Method and apparatus for performing communication based on beamforming in wireless LAN system

Abstract

Disclosed are an operation method and apparatus in a wireless LAN system. A method performed by a first station (STA) in a wireless LAN system according to one embodiment of the present disclosure comprises the steps of: transmitting a beamforming feedback matrix to a second STA in a first frequency band; receiving beamforming-related information including first information related to a specific beam from the second STA; and performing communication with the second STA based on beamforming-related information within the second frequency band, in which the first information is configured based on a beamforming feedback matrix, and the beamforming-related information may include second information related to antenna settings of the first frequency band.

Description

Technical Field

[0001] The present disclosure relates to communication operations in a wireless local area network (WLAN) system, and more particularly, to a method and apparatus for performing communication based on beamforming. 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 are being studied to support increased bandwidth, efficient utilization of multiple frequency bands, and increased spatial streams. In particular, various technologies are being studied to support low-latency or real-time traffic. Furthermore, new technologies are being discussed to support Ultra-High Reliability (UHR), including improvements or extensions 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 performing communication based on beamforming in a wireless LAN system.

[0006] The technical problem of the present disclosure is to provide a method and apparatus for transmitting and receiving configuration information related to beamforming at less than 7 GHz for beamforming at 60 GHz.

[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 embodiment of the present disclosure, a method performed by a first station (STA) in a wireless LAN system may include: sending a beamforming feedback matrix to a second STA within a first frequency band; receiving beamforming-related information including first information related to a specific beam from the second STA; and communicating with the second STA based on the beamforming-related information within a second frequency band, where the first information may be configured based on the beamforming feedback matrix, and the beamforming-related information may include second information related to an antenna setting for the first frequency band.

[0010] According to another embodiment of the present disclosure, a method performed by a second station (STA) in a wireless LAN system may include: receiving a beamforming feedback matrix from a first STA within a first frequency band; sending beamforming-related information including first information related to a specific beam to the first STA; and performing communication with the first STA based on the beamforming-related information within the second frequency band, and the first information may be configured based on the beamforming feedback matrix, and the beamforming-related information may include second information related to an antenna setting for the first frequency band.

[0011] Technical Effects

[0012] According to various embodiments of the present disclosure, a method and apparatus for performing communication based on beamforming in a wireless LAN system may be provided.

[0013] According to various embodiments of the present disclosure, a method and apparatus for transmitting and receiving configuration information related to beamforming at less than 7 GHz for beamforming at 60 GHz may be provided.

[0014] According to various embodiments of the present disclosure, overhead associated with beam training / tracking for signal transmission and reception at 60 GHz may be reduced, and transmission efficiency may be improved.

[0015] According to various embodiments of the present disclosure, during signal transmission, output can be increased and delay can be reduced.

[0016] 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

[0017] 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.

[0018] Figure 1 A block diagram illustrating a configuration of a wireless communication device according to an embodiment of the present disclosure is illustrated.

[0019] Figure 2 is a diagram illustrating an exemplary structure of a WLAN system to which the present disclosure can be applied.

[0020] Figure 3 This is a diagram for explaining a link establishment process to which the present disclosure can be applied.

[0021] Figure 4 This is a diagram for explaining a backoff process to which the present disclosure can be applied.

[0022] Figure 5This is a diagram for explaining a frame transmission operation based on CSMA / CA to which the present disclosure can be applied.

[0023] 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.

[0024] 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.

[0025] Figure 8 and Figure 9 is a diagram for explaining an SLS process to which the present disclosure can be applied.

[0026] Figure 10 is a flowchart for explaining a method performed by a first STA according to an embodiment of the present disclosure.

[0027] Figure 11 is a flowchart for explaining a method performed by a second STA according to an embodiment of the present disclosure.

[0028] Figure 12 is a diagram for explaining an SLS process to which the present disclosure can be applied. DETAILED DESCRIPTION

[0029] 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.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] 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".

[0034] 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.

[0035] Hereinafter, technical features of examples to which the present disclosure can be applied will be described.

[0036] Figure 1 A block diagram of a wireless communication device according to an embodiment of the present disclosure is illustrated.

[0037] Figure 1The 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.

[0038] Figure 1 The 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.

[0039] 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 medium access control (MAC) layer and a physical layer (PHY) that conform to the IEEE 802.11 standard.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] Figure 2 is a diagram illustrating an exemplary structure of a wireless LAN system to which the present disclosure can be applied.

[0050] 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.

[0051] 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.

[0052] 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).

