Configuration of training signal for long-range communication

Abstract

The present specification may present a method for transmitting / receiving a physical protocol data unit (PPDU) having an improved structure, and a device related thereto. For example: the physical protocol data unit (PPDU) of the present disclosure can include an LTF and a data field; the data field can be transmitted through four 52-tone resource units (RUs) which are duplicated in a frequency domain in 52-tone RUs; the four 52-tone RUs can include a first RU, a second RU, a third RU and a fourth RU, which are sequentially positioned in the frequency domain; the LTF corresponding to the first RU can be generated on the basis of an LTF sequence; the LTF sequence can include a sequence acquired by multiplying a first sequence including 52 elements by at least one first coefficient; and the first sequence can be {1, 1, 1, 1, -1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1, 1, -1, 1, 1, 1, -1, -1, 1, 1, 1, 1, 1, 1, 1, -1, 1, 1, -1, -1, 1, -1, 1, 1, 1, 1, 1, -1, 1, -1, -1, -1, 1, 1, -1, -1, -1}.

Description

Composition of training signals for long-distance communication

[0001] The present disclosure relates to a wireless LAN system, and more particularly, to a method and apparatus for improving a training field in a wireless LAN system.

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

[0003] For example, a new standard that further improves the EHT standard is called the Ultra High Reliability (UHR) standard. The UHR standard may also be designated as IEEE 802.11bn or Wi-Fi 8. For example, the UHR standard may propose technical features that improve data rates even at low signal-to-interference-plus-noise ratio (SINR) levels. Furthermore, the UHR standard may propose technical features that minimize latency and jitter even in scenarios with mobility and overlapping BSSs. Furthermore, the UHR standard may propose technical features for wireless medium reuse.

[0004] Existing wireless LAN systems have proposed training signals for various purposes. For example, long training fields (LTFs) related to wireless LAN systems have been proposed for channel estimation and MIMO channel estimation.

[0005] There may be several reasons why the signal transmission range in a WLAN system needs to be increased. A WLAN system may operate with various STAs, including access points (APs) and non-AP STAs (stations). Typically, the TX power of an AP is greater than that of a non-AP STA. This difference in TX power can result in a difference between the range of downlink and uplink signal transmission in a WLAN system.

[0006] In wireless LAN systems, replication of RUs in the frequency domain can be performed in units of a specific size to increase signal transmission range. This can result in an increase in the peak-to-average power ratio (PAPR).

[0007] This disclosure may propose a method for transmitting / receiving a physical protocol data unit (PPDU) with an improved structure, and related devices. One example of this disclosure proposes an improved Long Training Field (LTF) signal and / or LTF sequence. The technical features of this disclosure may be applied to PPDUs of various types / formats.

[0008] For example, a Physical Protocol Data Unit (PPDU) of this specification may include LTF and data fields. For example, the bandwidth of the PPDU may be 20 MHz.

[0009] For example, the data field may be transmitted via four 52-tone resource units (RUs) that are duplicated in the frequency domain. For example, the four 52-tone RUs may include a first RU, a second RU, a third RU, and a fourth RU that are sequentially positioned in the frequency domain.

[0010] For example, the LTF corresponding to the first RU may be generated based on an LTF sequence. For example, the LTF sequence may include a sequence in which a first sequence including 52 elements is multiplied by at least one first coefficient. For example, the first sequence may be {1, 1, 1, 1, -1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1, 1, -1, 1, -1, 1, 1, 1, -1, -1, 1, 1, 1, 1, 1, -1, -1, 1, -1, 1, -1, -1, 1, 1, 1, -1, -1, -1, 1, 1, -1, -1, -1}.

[0011] An example of this specification proposes a PPDU with an improved structure. The PPDU of this specification can utilize various frequency mapping techniques to increase transmission range. In this case, when an LTF signal is generated according to the LTF sequence of this specification, the transmission range of the PPDU can be increased while minimizing increases in PAPR. This resolves the problem of the AP failing to properly receive PPDUs in the uplink, while preventing increases in PAPR when the terminal generates the PPDU.

[0012] Figure 1 illustrates an example of a transmitting device and / or a receiving device of the present specification.

[0013] Figure 2 is a conceptual diagram showing the structure of a wireless local area network (WLAN).

[0014] Figure 3 is a diagram illustrating a general link setup process.

[0015] Figure 4 illustrates one embodiment of a multi-link (ML).

[0016] Figure 5 illustrates a PPDU transmitted / received by an STA of this specification.

[0017] Figure 6 is a diagram showing the layout of resource units (RUs) used for 20MHz PPDU.

[0018] Figure 7 is a diagram showing the layout of resource units (RUs) used for 40MHz PPDU.

[0019] Figure 8 is a diagram showing the layout of resource units (RUs) used for 80MHz PPDU.

[0020] Figure 9 shows the operation according to UL-MU.

[0021] Figure 10 shows an example of channels used / supported / defined within the 2.4 GHz band.

[0022] Figure 11 illustrates an example of channels used / supported / defined within the 5 GHz band.

[0023] Figure 12 illustrates an example of channels used / supported / defined within the 6 GHz band.

[0024] Figure 13 shows an example of a header of a MAC frame.

[0025] FIG. 14 illustrates a modified example of a transmitting device and / or a receiving device of the present specification.

[0026] Figure 15 illustrates an example of duplicating wireless resources related to data fields of this specification.

[0027] Figure 16 shows an example of an ELR PPDU of this specification.

[0028] Figure 17 is an example of a procedure flowchart related to this specification.

[0029] Figure 18 is an example of a procedure flowchart related to this specification.

[0030] As used herein, "A or B" can mean "only A," "only B," or "both A and B." In other words, as used herein, "A or B" can be interpreted as "A and / or B." For example, as used herein, "A, B or C" can mean "only A," "only B," "only C," or "any combination of A, B and C."

[0031] As used herein, a slash ( / ) or a comma can mean "and / or." For example, "A / B" can mean "A and / or B." Accordingly, "A / B" can mean "only A," "only B," or "both A and B." For example, "A, B, C" can mean "A, B, or C."

[0032] In this specification, "at least one of A and B" may mean "only A", "only B" or "both A and B". Additionally, in this specification, the expressions "at least one of A or B" or "at least one of A and / or B" may be interpreted identically to "at least one of A and B".

[0033] In addition, parentheses used in this specification may mean "for example". Specifically, when it is indicated as "control information (UHR-Signal field)", the "UHR-Signal field" may be proposed as an example of "control information". In other words, the "control information" in this specification is not limited to the "UHR-Signal field", and the "UHR-Signal field" may be proposed as an example of "control information". In addition, even when it is indicated as "control information (UHR-Signal field)", the "UHR-Signal field" may be proposed as an example of "control information".

[0034] Additionally, as used herein, "a / an" can mean "at least one" or "one or more." Additionally, terms ending in "(s)" can mean "at least one" or "one or more."

[0035] Additionally, the expressions "based on" or "on the basis of" or "according to" used herein mean "based at least in part on" and not "based solely on".

[0036] Technical features individually described in a single drawing in this specification may be implemented individually or simultaneously.

[0037] The following examples of this specification can be applied to various wireless communication systems. For example, the following examples of this specification can be applied to wireless local area network (WLAN) systems. For example, the present specification can be applied to the IEEE 802.11a / g / n / ac / ax / be / bn standards. In addition, the examples of this specification can be applied to the Ultra High Reliability (UHR) standard or the next-generation wireless LAN standard that enhances IEEE 802.11bn. In addition, the examples of this specification can be applied to mobile communication systems. For example, the examples of this specification can be applied to mobile communication systems based on Long Term Evolution (LTE) and its evolution based on the 3rd Generation Partnership Project (3GPP) standard.

[0038] In order to explain the technical features of this specification, the technical features to which this specification can be applied are described below.

[0039] Figure 1 illustrates an example of a transmitting device and / or a receiving device of the present specification.

[0040] An example of FIG. 1 can perform various technical features described below. FIG. 1 relates to at least one STA (station). For example, the STA (110, 120) of the present specification may also be referred to by various names such as a mobile terminal, a wireless device, a Wireless Transmit / Receive Unit (WTRU), a User Equipment (UE), a Mobile Station (MS), a Mobile Subscriber Unit, or simply a user. The STA (110, 120) of the present specification may also be referred to by various names such as a network, a base station, a Node-B, an access point (AP), a repeater, a router, a relay, etc. The STA (110, 120) of the present specification may also be referred to by various names such as a receiving apparatus, a transmitting apparatus, a receiving STA, a transmitting STA, a receiving device, a transmitting device, etc.

[0041] For example, STA (110, 120) may perform the role of an AP (access point) or a non-AP role. That is, STA (110, 120) of the present specification may perform the functions of an AP and / or a non-AP. In the present specification, AP may also be indicated as an AP STA.

[0042] The STA (110, 120) of this specification can support various communication standards other than the IEEE 802.11 standard. For example, it can support communication standards according to the 3GPP standard (e.g., LTE, LTE-A, 5G NR standard). In addition, the STA of this specification can be implemented in various devices such as a mobile phone, a vehicle, a personal computer, etc. In addition, the STA of this specification can support communication for various communication services such as voice calls, video calls, data communications, and autonomous driving (self-driving, autonomous-driving).

[0043] In this specification, STA (110, 120) may include a medium access control (MAC) and a physical layer interface for a wireless medium that follow the provisions of the IEEE 802.11 standard.

[0044] Based on the sub-drawing (a) of Fig. 1, STA (110, 120) is described as follows.

[0045] The first STA (110) may include a processor (111), a memory (112), and a transceiver (113). The illustrated processor, memory, and transceiver may each be implemented as separate chips, or at least two blocks / functions may be implemented through a single chip.

[0046] The transceiver (113) of the first STA performs signal transmission and reception operations. Specifically, it can transmit and receive IEEE 802.11 packets (e.g., IEEE 802.11a / b / g / n / ac / ax / be, etc.).

[0047] For example, the first STA (110) can perform the intended operation of the AP. For example, the processor (111) of the AP can receive a signal through the transceiver (113), process the received signal, generate a transmission signal, and perform control for signal transmission. The memory (112) of the AP can store a signal (e.g., a received signal) received through the transceiver (113) and store a signal (e.g., a transmitted signal) to be transmitted through the transceiver.

[0048] For example, the second STA (120) can perform the intended operation of a non-AP STA. For example, the transceiver (123) of the non-AP performs signal transmission and reception operations. Specifically, it can transmit and receive IEEE 802.11 packets (e.g., IEEE 802.11a / b / g / n / ac / ax / be, etc.).

[0049] For example, the processor (121) of the Non-AP STA can receive a signal through the transceiver (123), process the received signal, generate a transmission signal, and perform control for signal transmission. The memory (122) of the Non-AP STA can store a signal (e.g., a reception signal) received through the transceiver (123) and store a signal (e.g., a transmission signal) to be transmitted through the transceiver.

[0050] For example, in the specification below, the operation of a device indicated as AP may be performed in the first STA (110) or the second STA (120). For example, if the first STA (110) is an AP, the operation of the device indicated as AP may be controlled by the processor (111) of the first STA (110), and a related signal may be transmitted or received through a transceiver (113) controlled by the processor (111) of the first STA (110). In addition, control information related to the operation of the AP or a transmission / reception signal of the AP may be stored in the memory (112) of the first STA (110). In addition, when the second STA (110) is an AP, the operation of the device indicated as an AP is controlled by the processor (121) of the second STA (120), and a related signal can be transmitted or received through a transceiver (123) controlled by the processor (121) of the second STA (120). In addition, control information related to the operation of the AP or the transmission / reception signal of the AP can be stored in the memory (122) of the second STA (110).

[0051] For example, in the specification below, the operation of a device indicated as a non-AP (or User-STA) may be performed in the STA (110) or the second STA (120). For example, if the second STA (120) is a non-AP, the operation of the device indicated as a non-AP may be controlled by the processor (121) of the second STA (120), and a related signal may be transmitted or received through a transceiver (123) controlled by the processor (121) of the second STA (120). In addition, control information related to the operation of the non-AP or the transmission / reception signal of the AP may be stored in the memory (122) of the second STA (120). For example, if the first STA (110) is a non-AP, the operation of a device indicated as a non-AP is controlled by the processor (111) of the first STA (110), and a related signal may be transmitted or received through a transceiver (113) controlled by the processor (111) of the first STA (120). In addition, control information related to the operation of the non-AP or the transmission / reception signal of the AP may be stored in the memory (112) of the first STA (110).

