Method and device for distributed resource unit tone plan-based transmission or reception in wireless LAN system

Abstract

A method and a device for distributed resource unit tone plan-based transmission or reception in a wireless LAN system are disclosed. The method according to one embodiment of the present disclosure may comprise the steps of: receiving a trigger frame including information related to a distributed resource unit (DRU); and transmitting a trigger-based (TB) physical layer protocol data unit (PPDU) based on the DRU. Here, on the basis that the highest 20 MHz channel in an 80 MHz frequency subblock included in the bandwidth of the TB PPDU is not used, a 60 MHz distributed bandwidth can be applied to the 80 MHz frequency subblock.

Description

Method and device for transmitting or receiving based on a distributed resource unit tone plan in a wireless LAN system

[0001] The present disclosure relates to a transmission or reception method and apparatus based on a distributed resource unit tone plan in a Wireless Local Area Network (WLAN) system.

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

[0003] To provide an improved wireless communication environment, advanced technologies for Extremely High Throughput (EHT) are being discussed. For example, technologies for Multiple Input Multiple Output (MIMO) supporting increased bandwidth, efficient utilization of multiple bands, and increased spatial streams, as well as technologies for multiple access points (AP) coordination, are being researched. In particular, various technologies are being studied to support traffic with low latency or real-time characteristics. Furthermore, new technologies to support ultra-high reliability (UHR), including improvements or extensions of EHT technology, are being discussed.

[0004] The technical problem of the present disclosure is to provide a transmission or reception method and apparatus based on a distributed resource unit tone plan in a wireless LAN system.

[0005] The technical problems to be solved in this disclosure are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which this disclosure belongs from the description below.

[0006] A method according to one aspect of the present disclosure may include the step of receiving, by a first station (STA), a trigger frame containing information related to a distributed resource unit (DRU) from a second STA; and the step of transmitting, by the first STA, a trigger-based (TB) physical layer protocol data unit (PPDU) based on the DRU to the second STA. Herein, based on the fact that the highest 20 MHz channel within an 80 MHz frequency subblock included in the bandwidth of the TB PPDU is not used, a 60 MHz distributed bandwidth is applied to the 80 MHz frequency subblock, and for transmission based on the 60 MHz distributed bandwidth, the short training field (STF) portion within the TB PPDU may be configured based on the STF portion in the case of transmitting a 484+242-tone multiple resource unit (MRU) in an 80 MHz frequency subblock where the highest 20 MHz channel is not used.

[0007] A method according to a further aspect of the present disclosure may include the step of transmitting a trigger frame containing information related to a distributed resource unit (DRU) to a first STA by a second station (STA); and the step of receiving a trigger-based (TB) physical layer protocol data unit (PPDU) based on the DRU from the first STA by the second STA. Herein, based on the fact that the highest 20 MHz channel within an 80 MHz frequency subblock included in the bandwidth of the TB PPDU is not used, a 60 MHz distributed bandwidth is applied to the 80 MHz frequency subblock, and for a transmission based on the 60 MHz distributed bandwidth, the short training field (STF) portion within the TB PPDU may be configured based on the STF portion in the case of transmitting a 484+242-tone multiple resource unit (MRU) in an 80 MHz frequency subblock where the highest 20 MHz channel is not used.

[0008] According to the present disclosure, a transmission or reception method and apparatus based on a distributed resource unit tone plan in a wireless LAN system may be provided.

[0009] The effects obtainable from the present disclosure are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art to which the present disclosure belongs from the description below.

[0010] The accompanying drawings, which are included as part of the detailed description to aid in understanding the present disclosure, provide embodiments of the present disclosure and explain the technical features of the present disclosure together with the detailed description.

[0011] FIG. 1 illustrates a block diagram of a wireless communication device according to one embodiment of the present disclosure.

[0012] FIG. 2 is a drawing showing an exemplary structure of a wireless LAN system to which the present disclosure can be applied.

[0013] FIG. 3 is a diagram illustrating a link setup process to which the present disclosure can be applied.

[0014] FIG. 4 is a drawing illustrating a backoff process to which the present disclosure may be applied.

[0015] FIG. 5 is a diagram illustrating a CSMA / CA-based frame transmission operation to which the present disclosure may be applied.

[0016] FIG. 6 is a drawing for illustrating an example of a frame structure used in a wireless LAN system to which the present disclosure may be applied.

[0017] FIG. 7 is a drawing illustrating examples of PPDUs defined in the IEEE 802.11 standard to which the present disclosure may be applied.

[0018] FIG. 8 is a drawing for illustrating an example of a resource unit of a wireless LAN system to which the present disclosure may be applied.

[0019] FIG. 9 is a drawing illustrating another example of a resource unit of a wireless LAN system to which the present disclosure may be applied.

[0020] FIG. 10 is a drawing for illustrating another example of a resource unit of a wireless LAN system to which the present disclosure may be applied.

[0021] FIG. 11 is a drawing for illustrating examples of DRUs to which the present disclosure may be applied.

[0022] FIG. 12 is a drawing showing an exemplary format of a trigger frame to which the present disclosure can be applied.

[0023] FIG. 13 is a diagram illustrating an example of operation by a first STA in a PPDU transmission and reception method based on a DRU tone plan according to the present disclosure.

[0024] FIG. 14 is a diagram illustrating an example of operation by a second STA in a PPDU transmission and reception method based on a DRU tone plan according to the present disclosure.

[0025] FIG. 15 is a diagram illustrating a PPDU transmission and reception procedure between a transmitting STA and a receiving STA according to one embodiment of the present disclosure.

[0026] Hereinafter, preferred embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description disclosed below, together 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 practiced. The following detailed description includes specific details to provide a complete understanding of the present disclosure. However, those skilled in the art will know that the present disclosure may be practiced without such specific details.

[0027] In some cases, to avoid obscuring the concept of the present disclosure, known structures and devices may be omitted or illustrated in the form of a block diagram focusing on the core functions of each structure and device.

[0028] In the present disclosure, when a component is described as being “connected,” “combined,” or “joined” with another component, this may include not only a direct connection but also an indirect connection in which another component exists between them. Furthermore, in the present disclosure, the terms “comprising” or “having” specify the presence of the mentioned features, steps, actions, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, actions, elements, components, and / or groups thereof.

[0029] In the present disclosure, terms such as "first," "second," etc. are used solely for the purpose of distinguishing one component from another and are not used to limit the components, nor do they limit the order or importance of the components unless specifically stated otherwise. Accordingly, within the scope of the present disclosure, a first component in one embodiment may be referred to as a second component in another embodiment, and likewise, a second component in one embodiment may be referred to as a first component in another embodiment.

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

[0031] The embodiments of the present disclosure may be applied to various wireless communication systems. For example, the embodiments of the present disclosure may be applied to wireless LAN systems. For example, the embodiments of the present disclosure may be applied to wireless LANs based on IEEE 802.11a / g / n / ac / ax / be standards. Furthermore, the embodiments of the present disclosure may be applied to wireless LANs based on newly proposed IEEE 802.11bn (or UHR) standards. Additionally, the embodiments of the present disclosure may be applied to wireless LANs based on next-generation standards following IEEE 802.11bn. Furthermore, the embodiments of the present disclosure may be applied to cellular wireless communication systems. For example, they may be applied to cellular wireless communication systems based on LTE (Long Term Evolution) series technologies and 5G NR (New Radio) series technologies of 3GPP (3rd Generation Partnership Project) standards.

[0032] The following describes the technical features to which the examples of the present disclosure may be applied.

[0033] FIG. 1 illustrates a block diagram of a wireless communication device according to one embodiment of the present disclosure.

[0034] The first device (100) and the second device (200) exemplified in FIG. 1 may be replaced with various terms such as terminal, wireless device, WTRU (Wireless Transmit Receive Unit), UE (User Equipment), MS (Mobile Station), UT (user terminal), MSS (Mobile Subscriber Station), MSS (Mobile Subscriber Unit), SS (Subscriber Station), AMS (Advanced Mobile Station), WT (Wireless terminal), or simply user. Additionally, the first device (100) and the second device (200) may be replaced with various terms such as access point (AP), base station (BS), fixed station, Node B, base transceiver system (BTS), network, artificial intelligence (AI) system, road side unit (RSU), repeater, router, relay, gateway, etc.

[0035] The device (100, 200) exemplified in FIG. 1 may be referred to as a station (STA). For example, the device (100, 200) exemplified in FIG. 1 may be referred to by various terms such as a transmitting device, a receiving device, a transmitting STA, or a receiving STA. For example, the STA (110, 200) may perform the role of an access point (AP) or a non-AP. That is, in the present disclosure, the STA (110, 200) may perform the functions of an AP and / or a non-AP. If the STA (110, 200) performs the AP function, it may simply be referred to as an AP, and if the STA (110, 200) performs the non-AP function, it may simply be referred to as a STA. Additionally, in the present disclosure, the AP may also be indicated as an AP STA.

[0036] Referring to FIG. 1, the first device (100) and the second device (200) can transmit and receive wireless signals through various wireless LAN technologies (e.g., IEEE 802.11 series). The first device (100) and the second device (200) may include interfaces for the medium access control (MAC) layer and the physical layer (PHY) that comply with the specifications of the IEEE 802.11 standard.

[0037] In addition, the first device (100) and the second device (200) may additionally support various communication standards other than wireless LAN technology (e.g., 3GPP LTE series, 5G NR series standards, etc.). In addition, the device of the present disclosure may be implemented as various devices such as mobile phones, vehicles, personal computers, AR (Augmented Reality) equipment, VR (Virtual Reality) equipment, etc. Furthermore, the STA of the present specification may support various communication services such as voice calls, video calls, data communication, autonomous driving, MTC (Machine-Type Communication), M2M (Machine-to-Machine), D2D (Device-to-Device), and IoT (Internet-of-Things).

[0038] The first device (100) includes one or more processors (102) and one or more memories (104), and may additionally include one or more transceivers (106) and / or one or more antennas (108). The processor (102) controls the memory (104) and / or transceivers (106) and may be configured to implement the descriptions, functions, procedures, proposals, methods and / or sequences of operation disclosed in this disclosure. For example, the processor (102) may process information within the memory (104) to generate a first information / signal and then transmit a wireless signal containing the first information / signal through the transceiver (106). Additionally, the processor (102) may receive a wireless signal containing a second information / signal through the transceiver (106) and then store information obtained from the signal processing of the second information / signal in the memory (104). Memory (104) may be connected to the processor (102) and may store various information related to the operation of the processor (102). For example, memory (104) may store software code including instructions for performing some or all of the processes controlled by the processor (102) or for performing the descriptions, functions, procedures, proposals, methods, and / or sequences of operation disclosed in this disclosure. Here, the processor (102) and memory (104) may be part of a communication modem / circuit / chip designed to implement wireless LAN technology (e.g., IEEE 802.11 series). A transceiver (106) may be connected to the processor (102) and may transmit and / or receive wireless signals through one or more antennas (108). The transceiver (106) may include a transmitter and / or receiver. The transceiver (106) may be combined with an RF (Radio Frequency) unit. In the present disclosure, the device may refer to a communication modem / circuit / chip.

[0039] The second device (200) includes one or more processors (202) and one or more memories (204), and may additionally include one or more transceivers (206) and / or one or more antennas (208). The processor (202) controls the memory (204) and / or transceivers (206) and may be configured to implement the descriptions, functions, procedures, proposals, methods and / or sequences of operation disclosed in this disclosure. For example, the processor (202) may process information within the memory (204) to generate a third information / signal and then transmit a wireless signal containing the third information / signal through the transceiver (206). Additionally, the processor (202) may receive a wireless signal containing a fourth information / signal through the transceiver (206) and then store information obtained from the signal processing of the fourth information / signal in the memory (204). The memory (204) may be connected to the processor (202) and may store various information related to the operation of the processor (202). For example, the memory (204) may store software code containing instructions for performing some or all of the processes controlled by the processor (202) or for performing the descriptions, functions, procedures, proposals, methods, and / or sequences of operation disclosed 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 through one or more antennas (208). The transceiver (206) may include a transmitter and / or receiver. The transceiver (206) may be used in combination with an RF unit. In the present disclosure, the device may refer to a communication modem / circuit / chip.

[0040] Hereinafter, hardware elements of the device (100, 200) will be described in more detail. Although not limited thereto, 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 Protocol Data Units (PDUs) and / or Service Data Units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and / or flowcharts of operation disclosed in this disclosure. One or more processors (102, 202) may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or flowcharts of operation disclosed in this disclosure. One or more processors (102, 202) may generate a signal (e.g., a baseband signal) including a PDU, SDU, message, control information, data, or information according to the functions, procedures, proposals, and / or methods disclosed in this disclosure and provide it to one or more transceivers (106, 206). One or more processors (102, 202) may receive a signal (e.g., a baseband signal) from one or more transceivers (106, 206) and may obtain a PDU, SDU, message, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed in this disclosure.

