Wireless communication terminal and method for transmitting or receiving data in wireless communication system

Abstract

Disclosed are a wireless communication terminal and a method for transmitting or receiving data in a wireless communication system. A method for transmitting and receiving a TB PPDU based on a trigger frame in a wireless communication system. A terminal receives a trigger frame from an access point (AP), and transmits a response frame in response to the trigger frame. The response frame may be generated based on information obtained from the first plurality of spatial reuse fields or the second plurality of spatial reuse fields of the trigger frame according to a format and / or a resource unit of the response frame.

Description

[0001] This application is a divisional application of a patent application with application number 202180021148.1 (PCT / KR2021 / 003186), which was submitted to the China Patent Office on September 14, 2022, with an international application date of March 15, 2021, and the invention name is “Wireless communication terminal and method for sending or receiving data in a wireless communication system”. Technical Field

[0002] The present invention relates to a wireless communication system, and more particularly, to a method and apparatus for sending / receiving and configuring a trigger frame for indicating a trigger-based (TB) physical layer protocol data unit (PPDU) and a TB PPDU based on the trigger frame in the wireless communication system. Background Art

[0003] In recent years, as the supply of mobile devices has expanded, wireless LAN technology that can provide fast wireless Internet services to mobile devices has received attention. Wireless LAN technology allows mobile devices including smart phones, smart tablets, laptops, portable multimedia players, embedded devices, etc. to wirelessly access the Internet in homes or companies or specific service provision areas based on short-range wireless communication technology.

[0004] Since the use of 2.4GHz frequency to support the initial wireless LAN technology, the Institute of Electrical and Electronics Engineers (IEEE) 802.11 has been commercialized or developed various technical standards. First, IEEE 802.11b supports a maximum communication speed of 11Mbps when using the frequency of the 2.4GHz band. Compared with the frequency of the 2.4GHz band that is significantly congested, the IEEE 802.11a commercialized after IEEE802.11b uses a frequency of the 5GHz band instead of the 2.4GHz band to reduce the impact of interference, and by using OFDM technology, the communication speed is increased to a maximum of 54Mbps. However, the disadvantage of IEEE 802.11a is that the communication distance is shorter than that of IEEE 802.11b. In addition, similar to IEEE 802.11b, IEEE 802.11g uses the frequency of the 2.4GHz band to achieve a maximum communication speed of 54Mbps and meets backward compatibility to significantly cause concern, and further, in terms of communication distance, it is superior to IEEE 802.11a.

[0005] In addition, as a technical standard established to overcome the limitation of communication speed pointed out as a weakness in wireless LAN, IEEE 802.11n has been provided. IEEE 802.11n aims to improve the speed and reliability of the network and extend the working distance of the wireless network. In more detail, IEEE 802.11n supports high throughput (HT), wherein the data processing speed is a maximum of 540Mbps or higher, and further, based on multiple input and multiple output (MIMO) technology, wherein multiple antennas are used on both sides of the transmitting unit and the receiving unit to minimize transmission errors and optimize data speed. In addition, the standard can use a coding scheme that sends multiple copies superimposed on each other in order to increase data reliability.

[0006] With the provision of activated wireless LANs, and further, with the diversification of applications using wireless LANs, the demand for new wireless LAN systems supporting higher throughput (very high throughput (VHT)) than the data processing speed supported by IEEE 802.11n has attracted attention. Among them, IEEE 802.11ac supports a wide bandwidth (80 to 160 MHz) in the 5 GHz frequency. The IEEE 802.11ac standard is defined only in the 5 GHz band, but the initial 11ac chipset even supports operation in the 2.4 GHz band for backward compatibility with existing 2.4 GHz band products. In theory, according to the standard, the wireless LAN speed of multiple stations can be enabled to reach a minimum of 1 Gbps, and the maximum single link speed can be enabled to reach a minimum of 500 Mbps. This is achieved by extending the concept of the wireless interface accepted by 802.11n, such as a wider wireless frequency bandwidth (maximum 160 MHz), more MIMO spatial streams (maximum 8), multi-user MIMO, and high-density modulation (maximum 256 QAM). In addition, as a scheme for transmitting data by using a 60 GHz band instead of the existing 2.4 GHz / 5 GHz, IEEE 802.11ad has been provided. IEEE 802.11ad is a transmission standard that provides a maximum speed of 7 Gbps by using a beamforming technology, and is suitable for high bit rate moving image streams such as large-scale data or non-compressed HD video. However, since the 60 GHz band is difficult to pass through obstacles, it has a disadvantage in that the 60 GHz band can be used only among devices in a close space.

