overlap, which is a form commonly used to provide continuous coverage. In addition, BSSs may not be physically connected, and logically, there is no limit on the distance between BSSs. In addition, BSSs can be physically located in the same location, which can be used to provide redundancy. In addition, one (or more than one) IBSS or ESS networks can physically exist in the same space as one (or more than one) ESS networks. When an ad hoc network operates in a location where an ESS network exists, when physically overlapping wireless networks are configured by different organizations, or when two or more different access and security policies are required in the same location, this can correspond to the form of an ESS network, etc.

[0058] Figure 3 is a diagram for explaining a link establishment process to which the present disclosure can be applied.

[0059] In order for a STA to establish a link with the network and send / receive data, it first discovers the network, performs authentication, establishes an association, and, for security reasons, performs authentication processing. The link establishment process may also be referred to as the session initiation process or the session establishment process. Furthermore, the discovery, authentication, association, and security establishment processes of the link establishment process may be collectively referred to as the association process.

[0060] In step S310, the STA may perform a network discovery operation. The network discovery operation may include a scanning operation by the STA. In other words, in order for the STA to access the network, it needs to find a network it can participate in. The STA should identify compatible networks before participating in a wireless network, and the process of identifying networks existing in a specific area is called scanning.

[0061] Scanning schemes include active scanning and passive scanning. Figure 3The network discovery operation including the active scanning process is exemplarily illustrated. In active scanning, the STA performing the scan sends a probe request frame to discover which APs exist around it while moving through the channel and waits for responses thereto. The responder sends a probe response frame as a response to the probe request frame to the STA that has sent the probe request frame. Here, the responder may be the STA that last sent a beacon frame in the BSS of the channel being scanned. In the BSS, since the AP sends a beacon frame, the AP becomes the responder, and in the IBSS, the STAs in the IBSS rotate to send beacon frames, so the responder is not constant. For example, a STA that sends a probe request frame on channel 1 and receives a probe response frame on channel 1 can store the BSS-related information included in the received probe response frame, and can move to the next channel (e.g., channel 2) and perform scanning in the same manner (i.e., sending and receiving probe requests / responses on channel 2).

[0062] Although not in Figure 3 Although not shown in FIG, a scanning operation can be performed in a passive scanning manner. In passive scanning, a scanning STA waits for a beacon frame while moving across channels. A beacon frame is one of the management frames defined in IEEE 802.11 and is periodically transmitted to notify the existence of a wireless network and allow a scanning STA to find and participate in the wireless network. In a BSS, an AP is used to periodically transmit beacon frames, and in an IBSS, STAs within the IBSS rotate to transmit beacon frames. When a scanning STA receives a beacon frame, the STA stores the BSS information included in the beacon frame and, while moving to another channel, records the beacon frame information in each channel. The STA that receives the beacon frame can store the BSS-related information included in the received beacon frame, move to the next channel, and perform scanning in the next channel in the same manner. Comparing active scanning with passive scanning, the advantage of active scanning is that it has less latency and consumes less power than passive scanning.

[0063] After the STA discovers the network, an authentication process may be performed at step S320. In order to clearly distinguish it from the security establishment operation of step S340 to be described later, this authentication process may be referred to as a first authentication process.

[0064] The authentication process includes the following process: the STA sends an authentication request frame to the AP, and in response thereto, the AP sends an authentication response frame to the STA. The authentication frame used for authentication request / response corresponds to a management frame.

[0065] The authentication frame includes an authentication algorithm number, an authentication transaction sequence number, a status code, a challenge text, a robust security network (RSN), a limited cycle group, etc. This corresponds to some examples of information that can be included in the authentication request / response frame, and can be replaced with other information, or additional information can be included.

[0066] The STA can send an authentication request frame to the AP. The AP can determine whether to allow authentication of the corresponding STA based on the information included in the received authentication request frame. The AP can provide the result of the authentication process to the STA via an authentication response frame.

[0067] After the STA is successfully authenticated, an association process may be performed at step S330. The association process includes the following processes: the STA sends an association request frame to the AP, and in response, the AP sends an association response frame to the STA.

[0068] For example, the association request frame may include information related to various capabilities, a beacon listening interval, a service set identifier (SSID), supported rates, supported channels, RSN, mobility domain, supported operation categories, a traffic indication map broadcast request (TIM broadcast request), interworking service capabilities, etc. For example, the association response frame may include information related to various capabilities, a status code, an association ID (AID), supported rates, an enhanced distributed channel access (EDCA) parameter set, a received channel power indicator (RCPI), a received signal-to-noise ratio indicator (RSNI), mobility domain, a timeout interval (e.g., association recovery time), overlapping BSS scan parameters, a TIM broadcast response, a quality of service (QoS) map, etc. This corresponds to some examples of information that may be included in the association request / response frame and may be replaced with other information or may further include additional information.

[0069] After the STA successfully associates with the network, a security establishment process may be performed at step S340. The security establishment process at step S340 may be referred to as an authentication process through a Robust Security Network Association (RSNA) request / response, the authentication process at step S320 may be referred to as a first authentication process, and the security establishment process at step S340 may also be referred to simply as an authentication process.

[0070] The security establishment process of step S340 may include, for example, a process of establishing a private key using a four-way handshake through an Extensible Authentication Protocol over LAN (EAPOL) frame. Alternatively, the security establishment process may be performed according to a security scheme not defined in the IEEE 802.11 standard.

[0071] Figure 4 It is a diagram for explaining a backoff process to which the present disclosure can be applied.

[0072] In wireless LAN systems, the basic access mechanism for medium access control (MAC) is the Carrier Sense Multiple Access with Collision Avoidance (CSMA / CA) mechanism. The CSMA / CA mechanism is also known as the Distributed Coordination Function (DCF) of the IEEE 802.11 MAC and essentially employs a "listen before talk" access mechanism. According to this type of access mechanism, before starting transmission, the AP and / or STA may perform Explicit Channel Assessment (CCA) to sense the radio channel or medium during a predetermined time interval (e.g., the DCF Interframe Space (DIFS)). As a result of this sensing, if the medium is determined to be idle, frame transmission is initiated via the corresponding medium. On the other hand, if the medium is detected to be occupied or busy, the corresponding AP and / or STA does not initiate its own transmission and may set a delay period for medium access (e.g., a random backoff period) and attempt frame transmission after the wait. By applying a random backoff period, collisions can be minimized because multiple STAs are expected to attempt frame transmission after waiting for different time periods.

[0073] In addition, the IEEE 802.11 MAC protocol provides a hybrid coordination function (HCF). HCF is based on DCF and point coordination function (PCF). PCF is a synchronous access method based on polling, and refers to a method in which all receiving APs and / or STAs periodically poll to receive data frames. In addition, HCF has enhanced distributed channel access (EDCA) and HCF controlled channel access (HCCA). EDCA is a contention-based access method that provides data frames to multiple users in a direction, and HCCA uses a non-contention-based channel access method that utilizes a polling mechanism. In addition, HCF includes a medium access mechanism for improving the QoS (quality of service) of a wireless LAN, and QoS data can be sent in a contention period (CP) and a contention-free period (CFP).