[0041] One or more processors (102, 202) may be referred to as a controller, microcontroller, microprocessor, or microcomputer. One or more processors (102, 202) may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Digital Signal Processing Devices (DSPDs), one or more Programmable Logic Devices (PLDs), or one or more Field Programmable Gate Arrays (FPGAs) may be included in one or more processors (102, 202). The descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed in this disclosure may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. Firmware or software configured to perform the descriptions, functions, procedures, proposals, methods, and / or operation sequences disclosed in this disclosure may be included in one or more processors (102, 202) or stored in one or more memories (104, 204) and driven by one or more processors (102, 202). The descriptions, functions, procedures, proposals, methods, and / or operation sequences disclosed in this disclosure may be implemented using firmware or software in the form of code, instructions, and / or sets of instructions.

[0042] One or more memories (104, 204) may be connected to one or more processors (102, 202) and may store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. One or more memories (104, 204) may be composed of ROM, RAM, EPROM, flash memory, hard drive, registers, cache memory, computer read storage media, and / or combinations thereof. One or more memories (104, 204) may be located inside and / or outside of one or more processors (102, 202). Additionally, one or more memories (104, 204) may be connected to one or more processors (102, 202) through various technologies such as wired or wireless connections.

[0043] One or more transceivers (106, 206) may transmit user data, control information, wireless signals / channels, etc., as mentioned in the methods and / or operation 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 mentioned in the descriptions, functions, procedures, proposals, methods and / or operation flowcharts, etc., disclosed 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. Additionally, 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. Additionally, 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., as described in the descriptions, functions, procedures, proposals, methods, and / or flowcharts of operation disclosed in this disclosure through one or more antennas (108, 208). In this disclosure, one or more antennas may be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports). One or more transceivers (106, 206) can convert the received wireless signal / channel, etc. from an RF band signal to a baseband signal in order to process the received user data, control information, wireless signal / channel, etc. using one or more processors (102, 202).One or more transceivers (106, 206) can convert user data, control information, wireless signals / channels, etc. processed using one or more processors (102, 202) from baseband signals to RF band signals. To this end, one or more transceivers (106, 206) may include (analog) oscillators and / or filters.

[0044] For example, one of the STAs (100, 200) may perform the intended operation of an AP, and the other of the STAs (100, 200) may perform the intended operation of a non-AP STA. For example, the transceiver (106, 206) of FIG. 1 may perform the operation of transmitting and receiving signals (e.g., packets or PPDU (Physical Layer Protocol Data Unit) according to IEEE 802.11a / b / g / n / ac / ax / be / bn, etc.). Additionally, the operation of generating transmission and reception signals or performing data processing or calculations in advance for transmission and reception signals by various STAs in the present disclosure may be performed by the processor (102, 202) of FIG. 1. For example, an example of an operation to generate a transmission and reception signal or to perform data processing or operations in advance for a transmission and reception signal may include: 1) an operation to determine / acquire / configure / operate / decode / encode bit information of fields (SIG (signal), STF (short training field), LTF (long training field), Data, etc.) included in the PPDU; 2) an operation to determine / configure / acquire time resources or frequency resources (e.g., subcarrier resources) used for fields (SIG, STF, LTF, Data, etc.) included in the PPDU; 3) an operation to determine / configure / acquire specific sequences (e.g., pilot sequence, STF / LTF sequence, extra sequence applied to SIG) used for fields (SIG, STF, LTF, Data, etc.) included in the PPDU; 4) power control operations and / or power saving operations applied to the STA; and 5) operations related to determining / acquiring / configuring / operating / decoding / encoding of an ACK signal. In addition, in the following example, various information (e.g., information related to fields, subfields, control fields, parameters, power, etc.) used by various STAs for determining / acquiring / configuring / calculating / decoding / encoding of transmission and reception signals can be stored in the memory (104, 204) of FIG. 1.

[0045] In the following, the downlink (DL) refers to a link for communication from an AP STA to a non-AP STA, and downlink PPDUs, packets, signals, etc., can be transmitted and received through the downlink. In downlink communication, the transmitter may be part of the AP STA, and the receiver may be part of the non-AP STA. The uplink (UL) refers to a link for communication from a non-AP STA to an AP STA, and uplink PPDUs, packets, signals, etc., can be transmitted and received through the uplink. In uplink communication, the transmitter may be part of the non-AP STA, and the receiver may be part of the AP STA.

[0046] FIG. 2 is a drawing showing an exemplary structure of a wireless LAN system to which the present disclosure can be applied.

[0047] The structure of a wireless LAN system can be composed of multiple components. Through the interaction of multiple components, a wireless LAN that supports STA mobility transparent to the upper layer can be provided. A Basic Service Set (BSS) corresponds to the basic building block of a wireless LAN. Figure 2 exemplarily illustrates the existence of two BSSs (BSS1 and BSS2) and the inclusion of two STAs as members of each BSS (STA1 and STA2 are included in BSS1, and STA3 and STA4 are included in BSS2). In Figure 2, the ellipse representing the BSS can also be understood as representing the coverage area where the STAs included in the corresponding BSS maintain communication. This area can be referred to as a Basic Service Area (BSA). If a STA moves outside the BSA, it becomes unable to communicate directly with other STAs within that BSA.

[0048] Excluding the DS illustrated in Fig. 2, the most basic type of BSS in a wireless LAN is the Independent BSS (IBSS). For example, an IBSS can have a minimal form consisting of only two STAs. For instance, assuming other components are omitted, a BSS1 composed of only STA1 and STA2, or a BSS2 composed of only STA3 and STA4, can each be considered a representative example of an IBSS. Such a configuration is possible when the STAs can communicate directly without an AP. Furthermore, this type of wireless LAN is not configured through pre-planning but can be configured when a LAN is needed, and this can be referred to as an ad-hoc network. Since an IBSS does not include an AP, there is no centralized management entity. In other words, in an IBSS, STAs are managed in a distributed manner. In IBSS, all STAs can be mobile STAs, and since connections to distributed systems (DS) are not allowed, they form a self-contained network.

[0049] The membership of an STA in a BSS can be dynamically changed by the STA being turned on or off, or by the STA entering or leaving the BSS area. To become a member of a BSS, an STA can join the BSS using a synchronization process. To access all services of the BSS infrastructure, an STA must be associated with the BSS. This association can be configured dynamically and may include the use of a Distribution System Service (DSS).

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

[0051] DS refers to a structure in which BSSs are interconnected. Specifically, as shown in FIG. 2, a BSS may exist as a component in 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). In this regard, the Wireless Medium (WM) and the DSM can be logically distinguished. Each logical medium is used for a different purpose and is utilized by different components. These media are not limited to being identical or different. The flexibility of the wireless LAN structure (DS structure or other network structure) can be explained by the fact that multiple media are logically distinct in this way. That is, the wireless LAN structure can be implemented in various ways, and the corresponding wireless LAN structure can be specified independently by the physical characteristics of each implementation.

[0052] DS can support mobile devices by providing seamless integration of multiple BSSs and providing logical services necessary for handling addresses to destinations. Additionally, DS may include a component called a portal that acts as a bridge for connecting the wireless LAN with another network (e.g., IEEE 802.X).

[0053] An AP refers to an entity that enables access to a DS via a WM for combined non-AP STAs and also possesses the functionality of an STA. Data movement between a BSS and a DS can be performed through the AP. For example, STA2 and STA3 shown in FIG. 2 possess the functionality of an STA and provide the ability for combined non-AP STAs (STA1 and STA4) to access a DS. Furthermore, since all APs fundamentally correspond to STAs, all APs are addressable entities. The address used by the AP for communication on the WM and the address used by the AP for communication on the DSM do not necessarily have to be the same. A BSS composed of an AP and one or more STAs can be referred to as an infrastructure BSS.

[0054] Data transmitted from one of the STA(s) coupled to the AP to the STA address of the AP can always be received at an uncontrolled port and processed by an IEEE 802.1X port access entity. Additionally, if the controlled port is authenticated, the transmitted data (or frame) can be forwarded to the DS.

[0055] In addition to the structure of the aforementioned DS, an Extended Service Set (ESS) may be configured to provide wider coverage.

[0056] An ESS refers to a network of arbitrary size and complexity composed of DSs and BSSs. An ESS can correspond to a set of BSSs connected to a single DS. However, an ESS does not contain a DS. An ESS network is characterized by appearing as an IBSS at 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 a single ESS can have the same Service Set Identification (SSID). The SSID is distinct from the BSSID, which is the identifier for the BSS.

[0057] In wireless LAN systems, no assumptions are made regarding the relative physical locations of BSSs, and all of the following forms are possible. BSSs may partially overlap, which is a form commonly used to provide continuous coverage. Additionally, BSSs may not be physically connected, and logically, there is no limit to the distance between BSSs. Furthermore, BSSs may be located in the same physical location, which can be used to provide redundancy. Also, one (or more) IBSS or ESS networks may physically exist in the same space as one (or more) ESS networks. This may apply to ESS network forms such as when an ad-hoc network operates at a location where an ESS network exists, when wireless networks that physically overlap are configured by different organizations, or when two or more different access and security policies are required at the same location.

[0058] FIG. 3 is a diagram illustrating a link setup process to which the present disclosure can be applied.

[0059] In order for an STA to set up a link and transmit and receive data on a network, it must first discover the network, perform authentication, establish an association, and go through authentication procedures for security. The link setup process can also be referred to as the session initiation process or the session setup process. Additionally, the processes of discovery, authentication, association, and security setup in the link setup process can be collectively referred to as the association process.

[0060] In step S310, the STA may perform a network discovery operation. The network discovery operation may include the STA's scanning operation. That is, in order for the STA to access a network, it must find a network it can join. Before joining a wireless network, the STA must identify a compatible network, and the process of identifying networks existing in a specific area is called scanning.

[0061] Scanning methods include active scanning and passive scanning. Figure 3 illustrates a network discovery operation that includes an active scanning process as an example. In active scanning, the STA performing the scanning moves between channels to search for nearby APs, transmits a probe request frame, and waits for a response. The responder transmits a probe response frame as a response to the probe request frame to the STA that transmitted the probe request frame. Here, the responder may be the STA that last transmitted a beacon frame from the BSS of the channel being scanned. In a BSS, the AP becomes the responder because it transmits the beacon frame; however, in an IBSS, the responder is not constant because STAs within the IBSS take turns transmitting the beacon frame. For example, an STA that transmits a probe request frame on channel 1 and receives a probe response frame on channel 1 can store BSS-related information included in the received probe response frame and move to the next channel (e.g., channel 2) to perform scanning in the same way (i.e., transmit and receive probe request / response on channel 2).

[0062] Although not illustrated in FIG. 3, the scanning operation may be performed using a passive scanning method. In passive scanning, the STA performing the scanning waits for a beacon frame while switching between channels. A beacon frame is one of the management frames defined in IEEE 802.11, which is periodically transmitted to announce the presence of a wireless network and to allow the scanning STA to find the wireless network and join it. In a BSS, the AP performs the role of periodically transmitting beacon frames, and in an IBSS, the STAs within the IBSS take turns transmitting beacon frames. When the scanning STA receives a beacon frame, it stores the information about the BSS included in the beacon frame and records the beacon frame information in each channel while moving to another channel. The STA that receives the beacon frame stores the BSS-related information included in the received beacon frame and moves to the next channel, and can perform scanning in the next channel in the same way. When comparing active scanning and passive scanning, active scanning has the advantage of lower delay and power consumption than passive scanning.

[0063] After the STA discovers the network, an authentication process may be performed in step S320. This authentication process may be referred to as the first authentication process to clearly distinguish it from the security setup operation in step S340 described later.

[0064] The authentication process involves the STA sending an authentication request frame to the AP, and the AP sending an authentication response frame to the STA in response. The authentication frame used in the authentication request / response corresponds to a management frame.

[0065] The authentication frame may include information regarding the authentication algorithm number, authentication transaction sequence number, status code, challenge text, Robust Security Network (RSN), Finite Cyclic Group, etc. These are some examples of information that may be included in the authentication request / response frame, and they may be replaced with other information or additional information may be included.

[0066] The STA can send an authentication request frame to the AP. Based on the information contained in the received authentication request frame, the AP can determine whether to allow authentication for the STA. The AP can provide the result of the authentication process to the STA through an authentication response frame.

[0067] After the STA is successfully authenticated, the association process can be performed in step S330. The association process includes the STA transmitting an association request frame to the AP, and in response, the AP transmitting an association response frame to the STA.

[0068] For example, the association request frame may include information regarding various capabilities, beacon listen interval, service set identifier (SSID), supported rates, supported channels, RSN, mobility domain, supported operating classes, Traffic Indication Map Broadcast request, interworking service capabilities, etc. For example, the association response frame may include information regarding various capabilities, status code, Association ID (AID), supported rates, Enhanced Distributed Channel Access (EDCA) parameter set, Received Channel Power Indicator (RCPI), Received Signal to Noise Indicator (RSNI), mobility domain, timeout interval (e.g., association comeback time), overlapping BSS scan parameters, TIM broadcast response, Quality of Service (QoS) map, etc. These are some examples of information that may be included in a combined request / response frame, and may be replaced with other information or additional information may be included.