[0007] As a wireless LAN standard following 802.11ac and 802.11ad, the IEEE 802.11ax (High-Efficiency WLAN, HEW) standard for providing efficient and high-performance wireless LAN communication technology in a high-density environment where APs and terminals are concentrated is in the development completion stage. In a wireless LAN environment based on 802.11ax, communication with high-frequency efficiency should be provided indoors / outdoors in the presence of high-density stations and access points (APs), and various technologies for achieving such communication have been developed.

[0008] In order to support new multimedia applications, such as high-definition video and real-time gaming, new wireless LAN standards have been developed to increase the maximum transmission rate. In IEEE 802.11be (Extremely High Throughput, EHT), the 7th generation wireless LAN standard, the standard is being developed with the goal of supporting transmission rates up to 30 Gbps in the 2.4 / 5 / 6 GHz bands through wider bandwidth, increased spatial streams, multi-AP collaboration, etc. Summary of the invention

[0009] Technical issues

[0010] As described above, an object of the present invention is to provide high-speed wireless LAN services for new multimedia applications.

[0011] In addition, an object of the present invention is to provide a method and apparatus for configuring a trigger frame according to a type, the trigger frame being used to indicate transmission of a TB PPDU corresponding to a trigger frame-based PPDU.

[0012] In addition, an object of the present invention is to provide a method and apparatus for generating a high efficiency (HE) PPDU or an extremely high throughput (EHT) PPDU according to different information included in a trigger frame transmitted from an access point (AP).

[0013] The technical tasks to be achieved in this specification are not limited to the technical tasks mentioned above, and those skilled in the art can clearly understand other technical tasks not mentioned based on the following description.

[0014] Technical Solution

[0015] A terminal for sending a trigger-based physical layer protocol data unit (TB PPDU) corresponding to a response frame based on a trigger frame in a wireless communication system includes: a communication module; and a processor, which controls the communication module, wherein the processor: receives a trigger frame from an access point (AP), wherein the trigger frame includes a common information field, the common information field includes a first plurality of spatial reuse fields, and identifies whether the trigger frame includes an additional information field including a second plurality of spatial reuse fields based on identification information of the trigger frame; and sends a response frame in response to the trigger frame, the response frame being generated based on information obtained from the first plurality of spatial reuse fields or the second plurality of spatial reuse fields, and determines whether the response frame is generated based on the first plurality of spatial reuse fields or based on the second plurality of spatial reuse fields based on a format associated with the trigger frame.

[0016] Furthermore, in the present invention, when the format associated with the trigger frame is an Extremely High Throughput (EHT) format, the response frame is generated based on information obtained from the second plurality of spatial reuse fields.

[0017] Furthermore, in the present invention, when the format associated with the trigger frame is a High Efficiency (HE) format, the response frame is generated based on information obtained from the first plurality of spatial reuse fields.

[0018] Furthermore, in the present invention, whether the response frame is generated based on information acquired from the first plurality of spatial reuse fields or based on information acquired from the second plurality of spatial reuse fields is determined based on a position on a frequency axis of a resource unit where the response frame is transmitted.

[0019] Furthermore, in the present invention, the trigger frame further includes a bandwidth field, an additional bandwidth field and a resource allocation field, and the resource allocation field indicates a resource unit in which the response frame is sent.

[0020] In the present invention, the processor: identifies the resource unit in which the response frame is sent based on the resource allocation field; and generates a response frame based on information obtained from the first plurality of spatial reuse fields or the second plurality of spatial reuse fields according to the position on the frequency axis of the resource unit in which the response frame is sent.

[0021] Furthermore, in the present invention, the trigger frame further includes a puncturing mode field, which indicates whether puncturing is performed and the position of puncturing in the bandwidth indicated by the bandwidth field and / or the additional bandwidth field.

[0022] Furthermore, in the present invention, when the response frame is generated based on the second plurality of spatial reuse fields, the response frame is transmitted through a bandwidth indicated by a bandwidth field included in the common information field and an additional bandwidth field included in the additional information field.