[0052] In the following specification, devices called (transmitting / receiving) STA, first STA, second STA, STA1, STA2, AP, first AP, second AP, AP1, AP2, (transmitting / receiving) Terminal, (transmitting / receiving) device, (transmitting / receiving) apparatus, network, etc. may refer to the STA (110, 120) of FIG. 1. For example, devices indicated as (transmitting / receiving) STA, first STA, second STA, STA1, STA2, AP, first AP, second AP, AP1, AP2, (transmitting / receiving) Terminal, (transmitting / receiving) device, (transmitting / receiving) apparatus, network, etc. without specific drawing symbols may also refer to the STA (110, 120) of FIG. 1. For example, in the example below, the operation of various STAs transmitting and receiving signals (e.g., PPPDU) may be performed by the transceiver (113, 123) of FIG. 1. In addition, in the example below, the operation of various STAs generating transmission and reception signals or performing data processing or calculations in advance for transmission and reception signals may be performed by the processor (111, 121) of FIG. 1.For example, an example of an operation for generating a transmission / reception signal or performing data processing or operation in advance for a transmission / reception signal may include 1) an operation for determining / obtaining / configuring / computing / decoding / encoding bit information of a subfield (SIG, STF, LTF, Data) field included in a PPDU, 2) an operation for determining / configuring / obtaining time resources or frequency resources (e.g., subcarrier resources) used for a subfield (SIG, STF, LTF, Data) field included in a PPDU, 3) an operation for determining / configuring / obtaining a specific sequence (e.g., a pilot sequence, an STF / LTF sequence, an extra sequence applied to SIG) used for a subfield (SIG, STF, LTF, Data) field included in a PPDU, 4) a power control operation and / or a power saving operation applied to an STA, 5) an operation related to determining / obtaining / configuring / computing / decoding / encoding an ACK signal, etc. Additionally, in the examples below, various information (e.g., information related to fields / subfields / control fields / parameters / power, etc.) used by various STAs for determining / acquiring / configuring / computing / decoding / encoding transmission / reception signals can be stored in the memory (112, 122) of FIG. 1.

[0053] The device / STA of the sub-drawing (a) of the above-described FIG. 1 can be modified as in the sub-drawing (b) of FIG. 1. Hereinafter, the STA (110, 120) of the present specification will be described based on the sub-drawing (b) of FIG. 1.

[0054] For example, the transceiver (113, 123) illustrated in sub-drawing (b) of FIG. 1 may perform the same function as the transceiver illustrated in sub-drawing (a) of FIG. 1 described above. For example, the processing chip (114, 124) illustrated in sub-drawing (b) of FIG. 1 may include a processor (111, 121) and a memory (112, 122). The processor (111, 121) and the memory (112, 122) illustrated in sub-drawing (b) of FIG. 1 may perform the same function as the processor (111, 121) and the memory (112, 122) illustrated in sub-drawing (a) of FIG. 1 described above.

[0055] The mobile terminal, wireless device, Wireless Transmit / Receive Unit (WTRU), User Equipment (UE), Mobile Station (MS), Mobile Subscriber Unit, user, user STA, network, Base Station, Node-B, Access Point (AP), repeater, router, relay, receiving device, transmitting device, receiving STA, transmitting STA, receiving Device, transmitting Device, receiving Apparatus, and / or transmitting Apparatus described below may refer to the STA (110, 120) illustrated in the sub-drawings (a) / (b) of FIG. 1, or may refer to the processing chip (114, 124) illustrated in the sub-drawing (b) of FIG. 1. That is, the technical feature of the present specification may be performed in the STA (110, 120) illustrated in the sub-drawings (a) / (b) of FIG. 1, or may be performed only in the processing chip (114, 124) illustrated in the sub-drawings (b) of FIG. 1. For example, the technical feature that the transmitting STA transmits a control signal may be understood as a technical feature that the control signal generated in the processor (111, 121) illustrated in the sub-drawings (a) / (b) of FIG. 1 is transmitted through the transceiver (113, 123) illustrated in the sub-drawings (a) / (b) of FIG. 1. Alternatively, the technical feature that the transmitting STA transmits a control signal may be understood as a technical feature that the control signal to be transmitted to the transceiver (113, 123) is generated in the processing chip (114, 124) illustrated in the sub-drawings (b) of FIG. 1.

[0056] For example, the technical feature of a receiving STA receiving a control signal can be understood as a technical feature of a control signal being received by a transceiver (113, 123) illustrated in sub-drawing (a) of FIG. 1. Alternatively, the technical feature of a receiving STA receiving a control signal can be understood as a technical feature of a control signal received by a transceiver (113, 123) illustrated in sub-drawing (a) of FIG. 1 being acquired by a processor (111, 121) illustrated in sub-drawing (a) of FIG. 1. Alternatively, the technical feature of a receiving STA receiving a control signal can be understood as a technical feature of a control signal received by a transceiver (113, 123) illustrated in sub-drawing (b) of FIG. 1 being acquired by a processing chip (114, 124) illustrated in sub-drawing (b) of FIG.

[0057] Referring to the sub-drawing (b) of FIG. 1, software code (115, 125) may be included in the memory (112, 122). The software code (115, 125) may include instructions that control the operation of the processor (111, 121). The software code (115, 125) may be included in various programming languages.

[0058] The processor (111, 121) or processing chip (114, 124) illustrated in FIG. 1 may include an application-specific integrated circuit (ASIC), another chipset, a logic circuit, and / or a data processing device. The processor may be an application processor (AP). For example, the processor (111, 121) or processing chip (114, 124) illustrated in FIG. 1 may include at least one of a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), and a modem (modulator and demodulator). For example, the processor (111, 121) or processing chip (114, 124) illustrated in FIG. 1 may be a SNAPDRAGON® series processor manufactured by Qualcomm®, an EXYNOS® series processor manufactured by Samsung®, an A series processor manufactured by Apple®, a HELIO® series processor manufactured by MediaTek®, an ATOM® series processor manufactured by INTEL®, or an enhanced processor thereof.

[0059] In this specification, uplink may mean a link for communication from a non-AP STA to an AP STA, and uplink PPDU / packet / signal, etc. may be transmitted through the uplink. In addition, in this specification, downlink may mean a link for communication from an AP STA to a non-AP STA, and downlink PPDU / packet / signal, etc. may be transmitted through the downlink.

[0060] Figure 2 is a conceptual diagram showing the structure of a wireless local area network (WLAN).

[0061] The upper part of Figure 2 shows the structure of the infrastructure BSS (basic service set) of IEEE (institute of electrical and electronic engineers) 802.11.

[0062] Referring to the top of FIG. 2, the wireless LAN system may include one or more infrastructure BSSs (200, 205) (hereinafter, BSS). The BSSs (200, 205) are a collection of APs and STAs, such as an access point (AP) 225 and a station (STA1, 200-1), that have successfully synchronized and can communicate with each other, and are not a concept that designates a specific area. The BSS (205) may also include one or more STAs (205-1, 205-2) that can be associated with one AP (230).

[0063] The BSS may include at least one STA, an AP (225, 230) providing a distribution service, and a distribution system (DS, 210) connecting multiple APs.

[0064] A distributed system (210) can connect multiple BSSs (200, 205) to implement an extended service set (ESS) 240. An ESS (240) can be used as a term to indicate a network formed by connecting one or more APs through the distributed system (210). APs included in a single ESS (240) can have the same SSID (service set identification).

[0065] The portal (portal, 220) can act as a bridge to connect a wireless LAN network (IEEE 802.11) to another network (e.g., 802.X).

[0066] In a BSS such as the upper part of Fig. 2, a network between APs (225, 230) and a network between APs (225, 230) and STAs (200-1, 205-1, 205-2) can be implemented. However, it may also be possible to establish a network and perform communication between STAs without an AP (225, 230). A network that establishes a network and performs communication between STAs without an AP (225, 230) is defined as an ad-hoc network or an independent basic service set (IBSS).

[0067] The bottom of Figure 2 is a conceptual diagram showing IBSS.

[0068] Referring to the bottom of Fig. 2, the IBSS is a BSS that operates in ad-hoc mode. Since the IBSS does not include an AP, there is no centralized management entity. That is, in the IBSS, the STAs (250-1, 250-2, 250-3, 255-4, 255-5) are managed in a distributed manner. In the IBSS, all STAs (250-1, 250-2, 250-3, 255-4, 255-5) can be mobile STAs, and access to the distributed system is not permitted, forming a self-contained network.

[0069] Figure 3 is a diagram illustrating a general link setup process.

[0070] In step S310, the STA may perform a network discovery operation. This network discovery operation may include scanning by the STA. That is, for the STA to access the network, it must find a network it can join. Before joining a wireless network, the STA must identify compatible networks. The process of identifying networks in a specific area is called scanning. Scanning methods include active scanning and passive scanning.

[0071] Figure 3 illustrates a network discovery operation that includes an active scanning process as an example. In active scanning, an STA performing scanning transmits a probe request frame to discover which APs exist in the vicinity while moving between channels and waits for a response. A responder transmits a probe response frame to the STA that transmitted the probe request frame in response to the probe request frame. Here, the responder may be the STA that last transmitted a beacon frame in the BSS of the channel being scanned. In a BSS, the AP transmits the beacon frame, so the AP becomes the responder. In an IBSS, the STAs within the IBSS take turns transmitting beacon frames, so the responder is not constant. For example, an STA that transmits a probe request frame on channel 1 and receives a probe response frame on channel 1 can store BSS-related information included in the received probe response frame and move to the next channel (e.g., channel 2) to perform scanning (e.g., transmitting and receiving probe requests / responses on channel 2) in the same manner.

[0072] Although not shown in the example of FIG. 3, the scanning operation can also be performed in a passive scanning manner. An STA performing scanning based on passive scanning can wait for a beacon frame while moving between channels. A beacon frame is one of the management frames in IEEE 802.11. It announces the presence of a wireless network and is periodically transmitted so that the scanning STA can find the wireless network and participate in the wireless network. In the BSS, the AP periodically transmits the beacon frame, and in the IBSS, the STAs within the IBSS take turns transmitting the beacon frame. When the scanning STA receives a beacon frame, it stores the information about the BSS included in the beacon frame and moves to another channel, recording the beacon frame information on each channel. An STA that receives a beacon frame can store the BSS-related information included in the received beacon frame, move to the next channel, and perform scanning on the next channel in the same manner.

[0073] An STA that discovers a network can perform an authentication process through step S320. This authentication process may be referred to as the first authentication process to clearly distinguish it from the security setup operation of step S340 described below. The authentication process of S320 may include a process in which the STA transmits an authentication request frame to the AP, and the AP responds by transmitting an authentication response frame to the STA. The authentication frame used for the authentication request / response corresponds to a management frame.

[0074] The authentication frame may include information such as an authentication algorithm number, an authentication transaction sequence number, a status code, a challenge text, a Robust Security Network (RSN), and a Finite Cyclic Group.

[0075] An STA can transmit an authentication request frame to an AP. The AP can determine whether to grant authentication to the STA based on the information contained in the received authentication request frame. The AP can provide the result of the authentication process to the STA via an authentication response frame.

[0076] A successfully authenticated STA may perform an association process based on step S330. The association process includes a process in which the STA transmits an association request frame to the AP, and the AP transmits an association response frame to the STA in response. For example, the association request frame may include information related to various capabilities, such as a beacon listen interval, a service set identifier (SSID), supported rates, supported channels, RSN, mobility domain, supported operating classes, a Traffic Indication Map Broadcast request, and interworking service capabilities. For example, the association response frame may contain information related to various capabilities, status codes, Association ID (AID), supported rates, Enhanced Distributed Channel Access (EDCA) parameter sets, Received Channel Power Indicator (RCPI), Received Signal to Noise Indicator (RSNI), mobility domains, timeout interval (association comeback time), overlapping BSS scan parameters, TIM broadcast response, QoS maps, etc.

[0077] In step S340, the STA may perform a security setup process. The security setup process of step S340 may include, for example, a process of setting up a private key through a four-way handshaking using an Extensible Authentication Protocol over LAN (EAPOL) frame.

[0078] Figure 4 illustrates one embodiment of a multi-link (ML).

[0079] As illustrated in FIG. 4, multiple multi-link devices (MLDs) can communicate over a remote link. The MLDs can be categorized into AP MLDs including multiple AP STAs and non-AP MLDs including multiple non-AP STAs. That is, the AP MLD can include affiliated APs (e.g., AP STAs), and the non-AP MLD can include affiliated STAs (e.g., non-AP STAs, or user-STAs).