[0069] After the STA is successfully joined to the network, a security setup process can be performed in step S340. The security setup process in step S340 may be described as an authentication process through RSNA (Robust Security Network Association) requests / responses, and the authentication process in step S320 may be referred to as the first authentication process, and the security setup process in step S340 may simply be referred to as the authentication process.

[0070] The security setup process of step S340 may include, for example, a private key setup process through a 4-way handshake via an EAPOL (Extensible Authentication Protocol over LAN) frame. Additionally, the security setup process may be performed according to a security method not defined in the IEEE 802.11 standard.

[0071] FIG. 4 is a drawing illustrating a backoff process to which the present disclosure may be applied.

[0072] In wireless LAN systems, the basic access mechanism for MAC (Medium Access Control) is the CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) mechanism. The CSMA / CA mechanism is also known as the Distributed Coordination Function (DCF) of IEEE 802.11 MAC, and it basically employs a "listen before talk" access mechanism. According to this type of access mechanism, the AP and / or STA may perform Clear Channel Assessment (CCA) to sense the wireless channel or medium for a predetermined time interval (e.g., DIFS (DCF Inter-Frame Space)) before starting transmission. If the sensing result determines that the medium is in an idle status, it starts transmitting a frame through that medium. On the other hand, if the medium is detected to be occupied or busy, the AP and / or STA may not start its own transmission but wait by setting a delay period for medium access (e.g., a random backoff period) before attempting to transmit a frame. By applying a random backoff period, multiple STAs are expected to attempt to transmit frames after waiting for different periods of time, thereby minimizing collisions.

[0073] In addition, the IEEE 802.11 MAC protocol provides a Hybrid Coordination Function (HCF). The HCF is based on the aforementioned Point Coordination Function (PCF). The PCF is a polling-based synchronous access method that periodically polls to ensure all receiving APs and / or STAs can receive data frames. Furthermore, the HCF includes Enhanced Distributed Channel Access (EDCA) and Controlled Channel Access (HCCA). EDCA is a contention-based access method for a provider to offer data frames to multiple users, while HCCA uses a non-contention-based channel access method utilizing a polling mechanism. Additionally, the HCF includes a media access mechanism to improve the Quality of Service (QoS) of the wireless LAN and can transmit QoS data during both the Contention Period (CP) and the Contention-Free Period (CFP).

[0074] Referring to FIG. 4, the operation based on the random backoff period is described. When a medium in an occupied / busy state changes to an idle state, multiple STAs may attempt to transmit data (or frames). As a measure to minimize collisions, each STA may select a random backoff count and attempt transmission after waiting for the corresponding slot time. The random backoff count has a pseudo-random integer value and can be determined as one of the values ​​in the range from 0 to CW. Here, CW is the Contention Window parameter value. The CW parameter is given an initial value of CWmin, but in the case of transmission failure (e.g., failure to receive an ACK for a transmitted frame), it may take a value twice that amount. When the CW parameter value becomes CWmax, data transmission may be attempted while maintaining the CWmax value until data transmission is successful; if data transmission is successful, it is reset to the CWmin value. The values ​​of CW, CWmin, and CWmax are 2 n It is desirable to set it to -1 (n=0, 1, 2, ...).

[0075] When the random backoff process begins, the STA continues to monitor the media while counting down the backoff slots according to the determined backoff count value. When the media is monitored as occupied, it stops the countdown and waits, and when the media becomes idle, it resumes the remaining countdown.

[0076] In the example of Fig. 4, when a packet to be transmitted arrives at the MAC of STA3, STA3 confirms that the medium is idle for DIFS and can immediately transmit the frame. The remaining STAs monitor whether the medium is occupied or busy and wait. Meanwhile, data to be transmitted may also arise from each of STA1, STA2, and STA5, and each STA can perform a countdown of the backoff slot according to a random backoff count value selected by each after waiting for DIFS when the medium is monitored to be idle. Assume the case where STA2 selects the smallest backoff count value and STA1 selects the largest backoff count value. That is, this exemplifies a case where, at the point when STA2 finishes the backoff count and starts transmitting the frame, the remaining backoff time of STA5 is shorter than the remaining backoff time of STA1. STA1 and STA5 pause the countdown briefly and wait while STA2 occupies the medium. When STA2's possession ends and the medium becomes idle again, STA1 and STA5 wait for DIFS and then resume the paused backoff count. That is, they can start transmitting a frame after counting down the remaining backoff slots corresponding to the remaining backoff time. Since STA5's remaining backoff time was shorter than STA1's, STA5 starts transmitting the frame. While STA2 is occupying the medium, data to be transmitted may also be generated by STA4. From STA4's perspective, when the medium becomes idle, it waits for DIFS, performs a countdown based on a random backoff count value selected by itself, and can start transmitting a frame. The example in Figure 4 illustrates a case where STA5's remaining backoff time happens to match STA4's random backoff count value; in this case, a collision may occur between STA4 and STA5. If a collision occurs, neither STA4 nor STA5 receives an ACK, resulting in a failure to transmit data.In this case, STA4 and STA5 can double the CW value, select a random backoff count value, and perform a countdown. STA1 waits while the medium is occupied due to transmission by STA4 and STA5, and when the medium becomes idle, it waits for DIFS, and then can start transmitting frames after the remaining backoff time has passed.

[0077] As shown in the example in Fig. 4, a data frame is a frame used for transmitting data that is forwarded to an upper layer, and can be transmitted after a backoff performed after the elapsed time of DIFS from when the medium becomes idle. Additionally, a management frame is a frame used for exchanging management information that is not forwarded to an upper layer, and is transmitted after a backoff performed after the elapsed time of an IFS such as DIFS or PIFS (Point coordination function IFS). Subtypes of management frames include Beacon, Association request / response, re-association request / response, probe request / response, and authentication request / response. A control frame is a frame used to control access to the medium. Subtype frames of control frames include RTS (Request-To-Send), CTS (Clear-To-Send), ACK (Acknowledgment), PS-Poll (Power Save-Poll), Block ACK (BlockAck), Block ACK Request (BlockACKReq), NDP Announcement (null data packet announcement), and Trigger. If a control frame is not an acknowledgment frame of a previous frame, it is transmitted after a backoff performed after the elapsed DIFS; if it is an acknowledgment frame of a previous frame, it is transmitted after the elapsed SIFS (short IFS) without a backoff. The type and subtype of a frame can be identified by the type field and subtype field within the Frame Control (FC) field.

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

[0079] FIG. 5 is a diagram illustrating a CSMA / CA-based frame transmission operation to which the present disclosure may be applied.

[0080] As previously mentioned, the CSMA / CA mechanism includes virtual carrier sensing in addition to physical carrier sensing, where the STA directly senses the medium. Virtual carrier sensing is intended to mitigate problems that may occur in medium access, such as the hidden node problem. For virtual carrier sensing, the STA's MAC can utilize the Network Allocation Vector (NAV). The NAV is a value that indicates to other STAs the time remaining until the medium becomes available, provided that the STA currently using or authorized to use the medium is using it. Therefore, the value set as the NAV corresponds to the period during which the medium is scheduled to be used by the STA transmitting the frame, and the STA receiving the NAV value is prohibited from accessing the medium during that period. For example, the NAV can be set based on the value of the "duration" field in the frame's MAC header.

[0081] In the example of FIG. 5, it is assumed that STA1 intends to transmit data to STA2, and STA3 is located in a position where it can overhear part or all of the frames transmitted and received between STA1 and STA2.

[0082] In order to reduce the possibility of collisions between multiple STAs in a CSMA / CA-based frame transmission operation, a mechanism utilizing RTS / CTS frames may be applied. In the example of FIG. 5, while STA1 is transmitting, the medium may be determined to be idle based on the carrier sensing result of STA3. That is, STA1 may be a hidden node to STA3. Alternatively, in the example of FIG. 5, while STA2 is transmitting, the medium may be determined to be idle based on the carrier sensing result of STA3. That is, STA2 may be a hidden node to STA3. By exchanging RTS / CTS frames before performing data transmission and reception between STA1 and STA2, it is possible to prevent a STA outside the transmission range of either STA1 or STA2, or a STA outside the carrier sensing range for transmission from STA1 or STA3, from attempting to occupy the channel during data transmission and reception between STA1 and STA2.

[0083] Specifically, STA1 can determine whether the 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 magnitude or signal correlation detected in the channel. Additionally, in terms of virtual carrier sensing, STA1 can determine the channel occupancy state using a NAV (network allocation vector) timer.

[0084] If the channel is idle during DIFS, STA1 can send an RTS frame to STA2 after performing backoff. If STA2 receives the RTS frame, it can send a CTS frame to STA1 as a response to the RTS frame after SIFS.

[0085] If STA3 cannot overhear a CTS frame from STA2 but can overhear an RTS frame from STA1, STA3 can set a NAV timer for the duration of subsequently transmitted frames (e.g., SIFS + CTS frame + SIFS + data frame + SIFS + ACK frame) using the duration information included in the RTS frame. Alternatively, if STA3 cannot overhear an RTS frame from STA1 but can overhear a CTS frame from STA2, STA3 can set a NAV timer for the duration of subsequently transmitted frames (e.g., SIFS + data frame + SIFS + ACK frame) using the duration information included in the CTS frame. That is, if STA3 can overhear one or more of the RTS or CTS frames from one or more of STA1 or STA2, it can set a NAV accordingly. If STA3 receives a new frame before the NAV timer expires, it can update the NAV timer using the duration information contained in the new frame. STA3 does not attempt channel access until the NAV timer expires.

[0086] If STA1 receives a CTS frame from STA2, it may transmit a data frame to STA2 after SIFS from the time the reception of the CTS frame is completed. If STA2 successfully receives the data frame, it may transmit an ACK frame to STA1 as an acknowledgment to the data frame after SIFS. STA3 may determine whether the channel is in use through carrier sensing when the NAV timer expires. If STA3 determines that the channel is not in use by another terminal during DIFS from the time the NAV timer expires, it may attempt channel access after a contention window (CW) based on random backoff has passed.

[0087] FIG. 6 is a drawing for illustrating an example of a frame structure used in a wireless LAN system to which the present disclosure may be applied.

[0088] Based on instructions or primitives (meaning a set of instructions or parameters) from the MAC layer, the PHY layer can prepare the MPDU (MAC PDU) to be transmitted. For example, upon receiving an instruction from the MAC layer requesting the start of transmission, the PHY layer switches to transmit mode and can construct the information provided by the MAC layer (e.g., data) into a frame for transmission. Additionally, if the PHY layer detects a valid preamble of a received frame, it monitors the preamble header and sends an instruction to the MAC layer indicating the start of reception.

[0089] As such, information transmission and reception in wireless LAN systems are carried out in the form of frames, and for this purpose, the Physical Layer Protocol Data Unit (PPDU) format is defined.

[0090] A basic PPDU may include a Short Training Field (STF), a Long Training Field (LTF), a Signal (SIGNAL) field, and a Data field. The most basic (e.g., the non-HT (High Throughput)) PPDU format illustrated in FIG. 7 may consist only of Legacy-STF (Legacy-STF), Legacy-LTF (Legacy-LTF), Legacy-SIG (Legacy-SIG) fields and a 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.), additional (or other types of) RL-SIG, U-SIG, non-legacy SIG fields, 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. More specific details will be described later with reference to FIG. 7.

[0091] STF is a signal for signal detection, AGC (Automatic Gain Control), diversity selection, and precise time synchronization, while LTF is a signal for channel estimation and frequency error estimation. STF and LTF can be considered signals for synchronization and channel estimation in the OFDM physical layer.

[0092] The SIG field may contain various information related to the transmission and reception of the PPDU. 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 contain information regarding the modulation and coding rates of the data. For example, the 12-bit Length field may contain information regarding the length or time duration of the PPDU. For example, the value of the 12-bit Length field may be determined based on the type of the PPDU. For example, 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 HE PPDUs, the value of the Length field may be determined as a multiple of 3 + 1 or a multiple of 3 + 2.

[0093] The data field may include a SERVICE field, a PSDU (Physical layer Service Data Unit), and PPDU TAIL bits, and may also include padding bits if necessary. Some bits of the SERVICE field may be used for synchronization of the descrambler at the receiver. The PSDU corresponds to a MAC PDU defined at the MAC layer and may contain data generated or used by the upper layer. The PPDU TAIL bits may be used to return the encoder to a 0 state. Padding bits may be used to adjust the length of the data field to a predetermined unit.

[0094] A 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 is composed of a MAC PDU and can be transmitted or received through the PSDU of the data portion in the PPDU format.

[0095] The MAC header includes a Frame Control field, a Duration / ID field, an Address field, etc. The Frame Control field may contain control information necessary for transmitting or receiving frames. The Duration / ID field may be set as the time for transmitting the corresponding frame. Address subfields may indicate the frame's receiver address, transmitter address, destination address, and source address, and some address subfields may be omitted. Specific details regarding each subfield of the MAC header, including Sequence Control, QoS Control, and HT Control subfields, can be found in the IEEE 802.11 standard document.