[0053] 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.

[0054] 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.

[0055] 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).

[0056] 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.

[0057] 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.

[0058] In addition to the above-mentioned structure of the DS, an extended service set (ESS) can also be configured to provide wide coverage.

[0059] 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.

[0060] 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.

[0061] Figure 3 is a diagram for explaining a link establishment process to which the present disclosure can be applied.

[0062] 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.

[0063] 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.

[0064] 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).

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] 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.

[0072] 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.

[0073] 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.

[0074] Figure 4 It is a diagram for explaining a backoff process to which the present disclosure can be applied.

[0075] 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.

[0076] 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).

[0077] 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, ...).

[0078] 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.

[0079] 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.

[0080] As in Figure 4 In the example of , a data frame is a frame for transmitting data forwarded to a higher layer, and may be transmitted after a backoff performed after a DIFS has elapsed since the medium became idle. In addition, a management frame is a frame for exchanging management information that is not forwarded to a higher layer, and is transmitted after a backoff is performed after an IFS such as a DIFS or a point coordination function IFS (PIFS). As subtype frames of the management frame, there are beacons, association request / responses, reassociation request / responses, probe request / responses, authentication request / responses, and the like. A control frame is a frame for controlling access to a medium. As subtype frames of the control frame, there are 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 trigger, and the like. If the control frame is not a response frame of the previous frame, it is transmitted after performing a backoff after DIFS, and if it is a response frame of the previous frame, it is transmitted without performing a backoff after a short IFS (SIFS). The type and subtype of the frame can be identified by the type field and subtype field in the frame control (FC) field.

[0081] 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.

[0082] Figure 5 is a diagram for explaining a frame transmission operation based on CSMA / CA to which the present disclosure can be applied.

[0083] 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.

[0084] 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.

[0085] 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.

[0086] 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.

[0087] 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.

[0088] 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.

[0089] 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.

[0090] 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.

[0091] 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.

[0092] 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.

[0093] 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.

[0094] 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.

[0095] 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.

[0096] 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.

[0097] 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.

[0098] 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.

[0099] 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).

[0100] 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.

[0101] 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)).

[0102] 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).

[0103] 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)).

[0104] 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 an HE PPDU or an EHT PPDU, which will be described later.

[0105] 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.

[0106] 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.

[0107] 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.

[0108] 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.

[0109] 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.

[0110] 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.

[0111] 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.

[0112] 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.

[0113] 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.

[0114] 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.

[0115] 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.

[0116] 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.).

[0117] 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.

[0118] 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.

[0119] 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.

[0120] 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.).

[0121] 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.

[0122] 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.

[0123] 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.

[0124] 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.

[0125] 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.

[0126] 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.

[0127] 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.

[0128] 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.

[0129] 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.

[0130] Sector Level Scan (SLS) phase

[0131] The SLS phase may include up to four components: an initiator sector sweep (ISS) for training the initiator link, a responder sector sweep (RSS) for training the responder link, a sector sweep (SSW) feedback process, and an SSW acknowledgment (ack) process.

[0132] The initiator may start the SLS phase by sending an ISS frame. Except when an ISS occurs during a beacon transmission interval (BTI), the responder may not start RSS frame transmission until the ISS has successfully completed.

[0133] Except when RSS occurs in A-BFT, the initiator may not start the SSW feedback process before the RSS phase is successfully completed. The responder may not start the initiator and SSW confirmation process of A-BFT. The responder may start the initiator and SSW response process immediately after the initiator and SSW feedback process are successfully completed.

[0134] The only BF frames that the initiator can send during the SLS phase may be DMG beacon frames, SSW frames, and SSW-feedback frames. The only BF frames that the responder can send during the SLS phase may be SSW frames and SSW-acknowledgement frames.

[0135] If the initiator uses SSW frames to perform ISS, the responder can use SSW frames to perform RSS. If the initiator uses short SSW PPDUs to perform ISS, the responder can use short SSW PPDUs to perform RSS.

[0136] A STA may not send a short SSW PPDU to any STA other than an EDMG STA. For each long beamforming interframe space (LBIFS) included as part of sector scanning, a STA that performs ISS or RSS using a short SSW PPDU may increase the CDOWN field value in the short SSW PPDU by 2.

[0137] An EDMG STA that supports receiving a Short SSW PPDU from an unassociated STA during CBAP allocation may set the RX Unassociated Short SSW subfield of the SSW field to 1 within the transmitted DMG beacon frame.