[0074] Reference Figure 4, the operation based on the random backoff period will be described. When the occupied / busy medium becomes idle, multiple STAs can attempt to send data (or frames). As a method of minimizing collisions, each of the STAs can select a random backoff count respectively and attempt to send after waiting for the corresponding time slot time. The random backoff count has a pseudo-random integer value and can be determined as one of the values ​​ranging from 0 to CW. Here, CW is the contention window parameter value. The CW parameter is given CWmin as an initial value, but can take a value twice as large in the event of a transmission failure (for example, when an ACK for the transmitted frame is not received). When the CW parameter value reaches CWmax, data transmission can be attempted while maintaining the CWmax value until the data transmission is successful, and when the data transmission is successful, the CWmin value is reset. The values ​​of CW, CWmin and CWmax are preferably set to 2n-1 (n=0, 1, 2, ...).

[0075] When the random backoff process starts, the STA continuously monitors the medium during the backoff slot countdown according to the determined backoff count value. When the medium is monitored for occupancy, it stops the countdown and waits, and restarts the remaining countdown when the medium becomes idle.

[0076] exist Figure 4 In the example shown, when a packet to be transmitted arrives at STA3's MAC, STA3 can immediately transmit a frame after confirming that the medium has been idle for DIFS. The remaining STAs monitor and wait for the medium to become occupied / busy. Meanwhile, data to be transmitted can also occur at each of STA1, STA2, and STA5. When the medium is detected as idle, each STA waits for DIFS and then begins counting down the backoff slot based on a random backoff count value selected by each STA. Assume that STA2 selects the minimum backoff count value and STA1 selects the maximum backoff count value. This example illustrates a situation where, when STA2 completes the backoff count and begins frame transmission, STA5's remaining backoff time is shorter than STA1's. STA1 and STA5 temporarily stop the countdown and wait while STA2 occupies the medium. When STA2's occupation ends and the medium becomes idle again, STA1 and STA5 wait for DIFS and restart the backoff count where they left off. This means that frame transmission can begin after counting down the remaining backoff slots for the remaining backoff time. Since STA5's remaining backoff time is shorter than STA1's, STA5 begins frame transmission. While STA2 is occupying the medium, data transmission can also occur in STA4. From STA4's perspective, when the medium becomes idle, STA4 can wait for DIFS, then perform a countdown based on a random backoff count value selected by STA4 and begin frame transmission. Figure 4The example shows a situation where STA5's remaining backoff time accidentally conflicts with STA4's random backoff count value. In this case, a collision may occur between STA4 and STA5. When a collision occurs, neither STA4 nor STA5 receives an ACK, and data transmission fails. In this case, STA4 and STA5 can double the CW value, select a random backoff count value, and perform a countdown. While the medium is occupied by STA4 and STA5's transmissions, STA1 waits. When the medium becomes idle, STA1 waits DIFS and then begins frame transmission after the remaining backoff time has elapsed.

[0077] As in Figure 4 In the example, a data frame is a frame used to transmit data forwarded to a higher layer and can be transmitted after a backoff is performed after a DIFS period has elapsed since the medium became idle. Furthermore, a management frame is a frame used to exchange management information that is not forwarded to a higher layer and is transmitted after a backoff is performed after an IFS period, such as a DIFS period or a Point Coordination Function (PIFS) period. Subtypes of management frames include beacons, association request / responses, reassociation request / responses, probe request / responses, and authentication request / responses. Control frames are frames used to control access to the medium. Subtypes of control frames include request to send (RTS), clear to send (CTS), acknowledgement (ACK), power save poll (PS-Poll), block ACK (BlockAck), block ACK request (BlockACKReq), null data packet announcement (NDP announcement), and triggers. If a control frame is not a response frame to the previous frame, it is transmitted after a backoff is performed after a DIFS period has elapsed. If it is a response frame to the previous frame, it is transmitted without a backoff after a short IFS period (SIFS) has elapsed. The type and subtype of a frame may be identified by the type field and subtype field in the frame control (FC) field.

[0078] A Quality of Service (QoS) STA can perform a backoff after the arbitration IFS (AIFS) for the access category (AC) to which the frame belongs (i.e., AIFS (where i is a value determined by the AC)) and then transmit the frame. Here, frames that can use AIFS may be data frames, management frames, or control frames, rather than response frames.

[0079] Figure 5 is a diagram for explaining a frame transmission operation based on CSMA / CA to which the present disclosure can be applied.

[0080] As described above, in addition to physical carrier sensing in which STAs directly sense the medium, the CSMA / CA mechanism also includes virtual carrier sensing. Virtual carrier sensing is intended to compensate for problems such as hidden node problems that may occur in medium access. For virtual carrier sensing, the STA's MAC can use a network allocation vector (NAV). NAV is a value that indicates to other STAs the remaining time until the medium is available for use by STAs that are currently using or have the right to use the medium. Therefore, the value set to NAV corresponds to the period during which the STA sending the frame plans to use the medium, and during the corresponding period, the STA receiving the NAV value is prohibited from accessing the medium. For example, NAV can be configured based on the value of the "Duration" field of the MAC header of the frame.

[0081] exist Figure 5 In the example of FIG, it is assumed that STA1 intends to send data to STA2, and STA3 is in a position to be able to eavesdrop on some or all frames sent and received between STA1 and STA2.

[0082] In order to reduce the possibility of transmission collisions between multiple STAs in the CSMA / CA-based frame transmission operation, a mechanism using RTS / CTS frames can be applied. Figure 5 In the example of , when STA1 is transmitting, as a result of STA3's carrier sensing, it can be determined that the medium is in an idle state. That is, STA1 may correspond to a hidden node with respect to STA3. Alternatively, in Figure 5 In the example shown in FIG1 , it can be determined that the medium is idle based on STA3's carrier sensing result while STA2 is transmitting. In other words, STA2 may correspond to a hidden node with respect to STA3. By exchanging RTS / CTS frames before data transmission and reception between STA1 and STA2, STAs outside the transmission range of either STA1 or STA2, or outside the carrier sensing range of STA1 or STA3's transmission, can avoid attempting to occupy the channel during data transmission and reception between STA1 and STA2.

[0083] Specifically, STA1 can determine whether a channel is in use through carrier sensing. In terms of physical carrier sensing, STA1 can determine the channel occupancy idle state based on the energy level or signal correlation detected in the channel. In addition, in terms of virtual carrier sensing, STA1 can use the network allocation vector (NAV) timer to determine the channel occupancy state.

[0084] When the channel is idle for DIFS, STA1 may send an RTS frame to STA2 after backoff. When STA2 receives the RTS frame, STA2 may send a CTS frame to STA1 as a response to the RTS frame after SIFS.

[0085] If STA3 cannot overhear a CTS frame from STA2 but can overhear an RTS frame from STA1, STA3 can use the duration information included in the RTS frame to set the NAV timer for the subsequent frame transmission period (e.g., SIFS + CTS frame + SIFS + data frame + SIFS + ACK frame). Alternatively, if STA3 can overhear a CTS frame from STA2, even if STA3 cannot overhear an RTS frame from STA1, STA3 can use the duration information included in the CTS frame to set the NAV timer for the subsequent frame transmission period (e.g., SIFS + data frame + SIFS + ACK frame). In other words, if STA3 can overhear one or more of the RTS or CTS frames from one or more of STA1 or STA2, STA3 can set the NAV accordingly. When STA3 receives a new frame before the NAV timer expires, STA3 can update the NAV timer using the duration information included in the new frame. STA3 does not attempt channel access until the NAV timer expires.