[0096] The Null-Data PPDU (NDP) format refers to a PPDU format that does not include a data field. In other words, NDP is a frame format that includes the PPDU preamble (i.e., L-STF, L-LTF, L-SIG fields, and additionally, non-legacy SIG, non-legacy STF, and non-legacy LTF if present) from a standard PPDU format, but excludes the remaining parts (i.e., the data field).

[0097] FIG. 7 is a drawing illustrating examples of PPDUs defined in the IEEE 802.11 standard to which the present disclosure may be applied.

[0098] Various forms of PPDU have been used in standards such as IEEE 802.11a / g / n / ac / ax. 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 the non-HT PPDU format (Fig. 7(a)).

[0099] The HT PPDU format (IEEE 802.11n) additionally includes HT-SIG, HT-STF, and HT-LFT(s) fields in addition to the basic PPDU format. The HT PPDU format illustrated in FIG. 7(b) may be referred to as the HT-mixed format. Additionally, an HT-greenfield format PPDU may be defined, which corresponds to a format consisting of HT-GF-STF, HT-LTF1, HT-SIG, one or more HT-LTFs, and a Data field, without including L-STF, L-LTF, and L-SIG (not shown).

[0100] An example of the VHT PPDU format (IEEE 802.11ac) includes the VHT SIG-A, VHT-STF, VHT-LTF, and VHT-SIG-B fields in addition to the basic PPDU format (Fig. 7(c)).

[0101] An example of the HE PPDU format (IEEE 802.11ax) includes the RL-SIG (Repeated L-SIG), HE-SIG-A, HE-SIG-B, HE-STF, HE-LTF(s), and PE (Packet Extension) fields in addition to the basic PPDU format (Fig. 7(d)). Depending on specific examples of the HE PPDU format, some fields may be excluded or their lengths may vary. For example, the HE-SIG-B field is included in the HE PPDU format for multiple users (MU), but is not included in the HE PPDU format for single users (SU). Additionally, the HE trigger-based (TB) PPDU format does not include HE-SIG-B, and the length of the HE-STF field may vary to 8 microseconds (us). The HE ER (Extended Range) SU PPDU format does not include the HE-SIG-B field, and the length of the HE-SIG-A field may vary to 16us. For example, RL-SIG can be configured identically to L-SIG. Based on the presence of RL-SIG, the receiving STA can determine that the received PPDU is a HE PPDU or the EHT PPDU described later.

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

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

[0104] The EHT-SIG is omitted in the EHT TB PPDU of FIG. 7(f) compared to the EHT MU PPDU. A STA that receives a trigger for UL MU transmission (e.g., a trigger frame or TRS (triggered response scheduling)) can perform UL transmission based on the EHT TB PPDU format.

[0105] The L-STF, L-LTF, L-SIG, RL-SIG, U-SIG (Universal SIGNAL), and EHT-SIG fields can be encoded and modulated so that demodulation and decoding can be attempted even on legacy STAs, and mapped based on a defined subcarrier frequency interval (e.g., 312.5 kHz). These can be referred to as pre-EHT modulated fields. Next, the EHT-STF, EHT-LTF, Data, and PE fields can be encoded and modulated so that they can be demodulated and decoded by a STA that has successfully decoded a non-legacy SIG (e.g., U-SIG and / or EHT-SIG) to obtain the information contained in the corresponding fields, and mapped based on a defined subcarrier frequency interval (e.g., 78.125 kHz). These can be referred to as EHT modulated fields.

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

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

[0108] U-SIGs can be configured in 20 MHz units. For example, if an 80 MHz PPDU is configured, the same U-SIG can be duplicated in 20 MHz units. That is, four identical U-SIGs can be included within an 80 MHz PPDU. If the bandwidth exceeds 80 MHz, for example, for a 160 MHz PPDU, the U-SIG of the first 80 MHz unit and the U-SIG of the second 80 MHz unit may be different.

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

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

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

[0112] For example, the version-independent bits of 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 U-SIG may include a 1-bit UL / DL flag field. The first value of the 1-bit UL / DL flag field relates to UL communication, and the second value of the UL / DL flag field relates to DL communication. The version-independent bits of U-SIG may include information regarding the length of the TXOP (transmission opportunity) and information regarding the BSS color ID.

[0113] For example, the version-dependent bits of U-SIG may contain information that directly or indirectly indicates the type of PPDU (e.g., SU PPDU, MU PPDU, TB PPDU, etc.).

[0114] Information necessary for PPDU transmission and reception may be included in the U-SIG. For example, the U-SIG may further include information regarding bandwidth, information regarding MCS techniques applied to non-legacy SIGs (e.g., EHT-SIG or UHR-SIG, etc.), information indicating whether DCM (dual carrier modulation) techniques (e.g., techniques to achieve an effect similar to frequency diversity by reusing the same signal on two subcarriers) are applied to non-legacy SIGs, information regarding the number of symbols used for non-legacy SIGs, and information regarding whether non-legacy SIGs are generated across the entire band.

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

[0116] Preamble puncturing may refer to the transmission of a PPDU in which a signal is not present in one or more frequency units within the PPDU bandwidth. For example, the size of the frequency unit (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 larger.

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

[0118] Non-legacy SIGs, such as HE-SIG-B and EHT-SIG, may include common fields and user-specific fields. Common fields and user-specific fields may be coded individually.

[0119] In some cases, the common field may be omitted. For example, in a compression mode where non-OFDMA (orthogonal frequency multiple access) is applied, the common field may be omitted, and multiple STAs may receive PPDUs (e.g., the data field of the PPDU) over the same frequency band. In a non-compression mode where OFDMA is applied, multiple users may receive PPDUs (e.g., the data field of the PPDU) over different frequency bands.

[0120] The number of user-specific fields can be determined based on the number of users. A single user block field can contain up to two user fields. Each user field may be related to MU-MIMO allocation or non-MU-MIMO allocation.

[0121] The common field may include CRC bits and Tail bits, the length of the CRC bits may be determined to be 4 bits, and the length of the Tail bits 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 regarding the location of the RU to which a plurality of users (i.e., a plurality of receiving STAs) are allocated.

[0122] An RU may include multiple subcarriers (or tones). An RU may be used when transmitting signals to multiple STAs based on the OFDMA technique. Additionally, an RU may be defined when transmitting signals to a single STA. Resources may be allocated on an RU basis for non-legacy STF, non-legacy LTF, and Data fields.

[0123] Applicable RU sizes can be defined according to the PPDU bandwidth. RUs may be defined identically or differently for the applicable PPDU format (e.g., HE PPDU, EHT PPDU, UHR PPDU, etc.). For example, in the case of an 80 MHz PPDU, the RU placement for HE PPDU and EHT PPDU may differ. The applicable RU sizes, number of RUs, RU locations, DC (direct current) subcarrier locations and numbers, null subcarrier locations and numbers, and guard subcarrier locations and numbers for each PPDU bandwidth can be referred to as a tone-plan. For example, a tone-plan for a wide bandwidth may be defined as a multiple repetition of a tone-plan for a low bandwidth.

[0124] RUs of various sizes can be defined as 26-ton RUs, 52-ton RUs, 106-ton RUs, 242-ton RUs, 484-ton RUs, 996-ton RUs, 2x996-ton RUs, 4x996-ton RUs, etc. An MRU (multiple RU) is distinguished from multiple individual RUs and corresponds to a group of subcarriers composed of multiple RUs. For example, one MRU can be defined as 52+26-tons, 106+26-tons, 484+242-tons, 996+484-tons, 996+484+242-tons, 2x996+484-tons, 3x996-tons, or 3x996+484-tons. In addition, multiple RUs constituting a single MRU may be continuous or non-continuous in the frequency domain.

[0125] The specific size of the RU may be reduced or expanded. Accordingly, the specific size of each RU (i.e., the number of corresponding tones) in this disclosure is not limited and is exemplary. Additionally, within a given bandwidth (e.g., 20, 40, 80, 160, 320 MHz, ...) in this disclosure, the number of RUs may vary depending on the RU size.

[0126] The names of the respective fields in the PPDU formats of FIG. 7 are exemplary and the scope of the present disclosure is not limited by such names. Furthermore, the examples of the present disclosure may be applied not only to the PPDU formats exemplified in FIG. 7, but also to new PPDU formats based on the PPDU formats of FIG. 7 in which some fields are excluded and / or some fields are added.

[0127] Resource Unit

[0128] FIGS. 8 to 10 are drawings for illustrating examples of resource units of a wireless LAN system to which the present disclosure may be applied.

[0129] With reference to FIGS. 8 to 10, a resource unit (RU) defined in a wireless LAN system will be described. The RU may include multiple subcarriers (or tones). The RU may be used when transmitting signals to multiple STAs based on the OFDMA technique. Additionally, the RU may be defined when transmitting signals to a single STA. The RU may be used for the STF, LTF, data fields, etc., of a PPDU.

[0130] As illustrated in FIGS. 8 to 10, RUs corresponding to different numbers of tones (i.e., subcarriers) can be used to form some fields of a 20 MHz, 40 MHz, or 80 MHz X-PPDU (X is HE, EHT, etc.). For example, resources can be allocated in units of the illustrated RUs for the X-STF, X-LTF, and Data fields.

[0131] FIG. 8 is a diagram showing an exemplary arrangement of resource units (RU) used in the 20 MHz band.

[0132] As shown at the top of FIG. 8, 26 units (i.e., units corresponding to 26 tones) may be allocated. Six tones may be used as a guard band in the leftmost band of the 20 MHz band, and five tones may be used as a guard band in the rightmost band of the 20 MHz band. Additionally, seven DC tones may be inserted in the center band, i.e., the DC band, and 26 units corresponding to 13 tones may exist on the left and right sides of the DC band. Furthermore, 26, 52, and 106 units may be allocated to other bands. Each unit may be allocated for an STA or a user.

[0133] The RU arrangement of FIG. 8 is utilized not only for situations involving multiple users (MU) but also for situations involving a single user (SU), in which case it is possible to use one 242-unit as shown at the bottom of FIG. 8. In this case, three DC tones can be inserted.

[0134] In the example of FIG. 8, various sizes of RUs, namely 26-RU, 52-RU, 106-RU, 242-RU, etc., are exemplified, but the specific size of these RUs may be reduced or expanded. Accordingly, in the present disclosure, the specific size of each RU (i.e., the number of corresponding tones) is not limited and is exemplary. Furthermore, in the present disclosure, within a predetermined bandwidth (e.g., 20, 40, 80, 160, 320 MHz, ...), the number of RUs may vary depending on the RU size. In the example of FIG. 9 and / or FIG. 10 described below, the size and / or number of RUs may be changed, which is the same as in the example of FIG. 8.

[0135] FIG. 9 is a diagram showing an exemplary arrangement of resource units (RU) used in the 40 MHz band.

[0136] Just as various sizes of RUs were used in the example of FIG. 8, 26-RU, 52-RU, 106-RU, 242-RU, 484-RU, etc., may also be used in the example of FIG. 9. Additionally, 5 DC tones may be inserted at the center frequency, 12 tones may be used as guard bands in the leftmost band of the 40 MHz band, and 11 tones may be used as guard bands in the rightmost band of the 40 MHz band.

[0137] In addition, as described, when used for a single user, the 484-RU can be used.

[0138] FIG. 10 is a diagram showing an exemplary arrangement of resource units (RU) used in the 80 MHz band.

[0139] Just as various sizes of RUs were used in the examples of FIGS. 8 and 9, 26-RU, 52-RU, 106-RU, 242-RU, 484-RU, 996-RU, etc., may also be used in the example of FIG. 10. Additionally, in the case of an 80MHz PPDU, the RU arrangement of the HE PPDU and the EHT PPDU may differ, and the example of FIG. 10 shows an example of the RU arrangement for an 80MHz EHT PPDU. In the example of FIG. 10, 12 tones are used as guard bands in the leftmost band of the 80MHz band, and 11 tones are used as guard bands in the rightmost band of the 80MHz band, which is the same for the HE PPDU and the EHT PPDU. Unlike the HE PPDU, where 7 DC tones are inserted into the DC band and there is one 26-RU corresponding to 13 tones on each side of the DC band, the EHT PPDU has 23 DC tones inserted into the DC band and one 26-RU on each side of the DC band. Unlike the HE PPDU, where there is one null subcarrier between 242-RUs outside the center band, there are 5 null subcarriers in the EHT PPDU. In the HE PPDU, one 484-RU does not contain a null subcarrier, but in the EHT PPDU, one 484-RU contains 5 null subcarriers.

[0140] In addition, as described, when used for a single user, the 996-RU can be used, and in this case, the insertion of 5 DC tones is common to both the HE PPDU and the EHT PPDU.