[0138] If the initiator and responder each perform TXSS during SLS, then both the initiator and responder can have their own transmit sectors at the end of the SLS phase. If ISS or RSS uses receive sector scanning, then the responder or initiator can each have its own receive sector.

[0139] The following rules may apply to all channel access in a directional multi-gigabit (DMG) BSS. A STA may not transmit a frame as part of a sector sweep consisting of at least two sectors if a response from the STA identified in the RA field of the transmitted frame is expected within SIFS. A STA may not change its transmit power during a sector sweep.

[0140] Except when used to implement radar functionality, the rules described below may apply to PPDUs sent as part of a sector scan.

[0141] - PPDUs sent by non-EDMG STAs as part of sector scan may not include the TRN field. For frames sent as part of sector scan, non-EDMG STAs may set the TRN-LEN parameter of TXVECTOR to 0.

[0142] - PPDUs sent by an EDMG STA as part of a sector scan and not including a DMG beacon may not include a TRN field. For frames sent as part of a sector scan and not including a DMG beacon, the EDMG STA may set the TRN-LEN parameter of the TXVECTOR to 0.

[0143] As an example of the present disclosure, Figure 8 As shown, the initiator can have many sectors, the responder can have only one transmit sector, and the receive sector sweep can be used in the responder sector sweep. The responder can send all responder SSW frames through the same transmit sector, and the initiator can switch the receive antenna at the same time.

[0144] As an example of the present disclosure, Figure 9 As shown, the initiator may have many transmission sectors, and the responder may have one transmission sector. In this case, reception learning for the initiator may be performed during the BRP phase.

[0145] Beam refinement protocol (BFP) phase

[0146] BRP is the process by which a STA trains the RX and TX antenna arrays and uses an iterative process to improve the TX antenna configuration and RX antenna configuration. BRP can be used regardless of the antenna configuration supported by the STA.

[0147] The BRP phase may include a BRP setup subphase, a multi-sector ID detection (MID) subphase, a beam combining (BC) subphase, a subset of the previous subphases, and one or more beam refinement transactions.

[0148] BRP setup allows STAs to exchange beam refinement capability information and request execution of other BRP sub-phases.

[0149] Due to the imperfect quasi-omnidirectional receive antenna pattern, MID and BC (collectively referred to as the MIDC sub-phase) can optionally be used to find a better initial antenna weight vector (AWV) than the initial AWV that can be found in SLS for iterative beam refinement. In MID, the quasi-omnidirectional transmit pattern can be tested for a large number of receive AWVs. This can reverse the search role of the transmit sector scan. In BC, a small set of transmit and receive AWVs is tested in paired combinations, thus avoiding the use of quasi-omnidirectional patterns. Finally, given a starting point for SLS or MIDC, the STA can use a request / response frame exchange called a beam refinement transaction to explore a larger set of transmit and receive AWVs.

[0150] A beam refinement transaction is a set of BRP frames consisting of a beam refinement request and a response. The beam refinement request can be at least one of a transmit beam refinement request or a receive beam refinement request.

[0151] A transmit beam congestion request (TX-TRN-REQ field in the BRP Request field is set to 1) can indicate the transmitting STA's need for transmit antenna array training. A BRP PPDU (or the next BRP PPDU for that STA) with TX-TRN-REQ set to 1 can be supplemented with a Transmit Training (TRN-T) subfield. STAs responding to a BRP PPDU can include feedback based on measurements performed during reception of the BRP PPDU. The type of feedback can be determined by the FBCK-TYPE field in the DMG Beam Refinement element included in the BRP PPDU.

[0152] A receive beam refinement request (L-RX field in the BRP request field is greater than 0) may indicate the transmitting STA's need for receive antenna array training. The responding STA may respond with a BRP PPDU with a receive training (TRN-R) subfield.

[0153] The request and response can be combined in the same frame. For example, the same frame can be used to transmit at least one of a beam refinement request or a receive beam refinement request. The same frame can also be used to receive both a beam refinement response and a beam refinement request.

[0154] The beam refinement response may be separated from the previous beam refinement request by at least SIFS and at most BRPIFS, which provides sufficient time to complete the transmission of that frame within a non-TDD SP or TXOP allocation.

[0155] If beam refinement occurs within the same allocation as SLS, the SLS initiator can become the beam refinement initiator. If beam refinement occurs in a separate allocation, the STA that sends the first beam refinement request can become the beam refinement initiator, and other STAs can become beam refinement responders.