[0080] A multilink may include a first link and a second link, and different channels / subchannels / frequency resources may be allocated to the first and second links. The first and second multilinks may be identified through a link ID of 4 bits (or other n bits). The first and second links may be configured in the same 2.4 GHz, 5 GHz, or 6 GHz band. Alternatively, the first link and the second link may be configured in different bands.

[0081] The AP MLD of FIG. 4 includes three affiliated APs. In the example of FIG. 4, AP1 may operate in the 2.4 GHz band, AP2 may operate in the 5 GHz band, and AP3 may operate in the 6 GHz band. In the example of FIG. 4, the first link in which AP1 and non-AP1 operate may be defined as a channel / subchannel / frequency resource within the 2.4 GHz band. Furthermore, in the example of FIG. 4, the second link in which AP2 and non-AP2 operate may be defined as a channel / subchannel / frequency resource within the 5 GHz band. Furthermore, in the example of FIG. 4, the third link in which AP3 and non-AP3 operate may be defined as a channel / subchannel / frequency resource within the 6 GHz band.

[0082] In the example of FIG. 4, AP1 can initiate a multi-link setup procedure (ML setup procedure) by transmitting an Association Request frame to non-AP STA1. In the example of FIG. 4, non-AP STA1 can transmit an Association Response frame in response to the Association Request frame. Each AP (e.g., AP1 / 2 / 3) illustrated in FIG. 4 may be identical to the AP illustrated in FIG. 1 and / or FIG. 2, and each non-AP (e.g., non-AP1 / 2 / 3) illustrated in FIG. 4 may be identical to the STA (e.g., user-STA or non-AP STA) illustrated in FIG. 1 and / or FIG. 2.

[0083] The specific features of this specification are not limited to the specific features of FIG. 4. That is, the number of links can be defined in various ways, and multiple links can be defined in various ways within at least one band.

[0084] FIG. 5 illustrates a PPDU (physical protocol data unit or physical layer (PHY) protocol data unit) transmitted / received by an STA of this specification.

[0085] The STA (e.g., AP STA, non-AP STA, AP MLD, non-AP MLD) of the present specification can transmit and / or receive the PPDU of FIG. 5. The PPDU described in the present specification may have, for example, the structure of FIG. 5. In addition, the PPDU described in the present specification may be called by various names such as a transmission PPDU, a reception PPDU, a first type PPDU, or an Nth type PPDU, etc. The PPDU described in the present specification can be used in a WLAN system defined according to IEEE 802.11bn and / or a next-generation WLAN system that improves IEEE 802.11bn.

[0086] The PPDU of FIG. 5 may be related to various PPDU types used in a UHR system. For example, the example of FIG. 5 may be used for at least one of a single-user (SU) mode / type / transmission, a multi-user (MU) mode / type / transmission, and a null data packet (NDP) mode / type / transmission related to channel sounding. For example, if the example of FIG. 5 is related to NDP, the Data field illustrated may be omitted. If the PPDU of FIG. 5 is used for a trigger-based (TB) mode, the UHR-SIG of FIG. 5 may be omitted. In other words, an STA that has received a trigger frame for UL-MU (Uplink-MU) communication may transmit a PPDU with the UHR-SIG omitted in the example of FIG. 5.

[0087] In FIG. 5, L-STF or UHR-LTF may be called a preamble or physical preamble, and may be generated / transmitted / received / acquired / decoded in the physical layer (included in the transmitting / receiving STA).

[0088] Each block illustrated in Fig. 5 may be called a field / subfield / signal, etc. The names of these fields / subfields / signals may be, as illustrated in Fig. 5, L-STF (legacy short training field), L-LTF (legacy long training field), L-SIG (legacy signal), RL-SIG (repeated L-SIG), U-SIG (Universal Signal), UHR-SIG (UHR-signal), etc.

[0089] The subcarrier spacing of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and UHR-SIG fields in FIG. 5 may be set to 312.5 kHz, and the subcarrier spacing of the UHR-STF, UHR-LTF, and Data fields may be set to 78.125 kHz. That is, the tone index (or subcarrier index) of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and UHR-SIG fields may be expressed in units of 312.5 kHz, and the tone index (or subcarrier index) of the UHR-STF, UHR-LTF, and Data fields may be expressed in units of 78.125 kHz.

[0090] In the PPDU of Fig. 5, L-LTF and L-STF may be identical to conventional fields (e.g., non-HT LTF and non-HT STF defined in conventional WLAN standards).

[0091] The L-SIG field of FIG. 5 may include, for example, 24 bits of bit information. For example, the 24 bits of information may include a 4 bit Rate field, a 1 bit Reserved bit, a 12 bit Length field, a 1 bit Parity bit, and a 6 bit Tail bit. For example, the 12 bit Length field may include information about the length or time duration of the PPDU. For example, the value of the 12 bit Length field may be determined based on the type of the PPDU. For example, if the PPDU is a non-HT (non-High Throughput), HT (High Throughput), VHT (Very High Throughput) PPDU, or an EHT (extremely high throughput) PPDU or UHR PPDU, the value of the Length field may be determined as a multiple of 3. For example, if the PPDU is a HE PPDU, the value of the Length field may be determined as "a multiple of 3 + 1" or "a multiple of 3 + 2". In other words, for non-HT, HT, VHT PPDU, EHT PPDU, UHR PPDU, the value of the Length field can be determined as a multiple of 3, and for HE (High Efficiency) PPDU, the value of the Length field can be determined as "a multiple of 3 + 1" or "a multiple of 3 + 2". In other words, the Length field in an UHR PPDU is set to a value satisfying the condition that the remainder is zero when LENGTH is divided by 3.

[0092] For example, (non-AP and AP) STAs can apply BCC encoding based on a code rate of 1 / 2 to the 24 bits of information in the L-SIG field. Then, the transmitting STA can obtain 48 BCC coded bits. BPSK modulation can be applied to the 48 coded bits to generate 48 BPSK symbols. The transmitting STA can map the 48 BPSK symbols to positions excluding the pilot subcarriers {subcarrier index -21, -7, +7, +21} and the DC subcarrier {subcarrier index 0}. As a result, the 48 BPSK symbols can be mapped to subcarrier indices -26 to -22, -20 to -8, -6 to -1, +1 to +6, +8 to +20, and +22 to +26. The transmitting STA can additionally map the signal {-1, -1, -1, 1} to the subcarrier indices {-28, -27, +27, +28}. The above signal can be used for channel estimation for the frequency domain corresponding to {-28, -27, +27, +28}.

[0093] For example, (non-AP and AP) STA can generate RL-SIG, which is generated in the same manner as L-SIG. BPSK modulation can be applied to RL-SIG. Receiving (non-AP and AP) STA can determine whether the received PPDU is a HE PPDU, EHT PPDU, or UHR PPDU based on the presence of RL-SIG. In other words, if RL-SIG is present, receiving (non-AP and AP) STA can determine whether the received PPDU is one of HE PPDU, EHT PPDU, or UHR PPDU. In other words, if RL-SIG is not present, receiving (non-AP and AP) STA can determine whether the received PPDU is one of non-HT PPDU, HT PPDU, or VHT PPDU. In other words, the RL-SIG field is a repeat of the L-SIG field and is used to differentiate an UHR PPDU from a non-HT PPDU, HT PPDU, and VHT PPDU.

[0094] After the RL-SIG in Fig. 5, a U-SIG (Universal SIG) may be inserted. The U-SIG may be called by various names such as the first SIG field, the first SIG, the first type SIG, the control signal, the control signal field, the first (type) control signal, the common control field, and the common control signal.

[0095] A U-SIG can contain N bits of information and can include information for identifying the type of EHT PPDU. For example, a U-SIG can be formed based on two symbols (e.g., two consecutive OFDM symbols). Each symbol (e.g., an OFDM symbol) for a U-SIG can have a duration of 4 μs. Each symbol of a U-SIG can be used to transmit 26 bits of information. For example, each symbol of a U-SIG can be transmitted and received based on 52 data tones and 4 pilot tones.

[0096] For example, A bit information (e.g., 52 uncoded bits) can be transmitted through U-SIG, and the first symbol of U-SIG can transmit the first X bits of information (e.g., 26 uncoded bits) out of the total A bit information, and the second symbol of U-SIG can transmit the remaining Y bits of information (e.g., 26 uncoded bits) out of the total A bit information. For example, the transmitting STA can obtain 26 uncoded bits included in each U-SIG symbol. The transmitting STA can perform convolutional encoding (e.g., BCC encoding) based on a rate of R=1 / 2 to generate 52 coded bits, and perform interleaving on the 52 coded bits. The transmitting STA can perform BPSK modulation on the interleaved 52 coded bits to generate 52 BPSK symbols allocated to each U-SIG symbol. A single U-SIG symbol can be transmitted based on 56 tones (subcarriers) from subcarrier index -28 to subcarrier index +28, excluding DC index 0. The 52 BPSK symbols generated by the transmitting STA can be transmitted based on the remaining tones (subcarriers) excluding the pilot tones -21, -7, +7, and +21.

[0097] For example, A bit information (e.g., 52 uncoded bits) transmitted by U-SIG may include a CRC field (e.g., a 4-bit long field) and a tail field (e.g., a 6-bit long field). The CRC field and the tail field may be transmitted through the second symbol of the U-SIG. The CRC field may be generated based on 26 bits allocated to the first symbol of the U-SIG and the remaining 16 bits excluding the CRC / tail field within the second symbol, and may be generated based on a conventional CRC calculation algorithm. In addition, the tail field may be used to terminate the trellis of the convolutional decoder and may be set to, for example, "000000".

[0098] The A bit information (e.g., 52 uncoded bits) transmitted by the U-SIG (or U-SIG field) can be divided into version-independent bits and version-dependent bits. For example, the size of the version-independent bits can be fixed or variable. For example, the version-independent bits can be assigned only to the first symbol of the U-SIG, or the version-independent bits can be assigned to both the first symbol and the second symbol of the U-SIG. For example, the version-independent bits and the version-dependent bits can be called by various names, such as the first control bit and the second control bit.

[0099] For example, the version-independent bits of the U-SIG may include a 3-bit PHY version identifier. For example, the 3-bit PHY version identifier may include information related to the PHY version of the transmitted and received PPDU. For example, a first value (e.g., a value of 000) of the 3-bit PHY version identifier may indicate that the transmitted and received PPDU is an EHT PPDU. In addition, a second value (e.g., a value of 001) of the 3-bit PHY version identifier may indicate that the transmitted and received PPDU is an UHR PPDU.

[0100] In other words, when the (AP / non-AP) STA transmits an EHT PPDU, it can set the 3-bit PHY version identifier to the first value. In other words, the receiving (AP / non-AP) STA can determine that the received PPDU is an EHT PPDU based on the PHY version identifier having the first value, and can determine that the received PPDU is an UHR PPDU based on the PHY version identifier having the second value.

[0101] For example, the version-independent bits of U-SIG may include a 1-bit UL / DL flag field. The first value of the 1-bit UL / DL flag field relates to UL communication, and the second value of the UL / DL flag field relates to DL communication.

[0102] For example, the version-independent bits of U-SIG may contain information about the length of the TXOP and information about the BSS color ID.

[0103] For example, if a UHR PPDU is classified into various types (e.g., a type related to SU transmission (performed based on UL or DL), a type related to DL transmission, a type related to NDP transmission, a type related to DL non-MU-MIMO, a type related to DL MU-MIMO, a type related to Multi-AP operation, a type related to CBF (Coordinated beamforming), SR (Spatial Reuse), a type related to C-OFDMA (Coordinated OFDMA), a type related to C-TDMA (Coordinated TDMA)), information about the type of the EHT PPDU (e.g., 2-bit or 3-bit information) can be included in the version-dependent bits of the U-SIG.

[0104] For example, U-SIG may include 1) a bandwidth field including information about bandwidth, 2) a field including information about a Modulation and Coding Scheme (MCS) technique applied to UHR-SIG, 3) an indication field including information about whether a dual subcarrier modulation (DCM) technique is applied to UHR-SIG, 4) a field including information about the number of symbols used for UHR-SIG, 5) a field including information about whether UHR-SIG is generated over the entire band, 6) a field including information about the type of UHR-LTF / STF, and 7) a field indicating the length of UHR-LTF and the CP length.

[0105] Preamble puncturing may be applied to the PPDU of FIG. 5. Preamble puncturing refers to applying puncturing to a portion of the entire bandwidth of the PPDU (e.g., the secondary 20 MHz band). For example, when an 80 MHz PPDU is transmitted, the STA applies puncturing to the secondary 20 MHz band within the 80 MHz band, and can transmit the PPDU only through the primary 20 MHz band and the secondary 40 MHz band.