[0141] EHT PPDUs of 160 MHz or higher can be configured as multiple 80 MHz subblocks of FIG. 10. The RU arrangement for each 80 MHz subblock may be the same as the RU arrangement of the 80 MHz EHT PPDU of FIG. 10. When the 80 MHz subblock of a 160 MHz or 320 MHz EHT PPDU is not punctured and the entire 80 MHz subblock is used as part of an RU or MRU (Multiple RU), the 80 MHz subblock may use the 996-RU of FIG. 10.

[0142] Here, an MRU corresponds to a group of subcarriers (or tons) composed of multiple RUs, wherein the multiple RUs constituting the MRU may be RUs of the same size or RUs of different sizes. For example, a single MRU may be defined as 52+26-tons, 106+26-tons, 484+242-tons, 996+484-tons, 996+484+242-tons, 2×996+484-tons, 3×996-tons, or 3×996+484-tons. Here, the multiple RUs constituting a single MRU may correspond to RUs of small size (e.g., 26, 52, 106) or RUs of large size (e.g., 242, 484, 996, etc.). That is, a single MRU containing both small-size RUs and large-size RUs may not be set / defined. In addition, multiple RUs constituting a single MRU may be continuous or non-continuous in the frequency domain.

[0143] If the 80 MHz subblock contains RUs smaller than 996 ton, or if parts of the 80 MHz subblock are punctured, the 80 MHz subblock may use RU batches excluding the 996-ton RU.

[0144] The RU of the present disclosure may be used for uplink (UL) and / or downlink (DL) communication. For example, when trigger-based UL-MU communication is performed, the STA transmitting the trigger (e.g., AP) may assign a first RU (e.g., 26 / 52 / 106 / 242-RU, etc.) to a first STA and assign a second RU (e.g., 26 / 52 / 106 / 242-RU, etc.) to a second STA through trigger information (e.g., a trigger frame or TRS (triggered response scheduling)). Subsequently, the first STA may transmit a first trigger-based (TB) PPDU based on the first RU, and the second STA may transmit a second TB PPDU based on the second RU. The first and second TB PPDUs may be transmitted to the AP in the same time interval.

[0145] For example, when a DL MU PPDU is configured, the STA (e.g., AP) transmitting the DL MU PPDU may allocate a first RU (e.g., 26 / 52 / 106 / 242-RU, etc.) to the first STA and a second RU (e.g., 26 / 52 / 106 / 242-RU, etc.) to the second STA. That is, within a single MU PPDU, the transmitting STA (e.g., AP) may transmit X-STF (e.g., X is HE, EHT, etc.), X-LTF, and Data fields for the first STA through the first RU, and transmit X-STF, X-LTF, and Data fields for the second STA through the second RU. Information regarding the allocation of RUs may be signaled through the X-SIG (e.g., X is HE, EHT, U) field of the X-PPDU format.

[0146] Distributed resource units

[0147] Due to regulations in various regions, limitations on power spectral density (PSD) may be applied in the sub-7GHz (e.g., 6GHz) band. For a non-AP STA in the low-power indoor (LPI) band, the PSD limit may be -1dBm / MHz. For example, for a standard 52-tone RU, the maximum transmit (Tx) power may be approximately 6dBm.

[0148] In addition, different restrictions may apply to the 2.4GHz and 5GHz bands. For example, in the EU, China, Japan, and Korea, a PSD limit of 10dBm / MHz may apply to the 2.4GHz band. For an existing 52-tone RU, this means the maximum Tx power could be approximately 17dBm. If the PSD limit can be bypassed in the 5GHz band, the transmit power can be increased. For example, for an existing 52-tone RU, the maximum transmit power is 24dBm, which is still 6dBm below the maximum allowable EIRP (effective isotropic radiated power) of 30dBm.

[0149] If PSD limitations are overcome, transmit power can be increased, thereby enhancing spectrum efficiency or extending the range.

[0150] Considering that the PSD limit is defined per MHz for each STA, when tones of small-sized RUs are distributed over a wide bandwidth, the tones for each STA are non-contiguous, so each tone can be transmitted at high power. A RU containing such distributed tones is called a distributed RU (DRU), and to distinguish it from this, a RU containing continuous tones defined in existing wireless LAN systems (e.g., systems conforming to IEEE 802.11ax, 11be, etc.) can be called a regular RU (RRU).

[0151] Compared to a conventional STA transmitting an RRU, a STA transmitting a DRU can use higher power. For example, a 52-tone DRU spanning 80 MHz has only one tone per MHz, whereas a 52-tone RRU has approximately 13 tones per MHz. Assuming a PSD limit of -1 dBm / MHz in the 6 GHz LPI band, using a DRU can increase transmit power by approximately 11 dB compared to a 52-tone RU. Increasing transmit power in this way allows for the application of a higher MCS and supports a longer range.

[0152] FIG. 11 is a drawing for illustrating examples of DRUs to which the present disclosure may be applied.

[0153] The example in FIG. 11 illustrates a case where STA1 transmits on DRU1, STA2 transmits on DRU2, and STA3 transmits on DRU3. Each STA can have a transmit power boost applied by using a DRU. Compared to using an RRU of the same size, higher transmit power is applied to all tones in the DRU, and thus spectral efficiency can be significantly improved. As such, the DRU can be particularly useful in UL-OFDMA.

[0154] DRUs can also be utilized in the case of APs. In some cases, APs can perform DL-OFDMA transmission to STA(s) using only some of DRU1, DRU2, and DRU3, in which case a transmit power boost due to the use of DRUs may be applied.

[0155] To maximize power boost, tones within a single DRU can be dispersed as far apart as possible. For example, a DRU containing 1 ton per MHz can be considered an optimal example. The size of a DRU (or the number of available tones included in a single DRU, i.e., the number of remaining tones excluding unusable tones such as null tones, guard tones, and DC tones) can be defined as equal to the size of an RRU (or the number of available tones included in a single RRU). Accordingly, the impact on various technologies previously defined based on RRUs can be minimized. The table below shows examples of achievable power boosts (in dB) for various DRUs distributed across different bandwidths. The examples in the table below assume the 6 GHz LPI band, but power boosts can also be obtained in the 2.4 GHz and 5 GHz bands in other regions. For example, in an 80 MHz UL-OFDMA transmission by 8 users, if each user uses a 106-tone DRU, overall performance can be improved by approximately 8.13 dB compared to when each user uses a 106-tone RRU. In this way, utilizing DRUs can overcome PSD limitations and yield significant gains.

[0156] 20MHz Bandwidth 40MHz Bandwidth 80MHz Bandwidth 26-ton RU8.1311.1411.1452-ton RU6.378.1311.14106-ton RU3.366.378.13242-ton RU Not Applied 2.695.12484-ton RU Not Applied Not Applied 2.69

[0157] Trigger Frame

[0158] FIG. 12 is a drawing showing an exemplary format of a trigger frame to which the present disclosure can be applied.

[0159] A trigger frame may allocate resources for one or more TB PPDU transmissions and request TB PPDU transmissions. The trigger frame may also include other information required by an STA that transmits a TB PPDU in response. The trigger frame may include common info and user info list fields in the frame body.

[0160] The common information field may include information that applies commonly to one or more TB PPDU transmissions requested by a trigger frame, such as trigger type, UL length, whether a subsequent trigger frame exists (e.g., More TF), whether a CS (channel sensing) is required, UL BW (bandwidth), DRU / RRU indication, etc. FIG. 12 illustrates an exemplary format for the common information field of a UHR variant.

[0161] The 4-bit trigger type subfield can have values ​​from 0 to 15. Among these, the values ​​0, 1, 2, 3, 4, 5, 6, and 7 of the trigger type subfield are defined to correspond to basic, BFRP (Beamforming Report Poll), MU-BAR (multi-user-block acknowledgement request), MU-RTS (multi-user-request to send), BSRP (Buffer Status Report Poll), GCR (groupcast with retries) MU-BAR, BQRP (Bandwidth Query Report Poll), and NFRP (NDP Feedback Report Poll), respectively, and the values ​​8 to 15 are defined as reserved.

[0162] The DRU / RRU indication subfield indicates whether a distributed RU (DRU) or regular RU (RRU) transmission is requested in each 80 MHz frequency subblock. The indication by the DRU / RRU indication subfield can be configured in units of 80 MHz frequency subblocks. For example, if the DRU / RRU indication subblock format is composed of 4 bits (B0, B1, B2, B3), B0 can be used for the DRU / RRU indication for the lowest 80 MHz frequency subblock, B1 can be used for the DRU / RRU indication for the second lowest 80 MHz frequency subblock, B2 can be used for the DRU / RRU indication for the second highest 80 MHz frequency subblock, and B3 can be used for the DRU / RRU indication for the highest 80 MHz frequency subblock. If the UL BW is 20 MHz, 40 MHz, or 80 MHz, B1-B3 of the DRU / RRU Indication subfield may be reserved. If the UL BW is 160 MHz, B2-B3 of the DRU / RRU Indication subfield may be reserved. To request a UHR TB PPDU using DRU transmission in the 80 MHz frequency subblock, the corresponding bits of the DRU / RRU Indication subfield are set to 0, otherwise they may be set to 1.

[0163] Among the common information, the trigger-dependent common info subfield may include information that is optionally included based on the trigger type.

[0164] A special user info field may be included within the trigger frame. The special user info field does not contain user-specific information, but rather contains extended common information not provided in the common information field.

[0165] The user information list includes zero or more user info fields. Figure 12 illustrates an exemplary UHR variant user info field format.

[0166] The AID12 subfield basically indicates that it is a user information field for the STA with the corresponding AID. Additionally, if the AID12 field has a specific predetermined value, it may be utilized for other purposes, such as assigning a Random Access (RA)-RU or being configured as a special user info field. A special user info field is a user information field that does not contain user-specific information but includes extended common information not provided in the common information field. For example, a special user info field can be identified by an AID12 value of 2007, and a special user info field flag subfield within the common information field can indicate whether the special user info field is included.

[0167] The RU allocation subfield may indicate the size and location of the RU / MRU. To this end, the RU allocation subfield may be interpreted together with the PS160 (primary / secondary 160MHz) subfield of the user information field, the UL BW extension subfield of the special user information field, the UL BW subfield of the common information field, etc. Additionally, if the RU allocated in the RU allocation of the user information field is located in an 80MHz frequency subblock where the corresponding bit in the DRU / RRU indication subfield of the UHR variant common information field is set to 1, or is located in two or more 80MHz frequency subblocks where the corresponding bits in the DRU / RRU indication subfield of the UHR variant common information field are all set to 1, the allocated RU may be an RRU or an MRU.

[0168] For example, as shown in Table 2 below, the mapping of B7-B1 of the RU allocation subfield can be defined along with the settings of B0 and PS160 subfields of the RU allocation subfield. Table 2 shows an example of the encoding of the PS160 subfield and the RU allocation subfield of the UHR variant user information field.

[0169]

[0170]

[0171] If B0 of the RU allocation subfield is set to 0, it indicates that the RU / MRU allocation is applied to the primary 80MHz channel, and if the value is set to 1, it indicates that the RU allocation is applied to the secondary 80MHz channel of the primary 160MHz. If B0 of the RU allocation subfield is set to 0, it indicates that the RU / MRU allocation is applied to the lower 80MHz of the secondary 160MHz, and if the value is set to 1, it indicates that the RU allocation is applied to the upper 80MHz of the secondary 160MHz.

[0172] In the trigger frame RU allocation table of Table 2, the parameter N can be calculated based on the formula N=2*X1+X0. For bandwidths of 80 MHz or less, the values ​​of PS160, B0, X0, and X1 can be set to 0. For 160 MHz and 320 MHz bandwidths, the values ​​of PS160, B0, X0, and X1 can be set as shown in Table 3. These settings represent the absolute frequency order for the primary and secondary 80 MHz and 160 MHz channels. The order from left to right indicates the order from lowest to highest frequency. The primary 80 MHz channel is designated as P80, the secondary 80 MHz channel as S80, and the secondary 160 MHz channel as S160.

[0173]

[0174] In addition, as shown in Tables 4 to 6, for 20 MHz distributed bandwidth (distributed BW, DBW), 40 MHz DBW, and 80 MHz DBW, mapping of B7-B1 of the RU allocation subfield can be defined along with the settings of B0 and PS160 of the RU allocation subfield.

[0175] Table 4 shows an example of the encoding of the PS160 subfield and RU allocation subfield of the UHR variant user information field for 20MHz DBW.

[0176]

[0177] Table 5 shows an example of the encoding of the PS160 subfield and RU allocation subfield of the UHR variant user information field for 40MHz DBW.

[0178]

[0179] Table 6 shows an example of the encoding of the PS160 subfield and RU assignment subfield of the UHR variant user information field for 80MHz DBW.

[0180]

[0181] The SS allocation subfield can be configured differently depending on whether the subfield is associated with RRU or DRU.