[0156] Method for transmitting and receiving beamforming setting information below 7 GHz

[0157] In next-generation wireless LAN systems, the 60 GHz frequency band can be used for transmission and reception operations to support high throughput and low latency. However, due to the high frequency range of 60 GHz, if omnidirectional transmission is considered, the radio signal may experience severe path loss and signal attenuation, making smooth transmission and reception impossible.

[0158] Therefore, for efficient signal transmission and reception, beamforming can be used to perform directional transmission through a specific set of narrow beams.

[0159] As described above, in order to set a narrow beam for signal transmission and reception at 60 GHz, a complex process (eg, SLS process and / or BWP process, etc.) must be performed to find suitable beams for all directions. The above process has a problem of potentially high complexity.

[0160] Hereinafter, a method of transmitting and receiving beamforming setting information below 7 GHz is described to simplify a process for setting a narrow beam during beamforming for efficient signal transmission and reception at 60 GHz.

[0161] Figure 10 is a flowchart illustrating a method for a first STA to perform communication according to one embodiment of the present disclosure.

[0162] exist Figure 10 and Figure 11 In the embodiment, the first STA may be a non-AP STA as a beamformed party, and the second STA may be an AP as a beamformer. However, this is only one embodiment, and each of the first STA and the second STA may be implemented as a non-AP or an AP.

[0163] A first STA may transmit a beamforming feedback matrix to a second STA within a first frequency band ( S1010 ).

[0164] Specifically, a first STA may perform a sounding procedure with a second STA in a first frequency band (e.g., below 7 GHz). As an example, the first STA may perform a sounding measurement operation based on an NDP received from the second STA. As a result of the sounding measurement operation, the first STA may obtain compressed feedback information (e.g., a feedback matrix) and / or a beamforming feedback matrix. The first STA may transmit the result of the sounding measurement operation to the second STA.

[0165] The first STA may receive beamforming-related information including first information related to a specific beam from the second STA ( S1020 ).

[0166] Specifically, the first information related to a specific beam (ie, a main beam) may be configured / generated / determined based on the beamforming feedback matrix reported by the first STA to the second STA.

[0167] For example, the psi(ψ) and The angle information obtained by the beamforming feedback matrix is ​​generated / identified by the value. At least one of the direction, width, or range of a specific beam can be based on the angle information obtained by the beamforming feedback matrix.

[0168] As an example of the present disclosure, the beamforming-related information may include third information indicating the second frequency band and fourth information indicating a bandwidth of an available channel in the second frequency band indicated by the third information.

[0169] For example, the second frequency band may be indicated by the third information as one of 2.4 GHz, 5 GHz, 6 GHz, or 60 GHz. Furthermore, the bandwidth of the available channel may be configured as a bitmap indicating the bandwidth of the available channel in the second frequency band (indicated by the third information). Depending on the second frequency band, the bandwidth of the available channel may be indicated in units of 20 MHz or 2.16 GHz channels.

[0170] The beamforming-related information may include at least one of a change value of an angle obtained through a beamforming feedback matrix or time information when the beamforming feedback matrix is ​​measured.

[0171] In addition, the information related to beamforming may include second information related to the antenna configuration of the first frequency band. For example, the second information may include at least one of the following: information indicating whether the antenna pattern of the first frequency band and the antenna pattern of the second frequency band are the same, the number of transmit antennas and receive antennas of the first frequency band, or the power of the antennas of the first frequency band.

[0172] The first STA may perform communication with the second STA based on the beamforming-related information within the second frequency band ( S1030 ).

[0173] At least one of sector-level scanning (SLS) or beam refinement protocol (BRP) may be performed by the first STA and the second STA based on at least one of a direction, a width, or a range for a specific beam within the second frequency band.

[0174] For example, the first STA may perform SLS for a specific sector corresponding to at least one of a direction, a width, or a range for a specific beam within the second frequency band.

[0175] That is, the first STA may perform beamforming in the second frequency band using information related to beamforming in the first frequency band, and the first STA may perform communication with the second STA based on the beamforming performance result.

[0176] As another example of the present disclosure, the first STA may determine whether to perform beamforming based on information related to beamforming within the second frequency band, based on an elapsed time based on time information of measuring a beamforming feedback matrix.

[0177] For example, if the time elapsed based on the time information of the measured beamforming feedback matrix exceeds the alpha (α) value, the first STA may form a main beam through the existing beamforming training process without using the beamforming-related information. If the time elapsed based on the time information of the measured beamforming feedback matrix does not exceed the alpha value, the first STA may perform the beamforming process in the second frequency band using the beamforming-related information.