[0106] For example, the pattern of preamble puncturing can be preset. For example, when the first puncturing pattern is applied, puncturing can be applied only to the secondary 20 MHz band within the 80 MHz band. For example, when the second puncturing pattern is applied, puncturing can be applied only to one of the two secondary 20 MHz bands included in the secondary 40 MHz band within the 80 MHz band. For example, when the third puncturing pattern is applied, puncturing can be applied only to the secondary 20 MHz band included in the primary 80 MHz band within the 160 MHz band (or 80+80 MHz band). For example, when the fourth puncturing pattern is applied, a primary 40 MHz band included in the primary 80 MHz band within the 160 MHz band (or 80+80 MHz band) may be present, and puncturing may be applied to at least one 20 MHz channel that does not belong to the primary 40 MHz band.

[0107] Information regarding preamble puncturing applied to the PPDU may be included in the U-SIG and / or UHR-SIG. For example, the first field of the U-SIG may include information regarding the contiguous bandwidth of the PPDU, and the second field of the U-SIG may include information regarding preamble puncturing applied to the PPDU.

[0108] For example, U-SIG and UHR-SIG may include information regarding preamble puncturing based on the following method. If the bandwidth of the PPDU exceeds 80 MHz, the U-SIGs may be individually configured in units of 80 MHz. For example, if the bandwidth of the PPDU is 160 MHz, the PPDU may include a first U-SIG for the first 80 MHz band and a second U-SIG for the second 80 MHz band. In this case, the first field of the first U-SIG may include information regarding the 160 MHz bandwidth, and the second field of the first U-SIG may include information regarding preamble puncturing applied to the first 80 MHz band (e.g., information regarding a preamble puncturing pattern). Additionally, the first field of the second U-SIG may include information regarding a 160 MHz bandwidth, and the second field of the second U-SIG may include information regarding preamble puncturing applied to the second 80 MHz band (e.g., information regarding a preamble puncturing pattern). Meanwhile, the UHR-SIG consecutive to the first U-SIG may include information regarding preamble puncturing applied to the second 80 MHz band (e.g., information regarding a preamble puncturing pattern), and the UHR-SIG consecutive to the second U-SIG may include information regarding preamble puncturing applied to the first 80 MHz band (e.g., information regarding a preamble puncturing pattern).

[0109] Additionally or alternatively, U-SIG and UHR-SIG may include information regarding preamble puncturing based on the following methods. U-SIG may include information regarding preamble puncturing for all bands (e.g., information regarding preamble puncturing patterns). That is, UHR-SIG may not include information regarding preamble puncturing, and only U-SIG may include information regarding preamble puncturing (e.g., information regarding preamble puncturing patterns).

[0110] U-SIGs can be configured in 20 MHz units. For example, if an 80 MHz PPDU is configured, U-SIGs can be duplicated. That is, four identical U-SIGs can be included within an 80 MHz PPDU. PPDUs exceeding the 80 MHz bandwidth can contain different U-SIGs.

[0111] The UHR-SIG of FIG. 5 may include control information for a receiving STA. The UHR-SIG may be transmitted over at least one symbol, and each symbol may have a length of 4 μs. Information regarding the number of symbols used for the UHR-SIG may be included in the U-SIG.

[0112] UHR-SIG provides additional signals to the U-SIG field to enable STAs to interpret / decode UHR PPDUs. The UHR-SIG field may contain U-SIG overflow bits that are common to all users. The UHR-SIG field also contains resource allocation information, allowing STAs to look up resources used in fields containing data fields / UHR-STF / UHR-LTF (e.g., UHR modulated fields of an UHR PPDU).

[0113] The frequency resources of the UHR-LTF, UHR-STF, and data fields illustrated in FIG. 5 can be determined based on RUs (resource units) defined by multiple subcarriers / tones. That is, the UHR-LTF, UHR-STF, and data fields of this specification can be transmitted / received through RUs (resource units) defined by multiple subcarriers / tones.

[0114] FIG. 6 is a diagram illustrating the layout of resource units (RUs) used for a 20 MHz PPDU. That is, the UHR-LTF, UHR-STF, and / or data fields included in the 20 MHz PPDU can be transmitted / received through at least one of the various RUs defined in FIG. 6.

[0115] As shown at the top of Fig. 6, 26 units (e.g., units corresponding to 26 tones) may be arranged. 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. In addition, 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 each side of the DC band. In addition, 26 units, 52 units, and 106 units may be allocated to other bands. Each unit may be allocated for a receiving station, i.e., a user.

[0116] Meanwhile, the RU arrangement of FIG. 6 is utilized not only in a situation for multiple users (MUs) but also in a situation for a single user (SU), in which case it is possible to use one 242-unit as shown at the bottom of FIG. 4, in which case three DC tones can be inserted.

[0117] In the example of Fig. 6, RUs of various sizes, such as 26-RU, 52-RU, 106-RU, and 242-RU, are proposed. Since the specific sizes of these RUs can be expanded or increased, the present embodiment is not limited to the specific sizes of each RU (e.g., the number of corresponding tones). In this specification, N-RU may be represented as N-tone RU, etc. For example, 26-RU may be represented as 26-tone RU.

[0118] Figure 7 is a diagram showing the layout of resource units (RUs) used for 40MHz PPDU.

[0119] As in the example of Fig. 6 where RUs of various sizes were used, the example of Fig. 7 can also use 26-RU, 52-RU, 106-RU, 242-RU, 484-RU, etc. In addition, 5 DC tones can be inserted at the center frequency, 12 tones can be used as a guard band in the leftmost band of the 40 MHz band, and 11 tones can be used as a guard band in the rightmost band of the 40 MHz band.

[0120] Additionally, as illustrated, 484 RUs may be used when used for a single user. Meanwhile, the specific number of RUs may be changed, as in the example of FIG. 6.

[0121] Figure 8 is a diagram illustrating the layout of resource units (RUs) used for an 80MHz PPDU. The layout of resource units (RUs) used in this specification may vary. For example, the layout of resource units (RUs) used in the 80MHz band may vary.

[0122] Figure 9 illustrates an operation according to UL-MU. As illustrated, a transmitting STA (e.g., AP) can acquire a TXOP (925) by performing channel access through contending (e.g., backoff operation) and transmit a trigger frame (930). That is, the transmitting STA (e.g., AP) can transmit a PPDU including a trigger frame (930). When a PPDU including a trigger frame is received, a TB (trigger-based) PPDU is transmitted after a delay of SIFS.

[0123] TB PPDUs (941, 942) are transmitted at the same time and can be transmitted from multiple STAs (e.g., User STAs) whose AIDs are indicated in the Trigger frame (930). The ACK frame (950) for the TB PPDU can be implemented in various forms. For example, the ACK frame (950) for the TB PPDU can be implemented in the form of a BA (block ACK).

[0124] In FIG. 9, transmission(s) of a Trigger Frame (930), TB PPDU (941, 942) and / or ACK frame (950) can be performed within a TXOP (925).

[0125] Figure 10 shows an example of channels used / supported / defined within the 2.4 GHz band.

[0126] The 2.4 GHz band may be referred to by other names, such as the first band (band). Furthermore, the 2.4 GHz band may refer to a frequency range in which channels with a center frequency adjacent to 2.4 GHz (e.g., channels with a center frequency between 2.4 and 2.5 GHz) are used / supported / defined.

[0127] The 2.4 GHz band may include multiple 20 MHz channels. The 20 MHz within the 2.4 GHz band may have multiple channel indices (e.g., indices 1 through 14). For example, the center frequency of a 20 MHz channel assigned channel index 1 may be 2.412 GHz, the center frequency of a 20 MHz channel assigned channel index 2 may be 2.417 GHz, and the center frequency of a 20 MHz channel assigned channel index N may be (2.407 + 0.005*N) GHz. The channel indices may be referred to by various names, such as channel numbers. The specific numerical values ​​of the channel indices and center frequencies may change.

[0128] Figure 10 exemplarily illustrates four channels within the 2.4 GHz band. The illustrated first frequency region (1010) to fourth frequency region (1040) may each include one channel. For example, the first frequency region (1010) may include channel 1 (a 20 MHz channel having an index of 1). In this case, the center frequency of channel 1 may be set to 2412 MHz. The second frequency region (1020) may include channel 6. In this case, the center frequency of channel 6 may be set to 2437 MHz. The third frequency region (1030) may include channel 11. In this case, the center frequency of channel 11 may be set to 2462 MHz. The fourth frequency region (1040) may include channel 14. In this case, the center frequency of channel 14 may be set to 2484 MHz.

[0129] Figure 11 illustrates an example of channels used / supported / defined within the 5 GHz band.

[0130] The 5 GHz band may be referred to by other names, such as a second band / band, etc. The 5 GHz band may refer to a frequency range in which channels with center frequencies greater than or equal to 5 GHz and less than 6 GHz (or less than 5.9 GHz) are used / supported / defined. Alternatively, the 5 GHz band may include multiple channels between 4.5 GHz and 5.5 GHz. The specific figures shown in FIG. 11 are subject to change.

[0131] Multiple channels within the 5 GHz band include Unlicensed National Information Infrastructure (UNII)-1, UNII-2, UNII-3, and ISM. UNII-1 may be referred to as UNII Low. UNII-2 may include frequency ranges called UNII Mid and UNII-2Extended. UNII-3 may be referred to as UNII-Upper.

[0132] Within the 5 GHz band, multiple channels can be configured, and the bandwidth of each channel can be variously configured, such as 20 MHz, 40 MHz, 80 MHz, or 160 MHz. For example, the 5170 MHz to 5330 MHz frequency domain / range within UNII-1 and UNII-2 can be divided into eight 20 MHz channels. The 5170 MHz to 5330 MHz frequency domain / range can be divided into four channels through a 40 MHz frequency domain. The 5170 MHz to 5330 MHz frequency domain / range can be divided into two channels through an 80 MHz frequency domain. Alternatively, the 5170 MHz to 5330 MHz frequency domain / range can be divided into one channel through a 160 MHz frequency domain.

[0133] Figure 12 illustrates an example of channels used / supported / defined within the 6 GHz band.

[0134] The 6 GHz band may also be referred to by other names, such as the third band / band. The 6 GHz band may refer to the frequency range in which channels with center frequencies above 5.9 GHz are used, supported, or defined. The specific figures shown in Figure 12 are subject to change.

[0135] For example, the 20 MHz channel of FIG. 12 can be defined from 5.940 GHz. Specifically, the leftmost channel among the 20 MHz channels of FIG. 12 can have an index of 1 (or channel index, channel number, etc.), and a center frequency of 5.945 GHz can be assigned. That is, the center frequency of the indexed channel N can be determined as (5.940 + 0.005*N) GHz.

[0136] Accordingly, the indexes (or channel numbers) of the 20 MHz channels of FIG. 12 are 1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57, 61, 65, 69, 73, 77, 81, 85, 89, 93, 97, 101, 105, 109, 113, 117, 121, 125, 129, 133, 137, 141, 145, 149, 153, 157, 161, 165, 169, 173, 177, 181, 185, 189, 193, It can be 197, 201, 205, 209, 213, 217, 221, 225, 229, 233. Also, according to the (5.940 + 0.005*N) GHz rule mentioned above, the indices of the 40 MHz channels in Fig. 12 can be 3, 11, 19, 27, 35, 43, 51, 59, 67, 75, 83, 91, 99, 107, 115, 123, 131, 139, 147, 155, 163, 171, 179, 187, 195, 203, 211, 219, 227.

[0137] Below, the structure and types / subtypes of MAC frames are described.

[0138] Fig. 13 illustrates an example of a header of a MAC frame. As illustrated, the MAC frame may include a frame control field / information of 2 octets in length, a duration field / information of 2 octets in length, a RA (Receiver Address) field / information of 6 octets in length, and a TA (Transmitter Address) field / information of 6 octets in length. As illustrated in Fig. 13, the four fields may be consecutive to each other. The MAC header of Fig. 13 may be modified in various ways, and a new field may be inserted between the four illustrated fields, or at least one of the illustrated fields may be omitted.

[0139] The MAC header illustrated in Fig. 13 may be positioned at the very front of a MAC frame. That is, the MAC frame may include a MAC header as illustrated in Fig. 13 and MAC body fields / information subsequent to the MAC header. The MAC frame including the MAC header of Fig. 13 is inserted / included in the data field of the PPDU (e.g., UHR PPDU) illustrated in Fig. 5.

[0140] The MAC frames included in the data field of the PPDU of this specification can be classified into various types. For example, the MAC frames of this specification can be classified into control frames, management frames, and data frames.