[0086] When STA1 receives a CTS frame from STA2, STA1 can send a data frame to STA2 after SIFS, starting from the time the CTS frame is received. When STA2 successfully receives the data frame, STA2 can send an ACK frame to STA1 after SIFS as a response to the data frame. When the NAV timer expires, STA3 can determine whether the channel is in use through carrier sensing. If STA3 determines that the channel is not in use by other terminals during the DIFS period after the NAV timer expires, STA3 can attempt channel access after the contention window (CW) based on random backoff has expired.

[0087] Figure 6 is a diagram for explaining an example of a frame structure used in a WLAN system to which the present disclosure can be applied.

[0088] The PHY layer can prepare the MAC PDU (MPDU) to be transmitted with the help of instructions or primitives (meaning a set of instructions or parameters) from the MAC layer. For example, when a command requesting the PHY layer to start transmission is received from the MAC layer, the PHY layer switches to transmit mode, configures the information provided by the MAC layer (e.g., data) in the form of a frame, and transmits it. In addition, when the PHY layer detects a valid preamble of a received frame, the PHY layer monitors the header of the preamble and sends a command to the MAC layer to notify the PHY layer of the start of reception.

[0089] In this manner, information transmission / reception in the wireless LAN system is performed in the form of frames, and for this purpose, a PHY layer protocol data unit (PPDU) format is defined.

[0090] The basic PPDU may include a short training field (STF), a long training field (LTF), a signal (SIG) field, and a data (Data) field. Figure 7 The non-HT (high throughput) field shown in FIG may consist only of the legacy-STF (L-STF), legacy-LTF (L-LTF), legacy-SIG (L-SIG) field, and the data field. In addition, depending on the type of PPDU format (e.g., HT mixed format PPDU, HT greenfield format PPDU, VHT (very high throughput) PPDU, etc.), an additional (or different type) RL-SIG, U-SIG, non-legacy SIG field, non-legacy STF, non-legacy LTF (i.e., xx-SIG, xx-STF, xx-LTF (e.g., xx is HT, VHT, HE, EHT, etc.)) may be included between the L-SIG field and the data field.

[0091] STF is a signal used for signal detection, automatic gain control (AGC), diversity selection, precise time synchronization, etc., and LTF is a signal used for channel estimation and frequency error estimation. STF and LTF can be called signals for synchronization and channel estimation of the OFDM physical layer.

[0092] The SIG field may include various information related to PPDU transmission and reception. For example, the L-SIG field consists of 24 bits and may include a 4-bit rate field, a 1-bit reserved bit, a 12-bit length field, a 1-bit parity field, and a 6-bit tail field. The RATE field may include information about the modulation and coding rate of the data. For example, the 12-bit length field may include information about the length or duration of the PPDU. For example, the value of the 12-bit length field may be determined based on the type of PPDU. For example, for non-HT, HT, VHT, or EHT PPDUs, the value of the length field may be determined as a multiple of 3. For example, for HEPPDUs, the value of the length field may be determined as a multiple of 3+1 or 3+2.

[0093] The data field may include a service (SERVICE) field, a physical layer service data unit (PSDU), and a PPDU tail bit, and may also include padding bits if necessary. Some bits of the service field may be used for synchronization of the descrambler at the receiving end. The PSDU corresponds to the MAC PDU defined in the MAC layer and may include data generated / used in the upper layer. The PPDU tail bit may be used to return the encoder to the 0 state. The padding bits may be used to adjust the length of the data field in predetermined units.

[0094] MAC PDU is defined according to various MAC frame formats, and a basic MAC frame consists of a MAC header, a frame body, and a frame check sequence (FCS). A MAC frame can be composed of MAC PDUs and transmitted / received through PSDU of the data portion of the PPDU format.

[0095] The MAC header includes a frame control field, a duration / ID field, an address field, and other fields. The frame control field may include control information required for frame transmission / reception. The duration / ID field may be set to the time for transmitting the corresponding frame, etc. For details on the sequence control, QoS control, and HT control subfields of the MAC header, refer to the IEEE 802.11 standard.

[0096] The Null Data PPDU (NDP) format refers to a PPDU format that does not include a data field. In other words, the NDP refers to a frame format that includes the PPDU preamble of the general PPDU format (i.e., the L-STF, L-LTF, L-SIG fields, and additional non-legacy SIG, non-legacy STF, and non-legacy LTF (if present)) and does not include the remaining portion (i.e., the data field).

[0097] Figure 7 is a diagram illustrating an example of a PPDU defined in the IEEE 802.11 standard to which the present disclosure can be applied.

[0098] In standards such as IEEE 802.11a / g / n / ac / ax, various types of PPDUs have been used. The basic PPDU format (IEEE 802.11a / g) includes L-LTF, L-STF, L-SIG, and data fields. The basic PPDU format may also be referred to as a non-HT PPDU format (e.g., Figure 7 (as shown in (a)).

[0099] Compared to the basic PPDU format, the HT PPDU format (IEEE 802.11n) additionally includes HT-SIG, HT-STF, and HT-LFT fields. Figure 7The HT PPDU format shown in (b) may be referred to as an HT mixed format. Furthermore, an HT greenfield format PPDU may be defined, and this corresponds to a format consisting of an HT-GF-STF, HT-LTF1, HT-SIG, one or more HT-LTFs, and a data field, excluding L-STF, L-LTF, and L-SIG (not shown).

[0100] Compared to the basic PPDU format, an example of the VHT PPDU format (IEEE 802.11ac) additionally includes VHTSIG-A, VHT-STF, VHT-LTF, and VHT-SIG-B fields (e.g., Figure 7 (as shown in (c)).

[0101] Compared to the basic PPDU format, an example of the HE PPDU format (IEEE 802.11ax) additionally includes a repeated L-SIG (RL-SIG), HE-SIG-A, HE-SIG-B, HE-STF, HE-LTF, a packet extension (PE) field (such as Figure 7 (d) of FIG). Some fields may be excluded or their lengths may vary according to the detailed example of the HE PPDU format. For example, the HE-SIG-B field is included in the HE PPDU format for multi-user (MU), and the HE-SIG-B is not included in the HE PPDU format for single user (SU). In addition, the HE trigger-based (TB) PPDU format does not include the HE-SIG-B, and the length of the HE-STF field may vary up to 8 μs. The extended range (HE ER) SU PPDU format does not include the HE-SIG-B field, and the length of the HE-SIG-A field may vary up to 16 μs. For example, the RL-SIG may be configured to be the same as the L-SIG. Based on the presence of the RL-SIG, the receiving STA may know whether the received PPDU is a HE PPDU or an EHT PPDU, which will be described later.

[0102] The EHT PPDU format may include Figure 7 (e) EHT MU (multi-user) and Figure 7 The EHT TB (trigger-based) PPDU in (f) of FIG. The EHT PPDU format is similar to the HE PPDU format in that it includes the RL-SIG following the L-SIG, but may include the U (Universal)-SIG, EHT-SIG, EHT-STF, and EHT-LTF following the RL-SIG.

[0103] Figure 7The EHT MU PPDU in (e) corresponds to a PPDU that carries one or more data (or PSDU) for one or more users. That is, the EHT MU PPDU can be used for both SU transmission and MU transmission. For example, the EHT MU PPDU can correspond to a PPDU for one receiving STA or multiple receiving STAs.