[0178] exist Figure 10 The method described in the example of the first STA can be performed by Figure 1 The first device (100) performs. For example, Figure 1 One or more processors (102) of a first device (100) may transmit a beamforming feedback matrix to a second STA via one or more transceivers (106) within a first frequency band. The one or more processors (102) may receive beamforming-related information including first information related to a specific beam from the second STA via one or more transceivers (106). The one or more processors (102) may communicate with the second STA based on the beamforming-related information within a second frequency band.

[0179] Additionally, the one or more memories (104) of the first device (100) may store instructions for executing the instructions when executed by the one or more processors (102). Figure 10 Instructions for the methods described in the examples.

[0180] Figure 11 is a flowchart illustrating a method for a second STA to perform communication according to one embodiment of the present disclosure.

[0181] The second STA may receive a beamforming feedback matrix from the first STA within the first frequency band ( S1110 ).

[0182] Specifically, the second STA may perform a sounding process with the first STA within the first frequency band.The second STA may send an NDP to the first STA and receive a sounding measurement result (eg, a beamforming feedback matrix) based on the NDP from the first STA.

[0183] The second STA may transmit beamforming-related information including first information related to a specific beam to the first STA ( S1120 ).

[0184] Already referenced Figure 10 An example of the beamforming-related information is described, and thus redundant description will be omitted.

[0185] The second STA may perform communication with the first STA based on the beamforming-related information within the second frequency band ( S1130 ).

[0186] That is, the second STA may perform a beamforming process in the second frequency band based on the beamforming-related information obtained in the first frequency band. For example, the second STA may perform an SLS process in a specific sector corresponding to the direction, width, and / or range of a specific beam included in the beamforming-related information. The second STA may communicate with the first STA based on the beamforming result.

[0187] exist Figure 11 The method described in the example of the second STA can be performed by Figure 1 The second device (200) is executed. For example, Figure 11 One or more processors (202) of a second device (200) may receive a beamforming feedback matrix from a first STA via one or more transceivers (206) within a first frequency band. The one or more processors (202) may transmit beamforming-related information including first information related to a specific beam to the first STA via one or more transceivers (206). The one or more processors (202) may communicate with the first STA based on the beamforming-related information within a second frequency band.

[0188] Additionally, the one or more memories (204) of the second device (200) may store instructions for executing the instructions when executed by the one or more processors (202). Figure 10 Instructions for the methods described in the examples.

[0189] Hereinafter, a transmission and reception method using beamforming is described to support high data rate transmission and high throughput in sub-7 GHz of the next generation wireless LAN system.

[0190] Implementation Method 1

[0191] To transmit and receive signals using beamforming, a beamformer (i.e., an AP) and a beamformee (i.e., a non-AP STA) may perform sounding to measure information about the channel between them. The beamformer may then obtain information about the angle used to perform beamforming and form a feedback matrix for guiding the beamforming.

[0192] For beamforming in sub-7 GHz, the beamformer can use the beamforming feedback matrix or compressed feedback matrix received from the beamformer to measure information about the angle used for beamforming. Here, information about the angle used for beamforming can be used for 60 GHz beam training.

[0193] As an example of the present disclosure, information on the angle for beamforming may be configured by psi (ψ) and psi (ψ) constituting a feedback matrix in the entire frequency band for signal transmission and reception. That is, the information on the angle used for beamforming can be configured as information on an average beam for beams used in beamforming.

[0194] The value of the above-mentioned angle can be configured as information for indicating the peak direction beam width of the main beam, and can be used as peak direction or beam width information.

[0195] As another example of the present disclosure, information about the angle used for beamforming may be composed of information about the minimum main beam and the maximum main beam obtained from the value of the minimum angle and the value of the maximum angle, and may be obtained by constituting the feedback matrix and To get the minimum and maximum angle values.

[0196] Here, information about each of the minimum angle and the maximum angle may be used to obtain a range of peak directions for the main beam or to construct a range of peak directions for the main beam.

[0197] In another example of the present disclosure, the feedback matrix may be constructed based on and The information about the angle for forming the main beam is measured based on the information about the angle obtained. The information about the angle for beamforming may include a peak direction and a beam width for the main beam based on the information about the angle for forming the main beam.

[0198] As another example of the present disclosure, the directivity for the main beam may be obtained using information about the angle obtained from the feedback matrix, and the information about the angle used for beamforming may indicate the directivity for the main beam.