[0141] For example, the management frame includes Association Request, Association Response, Reassociation Request, Reassociation Response, Probe Request, Probe Response, Beacon, Disassociation, Authentication, and Deauthentication frames / signals defined in conventional WLAN. For the management frame, the values ​​of the type fields (B3 and B2) in FIG. 13 are set to 00. In addition, the values ​​of the subtype fields (B7, B6, B5, B4) in FIG. 13 are as follows: Association Request (0000), Association Response (0001), Reassociation Request (0010), Reassociation Response (0011), Probe Request (0100), Probe Response (0101), Beacon (1000), Disassociation (1010), Authentication (1011), Deauthentication (1100).

[0142] For example, the control frame includes Trigger Beamforming Report Poll, NDP Announcement (NDPA), Control Frame Extension, Control Wrapper, Block Ack Request (BlockAckReq), Block Ack (BlockAck), PS-Poll, RTS, CTS, Ack, and CF-End frames / signals defined in conventional WLAN. For the control frame, the value of the type field (B3 and B2) in FIG. 13 is set to 01. Also, the values ​​of the subtype fields (B7, B6, B5, B4) of FIG. 13 are as follows: Trigger (0010), Beamforming Report Poll (0100), NDP Announcement (0101), Control Frame Extension (0110), Control Wrapper (0111), BlockAckReq (1000), BlockAck (1001), PS-Poll (1010), RTS (1011), CTS (1100), Ack (1101), CF-End (1110).

[0143] For example, the data frame includes (QoS) Data, (QoS) Null, etc. defined in conventional WLAN. For the management frame, the value of the type field (B3 and B2) of Fig. 13 is set to 10.

[0144] The MAC frame / signal used in this specification can be identified through the type field / information and subtype field / information described above. For example, the "trigger frame" in this specification can mean a MAC frame in which the type bits B3 and B2 bits in the frame control field of the MAC header are set to 01, and the subtype bits B7, B6, B5, B4 bits in the frame control field are also set to 0010. Various MAC frames described in this specification are inserted / included in the data fields of various PPDUs (e.g., HE / VHT / HE / EHT / UHR PPDUs).

[0145] FIG. 14 illustrates a modified example of a transmitting device and / or a receiving device of the present specification.

[0146] The devices (e.g., AP STA, non-AP STA) illustrated in FIGS. 1 to 4 may be modified as illustrated in FIG. 14. The transceiver (630) of FIG. 14 may be identical to the transceivers (113, 123) of FIG. 1. The transceiver (630) of FIG. 14 may include a receiver and a transmitter.

[0147] The processor (610) of FIG. 14 may be identical to the processor (111, 121) of FIG. 1. Alternatively, the processor (610) of FIG. 14 may be identical to the processing chip (114, 124) of FIG. 1.

[0148] The memory (150) of FIG. 14 may be the same as the memory (112, 122) of FIG. 1. Alternatively, the memory (150) of FIG. 14 may be a separate external memory different from the memory (112, 122) of FIG. 1.

[0149] Referring to FIG. 14, a power management module (611) manages power to a processor (610) and / or a transceiver (630). A battery (612) supplies power to the power management module (611). A display (613) outputs results processed by the processor (610). A keypad (614) receives input to be used by the processor (610). The keypad (614) may be displayed on the display (613). A SIM card (615) may be an integrated circuit used to securely store an international mobile subscriber identity (IMSI) and an associated key used to identify and authenticate a subscriber in a mobile phone device, such as a mobile phone or computer.

[0150] Referring to FIG. 14, the speaker (640) can output sound-related results processed by the processor (610). The microphone (641) can receive sound-related input to be used by the processor (610).

[0151] The wireless LAN systems described herein (e.g., IEEE 802.11bn or UHR systems) aim to support ultra-high reliability when transmitting signals to STAs. To achieve this, various technologies are being considered, including high throughput, low latency, and extended range support.

[0152] The technical features of this specification can be applied to various communication systems. For example, examples of this specification can be applied to various wireless LAN systems. For example, examples of this specification can be applied to various wireless LAN standards, in addition to the IEEE 802.11bn (or UHR) system.

[0153] The technical features of this specification can be applied to various types / formats of Physical Protocol Data Units (PPDUs). For example, the technical features of this specification can be used for various types / formats such as single user (SU) PPDU, multiple user (MU) PPDU, null data PPDU (NDP), trigger-based (TB) PPDU, etc. For example, the technical features of this specification can be applied to extended long range (ELR) PPDU. For example, the expression ELR can be replaced with expressions such as long range (LR) or extended range (ER). Accordingly, expressions such as ER transmission or LR transmission can be expressed as ELR transmission.

[0154] Hereinafter, ELR communication is described. In a wireless LAN system (e.g., IEEE 802.11bn or UHR system), LR / ER / ELR communication can be considered to ensure smooth signal transmission and reception for STAs within the coverage boundary of an AP and to overcome the transmission range difference caused by the difference in transmission power between the AP and STAs. For example, the difference in transmission power between an AP and a non-AP STA can be approximately 10 dB. For example, the link budget for the received signal between the AP and the non-AP STA due to this difference in TX power can be approximately 6 dB. For example, long-range transmission to provide a gain of 6 dB, which is the link budget difference, can be performed using the following method.

[0155] For example, an ELR PPDU has a fixed bandwidth of 20 MHz and can be used for both downlink and uplink in the 2.4 GHz band, but only for uplink in the 5 GHz and 6 GHz bands. In other words, an ELR PPDU may consist of only 20 MHz and may not have bandwidths such as 40 / 80 / 160 / 320 MHz.

[0156] For example, to solve technical issues such as power imbalance, the following frequency mapping technique can be applied to specific fields of the ELR PPDU. For example, in order to obtain a gain equivalent to the link budget of the DL and UL, the data field of the ELR PPDU can be transmitted based on a single 52-carrier existing within 20 MHz. In this case, the 52-carrier can be a 52-tone RU defined in the conventional IEEE 802.11be / ax standard. The 52-carrier (e.g., 52-tone RU) can be duplicated in the frequency domain. For example, four 52-carriers can be mapped / allocated in the frequency domain, and these four 52-carriers can be duplicated RUs. In other words, any one of the four 52-carriers can be a duplicate / repetition of another one.

[0157] Figure 15 illustrates an example of duplicating wireless resources related to the data fields of the present specification. As illustrated, four 52-carrier / subcarriers (1510, 1520, 1530, 1540) may be arranged / mapped on the frequency domain. For example, the 52-carrier / subcarrier may be a 52-tone RU defined in the conventional IEEE 802.11be / ax standard. For example, the second to fourth 52-carrier / subcarriers (1520, 1530, 1540) may be duplicates or repetitions of the first 52-carrier / subcarrier (1510). As illustrated, the four 52-carrier / subcarriers (1510, 1520, 1530, 1540) may be arranged sequentially on the frequency domain. Sequentially arranged may mean that the lowest frequency / subcarrier index is assigned to the first 52-carrier / subcarrier (1510), the highest frequency / subcarrier index is assigned to the fourth 52-carrier / subcarrier (1540), etc. For example, at least one Null-carrier / tone / signal may be included between the four sequentially arranged 52-carrier / subcarriers (1510, 1520, 1530, 1540). For example, unused carriers / subcarriers (e.g., two not used carriers as shown in FIG. 15) and / or directed current (DC) signals (e.g., 7-DC corresponding to 7 tones as shown in FIG. 15) may be included between the four sequentially arranged 52-carrier / subcarriers (1510, 1520, 1530, 1540).

[0158] For example, when transmitting data using only 52-tone RU within 20 MHz as in the example of Fig. 15, an LTF signal with boosted power can be transmitted only for the portion where data is carried. However, when this technical feature is applied, the PAPR of the ELR-LTF field may increase. Therefore, in order to lower the PAPR of the ELR-LTF field during ELR transmission, the ELR-LTF sequence can be configured as follows.

[0159] For example, the LTF proposed in this specification can be called by various names. For example, it can be called by various names such as ELR / LR / ER-LTF. For example, it can be called by various names such as UHR / MU / SU-LTF. For example, it can be called by various names such as 1st / 2nd / TX / RX-LTF.

[0160] For example, the LTF (signal) of the present specification can be generated based on an LTF sequence. For example, the LTF sequence can include a preset number of elements (or values, etc.), and the elements can have a value of 1 or -1. For example, a sequence having a length of 26 can be a sequence including 26 elements. The sequence can be called by various names such as an M sequence, an LTF sequence, an ELR LTF sequence, a first sequence, etc.

[0161] For example, the ELR LTF sequence of the present specification can be composed of a combination of the following eight M sequences each having a length of 26. In other words, the LTF sequence of the present specification can be composed / defined based on at least one of M_seq(1) to M_seq(8).

[0162] [Formula 1]

[0163] M_seq(1) = {-1, +1, -1, +1, -1, +1, +1, +1, -1, +1, +1, +1, -1, -1, +1, -1, -1, -1, -1, -1, +1, +1, -1, -1, -1, -1}

[0164] M_seq(2) = {+1, +1, -1, +1, -1, +1, +1, +1, +1, -1, +1, -1, -1, +1, +1, -1, +1, +1, +1, +1, -1, -1, +1, -1, -1, -1}

[0165] M_seq(3) = {-1, -1, -1, -1, +1, +1, +1, -1, -1, -1, +1, -1, +1, -1, +1, -1, +1, +1, -1, +1, +1, +1, -1, -1, +1, -1}

[0166] M_seq(4) = {+1, +1, +1, +1, -1, +1, +1, -1, -1, +1, -1, +1, -1, +1, -1, -1, +1, -1, +1, +1, +1, -1, -1, +1, +1, +1}

[0167] M_seq(5) = {+1, +1, +1, +1, -1, +1, +1, -1, -1, +1, -1, +1, +1, +1, +1, +1, -1, +1, -1, -1, -1, +1, +1, -1, -1, -1}

[0168] M_seq(6) = {+1, +1, +1, +1, +1, +1, -1, +1, +1, +1, -1, +1, +1, -1, -1, -1, +1, -1, +1, -1, -1, +1, +1, -1, +1, -1}

[0169] M_seq(7)= {+1, +1, +1, +1, -1, -1, +1, +1, +1, +1, +1, -1, +1, +1, -1, -1, -1, +1, -1, -1, -1, +1, -1, +1, -1, +1}

[0170] M_seq(8) = {+1, -1, +1, -1, +1, +1, +1, +1, -1, -1, -1, +1, +1, +1, +1, +1, +1, +1, +1, -1, +1, -1, -1, +1, +1, -1}

[0171] For example, if the data field is repeated or duplicated in units of 5 carriers / tones / subcarriers, the LTF (e.g., ELR-LTF) may be composed of a sequence having a length of 52. In this case, the sequence having a length of 52 may be composed based on at least one of the M sequences of length 26 described in Equation 1 (e.g., a combination of the M sequences described in Equation 1).

[0172] For example, a length 52 sequence with lower PAPR for LTF (e.g., ELT-LTF) can be generated / constructed based on a combination of two different M sequences.

[0173] For example, a length 52 sequence formed to have low PAPR can be composed of the following combinations.

[0174] [Formula 2]

[0175] 52 sequence_1 = [M_seq(4), M_seq(5)]

[0176] The sequence of Equation 2 can be expressed as Equation 3 below.

[0177] [Formula 3]

[0178] {1, 1, 1, 1, -1, 1, 1, -1, -1, 1, -1, 1, -1, -1, 1, -1, -1, 1, -1, 1, -1, 1, 1, 1, 1, -1, -1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1, 1, 1, -1, -1, -1, 1, 1, -1, -1, -1}

[0179] For example, a length 52 sequence like the one below can also be defined.

[0180] [Formula 4]

[0181] 52 sequence_2 = [M_seq(5), M_seq(4)]

[0182] The sequence of Equation 4 can be expressed as Equation 5 below.

[0183] [Formula 5]

[0184] {1, 1, 1, 1, -1, 1, 1, -1, -1, 1, -1, 1, 1, 1, 1, 1, -1, 1, -1, -1, -1, 1, 1, -1, -1, -1, 1, 1, -1, -1, 1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, 1, -1, -1, 1, 1, 1, 1, -1, -1, 1, 1, 1}

[0185] An ELR-LTF sequence composed using the length 52 sequence (52 sequence_1 and / or 52 sequence_2) as above can be composed as follows.

[0186] For example, when using 52 sequence_1, it can be expressed as follows.