[0182] For example, the SS allocation subfield of the UHR variant user information field associated with the RRU may include a starting spatial stream subfield and a number of spatial streams subfield. As another example, the SS allocation subfield of the UHR variant user information field associated with the DRU may include a DRU distributed bandwidth (DBW) subfield and a number of spatial streams subfield. In other words, the corresponding SS allocation subfield may indicate the DRU DBW and spatial streams of the requested UHR TB PPDU. The DRU DBW subfield indicates the DBW of the allocated DRU, and if the DRU DBW subfield is composed of 2 bits, values ​​from 0 to 3 may be defined for 20 MHz DBW, 40 MHz DBW, 80 MHz DBW, and 60 MHz DBW.

[0183] DRU tone plan-based transmission and reception

[0184] As mentioned above, in order to overcome PSD limitations and improve power gain, a DRU using distributed tone / subcarriers can be applied instead of an RRU using continuous tone / subcarriers.

[0185] In this regard, the aforementioned DRU-based transmission may also be applied to trigger frame (or control frame such as RTS, CTS, etc.)-based transmission. A trigger frame (TF) (or control frame such as RTS, CTS, etc.) transmitted from the AP to the STA(s) may include information indicating a DRU assigned to a specific STA. A specific STA may transmit a trigger-based PPDU (TB PPDU) on the DRU assigned to it. The TB PPDU may include one or more of L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, UHR-SIG, UHR-STF, UHR-LTF, and a Data field. Here, the UHR-LTF field and the Data field may be transmitted on the tone / subcarrier included in the DRU assigned to the STA in the TB PPDU.

[0186] A mapping / correspondence relationship between DRU and RRU may be predefined, or configuration information regarding the mapping / correspondence relationship between DRU and RRU may be provided from AP to STA.

[0187] As another example, the application of DRU can be set on a PPDU basis. Additionally, the STA can transmit one or more PPDUs, and can transmit multiple PPDUs by integrating them in the frequency domain or by configuring them into an aggregated PPDU (A-PPDU) integrated in the time domain. Through control frames (e.g., trigger frames, RTS frames, CTS frames, etc.), the STA can be informed of the application of DRU and bandwidth of one or more PPDUs transmitted to a specific channel, or the STA can be informed of the application of DRU and bandwidth of one or more PPDUs to be transmitted (or received) to the channel through which the control frame is transmitted.

[0188] In addition, the relative position of the pilot tone / subcarrier of the data field applied in a specific RRU (e.g., which tone / subcarrier among all tones / subcarriers in the RRU) may be the same as the relative position of the pilot tone / subcarrier in the DRU corresponding to the specific RRU in the TB PPDU.

[0189] In addition, regarding DRU-based transmission in the aforementioned TB PPDU, a trigger frame (or a control frame such as an RTS or CTS) may include information related to DRU transmission. For example, information related to DRU transmission may include information indicating whether DRU or RRU is applied (e.g., a DRU / RRU indication subfield). Such information may be defined as a 1-bit size, or may be defined as a bitmap having a length corresponding to a predetermined channel size. One bit of the bitmap may correspond to an 80 MHz channel, and the bit value at each bit position may indicate whether DRU or RRU is applied to the corresponding 80 MHz channel.

[0190] A predetermined channel size corresponding to the bitmap length may correspond to the maximum channel size to which the DRU is applicable. If the bandwidth of the TB PPDU is greater than the predetermined channel size, multiple bitmaps may be included in the trigger frame (or control frames such as RTS, CTS, etc.). Accordingly, the maximum channel size to which the DRU is applicable may be identified (or implicitly indicated) based on the bitmap length and / or number. Alternatively, information regarding the predetermined channel size (or the maximum channel size to which the DRU is applicable) may be explicitly included in the trigger frame (or control frames such as RTS, CTS, etc.). Additionally, the trigger frame may include information indicating the channel size to which the DRU is applied. In this regard, information regarding the allocation of the DRU, whether the DRU is applied, channel size information, etc., may be indicated based on specific values ​​of fields in the trigger frame or combinations of each value.

[0191] The size of the channel in which the DRUs are distributed can be referred to as distributed bandwidth (DBW). For example, distributed bandwidths such as 20 MHz DBW, 40 MHz DBW, 60 MHz DBW, 80 MHz DBW, and 160 MHz DBW can be defined, and basically, the corresponding DRU tone plan can be defined within a bandwidth of the same size.

[0192] In this regard, when transmitting PPDU of 80 MHz or higher, DRU transmission may be applied when one 20 MHz channel is punctured in a specific 80 MHz frequency subblock (or specific 80 MHz channel), and in particular, when the 20 MHz channel of the highest frequency is punctured, DRU transmission with a 60 MHz DBW may be defined. For the DRU transmission with the 60 MHz DBW, a 60 MHz DRU tone plan may be applied.

[0193] The present disclosure proposes a method for constructing UHR-STF when transmitting a 60MHz DBW, that is, when transmitting a DRU with a 60MHz DBW. In other words, when transmitting a DRU with a 60MHz DWB, a method for constructing a UHR-STF portion within the corresponding TB PPDU (e.g., a UHR-STF field, tones modulated to construct the UHR-STF field) and a method for defining a sequence applied to the corresponding UHR-STF portion are specifically described.

[0194] Additionally or alternatively, when transmitting a PPDU of 80 MHz or higher, a DRU transmission may be applied if a specific 20 MHz channel is punctured in a specific 80 MHz frequency subblock (or a specific 80 MHz channel), and such DRU transmission may be defined as a DRU transmission having a 60 MHz DBW. For example, the specific 20 MHz channel may correspond to one of the lowest 20 MHz channel, the second lowest 20 MHz channel, the second highest 20 MHz channel, or the highest 20 MHz channel in terms of the frequency domain within the 80 MHz frequency subblock. The UHR-STF configuration method proposed in this disclosure may include the UHR-STF configuration method during such DRU transmission.

[0195] Specifically, the aforementioned transmission may be a UL TB PPDU transmission, and in such a transmission situation, the UHR-STF applied to an 80 MHz frequency subblock (or 80 MHz channel) in which a 20 MHz channel is punctured (i.e., unused, unassigned) may be configured / defined as follows.

[0196] First, regarding the UHR-STF sequence to be used in the UHR-STF section, an 80 MHz 2x UHR-STF sequence may be applied. For example, the 80 MHz 2x UHR-STF sequence may be identical to the existing 80 MHz 2x EHT-STF sequence. Alternatively, regarding the UHR-STF sequence to be used in the UHR-STF section, a 2x UHR-STF sequence defined in the PPDU bandwidth (e.g., bandwidth for the TB PPDU) may be applied. In other words, the UHR-STF sequence applied to an 80 MHz frequency subblock where the 20 MHz channel is punctured (i.e., unused, unassigned) may be determined based on the PPDU bandwidth.

[0197] In addition, regarding the tone configuration / modulation of the UHR-STF portion, the UHR-STF portion (e.g., UHR-STF field) applied to an 80MHz frequency subblock where the 20MHz channel is punctured (i.e., unused, unassigned) can be configured in the same way as in the situation where the highest 20MHz channel or a specific punctured 20MHz channel is unused in an 80MHz UL TB PPDU transmission, and a 484+242-tone RRU / MRU is transmitted. In other words, the UHR-STF tones modulated during a DRU transmission with a 60MHz DBW in an 80MHz frequency subblock where the 20MHz channel is punctured (i.e. unused, unassigned) can be the same as the UHR-STF tones modulated in the situation where the aforementioned 484+242-tone RRU / MRU is transmitted.

[0198] In this regard, when a 2x UHR-STF sequence defined in the PPDU bandwidth is applied / used, the UHR-STF portion can be configured in the same way as a situation in which the highest 20MHz channel or a specific punctured 20MHz channel in the corresponding 80MHz frequency subblock is not used to transmit 484+242-tone RRU / MRU.

[0199] In addition, regarding the application of cyclic shift diversity (CSD) to UHR-STF, a specific CSD may be applied depending on the DRU used for the transmission.

[0200] In the following, we propose a specific method for selecting, determining, applying, and defining a measured CSD value (e.g., CSD index value) that can be applied according to the DRU. The proposed CSD value can be applied to any DRU(s) available for 60 MHz DBW transmission, regardless of the location of the punctured 20 MHz channel.

[0201] For example, CSD can be defined based on pre-defined CSD values ​​as shown in Table 7 and / or Table 8 below.

[0202] Table 7 shows cyclic shift values ​​for VHT modulated fields of PPDU that can be applied to the present disclosure.

[0203] T_CS,VHT (n) values ​​for the VHT modulated fields of a PPDUTotal number of space-time streams(N_STS,total)Cyclic shift for space-time stream n (ns)1234567810-------20-400------30-400-200-----40-400-200-600----50-400-200-600-350 ---60-400-200-600-350-650--70-400-200-600-350-650-100-80-400-200-600-350-650-100-750

[0204] Table 8 shows the cyclic shift values ​​for the L-STF, L-LTF, L-SIG, and VHT-SIG-A fields of the PPDU that can be applied to the present disclosure.

[0205] T_CS^iTX values ​​for L-SFT, L-LTF, L-SIG, and VHT-SIG-A fields of the PPDUTotal number of transmit chains (N_TX) per frequency segmentCyclic shift for transmit chain iTX (in units of ns)12345678>810------20-200-----30-100-200----40-50-100-150---50-175-25-50-75--60-200-25-150-175 -125-70-200-150-25-175-75-5080-175-150-125-25-100-50-200>80-175-150-125-25-100-50-100Between-200 and 0

[0206] The global CSD start index (or CSD start index) described in this disclosure may correspond to the cyclic shift for space-time stream n value in Table 7 or the cyclic shift for transmit chain iTX value in Table 8.

[0207] For a DRU where multi-stream transmission is applied, the global CSD start index for each stream can be defined based on the formula mod(i-1:i+Nss-2,8)+ones(1,Nss). In the formula, mod(a:b,c) represents a modulo operation that calculates the remainder when divided by c for each value in the range from a to b, i represents the CSD start index for the DRU, and ones(1,Nss) represents a vector consisting of Nss 1s.

[0208] For example, if up to 2 spatial streams are applicable for a DRU transfer, and the global CSD start index is denoted as i, the mod(i-1,8)+1th CSD value may be applied to the first stream (i.e., the i-th), and the mod(i,8)+1th CSD value may be applied to the second stream.

[0209] The aforementioned method of applying CSD values ​​(e.g., mod(i-1:i+NSS-2,8)+1 or mod(i-1:i+Nss-2,8)+ones(1,Nss)) can be applied in the same way not only to 60MHz DBW but also to 20 / 40 / 80MHz DBW.

[0210] In the following, specific examples are described for defining the global CSD start index (hereinafter referred to as the CSD start index for convenience of explanation) applied to each DRU in the 60 MHz DBW considered in the present disclosure (e.g., a 60 MHz DBW where the highest 20 MHz channel in an 80 MHz frequency subblock is punctured / unused / unassigned).

[0211] Example 1

[0212] Table 9 shows an example of the CSD start index definitions by DRU index at 60MHz DBW.

[0213] DRU Size CSD Starting Index for 60MHz DBW DRU 26, i=1:28{1,5,2,6,a,3,7,4,8,1,5,2,6,b,3,7,4,8,-,1,5,2,6,c,3,7,4,8}DRU 52, i=1:12{1,2,3,4,5,6,7,8,1,2,3,4}DRU 106, i=1:6{2,4,6,8,2,4} or {1,3,5,7,1,3}DRU 242, i=1:3{3, 7 or 5, 1} or {1, 5 or 7, 3} or {4, 8 or 6, 2} or {2, 6 or 8, 4}

[0214] Referring to Table 9, similar to how the 26-ton RU 19 is not defined in the existing RRU ton plan, the 19th 26-ton DRU may not be defined. This may be to reuse the existing RU allocation method by making the RU index of the RRU and DRU identical. Therefore, the CSD starting index value applied to the 19th 26-ton DRU may not be defined.

[0215] The 1st through 4th, 10th through 13th, and 20th through 23rd 26-ton DRUs may use CSD starting indices of {1, 5, 2, 6}. The 6th through 9th, 15th through 18th, and 25th through 28th 26-ton DRUs may use CSD starting indices of {3, 7, 4, 8}.

[0216] The 5th, 14th, and 24th 26-ton DRUs may use CSD starting indices of {3,7 or 5,1}, or {1,5 or 7,3}, or {4,8 or 6,2}, or {2,6 or 8,4} (e.g., values ​​a, b, and c in Table 9). Additionally, or alternatively, the 5th, 14th, and 24th 26-ton DRUs may be identical to the CSD starting indices of the 1st, 2nd, and 3rd 242-ton DRUs (e.g., values ​​a, b, and c in Table 9).

[0217] The 1st to 4th, 5th to 8th, and 9th to 12th 52-ton DRUs may use CSD starting indices of {1, 2, 3, 4}, or {5, 6, 7, 8}.

[0218] The 1st and 2nd, 3rd and 4th, and 5th and 6th 106-ton DRUs can use CSD starting indices of {1, 3}, or {2, 4}, or {5, 7}, or {6, 8}.