[0023] Furthermore, in the present invention, the response frame includes a plurality of spatial reuse fields, and each of the plurality of spatial reuse fields is configured based on information obtained from each of the corresponding first plurality of spatial reuse fields or the second plurality of spatial reuse fields.

[0024] In addition, in the present invention, whether the trigger frame includes the additional information field is identified based on whether the value of a specific subfield of the common information field of the common information field and / or whether the value of an identifier of the additional information field is set to a specific value.

[0025] In addition, in the present invention, the response frame is a triggered physical layer protocol data unit (TB PPDU), the TB PPDU is aggregated with at least one TB PPDU sent from at least one other terminal to which the TB PPDU transmission is indicated by the trigger frame, and is sent in the form of an aggregate (A)-PPDU, the at least one TB PPDU is generated based on the first multiple spatial reuse fields or the second multiple spatial reuse fields, and the TB PPDU and the at least one TB PPDU are generated based on different spatial reuse fields.

[0026] In addition, the present invention provides a method, which includes: receiving a trigger frame from an access point (AP), wherein the trigger frame includes a common information field, the common information field includes a first plurality of spatial reuse fields, and identifying whether the trigger frame includes an additional information field including a second plurality of spatial reuse fields based on identification information of the trigger frame; and sending a response frame in response to the trigger frame, generating the response frame based on information obtained from the first plurality of spatial reuse fields or the second plurality of spatial reuse fields, wherein whether the response frame is generated based on the first plurality of spatial reuse fields or based on the second plurality of spatial reuse fields is determined based on a format associated with the trigger frame.

[0027] Advantageous Effects of the Invention

[0028] According to an embodiment of the present invention, by including information for generating TB PPDUs of different formats in different fields in a trigger frame and transmitting the information, transmission of TB PPDUs of multiple formats can be indicated through a single signaling.

[0029] Furthermore, according to an embodiment of the present invention, information for spatial reuse for TB PPDUs having different formats is included in different fields of a trigger frame according to each format and transmitted, which can improve the resolution of spatial reuse indicated in the TB PPDU.

[0030] Furthermore, according to an embodiment of the present invention, as the resolution of spatial reuse indicated in a TB PPDU increases, spatial reuse efficiency of an overlay basic service set (OBSS) can be improved.

[0031] In addition, according to an embodiment of the present invention, since a trigger frame is transmitted through a non-contiguous channel, TB PPDU transmission can be allowed for a plurality of STAs.

[0032] Effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned can be clearly understood from the following description by those skilled in the art to which the present invention pertains. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A wireless LAN system according to an embodiment of the present invention is illustrated.

[0034] Figure 2 A wireless LAN system according to another embodiment of the present invention is shown.

[0035] Figure 3 The configuration of a station according to an embodiment of the present invention is illustrated.

[0036] Figure 4 The diagram illustrates a configuration of an access point according to an embodiment of the present invention.

[0037] Figure 5 The process of setting up a link between a STA and an AP is schematically illustrated.

[0038] Figure 6 The diagram shows a carrier sense multiple access (CSMA) / collision avoidance (CA) method used in wireless LAN communications.

[0039] Figure 7 A PPDU format of an extremely high throughput (EHT) wireless LAN according to an embodiment of the present invention is illustrated.

[0040] Figure 8 FIG. 1 illustrates a U-SIG field of a TB PPDU according to an embodiment of the present invention.

[0041] Fig. 9 An example of a trigger format according to an embodiment of the present invention is illustrated.

[0042] Fig.10An example of a structure of a common information field (Commoninformation field) of a trigger frame according to an exemplary embodiment of the present invention is illustrated.

[0043] Fig.11 An example of a configuration of an additional information field according to a format of a trigger frame according to an embodiment of the present invention is illustrated.

[0044] Fig.12 An example of a spatial reuse field and a puncturing mode field for uplink transmission according to an embodiment of the present invention is illustrated.

[0045] Fig.13 An example of transmission of a trigger frame and a TB PPDU based on the trigger frame according to an embodiment of the present invention is illustrated.

[0046] Fig.14a and Fig.14b Another example of transmission of a trigger frame and a TB PPDU based on the trigger frame according to an embodiment of the present invention is illustrated.