[0187] [Formula 6]

[0188] ELR-LTF sequence = [52 sequence_1, 52 sequence_1, 52 sequence_1, 52 sequence_1]

[0189] For example, when using 52 sequence_2, it can be expressed as follows.

[0190] [Formula 7]

[0191] ELR-LTF sequence = [52 sequence_2, 52 sequence_2, 52 sequence_2, 52 sequence_2]

[0192] For example, since the ELR-LTF sequence is composed of a repeated sequence of length 52 as described above, in order to lower the PAPR, the coefficient may be multiplied by 26 sequence units (e.g., 26 element units) for the sequence. In this case, the coefficient may be one (1) or minus one (-1).

[0193] For example, the ELR-LTF sequence of the present specification can be constructed using the proposed 52 sequence_1 and 52 sequence_2. In this case, the coefficient for the minimum PAPR for the 52 sequence can be constructed as follows.

[0194] For example, when constructing an ELR LTF sequence using 52 sequence_1, the coefficient applied to every 26 sequences (e.g., applied in units of 26 elements) can be defined as follows, and the PAPR value according to the coefficient is as follows.

[0195] [Formula 8]

[0196] Coefficient_1 = {1, -1, 1, -1, 1, 1, -1, -1}, PAPR = 2.9793

[0197] Coefficient_2 = {-1, 1, -1, 1, -1, -1, 1, 1}; PAPR = 2.9793

[0198] As described above, in the above formula, one coefficient can be applied to each sequence of length 26. For example, the first coefficient value (1) included in Coefficient_1 can be multiplied to the first 26-length sequence among the entire LTF sequence, and the second coefficient value (-1) included in Coefficient_1 can be multiplied to the second 26-length sequence among the entire LTF sequence.

[0199] For example, when constructing an ELR LTF sequence using 52 sequence_2, the coefficient applied to each 26 sequences can be defined as follows, and the PAPR value according to the coefficient is as follows.

[0200] [Formula 9]

[0201] Coefficient_a = {1, 1, -1, -1, 1, -1, 1, -1}, PAPR = 2.9809

[0202] Coefficient_b = {-1, -1, 1, 1, -1, 1, -1, 1}; PAPR = 2.9809

[0203] For example, similar to equation 8, the coefficient of equation 9 can be applied to each sequence with length 26 (e.g., applied in units of 26 elements).

[0204] Additionally or alternatively, the ELR LTF sequence can be constructed by forming 52 sequences with two different reverses (M_seq) using each M sequence constructed by applying reverse to the above M sequences, and constructing the ELR LTF sequence using these. In constructing the ELR-LTF sequence in this way, the 52 sequences for lowering the PAPR can be constructed as follows.

[0205] In other words, 52 sequence_1 and 52 sequence_2 of this specification can be transformed as in Equations 10 to 13 below.

[0206] [Formula 10]

[0207] 52 sequence_1 = [reverse(M_seq(4)), reverse(M_seq(5))]

[0208] The sequence of Equation 10 can be expressed as Equation 11 below.

[0209] [Formula 11]

[0210] {1, 1, 1, -1, -1, 1, 1, 1, -1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1, 1, -1, 1, -1, 1, 1, -1, 1, 1, -1, -1, 1, -1, -1, 1, -1, 1, 1, 1, -1, 1, 1, 1, -1, 1, -1, 1, 1, 1, 1, -1, 1, 1, 1, 1, 1}

[0211] [Formula 12]

[0212] 52 sequence_2 = [reverse(M_seq(5)), reverse(M_seq(4))]

[0213] The sequence of Equation 12 can be expressed as Equation 13 below.

[0214] [Formula 13]

[0215] {-1, -1, -1, 1, 1, -1, -1, -1, 1, -1, 1, 1, 1, 1, 1, -1, 1, -1, -1, 1, 1, -1, 1, -1, 1, 1, 1, 1, 1, 1, -1, -1, 1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, 1, 1, 1, 1}

[0216] Additionally or alternatively, an ELR-LTF sequence can be constructed using a sequence of length 52 constructed in the same manner as above to lower PAPR even when a new M sequence is constructed by multiplying each M sequence by minus one (-1).

[0217] When constructing an ELR-LTF sequence using a sequence of length 52 defined as above, the ELR-LTF can be constructed by applying a coefficient in units of sequences of length 26 (e.g., 26 element units) to lower the PAPR. At this time, the coefficient and the resulting PAPR according to the sequence of length 52 constituting the ELR-LTF are as follows.

[0218] For example, if a new M sequence is used by applying reverse or minus one (-1) to the M sequence, the same coefficient can be applied to all sequences of length 52 as follows.

[0219] For example, when applying Reverse M seq, the following technical characteristics can be applied to 52 sequence_1. For example, when constructing an ELR LTF sequence using 52 sequence_1, the coefficient applied to every 26 sequences (e.g., applied in units of 26 elements) can be defined as follows. In this case, the PAPR value according to the coefficient can be as follows.

[0220] [Formula 14]

[0221] Coefficient_1 = {1, -1, 1, -1, 1, 1, -1, -1}, PAPR = 2.9809

[0222] Coefficient_2 = {-1, 1, -1, 1, -1, -1, 1, 1}; PAPR = 2.9809

[0223] For example, similar to Equation 8, the coefficient of Equation 14 can be applied to each sequence with length 26 (e.g., applied in units of 26 elements).

[0224] For example, when applying Reverse M seq, the following technical characteristics can be applied to 52 sequence_2. For example, when constructing an ELR LTF sequence using 52 sequence_2, the coefficient applied to every 26 sequences (e.g., applied in units of 26 elements) can be defined as follows. In this case, the PAPR value according to the coefficient can be as follows.

[0225] [Formula 15]

[0226] Coefficient_a = {1, -1, 1, -1, 1, 1, -1, -1}, PAPR = 2.9793

[0227] Coefficient_b = {-1, 1, -1, 1, -1, -1, 1, 1}; PAPR = 2.9793

[0228] For example, similar to Equation 8, the coefficient of Equation 15 can be applied to each sequence with length 26 (e.g., applied in units of 26 elements).

[0229] For example, the coefficients for 52 sequence_1 and 52 sequence_2 constructed based on the M sequence set constructed by applying (-1)*M seq (specifically, multiplying by minus one) can be applied in the same manner as the coefficients above, and the PAPR values ​​accordingly can be as follows. In other words, 52 sequence_1 and 52 sequence_2 of the present specification can be transformed as in Equations 16 and 17 below, and the above-described coefficients can be applied to the corresponding sequences.

[0230] [Formula 16]

[0231] 52 sequence_1 = {-1, -1, -1, -1, 1, -1, -1, 1, 1, -1, 1, -1, 1, -1, 1, 1, -1, 1, -1, -1, -1, 1, 1, -1, -1, -1, -1, -1, -1, -1, 1, -1, -1, 1, 1, -1, 1, -1, -1, -1, -1, -1, 1, -1, 1, 1, 1, -1, -1, 1, 1, 1}, PAPR for coefficient 1 and coefficient 2 = 2.9793

[0232] [Formula 17]

[0233] 52 sequence_2 = {-1, -1, -1, -1, 1, -1, -1, 1, 1, -1, 1, -1, -1, -1, -1, -1, 1, -1, 1, 1, 1, -1, -1, 1, 1, 1, -1, -1, -1, -1, 1, -1, -1, 1, 1, -1, 1, -1, 1, -1, 1, 1, -1, 1, -1, -1, -1, 1, 1, -1, -1, -1}, PAPR for coefficient a and coefficient b = 2.9809

[0234] Additionally or alternatively, the ELR LTF can be constructed by generating 52 sequence_1 and 52 sequence_2 using M sequence_4 (specifically M_seq(4)) and M sequence_5 (M_seq(5)) described in Equation 1. When constructing 52 sequences by applying reverse to both M_seq(4) and M_seq(5) or multiplying by minus one (-1), the coefficient per 52 sequence applied to reduce PAPR can be applied in the same manner as above, and in this case, the PAPR is as follows.

[0235] For example, LTF sequences can be generated by applying reverse to M_seq(4) and Mseq(5). In this case, applying Coefficient_1 and Coefficient_2 to 52 sequence_1 yields a PAPR of 2.9809. Furthermore, applying Coefficient_a and Coefficient_b to 52 sequence_2 yields a PAPR of 2.9793.

[0236] For example, we can generate LTF sequences by multiplying M_seq(4) and Mseq(5) by minus one (-1). In this case, if we apply Coefficient_1 and Coefficient_2 to 52 sequence_1, we can obtain PAPR = 2.9793. Also, if we apply Coefficient_a and Coefficient_b to 52 sequence_2, we can obtain PAPR = 2.9809.

[0237] For example, a 52-length sequence corresponding to ELR-LTF as described above can be composed of {M_seq(4), M_seq(5)} or {M_seq(5), M_seq(4))}. In this case, it is also possible to generate a 52-length sequence by multiplying only one of M_seq(4) or M_seq(5) by reverse or minus one (-1). In this case, the following coefficient can be applied to lower the PAPR of the 52-length sequence, and through this, the PAPR can be lowered as follows.

[0238] For example, it is possible to apply reverse only to M_seq(4) as follows. That is, a sequence of length 52 can be composed of {reverse (M_seq(4)), M_seq(5)}. In this case, the PAPR can be 2.9930. An example of an applicable coefficient in this case can be expressed by the following formula.

[0239] [Formula 18]

[0240] Coefficient 3 = {-1, 1, -1, -1, 1, -1, -1, -1}

[0241] Coefficient 4 = {1, -1, 1, 1, -1, 1, 1, 1}

[0242] When a sequence of length 52 is composed of {M_seq(5), reverse (M_seq(4))}, the PAPR is 2.9813, and an example of the coefficient can be expressed by the formula below.

[0243] [Formula 19]

[0244] Coefficient 5 = {-1, -1, -1, -1, -1, 1, 1, -1}

[0245] Coefficient 6 = {1, 1, 1, 1, 1, -1, -1, 1}

[0246] Additionally or alternatively, an example of applying reverse only to M_seq(5) is possible. A detailed explanation is as follows. For example, if a 52-length sequence consists of {(M_seq(4)), reverse (M_seq(5))}, the PAPR can be 2.9813. An example of an applicable coefficient in this case can be expressed by the following formula.

[0247] [Formula 20]

[0248] Coefficient 7 = {-1, 1, 1, -1, -1, -1, -1, -1}

[0249] Coefficient 8 = {1, -1, -1, 1, 1, 1, 1, 1}

[0250] For example, if a sequence of length 52 is composed of {reverse (M_seq(5)), (M_seq(4))}, the PAPR can be 2.9930. An example of an applicable coefficient in this case can be expressed by the formula below.

[0251] [Formula 21]

[0252] Coefficient 9 = {-1, -1, -1, 1, -1, -1, 1, -1}

[0253] Coefficient 10 = {1, 1, 1, -1, 1, 1, -1, 1}

[0254] Additionally or alternatively, it is also possible to construct an LTF sequence by multiplying M_seq(4) by minus one (-1). For example, if a sequence of length 52 is composed of {(M_seq(4))*(-1), M_seq(5)}, the PAPR can be 2.9793. The Coefficients applied to the sequence can be Coefficient 5 and Coefficient 6 defined above. For example, if a sequence of length 52 is composed of {M_seq(5), (M_seq(4))*(-1)}, the PAPR can be 2.9809. The Coefficients applied to the sequence can be defined as Coefficient 7 and Coefficient 8 defined above.

[0255] Additionally or alternatively, if M_seq(5) is multiplied by minus one (-1), the coefficient according to the composition of the sequence of length 52 can be determined in the same way as multiplying M_seq(4) by minus one (-1). In this case, the PAPR can be the same as multiplying M_seq(4) by minus one (-1).

[0256] The above-described technical features (e.g., mathematical formulas related to LTF signals / sequences) can be applied to various types of PPDUs. Below, an example of applying the above-described technical features to an ELR PPDU is described.

[0257] Fig. 16 illustrates an example of an ELR PPDU of the present specification. As illustrated, an ELR PPDU (or a PPDU used for ELR communication) may include L-STF (1605), L-LTF (1610), L-SIG (1615), RL-SIG (1620), U-SIG (1625), ELR-MARK (1630), UHR-STF (1635), UHR-LTF (1640), ELR-SIG (1645), and Data (1650). For example, some fields of Fig. 16 may be omitted. For example, the order of some fields of Fig. 16 may be changed differently. Each field disclosed in Fig. 16 may be called by various names such as signal / bit.