[0219] The 1st to 3rd 242-ton DRUs may use CSD starting indices of {3, 7 or 5, 1 or 5}, or {1, 5 or 7, 3 or 7}, or {4, 8 or 6, 2 or 6}, or {2, 6 or 8, 4 or 8}.

[0220] Additionally, for a 60 MHz DBW, a 484-ton DRU can be defined by combining two specific 242-ton DRUs. In this case, the 484-ton DRU may use a CSD starting index of {3, or 7, or 5, or 1}, or alternatively, the 484-ton DRU may use a CSD index of {4, or 8, or 6, or 2}.

[0221] Example 2

[0222] Table 10 shows another example of CSD start index definitions by DRU index at 60MHz DBW.

[0223] DRU Size CSD Starting Index for 60MHz DBW DRU 52, i=1:12{1,5,2,6,3,7,4,8,1,5,2,6} or {1,5,2,6,3,7,4,8,3,7,4,8}DRU 106, i=1:6{1,2,3,4,5,6} or {1,2,3,4,7,8}DRU 242, i=1:3{2,4,6} or {1,3,5} or {2,4,8} or {1,3,7}

[0224] The example in Table 10 is for the CSD starting index applied to each DRU in the case where a 26-tone DRU may not be defined in a 60 MHz DRU tone plan and is defined starting from a 52-tone DRU.

[0225] Additionally, for a 60 MHz DBW, a 484-ton DRU can be defined by combining two specific 242-ton DRUs. In this case, the 484-ton DRU may use a CSD starting index of {3, or 7, or 5, or 1}, or alternatively, the 484-ton DRU may use a CSD index of {4, or 8, or 6, or 2}.

[0226] Example 3

[0227] Table 11 shows another example of CSD start index definitions by DRU index at 80MHz DBW.

[0228] DRU Size CSD Starting Index for 60MHz DBW DRU 52, i=1:16{1,5,2,6,3,7,4,8,1,5,2,6,3,7,4,8}DRU 106, i=1:8{1,2,3,4,5,6,7,8}DRU 242, i=1:4{2,4,6,8}DRU 484, i=1:2{3,7}

[0229] For the 60MHz DRU tone plan, the CSD start index defined as in Table 11 can be applied as is. In other words, the CSD start index defined in the 80MHz DRU, which is identical to the index of the DRU defined in 60MHz, can be used. However, this example applies only when the 26-tone DRU is not defined in the 60MHz tone plan and is defined starting from the 52-tone DRU.

[0230] Example 4

[0231] Additionally or alternatively, examples may be considered in which some DRUs use the proposed (or defined in 80 MHz DBW) CSD start index in a situation where the 26-ton DRU is not considered, and some use the proposed CSD start index (e.g., Example 1 in Table 9) in consideration of the case where the aforementioned 26-ton DRU is used.

[0232] For example, the 1st to 8th 52-ton DRUs, the 1st to 4th 106-ton DRUs, and the 1st and 2nd 242-ton DRUs use the proposed (or defined in 80MHz DBW) CSD start index in a situation where the 26-ton DRU is not considered, and the 9th to 12th 52-ton DRUs, the 5th and 6th 106-ton DRUs, and the 3rd 242-ton DRU may use the proposed CSD start index in a case where the 26-ton DRU is used. As a specific example, the 9th to 12th 52-ton DRUs may use the CSD start index of {5, 6, 7, 8}, the 5th and 6th 106-ton DRUs may use the CSD start index of {6, 8}, and the 3rd 242-ton DRU may use the CSD start index of {7}.

[0233] Example 5

[0234] Table 12 shows another example of CSD start index definitions by DRU index at 60MHz DBW.

[0235] DRU Size CSD Starting Index for 60MHz DBW DRU 52, i=1:12{1,7,2,8,3,7,4,8,1,5,2,6}DRU 106, i=1:6{1,2,3,4,5,6}DRU 242, i=1:3{2,4,6}

[0236] The example in Table 12 is about a method to minimize CSD start index conflicts between DRUs while reusing the CSD start index defined in the 80MHz DBW as much as possible.

[0237] Referring to Table 12, in the CSD start indices defined in the 80MHz DBW, only the CSD start indices of the 2nd 52-ton DRU and the 4th 52-ton DRU can be converted to {7} and {8}. Alternatively, the CSD start index {8} may be used for the 2nd 52-ton DRU and the CSD start index {7} may be used for the 4th 52-ton DRU. Through this, conflicts in the CSD start indices can be minimized.

[0238] Additionally, for the first 242-ton DRU, instead of CSD start index {2}, CSD start index {1, or 7, or 8} may be used. In this case, conversion of the CSD start indices of the second 52-ton DRU, the fourth 52-ton DRU, and the first 242-ton DRU from the CSD start indices defined in the 80MHz DBW may be required, but the frequency of collisions between the CSD start index of the 11th 52-ton DRU and the CSD start indices of the 106-ton DRU and the 242-ton DRU may be reduced.

[0239] Example 6

[0240] Table 13 shows another example of CSD start index definitions by DRU index at 60MHz DBW.

[0241] DRU Size CSD Starting Index for 60MHz DBW DRU 52, i=1:12{1,5,2,6,3,7,4,8,7,5,8,6}DRU 106, i=1:6{1,2,3,4,5,6}DRU 242, i=1:3{2,4,6}

[0242] The example in Table 13 is about another method to minimize CSD start index conflicts between DRUs while reusing the CSD start index defined in the 80MHz DBW as much as possible.

[0243] Referring to Table 13, in the CSD start indices defined in the 80MHz DBW, only the CSD start indices of the 9th 52-ton DRU and the 11th 52-ton DRU can be converted to {7} and {8}. Alternatively, the CSD start index {8} may be used for the 9th 52-ton DRU and the CSD start index {7} may be used for the 11th 52-ton DRU. This minimizes conflicts in the CSD start indices.

[0244] Additionally, for the 3rd 242-ton DRU, instead of CSD start index {6}, CSD start index {5, or 7, or 8} may be used. In this case, conversion of the CSD start indices of the 9th 52-ton DRU, 11th 52-ton DRU, and 3rd 242-ton DRU from the CSD start indices defined in the 80MHz DBW may be required, but the frequency of collisions between the CSD start index of the 4th 52-ton DRU and the CSD start indices of the 106-ton DRU and 242-ton DRU may be reduced.

[0245] Example 7

[0246] Table 14 shows another example of CSD start index definitions by DRU index at 60MHz DBW.

[0247] DRU Size CSD Starting Index for 60MHz DBW DRU 52, i=1:12{1,5,2,7,3,7,4,8,1,5,3,6}DRU 106, i=1:6{1,2,3,4,5,6}DRU 242, i=1:3{2,4,6}

[0248] The example in Table 14 is about another method to minimize CSD start index conflicts between DRUs while reusing the CSD start index defined in the 80MHz DBW as much as possible.

[0249] Referring to Table 14, only the CSD start indices of the 4th 52-ton DRU and the 11th 52-ton DRU defined in the 80 MHz DBW can be converted to {7} and {3}. This minimizes the collision of CSD start indices. In particular, good performance can be maintained even in multi-stream situations, as there can be up to 3 DRUs with CSD collisions even when considering multiple streams (e.g., 2 spatial streams).

[0250] Example 8

[0251] Table 15 shows another example of CSD start index definitions by DRU index at 60MHz DBW.

[0252] DRU Size CSD Starting Index for 60MHz DBW DRU 52, i=1:12{1,5,2,3,3,7,4,8,1,5,7,6}DRU 106, i=1:6{1,2,3,4,5,6}DRU 242, i=1:3{2,4,6}

[0253] The example in Table 15 is about another method to minimize CSD start index conflicts between DRUs while reusing the CSD start index defined in the 80MHz DBW as much as possible.

[0254] Referring to Table 15, only the CSD start indices of the 4th 52-ton DRU and the 11th 52-ton DRU defined in the 80 MHz DBW can be converted to {3} and {7}. This minimizes the collision of CSD start indices. In particular, good performance can be maintained even in multi-stream situations, as there can be up to 3 DRUs with CSD collisions even when considering multiple streams (e.g., 2 spatial streams).

[0255] Hereinafter, STA operations based on the various methods and examples of the present disclosure described above are described with reference to FIGS. 13 and 14. The examples of FIGS. 13 and 14 may correspond to some of the various examples of the present disclosure.

[0256] For example, in FIGS. 13 and 14, the first STA corresponds to a non-AP STA that receives a trigger frame requesting (solicit) a TB PPDU, and the second STA corresponds to an AP that transmits the trigger frame. Here, the non-AP STA corresponding to the first STA may be a STA coupled to the AP corresponding to the second STA.

[0257] FIG. 13 is a diagram illustrating an example of operation by a first STA in a PPDU transmission and reception method based on a DRU tone plan according to the present disclosure.

[0258] Referring to FIG. 13, the first STA can receive a trigger frame containing information related to a distributed resource unit (DRU) from the second STA (S1310).

[0259] For example, information related to the DRU may include first information regarding whether the DRU or Regular RU (RRU) is applied (e.g., DRU / RRU indication subfield) and second information regarding the distributed bandwidth to which the DRU is applied (e.g., DRU distributed bandwidth indication subfield).

[0260] Here, the first information is included in a common information field within the trigger frame, and the second information may be included in a user information field within the trigger frame. In this regard, the first information may include one or more subfields indicating whether to apply a DRU or an RRU in units of frequency subblocks of a certain size (e.g., 80 MHz). Additionally, the user information field may further include a RU allocation subfield for allocating one or more DRUs within the distributed bandwidth.

[0261] The first STA can transmit a TB PPDU based on the corresponding DRU to the second STA in the bandwidth (S1320).

[0262] In this regard, if the highest 20 MHz channel within an 80 MHz frequency subblock (or 80 MHz channel) included in the bandwidth of the TB PPDU is not used (e.g., if the 20 MHz channel is punctured / not allocated), a 60 MHz distributed bandwidth (DBW) may be applied to the 80 MHz frequency subblock.

[0263] In this case, for transmission based on the 60 MHz distributed bandwidth, the STF portion within the TB PPDU (e.g., UHR-STF field) may be configured based on the STF portion in the case of transmitting 484+242-tone MRU (multiple RU) in an 80 MHz frequency subblock where the highest 20 MHz channel is not used (e.g., in the same way).

[0264] According to the present disclosure, the STF sequence used in the STF portion (e.g., UHR-STF sequence) can be determined based on the bandwidth of the TB PPDU.

[0265] Additionally, according to the present disclosure, a CSD value may be applied to the corresponding STF portion. In this case, the CSD value may be determined based on a CSD start index value mapped to the index of the DRU. In this regard, when 12 52-ton DRUs, 6 106-ton DRUs, and 3 242-ton DRUs are defined for the 60 MHz distributed bandwidth, the CSD start index values ​​for the 12 52-ton DRUs may be defined as {1, 5, 2, 6, 3, 7, 4, 8, 1, 5, 2, 6} in the order of the DRU indices, the CSD start index values ​​for the 6 106-ton DRUs may be defined as {1, 2, 3, 4, 5, 6} in the order of the DRU indices, and the CSD start index values ​​for the 3 106-ton DRUs may be defined as {2, 4, 6} in the order of the DRU indices.

[0266] Additionally, according to the present disclosure, when multiple streams are applied to a DRU, the CSD index value for each stream may be determined by mod(i-1:i+Nss-2,8)+ones(1,Nss). Here, i represents the CSD starting index for the DRU, Nss represents the number of streams for the DRU, mod(a:b,c) represents a modulo operation that calculates the remainder when divided by c for each of the values ​​in the range from a to b, and ones(1,Nss) may represent a vector consisting of Nss 1s.

[0267] The method described in the example of FIG. 13 may be performed by the first device (100) of FIG. 1. For example, one or more processors (102) of the first device (100) of FIG. 1 may be configured to receive a trigger frame containing information related to a DRU through one or more transceivers (106) and to transmit a TB PPDU based on the said DRU. Furthermore, one or more memories (104) of the first device (100) may store instructions for performing the method described in the example of FIG. 13 or the examples described above when executed by one or more processors (102).

[0268] FIG. 14 is a diagram illustrating an example of operation by a second STA in a PPDU transmission and reception method based on a DRU tone plan according to the present disclosure.

[0269] Referring to FIG. 14, the second STA can transmit a trigger frame containing information related to a distributed resource unit (DRU) to the first STA (S1410).

[0270] For example, information related to the DRU may include first information regarding whether the DRU or Regular RU (RRU) is applied (e.g., DRU / RRU indication subfield) and second information regarding the distributed bandwidth to which the DRU is applied (e.g., DRU distributed bandwidth indication subfield).

[0271] Here, the first information is included in a common information field within the trigger frame, and the second information may be included in a user information field within the trigger frame. In this regard, the first information may include one or more subfields indicating whether to apply a DRU or an RRU in units of frequency subblocks of a certain size (e.g., 80 MHz). Additionally, the user information field may further include a RU allocation subfield for allocating one or more DRUs within the distributed bandwidth.