[0104] Compared with EHT MU PPDU, Figure 7 The EHT TB PPDU in (f) omits the EHT-SIG. A STA that receives a trigger for UL MU transmission (eg, a trigger frame or a triggered response schedule (TRS)) may perform UL transmission based on the EHT TB PPDU format.

[0105] The L-STF, L-LTF, L-SIG, RL-SIG, U-SIG (Universal Signal), and EHT-SIG fields may be coded and modulated so that even legacy STAs can attempt demodulation and decoding, and may be mapped based on a determined subcarrier frequency spacing (e.g., 312.5 kHz). These may be referred to as pre-EHT modulation fields. Subsequently, the EHT-STF, EHT-LTF, data, and PE fields may be coded and modulated so that STAs that successfully decode non-legacy SIGs (e.g., U-SIG and / or EHT-SIG) and obtain the information included in these fields may be demodulated and decoded, and may be mapped based on a determined subcarrier frequency spacing (e.g., 78.125 kHz). These may be referred to as EHT modulation fields.

[0106] Similarly, in the HE PPDU format, the L-STF, L-LTF, L-SIG, RL-SIG, HE-SIG-A, and HE-SIG-B fields may be referred to as pre-HE modulation fields, and the HE-STF, HE-LTF, data, and PE fields may be referred to as HE modulation fields. Furthermore, in the VHT PPDU format, the L-STF, L-LTF, L-SIG, and VHT-SIG-A fields may be referred to as non-VHT modulation fields, and the VHT STF, VHT-LTF, VHT-SIG-B, and data fields may be referred to as VHT modulation fields.

[0107] Included in Figure 7The U-SIG in the EHT PPDU format may be configured based on, for example, two symbols (e.g., two consecutive OFDM symbols). Each symbol used for the U-SIG (e.g., OFDM symbol) may have a duration of 4 μs, and the U-SIG may have a total duration of 8 μs. Each symbol of the U-SIG may be used to transmit 26 bits of information. For example, each symbol of the U-SIG may be transmitted and received based on 52 data tones and 4 pilot tones.

[0108] The U-SIG can be constructed in 20MHz units. For example, if an 80MHz PPDU is constructed, the U-SIG can be duplicated. That is, the same four U-SIGs can be included in the 80MHz PPDU. PPDUs with bandwidth exceeding 80MHz can include different U-SIGs.

[0109] For example, A uncoded bits may be transmitted via the U-SIG, the first symbol of the U-SIG (e.g., the U-SIG-1 symbol) may transmit the first X bits of information out of a total of A bits of information, and the second symbol of the U-SIG (e.g., the U-SIG-2 symbol) may transmit the remaining Y bits of information out of a total of A bits of information. The A bits of information (e.g., 52 uncoded bits) may include a CRC field (e.g., a 4-bit long field) and a tail field (e.g., a 6-bit long field). For example, the tail field may be used to terminate the trellis structure of the convolutional decoder and may be set to 0.

[0110] The bit information sent through U-SIG can be divided into version-independent bits and version-dependent bits. For example, U-SIG can be included in Figure 7 The U-SIG field format included in the EHT PPDU format and the U-SIG field included in the UHR PPDU format may be included in a new PPDU format (e.g., UHR PPDU format) not shown in the figure. The version-independent bits may be the same, and some or all of the version-dependent bits may be different.

[0111] For example, the size of the version-independent bit of the U-SIG can be fixed or variable. The version-independent bit can be assigned only to the U-SIG-1 symbol, or to both the U-SIG-1 symbol and the U-SIG-2 symbol. The version-independent bit and the version-dependent bit can be referred to by various names, such as the first control bit and the second control bit.

[0112] For example, the version-independent bits of the U-SIG may include a 3-bit physical layer version identifier (PHY version identifier), and this information may indicate the PHY version of the transmitted / received PPDU (e.g., EHT, UHR, etc.). The version-independent bits of the U-SIG may include a 1-bit UL / DL flag field. The first value of the 1-bit UL / DL flag field is related to UL communication, and the second value of the UL / DL flag field is related to DL communication. The version-independent bits of the U-SIG may include information about the length of a transmit opportunity (TXOP) and information about a BSS color ID.

[0113] For example, the version-related bits of the U-SIG may include information directly or indirectly indicating the type of the PPDU (eg, SU PPDU, MU PPDU, TB PPDU, etc.).

[0114] Information required for PPDU transmission and reception may be included in the U-SIG. For example, the U-SIG may also include information about bandwidth, information about the MCS technology applied to the non-legacy SIG (e.g., EHT-SIG or UHR-SIG, etc.), information indicating whether the DCM (Dual Carrier Modulation) technology (e.g., a technology for achieving an effect similar to frequency diversity by reusing the same signal on two subcarriers) is applied to the non-legacy SIG, information about the number of symbols used for the non-legacy SIG, and information about whether the non-legacy SIG is generated across the entire frequency band.

[0115] Some of the information required for PPDU transmission and reception may be included in the U-SIG and / or the non-legacy SIG (e.g., EHT-SIG or UHR-SIG, etc.). For example, information on the type of non-legacy LTF / STF (e.g., EHT-LTF / EHT-STF or UHR-LTF / UHR-STF, etc.), information on the length of the non-legacy LTF and the CP (Cyclic Prefix) length, information on the GI (Guard Interval) applicable to the non-legacy LTF, information on preamble puncturing applicable to the PPDU, information on resource unit (RU) allocation, etc. may be included only in the U-SIG, only in the non-legacy SIG, or may be indicated by a combination of information included in the U-SIG and information included in the non-legacy SIG.

[0116] Preamble puncturing may indicate transmission of a PPDU in which no signal exists in one or more frequency bins within the PPDU's bandwidth. For example, the size of a frequency bin (or the resolution of preamble puncturing) may be defined as 20 MHz, 40 MHz, etc. For example, preamble puncturing may be applied to a PPDU bandwidth of a predetermined size or greater.

[0117] exist Figure 7In the example of [ ], non-legacy SIGs such as HE-SIG-B and EHT-SIG may include control information for receiving STAs. A non-legacy SIG may be transmitted over at least one symbol, and one symbol may be 4 μs long. Information regarding the number of symbols used for the EHT-SIG may be included in a previous SIG (e.g., HE-SIG-A, U-SIG, etc.).

[0118] Non-legacy SIGs such as HE-SIG-B and EHT-SIG may include common fields and user-specific fields. The common fields and user-specific fields may be encoded separately.

[0119] In some cases, the common field can be omitted. For example, in compressed mode without OFDMA (Orthogonal Frequency Division Multiple Access), the common field can be omitted, and multiple STAs can receive the PPDU (e.g., the data field of the PPDU) on the same frequency band. In non-compressed mode with OFDMA, multiple users can receive the PPDU (e.g., the data field of the PPDU) on different frequency bands.

[0120] The number of user-specific fields may be determined based on the number of users. A user block field may include up to two user fields. Each user field may be associated with a MU-MIMO allocation or may be associated with a non-MU-MIMO allocation.

[0121] The common field may include a CRC bit and a tail bit, and the length of the CRC bit may be determined to be 4 bits, while the length of the tail bit may be determined to be 6 bits and set to 000000. The common field may include RU allocation information. The RU allocation information may include information about the positions of the RUs to which multiple users (i.e., multiple receiving STAs) are assigned.