[0258] The value of the number of spatial streams (e.g., Nss) for the above ELR PPDU may be limited to 1. Additionally or alternatively, for example, the ELR PPDU has a fixed bandwidth of 20 MHz and can be used for both downlink and uplink in 2.4 GHz band operation, but can be used only for uplink in 5 GHz and 6 GHz band operation. In other words, the ELR PPDU may consist of only 20 MHz and may not have bandwidths such as 40 / 80 / 160 / 320 MHz.

[0259] For example, the ELR-MARK (1630) of FIG. 16 may be composed of two OFDM symbols. The ELR-MARK (1630) may include information about an identifier (e.g., BSS_COLOR) indicating the BSS color to which the STA transmitting the corresponding PPDU belongs.

[0260] For example, the U-SIG (1625) may have the following characteristics. For example, the U-SIG (1625) of the present specification may be composed of signals / fields for an ELR PPDU. For example, a PPDU other than an ELR PPDU (e.g., a UHR MU PPDU or a UHR TB PPDU) also contains a U-SIG, but the contents of the U-SIG (1625) of the present specification may contain different contents.

[0261] For example, the U-SIG (1625) of the present specification has a length of 2 symbols, and each symbol can be represented as U-SIG-1 and U-SIG-2. For example, the B0 bit to the B2 bit of the U-SIG-1 can have various names such as the first information described above or the PHY Version Identifier, and can include a value (e.g., a value of 1) that identifies that the PHY version of the PPDU is UHR. For example, the positions of the B0 bit to the B2 bit can be changed.

[0262] Additionally or alternatively, the B3 bits to the B5 bits of the U-SIG-1 may have various names such as the second information or the BW information, and may include information regarding the bandwidth of the ELR PPDU. For example, the B3 bits to the B5 bits of the U-SIG-1 may only have a value of 0. This is because the bandwidth of the ELR PPDU is preferably fixed to 20 MHz. For example, the positions of the B3 bits to the B5 bits may be changed.

[0263] Additionally or alternatively, the B6 bit of the U-SIG-1 may contain information regarding whether the PPDU is transmitted in the UL or DL. For example, the position of the B6 bit may be changed.

[0264] Additionally or alternatively, bits B7 to B12 of U-SIG-1 may indicate the ID of a Basic Service Set (BSS). For example, bits B7 to B12 may include ID information (or BSS color information) of a BSS to which an STA transmitting / receiving the corresponding PPDU belongs. For example, the positions of bits B7 to B12 may be changed.

[0265] Additionally or alternatively, bits B13 to B19 of U-SIG-1 may contain information related to the duration of a transmission opportunity (TXOP). For example, the positions of bits B13 to B19 may be changed.

[0266] Additionally or alternatively, bits B20 through B24 of U-SIG-1 may all be set to 1, and the bits may be referred to as disregard. For example, the positions of bits B20 through B24 may be changed.

[0267] Additionally or alternatively, the B25 bit of U-SIG-1 may be set to 1, and the bit may be called Validate. For example, the position of the B25 bit may be changed.

[0268] Additionally or alternatively, the B0 bit and the B1 bit of the U-SIG-2 may have various names such as the third information or PPDU Type And Compression Mode. The B0 bit and the B1 bit may always have a value of 3 regardless of whether the related PPDU is a DL PPDU or an UL PPDU, thereby indicating / identifying that the PPDU is an ELR PPDU. For example, the positions of the B0 bit and the B1 bit may be changed.

[0269] Additionally or alternatively, bits B2 to B12 of U-SIG-2 may be configured as an STA ID. For example, bits B2 to B12 may be configured as a portion of 11 bits (e.g., 11 bits of the LSB or 11 bits of the MSB) of the Association ID (AID) of the STA transmitting the corresponding PPDU. For example, the positions of bits B2 to B12 may be changed.

[0270] Additionally or alternatively, bits B13 to B15 of U-SIG-2 may be configured as ER / ELR validate. These three bits may be used to identify an ELR PPDU, and these three bits may all be set to 1 (i.e., these three bits have a value of 7). For example, the positions of bits B13 to B15 may be changed.

[0271] Additionally or alternatively, bits B16 to B19 of the U-SIG-2 may be configured as a CRC.

[0272] Additionally or alternatively, bits B20 through B25 of U-SIG-2 may be configured as a tail, such that all bits are zero.

[0273] For example, ELR-SIG (1645) may have the following characteristics. For example, ELR-SIG (1645) of the present specification may have two parts. Each part may be represented as ELR-SIG-1 and ELR-SIG-2. For example, the B0 bit of ELR-SIG-1 may include the above-described first ER / ELR-SIG information or ELR Version Identifier. For example, the B0 bit of ELR-SIG-1 may have information for identifying an ELR version, and the ELR Version Identifier included in an ELR PPDU having the technical characteristics described in the present specification may have a value of 0. For example, the position of the B0 bit may be changed.

[0274] Additionally or alternatively, the B1 bit of the ELR-SIG-1 may include a UL / DL field. For example, the bit may include information regarding whether the ELR PPDU is transmitted in UL / DL. For example, the position of the B1 bit may be changed.

[0275] Additionally or alternatively, the B2 bit of the ELR-SIG-1 may include an MCS field. For example, the bit may include information related to MCS information applied to a data field of an ELR PPDU. For example, when the bit is set to a first value (e.g., 0), the bit may indicate that BPSK with a coding rate of 1 / 2 is applied to the data field of the ELR PPDU. For example, when the bit is set to a second value (e.g., 1), the bit may indicate that QPSK with a coding rate of 1 / 2 is applied to the data field of the ELR PPDU. For example, the position of the B2 may be changed.

[0276] Additionally or alternatively, the B3 bit of the ELR-SIG-1 may include a coding (type) field. For example, the bit may include information related to coding (type) information applied to a data field of the ELR PPDU. For example, when the bit is set to a first value (e.g., 0), the bit may indicate that the BCC technique is applied to the data field of the ELR PPDU. For example, when the bit is set to a second value (e.g., 1), the bit may indicate that the LDPC technique (e.g., LDPC with a word length of 648, 1296, or 1944) is applied to the data field of the ELR PPDU.

[0277] Additionally or alternatively, bits B4 to B12 of the ELR-SIG-1 may include a length field. For example, the length field may have a length of 9 bits, and the specific bit positions may be changed. For example, the field may include information regarding the number of symbols in the data field included in the ELR PPDU.

[0278] Additionally or alternatively, the B13 bit of the ELR-SIG-1 may contain information regarding the presence of an LDPC extra (OFDM) symbol. For example, the information may include information regarding whether additional OFDM symbols are required for LDPC encoding of the PPDU.

[0279] Additionally or alternatively, bits B14 to B17 of ELR-SIG-1 may contain CRC bits, and bits B18 to B23 of ELR-SIG-1 may contain tail bits and have a value of 0.

[0280] Additionally or alternatively, bits B0 to B10 of the ELR-SIG-2 may contain information regarding the STA-ID. For example, these bits may be composed of a portion of 11 bits (e.g., 11 bits of the LSB or 11 bits of the MSB) of the AID of the STA transmitting the ELR PPDU. For example, the positions of these bits may be changed.

[0281] Additionally or alternatively, bits B1 through B13 of the ELR-SIG-2 may contain a disregard field / information. Each bit of the 3-bit field / information may be set to 1.

[0282] Additionally or alternatively, bits B14 to B17 of ELR-SIG-2 may contain CRC bits, and bits B18 to B23 of ELR-SIG-1 may contain tail bits and have a value of 0.

[0283] For example, the Data (1650) field may be called by various names such as ER / ELR-Data, Payload, etc. The Data (1650) field and / or ELR-SIG (1645) of this specification may be applied as an example of FIG. 16.

[0284] For example, the UHR-LTF (1640) can be configured / generated based on the above-described LTF sequence. For example, the UHR-LTF (1640) can be generated based on an LTF sequence based on Equation 6 or Equation 7. The Equation 6 or Equation 7 can be multiplied by at least one coefficient based on Equation 8 or Equation 9. Additionally or alternatively, the UHR-LTF (1640) can be generated based on an LTF sequence based on Equation 10 or Equation 12. The Equation 10 or Equation 12 can be multiplied by at least one coefficient based on Equation 14 or Equation 15. For example, the LTF sequence related to the UHR-LTF (1640) can be modified in various ways. For example, the LTF sequence can be designed in various ways, such as Equation 16, Equation 17, etc. Additionally, the LTF sequence of this specification can be multiplied by various coefficients such as Equations 19 to 21.

[0285] Figure 17 is an example of a procedure flowchart related to the present specification. The procedure illustrated in Figure 17 may be performed by a non-AP STA, a non-AP MLD, an AP (Access Point), or an AP MLD (AP Multi-link Device).

[0286] As illustrated in S1710, an STA (e.g., non-AP or AP) can generate (or configure, construct) a PPDU. For example, the PPDU of step S1710 can be a PPDU of various types / formats. For example, the PPDU of step S1710 can be a PPDU related to ELR communication, a PPDU unrelated to ELR communication, or a PPDU related to SU / MU / NDP.

[0287] The PPDU of step S1710 may include a data field. Additionally or alternatively, the PPDU of step S1710 may include a signal field containing information necessary for interpreting the data field (or the PPDU). The signal field may have various names. For example, the signal field may have various names such as ELR-SIG, UHR-SIG, control signal field, first / second signal field, transmission signal field, etc.

[0288] For example, the PPDU of step S1710 may have a bandwidth of 20 MHz. For example, the bandwidth of the PPDU may have various bandwidths such as 40 / 80 / 160 MHz.

[0289] For example, the data field (or signal field) of the PPDU may include four first carrier units duplicated in the frequency domain in units of first carrier units having multiple tones. For example, the first carrier unit unit may have 52 subcarriers / carriers / tones.

[0290] In other words, the data field may be transmitted through four 52-tone resource units (RUs) that are duplicated in the frequency domain in units of 52-tone RUs. For example, the four 52-tone RUs may include a first RU (e.g., first 52-tone RU), a second RU (e.g., second 52-tone RU), a third RU (e.g., third 52-tone RU), and a fourth RU (e.g., fourth 52-tone RU) that are sequentially positioned in the frequency domain.

[0291] For example, the PPDU of step S1710 may include an LTF. For example, the LTF may be generated based on an LTF sequence corresponding to the first RU, the second RU, the third RU, and the fourth RU.

[0292] For example, the sequence of Equation 6 (or various sequences described in Equation 7, etc.) may correspond to a first LTF sequence corresponding to the first RU, a second LTF sequence corresponding to the second RU, a third LTF sequence corresponding to the third RU, and a fourth LTF sequence corresponding to the fourth RU. The first to fourth LTF sequences may be multiplied by a coefficient proposed in the present specification (e.g., a coefficient of Equation 8 or Equation 9). The coefficient may be called by various names, such as a first / second coefficient.

[0293] For example, as in the sequence of Equation 6, the first to fourth sequences may all be determined as the same single sequence (e.g., 52 sequence_1). In this case, the first to fourth sequences may be multiplied by various coefficients revealed in Equation 8, etc. For example, as in Equation 8, the first RU may be multiplied by a coefficient of {1, -1}, the second RU may be multiplied by a coefficient of {1, -1}, the third RU may be multiplied by a coefficient of {1, 1}, and the fourth RU may be multiplied by a coefficient of {-1, -1}. In other words, the first 26 elements of the first sequence (e.g., 52 sequence_1) may be multiplied by a coefficient of one (1), and the next 26 elements may be multiplied by a coefficient of minus one (-1). Also, for the second sequence corresponding to the second RU, the first 26 elements of the first sequence (e.g., 52 sequence_1) may be multiplied by a coefficient of one (1), and the next 26 elements may be multiplied by a coefficient of minus one (-1). Also, for the third sequence corresponding to the third RU, the first 26 elements of the first sequence (e.g., 52 sequence_1) may be multiplied by a coefficient of one (1), and the next 26 elements may be multiplied by a coefficient of one (1). Also, for the fourth sequence corresponding to the fourth RU, the first 26 elements of the first sequence (e.g., 52 sequence_1) may be multiplied by a coefficient of Manius one (-1), and the next 26 elements may be multiplied by a coefficient of minus one (-1).

[0294] The above-described example relates to Coefficient_1 of Equation 6 and Equation 8. However, the example of the present specification is not limited by Equation 6 and / or Equation 8, etc. For example, even if the sequence of Equation 6 is used, Coefficient_2 of Equation 8, etc. may be applied. For example, a sequence such as Equation 7 may be used instead of the sequence of Equation 6. For example, various Coefficients of Equation 9 may be used together with Equation 7. In addition, various sequences such as Equation 10 to Equation 13 may be used. In this case, various Coefficients such as Equation 14 to Equation 15 may be used. In addition, various sequences such as Equation 16 to Equation 17 may be used. In addition, various sequences such as Equation 18 to Equation 21 may be used.