[0047] Fig.15 is a flowchart illustrating an example of a method for selecting a spatial reuse field for generating a TB PPDU based on a trigger frame according to an embodiment of the present invention.

[0048] Fig.16 An example of a spatial reuse operation according to the number of spatial reuse fields for a frequency band according to an embodiment of the present invention is illustrated.

[0049] Fig.17 An example of a method of transmitting a trigger frame according to an embodiment of the present invention is illustrated.

[0050] Fig.18 An example of a TB PPDU including a puncturing mode according to an embodiment of the present invention is illustrated.

[0051] Fig.19 An example of steps of allocating resource units through a trigger frame and responding to a TB PPDU according to an embodiment of the present invention is illustrated.

[0052] Fig. 20 An example of a method of receiving a TB PPDU based on a trigger frame according to an embodiment of the present invention is illustrated.

[0053] Fig.21 Another example of a method of receiving a TB PPDU based on a trigger frame according to an embodiment of the present invention is illustrated.

[0054] Fig. 22Another example of a method of receiving a TB PPDU based on a trigger frame according to an embodiment of the present invention is illustrated.

[0055] Fig.23 Another example of a method of receiving a TB PPDU based on a trigger frame according to an embodiment of the present invention is illustrated.

[0056] Fig.24 An example of a user information field (user informationfiled) of a trigger frame according to an embodiment of the present invention is illustrated.

[0057] Fig.25 An example of a method of transmitting a TB PPDU based on a trigger frame according to an embodiment of the present invention is illustrated.

[0058] Fig.26 An example of the format of the U-SIG field of the TB PPDU according to an embodiment of the present invention is illustrated.

[0059] Fig. 27 An example of configuration and signaling of resource units for transmitting a TB PPDU according to an embodiment of the present invention is illustrated.

[0060] Fig.28 An example of signaling transmission of a puncture pattern and a segment position through a TB PPDU according to an embodiment of the present invention is illustrated.

[0061] Fig.29 The diagram illustrates an example of setting and using a subchannel for transmitting a TB PPDU according to an embodiment of the present invention.

[0062] Fig.30 An example of signal detection for a TB PPDU in response to a trigger frame according to an embodiment of the present invention is illustrated.

[0063] Fig.31 An example in which different thresholds are applied to areas predicted to be received in a signal detection process for a TB PPDU according to an embodiment of the present invention is illustrated.

[0064] Fig.32 An example of an error correction method for signal detection according to an embodiment of the present invention is illustrated.

[0065] Fig.33 is a flowchart illustrating a method in which a non-AP STA transmits a response frame to a trigger frame according to an embodiment of the present invention.

[0066] Fig.34 is a flowchart illustrating a method in which an AP STA receives a response frame to a trigger frame according to an embodiment of the present invention. DETAILED DESCRIPTION

[0067] By considering the functions of the present invention, the terms used in this specification adopt the common terms widely used at present, but the terms can be changed according to the intentions, habits and emergence of new technologies of those skilled in the art. In addition, in specific cases, there are terms arbitrarily selected by the applicant, and in this case, their meanings will be described in the corresponding description part of the present invention. Therefore, it should be understood that the terms used in this specification will not only be analyzed based on the name of the term, but also based on the essential meaning of the term and the content of the entire specification.

[0068] Throughout this specification and the claims that follow, when describing an element as being "coupled" to another element, the element may be "directly coupled" to the other element, or "electrically coupled" to the other element via a third element. In addition, unless explicitly described to the contrary, the word "comprising" will be understood to implicitly include the stated elements, but not to exclude any other elements. In addition, limitations such as "or above" or "or below" based on specific thresholds may be appropriately replaced with "greater than" or "less than", respectively. Below, in the present invention, fields and subfields may be used interchangeably.

[0069] Figure 1 A wireless LAN system according to an embodiment of the present invention is illustrated.

[0070] Figure 1 1 is a diagram illustrating a wireless LAN system according to an embodiment of the present invention. The wireless LAN system includes one or more basic service sets (BSSs), and the BSS represents a collection of devices that are successfully synchronized with each other to communicate with each other. Generally, the BSS can be divided into an infrastructure BSS and an independent BSS (IBSS), and Figure 1 The diagram shows the basic structure BSS between them.