[0122] A RU can include multiple subcarriers (or tones). RUs can be used when transmitting signals to multiple STAs based on OFDMA technology. In addition, RUs can be defined even when transmitting signals to a single STA. Resources can be allocated for non-legacy STFs, non-legacy LTFs, and data fields in units of RUs.

[0123] The applicable RU size can be defined based on the PPDU bandwidth. The RU can be defined identically or differently for the applied PPDU format (e.g., HEPPDU, EHT PPDU, UHR PPDU, etc.). For example, in the case of an 80MHz PPDU, the RU layout of the HEPPDU and EHT PPDU can be different. The applicable RU size, the number of RUs and RU positions, the DC (direct current) subcarrier position and number, the null subcarrier position and number, the guard subcarrier position and number, etc. for each PPDU bandwidth can be referred to as a tone plan. For example, a tone plan for high bandwidth can be defined in the form of multiple iterations of a low bandwidth tone plan.

[0124] RUs of various sizes can be defined as 26-tone RUs, 52-tone RUs, 106-tone RUs, 242-tone RUs, 484-tone RUs, 996-tone RUs, 2×996-tone RUs, 3×996-tone RUs, and the like. An MRU (Multi-RU) is distinct from multiple individual RUs and corresponds to a group of subcarriers consisting of multiple RUs. For example, an MRU can be defined as 52+26 tones, 106+26 tones, 484+242 tones, 996+484 tones, 996+484+242 tones, 2×996+484 tones, 3×996 tones, or 3×996+484 tones. In addition, the multiple RUs that make up an MRU may or may not be contiguous in the frequency domain.

[0125] The specific size of an RU can be reduced or expanded. Therefore, the specific size of each RU (i.e., the number of corresponding tones) in this disclosure is not restrictive but illustrative. In addition, in this disclosure, within a predetermined bandwidth (e.g., 20 MHz, 40 MHz, 80 MHz, 160 MHz, 320 MHz, etc.), the number of RUs can vary depending on the RU size.

[0126] Figure 7 The names of each field in the PPDU format are exemplary, and the scope of the present disclosure is not limited by these names. In addition, the examples of the present disclosure can be applied to Figure 7 The PPDU format shown in Figure 7 A new PPDU format that excludes some fields and / or adds some fields to the existing PPDU format.

[0127] Channel information about the operating band

[0128] The above description of the WLAN system can be mainly applied to WLAN systems operating in existing operating frequency bands (e.g., sub-7 GHz bands (e.g., 2.4 GHz, 5 GHz, or 6 GHz bands)). For example, the above PPDU format can be mainly applied to WLAN systems operating in sub-7 GHz bands. In addition, WLAN systems operating in high operating frequency bands (e.g., millimeter wave (mmWave) bands such as the 60 GHz band) have been defined.

[0129] Figure 8 FIG. 1 is a diagram illustrating an example of an area to which the channelization of the millimeter wave band of the present disclosure can be applied.

[0130] Figure 8 The example in Figure 1 shows the mmWave frequency bands used in the United States, the European Union, South Korea, Japan, Australia, and China, and shows the size and location of the channels defined in the corresponding frequency bands. For example, the bandwidth of each of the six channels may correspond to 2.16 GHz. In addition, when bandwidth bonding is applied, up to four unit bandwidths can be bonded to support bandwidths up to 8.64 GHz.

[0131] In the present disclosure, the mmWave frequency band is described as including the 60 GHz frequency band, but the mmWave frequency band is not limited to the 60 GHz frequency band.

[0132] The first (operating) frequency band and the second (operating) band described in the present disclosure correspond to frequency bands at different frequency locations. For example, one of the first frequency band and the second frequency band may correspond to a mmWave frequency band and the other may correspond to a sub-7 GHz frequency band.

[0133] The present disclosure assumes that a STA can operate in both the first and second frequency bands. The corresponding STA may have the capability to simultaneously perform PPDU / frame transmission or reception in the first and second frequency bands (e.g., multi-band operation or multi-link operation (MLO) capability), or may have the capability to perform PPDU / frame transmission or reception in only one of the first or second frequency bands during a time interval.

[0134] In existing WLAN systems, it is assumed that STAs operate on a single frequency band. They can obtain channel information (e.g., primary channel location, bandwidth, etc.) of the corresponding AP through an AP scanning process and associate with the corresponding AP through the primary channel. The bandwidth of PPDUs transmitted or received by the STA must essentially include the primary channel. Furthermore, even for STAs capable of operating on multiple links within a single frequency band, the STA can associate with multiple links within the same frequency band and obtain channel information for each link through scanning, etc.

[0135] As described above, when introducing a STA that supports operation in multiple frequency bands, assuming that its operation is similar to that defined in existing WLAN systems, the STA can obtain channel information about the corresponding frequency bands by performing separate processing such as scanning in each of the first and second frequency bands. In this case, delays may be caused when switching operating frequency bands, and since channels must be allocated to STAs by including a predetermined primary channel, resource utilization flexibility may be reduced.

[0136] The present disclosure describes various examples of the present disclosure below, which are for providing information about a channel in a first frequency band to a STA on a second frequency band for PPDU / frame transmission or reception in the first frequency band.

[0137] Figure 9 is a flowchart for explaining an example of a method for transmitting channel information about an operating frequency band according to the present disclosure.

[0138] In S910 , a first STA may send a first frame to a second STA on a second frequency band, where the first frame includes first information about a specific channel in the first frequency band and / or second information about channel allocation in the first frequency band.

[0139] In other words, the first frame may include the first information but not the second information, or may include the second information but not the first information, or may include both the first information and the second information.

[0140] The specific channel indicated by the first information may be named as a primary-like channel, but the scope of the present disclosure is not limited to this name and another name may be used. A specific channel may be defined as a channel for sending / receiving control frames and / or management frames. Additionally or alternatively, a specific channel may correspond to a non-punctured channel. For example, a specific channel may be the same as or different from the primary channel of the BSS. When the specific channel is different from the primary channel of the BSS, some / all of the auxiliary channels of the BSS may be used / allocated as specific channels.

[0141] There may be multiple frequency units in the first frequency band. Figure 8 In the example shown in FIG, channels 1 to 6 with a size of 2.16 GHz may correspond to six frequency units. The multiple frequency units may or may not overlap with each other. The sizes of the multiple frequency units may be the same or different. One of the multiple frequency units may be allocated to a STA. Alternatively, some or all of the multiple frequency units may be allocated to a STA.

[0142] Multiple frequency units can be mapped to multiple specific channels, respectively. For example, one frequency unit can include one specific channel. One of the multiple specific channels can be allocated to a STA. Alternatively, some / all of the multiple specific channels can be allocated to a STA.

[0143] The channel allocation associated with the second information may be indicated in various ways, such as a channel index, a number of channels, or a bitmap. Based on or in association with the channel allocation indicated by the second information, a channel corresponding to an available PPDU bandwidth (or an allowed PPDU bandwidth or a maximum transmission width corresponding thereto) may be allocated to the STA. The available PPDU bandwidth may be any one of a plurality of PPDU bandwidths. The available PPDU bandwidth may be, for example, the maximum PPDU bandwidth among the plurality of PPDU bandwidths. Alternatively, when there are multiple available PPDU bandwidths, a channel corresponding to each PPDU bandwidth may be allocated to the STA.