[0295] For convenience of explanation, a specific LTF sequence is described in this specification as being multiplied by at least one coefficient (i.e., multiplying two equations) in the first sequence, etc. However, a related LTF sequence can be expressed using only a single equation (e.g., a final equation multiplied by a coefficient). This representation does not alter the technical features of this specification.

[0296] As illustrated in step S1720, an STA (e.g., non-AP or AP) can transmit a PPDU. In other words, the STA can transmit a PPDU generated according to step S1710.

[0297] Figure 18 is an example of a procedure flowchart related to this specification. The procedure illustrated in Figure 18 may be performed by a non-AP STA, a non-AP MLD, an AP (Access Point), or an AP MLD (AP Multi-link Device).

[0298] As illustrated in S1810, an STA (e.g., non-AP or AP) may receive a PPDU. The PPDU received via S1910 may be identical to the PPDU generated according to S1710.

[0299] As illustrated in S1820, an STA (e.g., non-AP or AP) can decode a PPDU. The PPDU can include at least one signal field, and the signal field can include information for interpreting the PPDU (or data field). The STA can decode or interpret the PPDU based on the signal field.

[0300] The technical features of the present disclosure may be implemented by various devices. The devices of the present disclosure may be the devices described in FIG. 1 / FIG. 14. The devices of the present disclosure may include at least one processor; and at least one computer memory operably connectable to the at least one processor, the computer memory storing instructions for performing operations based on execution by the at least one processor.

[0301] For example, the processor may be a processor described in FIG. 1 and / or FIG. 14. That is, as described above, the processor of the present specification may include at least one of a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), and a modem (modulator and demodulator). The processor may include not only computers having various architectures such as single / multiprocessor architecture, sequential (Von Neumann) / parallel architecture, but also specialized circuits such as FPGAs, ASICs, signal processing devices, and other devices. For example, the processor of the present specification may be a SNAPDRAGON® series processor manufactured by Qualcomm®, an EXYNOS® series processor manufactured by Samsung®, an A series processor manufactured by Apple®, a HELIO® series processor manufactured by MediaTek®, an ATOM® series processor manufactured by INTEL®, or a processor that enhances the same.

[0302] For example, the instructions may refer to computer program instructions executed by the at least one processor. The (computer program) instructions provide logic and / or routines that enable the technical features of the present specification to be performed by the processor. The at least one processor can load and execute a computer program by reading the at least one memory.

[0303] The computer program(s) defined by the above instructions may be delivered to the device (e.g., STA) of the present specification via an appropriate delivery mechanism. The delivery mechanism may be, for example, a computer-readable storage medium, a computer program product, a memory device, a recording medium such as a CD-ROM or DVD, or a product tangibly embodying the computer program. The delivery mechanism may be a signal configured to reliably transmit the computer program via a wireless or electrical connection.

[0304] The above (computer program) instructions may include software or firmware for a programmable processor (e.g., programmable content of a hardware device whether instructions for a processor, or configuration settings for a fixed-function device, gate array or programmable logic device, etc.).

[0305] For example, the memory may be the memory described in FIG. 1 and / or FIG. 14. That is, as described above, the memory of the present specification may store control information related to the operation of the STA of the present specification or information about signals transmitted and received by the STA (e.g., PPDU including management / control / data frames).

[0306] The technical features of this specification may be implemented in at least one computer-readable recording medium (CRM). The CRM includes instructions that are executed by at least one processor as described above. The instructions stored in the CRM may be computer program instructions as described above.

[0307] The device of the present disclosure may further include a transceiver. The transceiver may be operably connectable to the memory / processor, etc. The transceiver may be the transceiver illustrated in FIG. 1 and / or FIG. 14.

[0308] The technical features of this specification described above are applicable to various applications and business models. For example, the technical features described above can be applied to wireless communication in devices that support artificial intelligence (AI).

[0309] Artificial intelligence (AI) is the study of artificial intelligence or the methodologies for creating it, while machine learning (ML) defines various problems in the field of AI and studies the methodologies for solving them. Machine learning is also defined as an algorithm that improves performance on a task through consistent experience.

[0310] An artificial neural network (ANN) is a model used in machine learning. It can refer to a model with problem-solving capabilities, consisting of artificial neurons (nodes) formed by the connection of synapses to form a network. An ANN can be defined by the connection patterns between neurons in different layers, the learning process that updates model parameters, and the activation function that generates output values.

[0311] An artificial neural network may include an input layer, an output layer, and optionally one or more hidden layers. Each layer contains one or more neurons, and the artificial neural network may include synapses connecting neurons. In an artificial neural network, each neuron can output a function value of an activation function based on input signals, weights, and biases received through the synapses.

[0312] Model parameters are parameters determined through learning, including synaptic connection weights and neuron biases. Hyperparameters are parameters that must be set before learning in machine learning algorithms, including the learning rate, number of iterations, mini-batch size, and initialization function.

[0313] The goal of artificial neural network training can be seen as determining model parameters that minimize a loss function. The loss function can be used as an indicator for determining optimal model parameters during the artificial neural network training process.

[0314] Machine learning can be classified into supervised learning, unsupervised learning, and reinforcement learning depending on the learning method.

[0315] Supervised learning refers to a method for training an artificial neural network when given labels for the training data. The labels can refer to the correct answer (or output value) that the artificial neural network must infer when the training data is input to the artificial neural network. Unsupervised learning can refer to a method for training an artificial neural network when the training data is not given labels. Reinforcement learning can refer to a learning method in which an agent defined within a given environment is trained to select actions or action sequences that maximize the cumulative reward in each state.

[0316] Machine learning implemented with a deep neural network (DNN) containing multiple hidden layers among artificial neural networks is also called deep learning, and deep learning is a subset of machine learning. Hereinafter, the term "machine learning" is used to encompass deep learning.

[0317] Additionally, the above-described technical features can be applied to wireless communication of robots.

[0318] A robot can be defined as a machine that automatically performs or operates a given task based on its own capabilities. Specifically, a robot capable of perceiving its environment, making independent judgments, and performing actions can be called an intelligent robot.

[0319] Robots can be categorized into industrial, medical, household, and military applications based on their intended use or field. Robots are equipped with actuators or motors, enabling them to perform various physical actions, such as moving robot joints. Furthermore, mobile robots incorporate wheels, brakes, and propellers into their actuators, enabling them to move on the ground or fly in the air.

[0320] Additionally, the above-described technical features can be applied to devices that support extended reality.

[0321] Extended reality is a general term for virtual reality (VR), augmented reality (AR), and mixed reality (MR). VR technology presents real-world objects and backgrounds as CG images only, AR technology presents virtual CG images over images of real objects, and MR technology is a computer graphics technology that blends and combines virtual objects with the real world.

[0322] MR technology is similar to AR in that it presents both real and virtual objects simultaneously. However, while AR uses virtual objects to complement real objects, MR uses virtual and real objects on an equal footing.

[0323] XR technology can be applied to HMD (Head-Mount Display), HUD (Head-Up Display), mobile phones, tablet PCs, laptops, desktops, TVs, digital signage, etc., and devices to which XR technology is applied can be called XR devices.

Claims

1. Configure the LTF (Long Training Field) and data fields included in the PPDU (Physical Protocol Data Unit). The bandwidth of the above PPDU is 20 MHz, The above data field is transmitted in the frequency domain in units of 52-tone RU (resource unit) through four duplicated 52-tone RUs, The above four 52-tone RUs include a first RU, a second RU, a third RU, and a fourth RU, which are sequentially positioned in the frequency domain, The LTF corresponding to the above first RU is generated based on the LTF sequence, The above LTF sequence comprises a sequence in which a first sequence including 52 elements is multiplied by at least one first coefficient, The first sequence is {1, 1, 1, 1, -1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1, 1, -1, 1, -1, 1, -1, 1, 1, 1, -1, -1, 1, 1, 1, 1, 1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1, 1, -1, -1, 1, -1, -1, -1}, step; and Step of transmitting the above PPDU How to include.

2. In the first paragraph, the first 26 elements of the first sequence are multiplied by a coefficient of one (1), and the next 26 elements are multiplied by a coefficient of minus one (-1). method.

3. In the first paragraph, the first 26 elements of the first sequence are multiplied by a coefficient of minus one (-1), and the next 26 elements are multiplied by a coefficient of one (1). method.

4. In paragraph 1, The LTF corresponding to the second RU is formed based on a second sequence in which at least one second coefficient is multiplied by the first sequence, The second coefficient is determined as one (1) for the first 26 elements and as minus one (-1) for the next 26 elements. method.

5. In paragraph 1, The LTF corresponding to the third RU is formed based on a third sequence in which at least one third coefficient is multiplied by the first sequence, The third coefficient is determined as one (1) for the first 26 elements and one (1) for the next 26 elements. method.

6. In paragraph 1, The LTF corresponding to the fourth RU is formed based on a fourth sequence in which at least one fourth coefficient is multiplied by the first sequence, The fourth coefficient is determined as minus one (-1) for the first 26 elements and as minus one (-1) for the next 26 elements. method.

7. In paragraph 1, The above PPDU further includes an ELR (enhanced long range) signal field. method.

8. At least one processor; and At least one computer memory operable to said at least one processor, said memory storing instructions for performing operations based on being executed by said at least one processor, The instructions of at least one computer memory are: Configure the LTF (Long Training Field) and data fields included in the PPDU (Physical Protocol Data Unit), The bandwidth of the above PPDU is 20 MHz, The above data field is transmitted in the frequency domain in units of 52-tone RU (resource unit) through four duplicated 52-tone RUs, The above four 52-tone RUs include a first RU, a second RU, a third RU, and a fourth RU, which are sequentially positioned in the frequency domain, The LTF corresponding to the above first RU is generated based on the LTF sequence, The above LTF sequence comprises a sequence in which a first sequence including 52 elements is multiplied by at least one first coefficient, The first sequence is {1, 1, 1, 1, -1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1, 1, -1, 1, -1, 1, -1, 1, 1, 1, -1, -1, 1, 1, 1, 1, 1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1, 1, -1, -1, 1, -1, -1, -1}, step; and Step of transmitting the above PPDU Performing actions that include STA(station).

9. In paragraph 8, The instructions of at least one computer memory are: Configured to perform any one of the 2nd to 7th clauses STA.

10. Receive a PPDU (Physical Protocol Data Unit) including an LTF (Long Training Field) and a data field by the STA (station). The bandwidth of the above PPDU is 20 MHz, The above data field is transmitted in the frequency domain in units of 52-tone RU (resource unit) through four duplicated 52-tone RUs, The above four 52-tone RUs include a first RU, a second RU, a third RU, and a fourth RU, which are sequentially positioned in the frequency domain, The LTF corresponding to the above first RU is generated based on the LTF sequence, The above LTF sequence comprises a sequence in which a first sequence including 52 elements is multiplied by at least one first coefficient, The first sequence is {1, 1, 1, 1, -1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1, 1, -1, 1, -1, 1, -1, 1, 1, 1, -1, -1, 1, 1, 1, 1, 1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1, 1, -1, -1, 1, -1, -1, -1}, step; and A step of decoding the PPDU by the STA Including method.

11. In paragraph 10, The above STA performs any one of the second to seventh clauses. method.

12. At least one processor; and At least one computer memory operable to said at least one processor, said memory storing instructions for performing operations based on being executed by said at least one processor, The instructions of at least one computer memory are: Receive a PPDU (Physical Protocol Data Unit) containing a LTF (Long Training Field) and a data field, The bandwidth of the above PPDU is 20 MHz, The above data field is transmitted in the frequency domain in units of 52-tone RU (resource unit) through four duplicated 52-tone RUs, The above four 52-tone RUs include a first RU, a second RU, a third RU, and a fourth RU, which are sequentially positioned in the frequency domain, The LTF corresponding to the above first RU is generated based on the LTF sequence, The above LTF sequence comprises a sequence in which a first sequence including 52 elements is multiplied by at least one first coefficient, The first sequence is {1, 1, 1, 1, -1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1, 1, -1, 1, -1, 1, -1, 1, 1, 1, -1, -1, 1, 1, 1, 1, 1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1, 1, -1, -1, 1, -1, -1, -1}, step; and Step of decoding the above PPDU Performing actions that include STA(station).

13. In paragraph 12, The instructions of at least one computer memory are: Configured to perform any one of the 2nd to 7th clauses STA.

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