[0272] The second STA can receive a TB PPDU based on the corresponding DRU from the first STA in the bandwidth (S1420).

[0273] In this regard, if the highest 20 MHz channel within an 80 MHz frequency subblock (or 80 MHz channel) included in the bandwidth of the TB PPDU is not used (e.g., if the 20 MHz channel is punctured / not allocated), a 60 MHz distributed bandwidth (DBW) may be applied to the 80 MHz frequency subblock.

[0274] In this case, for transmission based on the 60 MHz distributed bandwidth, the STF portion within the TB PPDU (e.g., UHR-STF field) may be configured based on the STF portion in the case of transmitting 484+242-tone MRU (multiple RU) in an 80 MHz frequency subblock where the highest 20 MHz channel is not used (e.g., in the same way).

[0275] In the example of Fig. 14, specific details regarding the STF sequence for the STF portion, the application of CSD to the STF portion and the related CSD start index value, the formula for determining the CSD index value, the application of tone shift, and signaling of DRU-related information are identical to the explanation in the example of Fig. 13, so redundant explanations are omitted.

[0276] The method described in the example of FIG. 14 may be performed by the second device (200) of FIG. 1. For example, one or more processors (202) of the second device (200) of FIG. 1 may be configured to transmit a trigger frame containing information related to a DRU and to receive a TB PPDU based on the said DRU through one or more transceivers (106). Furthermore, one or more memories (204) of the second device (200) may store instructions for performing the method described in the example of FIG. 14 or the examples described above when executed by one or more processors (202).

[0277] FIG. 15 is a diagram illustrating a PPDU transmission and reception procedure between a transmitting STA and a receiving STA according to one embodiment of the present disclosure. Some of the step(s) shown in FIG. 15 may be omitted depending on the situation and / or settings, etc. The transmitting device and the receiving STA may be an AP and / or a non-AP STA.

[0278] The transmitting STA can obtain control information related to the tone-plan (or RU / DRU) described above (S105). The control information related to the tone-plan may include the size and location of the RU, control information related to the RU, information regarding the frequency band in which the RU is included, information regarding the STA receiving the RU, etc.

[0279] The transmitting STA can configure / generate a PPDU based on acquired control information (S110). Configuring / generating a PPDU may mean configuring / generating each field of the PPDU. That is, the step of configuring / generating a PPDU may include the step of configuring a SIG field (e.g., U-SIG / UHR-SIG) containing control information regarding a tone-plan.

[0280] That is, the step of configuring / generating the PPDU may include the step of configuring a field containing control information (e.g., N bitmap) indicating the size / location of the RU and / or the step of configuring a field containing an identifier (e.g., AID) of the STA receiving the RU.

[0281] Additionally, the step of configuring / generating the PPDU may include the step of generating an STF / LTF sequence transmitted through a specific RU. The STF / LTF sequence may be generated based on a preset STF generation sequence / LTF generation sequence. For example, an LTF portion (e.g., an LTF field) included in the PPDU may be configured based on the UHR-LTF sequence proposed in this disclosure.

[0282] Additionally, the step of configuring / generating the PPDU may include the step of generating a data field (i.e., MPDU) that is transmitted through a specific RU.

[0283] The transmitting STA can transmit the configured / generated PPDU to the receiving STA (S115).

[0284] Specifically, the transmitting STA can perform at least one of cyclic shift diversity (CSD), spatial mapping, inverse discrete Fourier transform (IDFT) / inverse fast Fourier transform (IFFT) operations, and guard interval (GI) insertion operations.

[0285] The receiving STA can decode the PPDU and obtain control information related to the tone-plan (or RU) (S120).

[0286] Specifically, the receiving STA can decode the L-SIG and SIG fields (e.g., U-SIG / UHR-SIG) of the PPDU based on L-STF / LTF and obtain information contained in the L-SIG and SIG fields. Information regarding various tone-plans (i.e., RU) of the present disclosure may be contained in the SIG field (e.g., U-SIG / UHR-SIG), and the receiving STA can obtain information regarding the tone-plan (i.e., RU) through the said SIG field.

[0287] The receiving STA can decode the remainder of the PPDU based on information regarding the acquired tone-plan (i.e., RU) (S125). For example, the receiving STA can decode the STF / LTF portion of the PPDU (e.g., STF / LTF field) based on information regarding the tone-plan (i.e., RU). In particular, the LTF portion may be constructed by the UHR-LTF sequence proposed in this disclosure and may be used for channel estimation for decoding the data portion (e.g., data field).

[0288] In addition, the receiving STA can decode the data field of the PPDU based on information regarding the tone-plan (i.e., RU) and obtain the MPDU contained in the data field.

[0289] In addition, the receiving STA can perform a processing operation to transmit the decoded data to an upper layer (e.g., MAC layer). In addition, if the generation of a signal is instructed from the upper layer to the PHY layer in response to the data transmitted to the upper layer, the receiving STA can perform a subsequent operation.

[0290] In cases where the application of DRU is supported, unlike in existing wireless LAN systems where only RRU is applied, the efficiency of resource utilization can be increased by transmitting / receiving one or more PPDU fields based on various sizes of DRU tone plans applicable to PPDUs with a bandwidth of 20 MHz or more according to the present disclosure.

[0291] The embodiments described above are combinations of the components and features of the present disclosure in a specific form. Each component or feature should be considered optional unless otherwise explicitly stated. Each component or feature may be implemented in a form not combined with other components or features. Additionally, it is possible to construct embodiments of the present disclosure by combining some components and / or features. The order of operations described in the embodiments of the present disclosure may be changed. Some components or features of one embodiment may be included in another embodiment, or may be replaced with corresponding components or features of another embodiment. It is obvious that embodiments may be constructed by combining claims that are not explicitly related in the claims, or that they may be included as new claims by amendment after filing.

[0292] It is obvious to those skilled in the art that the present disclosure may be embodied in other specific forms without departing from the essential features of the present disclosure. Accordingly, the detailed description set forth above should not be interpreted restrictively in all respects and should be considered exemplary. The scope of the present disclosure shall be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the present disclosure are included within the scope of the present disclosure.

[0293] The scope of the present disclosure includes software or machine-executable instructions (e.g., operating systems, applications, firmware, programs, etc.) that enable operations according to the methods of various embodiments to be executed on a device or computer, and a non-transitory computer-readable medium on which such software or instructions, etc. are stored and executable on a device or computer. Instructions that may be used to program a processing system to perform the features described in the present disclosure may be stored on or within a storage medium or a computer-readable storage medium, and the features described in the present disclosure may be implemented using a computer program product comprising such a storage medium. The storage medium may include, but is not limited to, high-speed random access memory such as DRAM, SRAM, DDR RAM, or other random access solid-state memory devices, and may include non-volatile memory such as one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid-state storage devices. The memory may optionally include one or more storage devices located remotely from the processor(s). Memory or alternatively, non-volatile memory device(s) within memory comprises a non-transient computer-readable storage medium. The features described in this disclosure may be stored in any one of the machine-readable media and integrated into software and / or firmware that can control the hardware of a processing system and allow the processing system to interact with other mechanisms utilizing results according to the embodiments of this disclosure. Such software or firmware may include, but is not limited to, application code, device drivers, operating systems, and execution environments / containers.

[0294] Although the method proposed in this disclosure has been described with an example applied to an IEEE 802.11-based system, it can be applied to various wireless LANs or wireless communication systems in addition to IEEE 802.11-based systems.

Claims

1. A step of receiving, by the first station (STA), a trigger frame containing information related to a distributed resource unit (DRU) from the second STA; and The method includes the step of transmitting a trigger-based (TB) PPDU (physical layer protocol data unit) based on the DRU to the second STA by the first STA, wherein Based on the fact that the highest 20MHz channel within the 80MHz frequency subblock included in the bandwidth of the above TB PPDU is not used, a 60MHz distributed bandwidth is applied to the above 80MHz frequency subblock, and A method for transmission based on the above 60 MHz distributed bandwidth, wherein the short training field (STF) portion within the TB PPDU is configured based on the STF portion in the case where 484+242-tone multiple resource units (MRU) are transmitted in an 80 MHz frequency subblock where the highest 20 MHz channel is not used.

2. In Paragraph 1, A method in which the STF sequence used in the above STF portion is determined based on the bandwidth of the above TB PPDU.

3. In Paragraph 1, A CSD (cyclic shift diversity) value is applied to the above STF portion, and A method in which the above CSD value is determined based on the CSD start index value mapped to the index of the above DRU.

4. In Paragraph 3, For the above 60MHz distributed bandwidth, 12 52-ton DRUs, 6 106-ton DRUs, and 3 242-ton DRUs are defined, and The CSD starting index values ​​for the above 12 52-ton DRUs are defined as {1, 5, 2, 6, 3, 7, 4, 8, 1, 5, 2, 6} in the order of the DRU indices, and The CSD starting index values ​​for the above 6 106-ton DRUs are defined as {1, 2, 3, 4, 5, 6} in the order of the DRU indices, and A method in which the CSD starting index values ​​for the three 106-ton DRUs are defined as {2, 4, 6} in the order of the DRU indices.

5. In Paragraph 1, Based on the application of multiple streams to the above DRU, the CSD (cyclic shift diversity) index value for each stream is determined by mod(i-1:i+Nss-2,8)+ones(1,Nss), and Here, i represents the starting index of the CSD for the DRU, Nss represents the number of streams for the DRU, mod(a:b,c) represents a modulo operation that calculates the remainder when divided by c for each value in the range from a to b, and ones(1,Nss) represents a vector consisting of Nss 1s, method.

6. In Paragraph 1, A method comprising information related to the above DRU including first information regarding whether a DRU or a Regular RU (RRU) is applied and second information regarding the distributed bandwidth to which the DRU is applied.

7. In Paragraph 6, The above first information is included in the common information field within the trigger frame, and The above second information is included in the user information field within the trigger frame, a method.

8. In Paragraph 7, A method comprising the above first information including a subfield for indicating whether to apply DRU or RRU in units of frequency subblocks of a certain size.

9. In Paragraph 1, The above-mentioned first STA corresponds to a non-access point (AP) STA, and The above second STA is a method corresponding to an AP combined with the above first STA.

10. One or more transceivers; and It includes one or more processors connected to the above one or more transmitters and receivers, and The above one or more processors are: The first station (STA) receives a trigger frame from the second STA containing information related to a distributed resource unit (DRU); The first STA is configured to transmit a trigger-based (TB) PPDU (physical layer protocol data unit) to the second STA based on the DRU, by the above first STA. Based on the fact that the highest 20MHz channel within the 80MHz frequency subblock included in the bandwidth of the above TB PPDU is not used, a 60MHz distributed bandwidth is applied to the above 80MHz frequency subblock, and A device for a transmission based on the above 60MHz distributed bandwidth, wherein the short training field (STF) portion within the TB PPDU is configured based on the STF portion in the case of transmitting 484+242-tone multiple resource units (MRU) in an 80MHz frequency subblock where the highest 20MHz channel is not used.

11. A step of transmitting a trigger frame containing information related to a distributed resource unit (DRU) to the first STA by the second station (STA); and The method includes the step of receiving a trigger-based (TB) PPDU (physical layer protocol data unit) based on the DRU from the first STA by the second STA, wherein Based on the fact that the highest 20MHz channel within the 80MHz frequency subblock included in the bandwidth of the above TB PPDU is not used, a 60MHz distributed bandwidth is applied to the above 80MHz frequency subblock, and A method for transmission based on the above 60 MHz distributed bandwidth, wherein the short training field (STF) portion within the TB PPDU is configured based on the STF portion in the case where 484+242-tone multiple resource units (MRU) are transmitted in an 80 MHz frequency subblock where the highest 20 MHz channel is not used.

12. One or more transceivers; and It includes one or more processors connected to the above one or more transmitters and receivers, and The above one or more processors are: The second station (STA) transmits a trigger frame containing information related to a distributed resource unit (DRU) to the first STA; The second STA is configured to receive a trigger-based (TB) PPDU (physical layer protocol data unit) based on the DRU from the first STA, wherein Based on the fact that the highest 20MHz channel within the 80MHz frequency subblock included in the bandwidth of the above TB PPDU is not used, a 60MHz distributed bandwidth is applied to the above 80MHz frequency subblock, and A device for a transmission based on the above 60MHz distributed bandwidth, wherein the short training field (STF) portion within the TB PPDU is configured based on the STF portion in the case of transmitting 484+242-tone multiple resource units (MRU) in an 80MHz frequency subblock where the highest 20MHz channel is not used.

13. A processing device configured to control a station (STA) in a wireless local area network (WLAN) system, wherein the processing device: One or more processors; and A processing device comprising one or more computer memories that are operably connected to one or more processors and store instructions for performing a method according to any one of claims 1 to 9 based on execution by one or more processors.

14. One or more non-transitory computer-readable media storing one or more instructions, A computer-readable medium in which one or more of the above commands are executed by one or more processors to control a device in a wireless LAN system to perform a method according to any one of claims 1 through 9.

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