[0144] Switching from the second frequency band to the first frequency band may be performed based on the first frame transmitted / received on the second frequency band. Alternatively, for a STA supporting multi-band (or multi-link) operation, frame transmission or reception on the second frequency band as well as frame transmission or reception on the first frequency band may be supported without performing frequency band switching. For example, in addition to frame transmission or reception on the second frequency band, frame transmission or reception may also be performed on the first frequency band.

[0145] In S920 , the first STA may perform second frame transmission / reception with the second STA on the first frequency band based on the first information and / or the second information.

[0146] BSS association of the second STA on the first frequency band is not necessarily required. In other words, the second STA can transmit or receive data frames only on the allocated channel on the first frequency band without associating with the AP STA on the first frequency band. Additionally or alternatively, even without association, the second STA can transmit or receive some management / control frames on the allocated channel on the first frequency band.

[0147] A channel through which the second frame is transmitted / received on the first frequency band may be included in the channels indicated by the second information of the first frame.

[0148] When the first information of the first frame indicates a specific channel on the first frequency band, the control / management frame may be transmitted or received on the corresponding specific channel. When the first frame does not include the first information, or when the specific channel does not exist on the first frequency band, the control / management frame may be transmitted or received on the specific channel or the primary channel of the second frequency band.

[0149] Information about the bandwidth of the first PPDU including the second frame transmitted / received on the first frequency band may be included in the SIG field of the corresponding first PPDU, or may be included in another PPDU transmitted / received on the first frequency band or the second frequency band before the corresponding first PPDU is transmitted or received.

[0150] For example, information about the bandwidth of a first PPDU transmitted or received on a first frequency band may be included in a second PPDU (or a data field of the second PPDU) transmitted or received on the first frequency band. The second PPDU may be transmitted or received on a specific channel existing in the first frequency band, or may be transmitted and received on a channel on the first frequency band in which the first PPDU is to be transmitted or received.

[0151] Alternatively, information about the bandwidth of the first PPDU transmitted or received on the first frequency band may be included in a third PPDU (or a data field of the third PPDU) transmitted or received in the second frequency band.

[0152] although Figure 9 Although not shown in FIG, after switching from the second frequency band to the first frequency band based on the first frame transmitted or received on the second frequency band in S910, switching to the second frequency band may be performed again. In this case, channel information in the second frequency band may be provided to the second STA.

[0153] For example, the third frame including channel information (eg, specific channel information and / or channel allocation information) in the second frequency band may include an indication of whether specific channels and / or channel allocations in the second frequency band performing S910 are (re)used in the same manner.

[0154] Alternatively, the channel information in the second frequency band included in the third frame may include information (e.g., third information) indicating a specific channel that is independent of (i.e., may be the same as or different from) the specific channel in the second frequency band in which S910 is performed. The channel information in the second frequency band included in the third frame may include information (e.g., fourth information) indicating a channel allocation that is independent of (i.e., may be the same as or different from) the channel allocation in the second frequency band in which S910 is performed.

[0155] Therefore, frame (eg, fourth frame) transmission or reception between the first STA and the second STA may be performed in the second frequency band.

[0156] Figure 9 The method described in the example can be used by Figure 1 The first device (100) in is executed. For example, Figure 1At least one processor (102) of the first device (100) may be configured to send a frame including channel information in a frequency band other than the current operating frequency band to the second device (200), and based on this, perform frame exchange with the second device (200) on another frequency band. In addition, at least one memory (104) of the first device (100) may store instructions for executing the operation of the second device (200) when executed by the at least one processor (102). Figure 9 Examples or instructions of the methods described in the examples described below.

[0157] Figure 10 is a flowchart for explaining an example of a method for receiving channel information about an operating frequency band according to the present disclosure.

[0158] In S1010 , a second STA may receive a first frame from a first STA on a second frequency band, the first frame including first information about a specific channel in the first frequency band and / or second information about channel allocation in the first frequency band.

[0159] In S920 , the first STA may perform second frame transmission / reception with the first STA on the first frequency band based on the first information and / or the second information.

[0160] Due to the specific details of the first and second frequency bands, the specific channels / channel allocations of each frequency band, and the operation and reference Figure 9 The descriptions are the same, so repeated descriptions are omitted.

[0161] Figure 10 The method described in the example can be used by Figure 1 The second device (200) in is executed. For example, Figure 1 The at least one processor (202) of the second device (200) may be configured to receive a frame including channel information in a frequency band other than the current operating frequency band from the first device (100), and based on this, perform frame exchange with the first device (100) on another frequency band. In addition, the at least one memory (204) of the second device (200) may store instructions for executing the operation of the at least one processor (202) in the second device (200). Figure 10 Examples or instructions of the methods described in the examples described below.

[0162] Figure 9 and Figure 10 Examples of may correspond to some of the various examples of the present disclosure. In the following, the present disclosure is described in more detail including Figure 9 and Figure 10 Various examples of examples.

[0163] In the embodiments described below, the sub-7 GHz band and the 60 GHz band are described as representative examples of operating bands to which the present disclosure is applied, but the embodiments described below may also be similarly applied to another mmWave band other than 60 GHz or an operating band other than the mmWave band or the sub-7 GHz band.

[0164] In the embodiments described below, information for allocating a channel in another frequency band to an STA in a specific frequency band may be referred to as an improved subchannel selective transmission (SST) element. Although the existing SST element includes information about channel allocation in the same frequency band, the improved SST element according to the present disclosure is different in that it includes information about a specific channel and / or channel allocation in another frequency band. In the following examples, descriptions are made using names such as improved SST element, 60GHz SST element, sub-7GHz SST element, etc., but the scope of the present disclosure is not limited to such names and includes an element / frame with another name that includes information about a specific channel and / or channel allocation in another frequency band.

[0165] Implementation Method 1

[0166] For STAs operating in the sub-7 GHz band, a 60 GHz SST element may be sent in the sub-7 GHz band, including information allocating a channel corresponding to the PPDU bandwidth to be transmitted or received in the 60 GHz band. For example, the 60 GHz SST element may indicate to the STA the channel corresponding to the maximum possible PPDU bandwidth in the 60 GHz band.

[0167] Additionally or alternatively, for STAs operating in the sub-7 GHz band, a 60 GHz SST element including information indicating a similar primary channel in the 60 GHz band may be transmitted in the sub-7 GHz band. The similar primary channel may correspond to a channel for transmitting or receiving control / management frames, etc., and is described in detail in Embodiment 2.

[0168] Additionally or alternatively, for a STA operating in a band below 7 GHz, a 60 GHz SST element may be transmitted in the band below 7 GHz, the element including information allocating a channel corresponding to a PPDU bandwidth to be transmitted or received in the 60 GHz band, and information indicating a similar primary channel in the 60 GHz band.

[0169] The bandwidth of a PPDU in the 60 GHz band may vary for each transmission. Therefore, it is necessary to indicate the bandwidth of the PPDU, and various methods can be applied to achieve this. For example, information indicating the bandwidth of the corresponding PPDU can be included in at least one SIG field of the PHY preamble of the PPDU. Alternatively, the bandwidth of the corresponding PPDU can be indicated by a specific frame before the PPDU is transmitted or received. For example, information indicating the bandwidth of a PPDU to be transmitted or received in the 60 GHz band can be indicated by a specific frame transmitted or received in the 60 GHz band. Alternatively, information indicating the bandwidth of a PPDU to be transmitted or received in the 60 GHz band can be indicated by a specific frame transmitted or received in a frequency band lower than 7 GHz.