[0071] like Figure 1 As shown, the infrastructure BSS (BSS1 and BSS2) includes one or more stations STA 1, STA 2, STA3, STA4 and STA5, access points AP-1 and AP-2 as stations providing distributed services, and a distributed system (DS) connecting multiple access points AP-1 and AP-2.

[0072] A station (STA) is a predetermined device including a media access control (MAC) and a physical layer interface for a wireless medium in accordance with the provisions of the IEEE 802.11 standard, and broadly includes both non-access point (non-AP) stations and access points (APs). In addition, in this specification, the term "terminal" may be used to refer to a non-AP STA, or an AP, or both terms. A station for wireless communication includes a processor and a communication unit, and may further include a user interface unit and a display unit according to an embodiment. The processor may generate a frame to be sent via a wireless network, or process a frame received via a wireless network, and further, perform various processes for controlling the station. In addition, the communication unit is functionally connected to the processor, and sends and receives frames via a wireless network for the station. According to the present invention, a terminal may be used as a term including a terminal (UE).

[0073] An access point (AP) is an entity that provides access to a distributed system (DS) via a wireless medium for stations associated therewith. In an infrastructure BSS, communication among non-AP stations is performed via an AP in principle, but when a direct link is configured, direct communication is even allowed among non-AP stations. Meanwhile, in the present invention, AP is used as a concept including a personal BSS coordination point (PCP), and in a broad sense may include concepts including a central controller, a base station (BS), a node B, a base transceiver system (BTS), and a site controller. In the present invention, AP may also be referred to as a base station wireless communication terminal. The base station wireless communication terminal may be used as a term that broadly includes AP, base station, eNB (i.e., eNode B), and transmission point (TP). In addition, the base station wireless communication terminal may include various types of wireless communication terminals that allocate media resources and perform scheduling for communication with multiple wireless communication terminals.

[0074] Multiple infrastructure BSSs may be connected to each other via a distribution system (DS). In this case, multiple BSSs connected via a distribution system are called an extended service set (ESS).

[0075] Figure 2 The figure shows an independent BSS according to another embodiment of the present invention, which is a wireless LAN system. Figure 2 In the embodiment, Figure 1 Same as or corresponding to Figure 1 Repetitive description of parts of the embodiments will be omitted.

[0076] Because in Figure 2 The BSS3 shown in the figure is an independent BSS and does not include an AP, and all stations STA6 and STA7 are not connected to the AP. An independent BSS is not allowed to access a distributed system and forms a self-contained network. In an independent BSS, corresponding stations STA6 and STA7 can be directly connected to each other.

[0077] Figure 3 1 is a block diagram illustrating a configuration of a station 100 according to an embodiment of the present invention. Figure 3 As illustrated in FIG. 1 , a station 100 according to an embodiment of the present invention may include a processor 110 , a communication unit 120 , a user interface unit 140 , a display unit 150 , and a memory 160 .

[0078] First, the communication unit 120 sends and receives wireless signals, such as wireless LAN packets, etc., and can be embedded in the station 100, or provided as a peripheral. According to an embodiment, the communication unit 120 may include at least one communication module using different frequency bands. For example, the communication unit 120 may include communication modules with different frequency bands (such as 2.4GHz, 5GHz, 6GHz and 60GHz). According to an embodiment, the station 100 may include a communication module using a frequency band of 7.125GHz or above, and a communication module using a frequency band of 7.125GHz or below. Each communication module may perform wireless communication with an AP or an external station according to the wireless LAN standard of the frequency band supported by the corresponding communication module. The communication unit 120 may operate only one communication module at a time, or operate multiple communication modules together at the same time, according to the performance and requirements of the station 100. When the station 100 includes multiple communication modules, each communication module may be implemented by an independent component, or multiple modules may be integrated into one chip. In an embodiment of the present invention, the communication unit 120 may represent a radio frequency (RF) communication module for processing RF signals.

[0079] Second, the user interface unit 140 includes various types of input / output devices provided in the station 100. That is, the user interface unit 140 can receive user input by using various input devices, and the processor 110 can control the station 100 based on the received user input. In addition, the user interface unit 140 can perform output based on the command of the processor 110 by using various output devices.