[0199] When information about the angle of the main beam used for beamforming is obtained from beamforming feedback information below 7 GHz, the beamformer can transmit the information about the angle and / or information about the beamforming beam obtained from the information about the angle to the beamformer for transmitting and receiving signals by moving to 60 GHz.

[0200] The beamformer can use information about beams received via sub-7 GHz during beamforming training for transmitting and receiving 60 GHz signals to perform SLS and BRP for the direction of the main beam and / or directions within a specific range. This can reduce the complexity and time overhead of beamforming training.

[0201] As an example of the present disclosure, a beamformer that obtains information about a 60 GHz beam using information about a sub-7 GHz beamformed beam can perform SLS and BRP within the corresponding main beam width or beam range. Therefore, since the beamformer only performs beam training for a specific direction rather than an area in the entire direction, the time and process required for beam training can be simplified, and the complexity of determining the beam can be reduced.

[0202] Figure 10 FIG. 1 is a diagram for explaining a process in which an initiator and a responder perform an SLS process in a basic wireless LAN system. Figure 12 As shown, in a basic wireless LAN system, the initiator and the responder can perform SLS for Tx and Rx in all directions.

[0203] As an example of the present disclosure, in a next-generation wireless LAN system, sub-7 GHz beamforming feedback information can be used to estimate main beam information or the angle value for the main beam range. Then, when performing SLS in Tx and Rx, the main beam information or the angle value for the main beam range can be used to perform SLS for a portion or range of sectors rather than for all sectors. This reduces the overhead, complexity, and delay associated with performing SLS.

[0204] Additionally or alternatively, as an example of the present disclosure, the main beam information or the angle value for the main beam range estimated using sub-GHz beamforming feedback information may be applied only to the BRP process and not to the SLS process. In this case, the main beam information or the angle value for the main beam range may be used to more quickly find the beam sector.

[0205] Additionally or alternatively, information about the angle or main beam obtained using sub-7 GHz beamforming feedback information may be applied to both SLS and BRP or to only one of them.

[0206] Implementation Method 1-1

[0207] Since the antenna setting below 7 GHz is different from the antenna setting at 60 GHz, the beamformer may send information about the antenna setting below 7 GHz together with information about the beamformed beam to the beamformer to reduce errors in the main beam direction and width.

[0208] As an example of the present disclosure, information about the antenna configuration may include at least one of the following: information about the antenna pattern, the number of TX antennas, the number of RX antennas, information related to Tx power (i.e., Tx power used in beamforming), or a change value for the angle (of the main beam).

[0209] Here, the information on the antenna mode may indicate whether the same antenna mode as that below 7 GHz is used also at 60 GHz. For example, the information on the antenna mode (ie, the subfield in which the corresponding information is set) may consist of 1 bit.

[0210] For example, if the subfield value corresponding to the information on the antenna mode is set to 1, this may indicate whether the sub-7 GHz antenna mode is also used at 60 GHz.

[0211] As another example, if the subfield value corresponding to the information about the antenna pattern is set to 0, this may indicate that an antenna pattern different from the antenna pattern below 7 GHz is used at 60 GHz. In this case, the auxiliary beamforming information may not be used, and the auxiliary beamforming information may include information about the above-mentioned beamforming beams sent from the beamformer to the beamformer and / or antenna setting information.

[0212] Also, the variation value for the angle may be used to reduce the error for the main beam.The variation value for the angle may be defined and indicated as + / - angle increments.

[0213] In addition, in order to effectively use the information acquired below 7 GHz for beamforming training, the auxiliary beamforming information sent by the beamformer may include timing information of the measurement information.

[0214] For example, the information for 60 GHz beamforming may include time information for measuring the beamforming information. The time information may include information (eg, a timestamp, etc.) about the time when the beamformer receives the beamforming feedback matrix from the beamformer.

[0215] Based on the timestamp value, the beamformer performing 60 GHz operation may determine whether to use auxiliary beamforming information received from the beamformer via sub-7 GHz.

[0216] For example, in 60 GHz beamforming, if a certain value (e.g., an alpha value) has been exceeded based on the received timestamp value, the beamformer can perform a beamforming training process to form a primary beam without using the auxiliary beamforming information received from the beamformer. The beamformer can then perform beamforming using the formed primary beam. Here, the alpha value can be indicated by the AP to the STA via the 60 GHz band capability.

[0217] Implementation 1-2

[0218] To operate efficiently at 60 GHz, the beamformer can use the following procedures to send various information below 7 GHz. For example, the beamformer can use Selective Subchannel Transmission (SST), Extended Channel Switch Announcement (ECS), and Multi-Link Operation (MLO) to send various information below 7 GHz.