[0170] The PPDU including the specific frame (i.e., the frame including the PPDU bandwidth information) can be transmitted on the primary channel or a similar primary channel. For example, a specific frame at 60 GHz can be transmitted or received on a similar primary channel. For example, a specific frame at a frequency band below 7 GHz can be transmitted or received on the primary channel.

[0171] Alternatively, a specific frame may be transmitted on a channel where a corresponding PPDU (i.e., a PPDU whose bandwidth information is indicated by a specific frame) will be transmitted or received. In other words, a specific frame including information about the bandwidth of the corresponding PPDU may be transmitted within the bandwidth of a PPDU to be transmitted or received after the specific frame.

[0172] Implementation Method 2

[0173] A similar primary channel may be defined / used as a channel for transmitting or receiving control / management frames, etc. in the 60 GHz frequency band.

[0174] For example, when the bandwidth defined in the existing sub-7 GHz band is used as it is used in the 60 GHz band, the bandwidth of a primary channel may be defined as 20 MHz, or may be defined as a different size such as 40 MHz, 80 MHz, etc.

[0175] Alternatively, the channels in the 60 GHz band may have an upward locking relationship compared to the channels in the existing sub-7 GHz band. For example, N upward locking may be applied to the PPDU bandwidths of 20 / 40 / 80 / 160 / 320 MHz defined in the sub-7 GHz band to define PPDU bands of N*20 / N*40 / N*80 / N*160 / N*320 MHz in the 60 GHz band. In this case, the bandwidth of the similar primary channel may be defined as N*20 MHz corresponding to (20 MHz in the sub-7 GHz band). For example, when an upward locking of N=4 is applied, a similar primary channel of 80 MHz may be defined, and when an upward locking of N=10 is applied, a similar primary channel of 200 MHz may be defined.

[0176] When a quasi-primary channel is defined by a STA, the 60 GHz frequency band may be divided into multiple parts (or multiple frequency units), and a quasi-primary channel may be defined for each part. The STA that defines the quasi-primary channel may be an AP STA.

[0177] For example, each part may be divided based on the maximum bandwidth unit that can be used for PPDU transmission or reception in the 60 GHz band. Figure 8 In the example shown, each segment can be a 2.16 GHz channel corresponding to channels 1 through 6, and a primary channel-like channel can be defined for each of channels 1 through 6. This is merely an example, and the frequency location and / or size of each segment is not limited. For example, some or all of the segments may or may not overlap. For example, some or all of the segments may have the same size or different sizes.

[0178] Alternatively, a specific channel may be defined as a quasi-primary channel, multiple specific channels may be defined as one quasi-primary channel, or multiple specific channels may be defined as multiple quasi-primary channels without being divided into sections (i.e., independent of the sections). For example, when multiple quasi-primary channels are defined, one of these quasi-primary channels may be allocated to each STA.

[0179] When transmitting or receiving a PPDU, a primary-like channel may not be punctured. Therefore, a STA assigned a primary-like channel can reduce power consumption by performing decoding only on channels that include the primary-like channel. For example, if a STA is assigned a channel wider than the size of a primary-like channel in the 60 GHz band, even if a specific signal / energy is detected within the assigned channel (on a (secondary) channel other than the primary-like channel), it may not be able to decode the corresponding signal if the specific signal / energy is not detected on the primary-like channel.

[0180] Implementation 3

[0181] This embodiment relates to a method for signaling channel information about another frequency band based on a multi-band operation capability or configuration (e.g., transmission and reception operations in a sub-7 GHz band and a 60 GHz band in the same time interval). In addition, this embodiment may correspond to a method for signaling channel information about another frequency band based on a multi-link operation capability or configuration (e.g., operations when transmission or reception operations are supported on multiple links in the same time interval and one link is in a sub-7 GHz band and another link is in a 60 GHz band).

[0182] When operating simultaneously in the sub-7 GHz band and the 60 GHz band based on multi-band operation or multi-link operation (i.e., when PPDU transmission or reception can be performed in both bands), control / management frames carrying information for PPDU transmission and reception can be transmitted or received not only in the sub-7 GHz band but also in the sub-70 GHz band. Control / management frames carrying information for PPDU transmission or reception in the 60 GHz band can be transmitted and received. In this case, operation in the 60 GHz band can be performed based on information on channel allocation to be used for PPDU transmission or reception in the 60 GHz band (in addition, information on the 60 GHz PPDU bandwidth), without defining and indicating a similar primary channel for the 60 GHz band.

[0183] Additionally or alternatively, primary channel-like indication information about the 60 GHz band, PPDU bandwidth information, frequency location (e.g., center frequency) information, etc. may be indicated via a control / management frame carrying information regarding operations on the 60 GHz band transmitted or received in a sub-7 GHz band.

[0184] Additionally or alternatively, control / management frames carrying information for operations in the 60 GHz band can be defined as being transmitted or received in the 60 GHz band. In other words, to account for increased latency, implementation complexity, and other factors, cross-band operation can be defined as not supported, and control / management frames and data frames can be transmitted or received within the same band. In this case, similar primary channel information and channel allocation information for the 60 GHz band are required. Defining and allocating similar primary channels can reduce power consumption and other benefits during STA operations in the 60 GHz band.

[0185] Implementation 4

[0186] This embodiment relates to a method for signaling channel information about another frequency band based on a single-band operation capability or configuration (e.g., transmission and reception operations on a frequency band below 7 GHz and a frequency band below 60 GHz within the same time interval). Furthermore, this embodiment may also correspond to a method for signaling channel information on another frequency band based on a limited multi-link operation capability or configuration (e.g., when transmission or reception operations on multiple links (some of which are in a frequency band below 7 GHz and others in a frequency band below 60 GHz) are supported, but transmission or reception operations on only one link are supported within the same time interval).

[0187] In this case, for STAs operating in the lower than 7 GHz band, a 60 GHz SST element including information for operating in the 60 GHz band may be transmitted in the lower than 7 GHz band. Examples of information included in the 60 GHz SST element may be applied to the contents described in the above embodiments.

[0188] For STAs operating in the 60 GHz band, a Sub-7 GHz SST element including information for operation in the Sub-7 GHz band may be transmitted in the 60 GHz band. The Sub-7 GHz SST element may be transmitted in the 60 GHz band, for example, for band switching (or reallocation) from the 60 GHz band to the Sub-7 GHz band after performing a band switch from the Sub-7 GHz band to the 60 GHz band. For example, a frame including the Sub-7 GHz SST element may be transmitted on a similar primary channel defined for the 60 GHz band.

[0189] For a STA that previously operated in the lower-than-7 GHz frequency band, the lower-than-7 GHz SST element may include information (eg, 1-bit information) indicating whether to reuse the previously operated link / channel.

[0190] Additionally or alternatively, the Below 7 GHz SST element may include information about a primary channel in the Below 7 GHz band and / or information about channel allocation (or bandwidth allocation). For example, for a STA that previously operated in the Below 7 GHz band, the Below 7 GHz SST element may include information indicating the primary channel of the previously operated link and / or the BSS bandwidth allocation of the previously operated link. For example, even for a STA that previously operated in the Below 7 GHz band, the Below 7 GHz SST element may include information indicating the primary channel of a link that is independent of (or different from) the previously operated link and / or information indicating the BSS bandwidth allocation of the previously operated link.