[0219] Implementation Method 1-2-1

[0220] As an example of the present disclosure, in a next-generation wireless LAN system, STAs operating at frequencies below 7 GHz can transmit and receive signals by moving to the 60 GHz band via SST. Therefore, information for 60 GHz beamforming can be transmitted via SST information transmitted at below 7 GHz.

[0221] The SST information for 60 GHz signal transmission and reception may include information related to frequency band operation, a channel bitmap, and auxiliary beamforming information.

[0222] Here, the information related to the frequency band operation indicates the frequency band used for signal transmission. The information related to the frequency band operation may be composed of 2 bits and may indicate the frequency band shifted by the SST. For example, if the information related to the frequency band operation is composed of 2 bits, the corresponding information (i.e., the subfield corresponding to the corresponding information) may be composed as shown in Table 1.

[0223] [Table 1]

[0224] index Information related to bandwidth operations 00 2.4GHz 01 5GHz 10 6GHz 11 60GHz

[0225] Furthermore, the channel bitmap may indicate the bandwidth of the available channel through the SST operation in the corresponding frequency band. For example, if 2.4 / 5 / 6 GHz is indicated by the information related to the frequency band operation, the channel bitmap may indicate the available channel bandwidth in 20 MHz channel units. If 60 GHz is indicated by the information related to the frequency band operation, the channel bitmap may indicate the available channel bandwidth in 2.16 MHz channel units. Furthermore, the channel bitmap may consist of 16 bits. In the case of 2.4 GHz, only 2 bits of the MSB / LSB of the channel bitmap may be used, and the remaining bits may be reserved, and in the case of 60 GHz, only 6 bits of the MSB / LSB of the channel bitmap may be used, and the remaining bits may be reserved. Each bit of the channel bitmap may indicate a 20 MHz / 2.16 GHz channel.

[0226] The auxiliary beamforming information may consist of a combination of information about the primary beam based on angle measurements obtained through the beamforming feedback at sub-7 GHz. For example, the auxiliary beamforming information may include primary beam direction information, beamwidth information, antenna pattern, Tx and Rx antenna settings, transmit power, and timestamps.

[0227] Implementation Method 1-2-2

[0228] The 60 GHz operation field may be included in the ECSA frame to indicate that a frequency band in which a beamforming-based transmission / reception process is performed via the ECS is changed to 60 GHz.

[0229] For example, the 60 GHz operation field may be set to 1 bit. When the 60 GHz operation field value is set to 1, this may mean that the channel is shifted to 60 GHz. In this case, the ECSA frame may include 60 GHz operation parameters.

[0230] The above-mentioned 60 GHz operating parameters may include information for simplifying the 60 GHz beamforming training described in the present disclosure (ie, auxiliary beamforming information). Since the configuration of the auxiliary beamforming information has been described above, redundant description will be omitted.

[0231] Implementation Method 1-2-3

[0232] Next-generation wireless LAN systems can essentially support MLO for both APs and STAs. Therefore, signal transmission and reception using 60 GHz can be defined as signal transmission and reception over a single link. MLO allows APs to use the 60 GHz band for signal transmission and reception with non-AP STAs.

[0233] Separate links are set up for sending and receiving 60 GHz signals, and signaling for 60 GHz band operation can be sent over the 2.4 / 5 / 6 GHz links.

[0234] As an example of the present disclosure, the auxiliary beamforming information defined above may be sent on 2.4 / 5 / 6 GHz links to simplify the overhead and process for 60 GHz beamforming training.

[0235] STAs and / or beamformers can perform simplified beamforming training in the 60 GHz band using auxiliary beamforming information received on the 2.4 / 5 / 6 GHz links.

[0236] The above-mentioned embodiments are to 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, the embodiments 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.

[0237] 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.

[0238] 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.

[0239] Industrial Applicability

[0240] The method proposed in the present disclosure is mainly described based on an example of application to a system based on IEEE 802.11, but can be applied to various wireless LANs or wireless communication systems other than the system based on IEEE 802.11.

Claims

1. A method performed by a first station (STA) in a wireless LAN system, the method comprising the following steps: Sending a beamforming feedback matrix to a second STA in the first frequency band; receiving beamforming related information from the second STA, where the beamforming related information includes first information related to a specific beam; as well as performing communication with the second STA based on the beamforming-related information within a second frequency band, wherein the first information is configured based on the beamforming feedback matrix, and The beamforming-related information includes second information related to antenna settings of the first frequency band.