[0191] According to the new operation of providing channel information for a specific frequency band to STAs on different frequency bands, which is not defined in the existing WLAN system, new effects such as reducing delays in switching operating frequency bands and improving flexibility in channel allocation can be achieved.

[0192] The above-mentioned embodiments combine the elements and features of the present disclosure in a predetermined form. Unless otherwise explicitly mentioned, each element or feature should be considered as optional. Each element or feature can be implemented in a form not combined with other elements or features. In addition, the embodiments of the present disclosure may include some elements and / or features of the combination. The order of the operations described in the embodiments of the present disclosure may be changed. Some elements or features of an embodiment may be included in other embodiments, or may be replaced by corresponding elements or features of other embodiments. Obviously, an embodiment may include claims that do not have a clear reference relationship in the combined claims, or may be included as new claims through modification after application.

[0193] It is clear to those skilled in the relevant art that the present disclosure may be implemented in other specific forms within the scope of the essential features of the present disclosure. Therefore, the above detailed description should not be interpreted restrictively in every aspect, but should be considered as illustrative. The scope of the present disclosure should be determined by a reasonable interpretation of the appended claims, and all variations within the scope of equivalents of the present disclosure are included within the scope of the present disclosure.

[0194] The scope of the present disclosure includes software or machine executable commands (e.g., operating systems, applications, firmware, programs, etc.) that perform operations in accordance with the methods of various embodiments in a device or computer, and non-transitory computer-readable media that enable software or commands, etc. to be stored and executable in a device or computer. Commands that can be used to program a processing system that performs the features described in this disclosure can be stored in a storage medium or a computer-readable storage medium, and the features described in this disclosure can be implemented by using a computer program product that includes such a storage medium. The storage medium may include high-speed random access memory, such as, but not limited to, DRAM, SRAM, DDR RAM, or other random access solid-state storage devices, and it may include non-volatile memory, such as, for example, one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid-state storage devices. The memory optionally includes one or more storage devices located away from the processor. The memory, or alternatively, the non-volatile memory device in the memory includes a non-transitory computer-readable storage medium. The features described in this disclosure may be stored in any machine-readable medium to control the hardware of a processing system and may be integrated into software and / or firmware that allows the processing system to utilize the results from the embodiments of this disclosure and interact with other mechanisms. Such software or firmware may include, but is not limited to, application code, device drivers, operating systems, and execution environments / containers.

[0195] Industrial Applicability

[0196] The method proposed in the present disclosure is mainly described based on an example of application to a system based on IEEE 802.11 (5G system), but can be applied to various WLAN or wireless communication systems other than the IEEE 802.11-based system.

Claims

1. A method performed by a first station STA in a wireless local area network WLAN system, the method comprising the following steps: sending a first frame to a second STA on a second frequency band, the first frame including at least one of first information about a specific channel in the first frequency band or second information about channel allocation in the first frequency band; as well as Based on at least one of the first information or the second information, transmission or reception of a second frame is performed with the second STA on the first frequency band.

2. The method according to claim 1, wherein: The specific channel corresponds to at least one of a primary-like channel, a non-punctured channel, a channel that transmits or receives a control frame, or a channel that transmits or receives a management frame.

3. The method according to claim 1, wherein: There are a plurality of frequency units on the first frequency band, the specific channel corresponds to one of the plurality of specific channels, and each of the plurality of specific channels is mapped to one frequency unit.

4. The method according to claim 3, wherein: The plurality of frequency units overlap with each other or do not overlap with each other.

5. The method according to claim 1, wherein: The second information includes information about at least one channel corresponding to at least one available PPDU bandwidth.

6. The method according to claim 1, wherein: information about a bandwidth of a first physical layer protocol data unit PPDU comprising the second frame transmitted or received on the first frequency band: is included in a signal SIG field of the first PPDU, is included in a second PPDU transmitted or received on the first frequency band before the transmission or reception of the first PPDU, or is included in a third PPDU transmitted or received on the second frequency band before the transmitting or the receiving of the first PPDU.

7. The method according to claim 6, wherein: The second PPDU is transmitted or received on the specific channel in the first frequency band, or is transmitted or received on a channel in the first frequency band where the first PPDU is to be transmitted or received.

8. The method according to claim 1, wherein: After performing switching from the second frequency band to the first frequency band based on the first frame, a third frame including information related to switching from the first frequency band to the second frequency band is provided to the second STA.

9. The method according to claim 8, wherein: The third frame includes information indicating whether a specific channel and a channel allocation identical to the specific channel are used and the channel allocation in the second frequency band in which the first frame is transmitted.

10. The method according to claim 8, wherein: based on the third frame including at least one of third information indicating a specific channel independent of a specific channel in the second frequency band in which the first frame is transmitted or fourth information indicating a channel allocation independent of a channel allocation in the second frequency band in which the first frame is transmitted, Based on at least one of the third information or the fourth information, transmission or reception of a fourth frame between the first STA and the second STA is performed on the second frequency band.

11. The method according to claim 1, wherein: The first frequency band is a millimeter wave (mmWave) frequency band, and the second frequency band is a sub-7 GHz frequency band, or The first frequency band is the sub-7 GHz frequency band, and the second frequency band is the mmWave frequency band.

12. A first station STA device in a wireless local area network (WLAN) system, the device comprising: at least one transceiver; as well as at least one processor connected to the at least one transceiver, Wherein, the at least one processor is configured to: transmitting, by the at least one transceiver, a first frame to a second STA on a second frequency band, the first frame including at least one of first information about a specific channel in the first frequency band or second information about channel allocation in the first frequency band; and Based on at least one of the first information or the second information, a second frame is transmitted or received with the second STA on the first frequency band through the at least one transceiver.

13. A method performed by a second station (STA) in a wireless local area network (WLAN) system, the method comprising the following steps: receiving a first frame from a first STA on a second frequency band, the first frame including at least one of first information about a specific channel in the first frequency band or second information about channel allocation in the first frequency band; as well as Based on at least one of the first information or the second information, transmission or reception of a second frame is performed with the first STA on the first frequency band.

14. A second station STA device in a wireless local area network (WLAN) system, the device comprising: at least one transceiver; as well as at least one processor connected to the at least one transceiver, Wherein, the at least one processor is configured to: receiving, by the at least one transceiver, a first frame from a first STA on a second frequency band, the first frame including at least one of first information about a specific channel in the first frequency band or second information about channel allocation in the first frequency band; and Based on at least one of the first information or the second information, transmission or reception of a second frame is performed with the first STA on the first frequency band through the at least one transceiver.

15. A processing device configured to control a station STA in a wireless local area network (WLAN) system, the processing device comprising: at least one processor; as well as At least one computer memory operatively connected to the at least one processor, the at least one computer memory storing instructions for performing the method according to any one of claims 1 to 11 upon execution by the at least one processor.

16. At least one non-transitory computer-readable medium storing at least one instruction, wherein: The at least one instruction is executed by at least one processor to control a device to execute the method according to any one of claims 1 to 11 in a wireless local area network (WLAN) system.

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