2. The method according to claim 1, wherein The first information includes at least one of a direction, a width, or a range for the specific beam, and At least one of the direction, the width, or the range for the particular beam is based on angular information obtained via the beamforming feedback matrix.

3. The method according to claim 1, wherein At least one of a sector-level scanning (SLS) or a beam refinement protocol (BRP) is performed by the first STA and the second STA within the second frequency band based on at least one of a direction, a width, or a range for the specific beam.

4. The method according to claim 3, wherein: The SLS is performed for a specific sector within the second frequency band corresponding to at least one of the direction, the width, or the range of the specific beam.

5. The method according to claim 1, wherein The second information includes at least one of the following: information indicating whether the antenna pattern of the first frequency band and the antenna pattern of the second frequency band are the same, the number of transmitting antennas and receiving antennas of the first frequency band, or power of antennas of the first frequency band.

6. The method according to claim 1, wherein The beamforming-related information includes third information indicating the second frequency band, and fourth information indicating a bandwidth of an available channel in the second frequency band indicated by the third information.

7. The method according to claim 6, wherein: The fourth information consists of a bitmap indicating the bandwidth of available channels in the second frequency band, and According to the second frequency band, the bandwidth of the available channel is indicated in units of 20 MHz or 2.16 GHz channels.

8. The method according to claim 2, wherein: The beamforming-related information includes at least one of a change value of an angle obtained through the beamforming feedback matrix or time information for measuring the beamforming feedback matrix.

9. The method according to claim 8, wherein Based on a time elapsed based on time information of measuring the beamforming feedback matrix, it is determined whether to perform beamforming based on the beamforming-related information within the second frequency band.

10. The method according to claim 1, wherein The first frequency band is a frequency band below 7 GHz, and The second frequency band is a 60 GHz frequency band.

11. The method according to claim 1, wherein The first STA is the beamformed party, and The second STA is a beamformer.

12. A first station (STA) operating in a wireless LAN system, the first STA 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 beamforming feedback matrix to a second STA within the first frequency band; receiving, through the at least one transceiver, beamforming-related information from the second STA, the beamforming-related information including first information related to a specific beam; and performing communication with the second STA based on the beamforming-related information within a second frequency band through the at least one transceiver, wherein the first information is configured based on the beamforming feedback matrix, and The beamforming-related information includes second information related to antenna settings of the first frequency band.

13. A method performed by a second station (STA) in a wireless LAN system, the method comprising the following steps: receiving a beamforming feedback matrix from a first STA in a first frequency band; Sending beamforming related information to the first STA, where the beamforming related information includes first information related to a specific beam; as well as performing communication with the first STA based on the beamforming-related information within a second frequency band, wherein the first information is configured based on the beamforming feedback matrix, and The beamforming-related information includes second information related to antenna settings of the first frequency band.

14. A second station (STA) implemented in a wireless LAN system, the first STA 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 beamforming feedback matrix from a first STA in a first frequency band; Sending beamforming related information to the first STA through the at least one transceiver, where the beamforming related information includes first information related to a specific beam; and performing communication with the first STA based on the beamforming-related information within a second frequency band through the at least one transceiver, wherein the first information is configured based on the beamforming feedback matrix, and The beamforming-related information includes second information related to antenna settings of the first frequency band.

15. A processing device configured to control a first station (STA) in a wireless LAN system, the processing device comprising: at least one processor; as well as at least one computer memory operatively coupled to the at least one processor and storing instructions for performing operations when executed by the at least one processor, the operations comprising: Sending a beamforming feedback matrix to a second STA in the first frequency band; receiving beamforming-related information from the second STA, where the beamforming-related information includes first information related to a specific beam; and performing communication with the second STA based on the beamforming-related information within a second frequency band, wherein the first information is configured based on the beamforming feedback matrix, and The beamforming-related information includes second information related to antenna settings of the first frequency band.

16. At least one non-transitory computer-readable medium storing at least one instruction, Based on the at least one instruction being executed by the at least one processor, the apparatus for performing communication in the wireless LAN system controls to: Sending a beamforming feedback matrix to a second STA in the first frequency band; receiving beamforming related information from the second STA, where the beamforming related information includes first information related to a specific beam; as well as performing communication with the second STA based on the beamforming-related information within a second frequency band, wherein the first information is configured based on the beamforming feedback matrix, and The beamforming-related information includes second information related to antenna settings of the first frequency band.

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