[0080] Next, the display unit 150 outputs an image on the display screen. The display unit 150 may output various display objects, such as content or a user interface executed by the processor 110, etc., based on the control command of the processor 110. In addition, the memory 160 stores a control program used in the station 100 and various result data. The control program may include an access program required for the station 100 to access an AP or an external station.

[0081] The processor 110 of the present invention can execute various commands or programs and process data in the station 100. In addition, the processor 110 can control various units of the station 100 and control data transmission / reception among the units. According to an embodiment of the present invention, the processor 110 can execute a program for accessing an AP stored in the memory 160 and receive a communication configuration message sent by the AP. In addition, the processor 110 can read information about the priority condition of the station 100 included in the communication configuration message, and request access to the AP based on the information about the priority condition of the station 100. The processor 110 of the present invention can represent the main control unit of the station 100, and according to an embodiment, the processor 110 can represent a control unit for individually controlling certain components of the station 100 (such as the communication unit 120, etc.). That is, the processor 110 can be a modem or a modulator / demodulator for modulating a wireless signal sent to the communication unit 120 and demodulating a wireless signal received from the communication unit 120. The processor 110 controls various operations of wireless signal transmission / reception of the station 100 according to an embodiment of the present invention. Its detailed embodiment will be described below.

[0082] exist Figure 3 The station 100 illustrated in FIG. 1 is a block diagram according to an embodiment of the present invention, where the separated blocks are illustrated as elements of a logically distinguished device. Therefore, the elements of the device can be installed in a single chip or multiple chips according to the design of the device. For example, the processor 110 and the communication unit 120 can be implemented when integrated into a single chip, or implemented as separate chips. In addition, in an embodiment of the present invention, some components of the station 100, for example, the user interface unit 140 and the display unit 150 can be selectively provided in the station 100.

[0083] Figure 4 is a block diagram illustrating the configuration of the AP 200 according to an embodiment of the present invention. Figure 4 As shown in FIG. 2 , the AP 200 according to an embodiment of the present invention may include a processor 210, a communication unit 220, and a memory 260. Figure 4 Among the components of AP200, Figure 2 The components of station 100 are the same as or correspond to Figure 2 A repeated description of parts of the components of the station 100 will be omitted.

[0084] refer to Figure 4 , the AP 200 according to the present invention includes a communication unit 220 that operates a BSS in at least one frequency band. Figure 3As described in the embodiment of the present invention, the communication unit 220 of the AP 200 may also include a plurality of communication modules using different frequency bands. That is, the AP 200 according to the embodiment of the present invention may include two or more communication modules in different frequency bands (e.g., 2.4 GHz, 5 GHz, 6 GHz, and 60 GHz) together. Preferably, the AP 200 may include a communication module using a frequency band of 7.125 GHz or above, and a communication module using a frequency band of 7.125 GHz or below. Each communication module may perform wireless communication with a station according to the wireless LAN standard of the frequency band supported by the corresponding communication module. The communication unit 220 may operate only one communication module at a time according to the performance and requirements of the AP 200, or operate a plurality of communication modules together at the same time. In an embodiment of the present invention, the communication unit 220 may represent a radio frequency (RF) communication module for processing RF signals.

[0085] Next, the memory 260 stores the control program and various result data used in the AP 200. The control program may include an access program for managing the access of the station. In addition, the processor 210 may control the various units of the AP 200 and control the data transmission / reception among the units. According to an embodiment of the present invention, the processor 210 may execute the program for accessing the station stored in the memory 260 and send a communication configuration message for one or more stations. In this case, the communication configuration message may include information about the access priority conditions of the various stations. In addition, the processor 210 performs access configuration according to the access request of the station. According to an embodiment, the processor 210 may be a modem or a modulator / demodulator for modulating a wireless signal sent to the communication unit 220 and demodulating a wireless signal received from the communication unit 220. The processor 210 controls various operations according to an embodiment of the present invention, such as the wireless signal transmission / reception of the AP 200. Its detailed embodiment will be described below.

[0086] Figure 5 is a diagram schematically illustrating a process in which a STA sets up a link with an AP.

[0087] refer to Figure 5 , in a broad sense, a link between the STA 100 and the AP 200 is set up via three steps of scanning, authentication, and association. First, the scanning step is a step in which the STA 100 obtains access information of the BSS operated by the AP 200. Methods for performing scanning include a passive scanning method in which the AP 200 obtains information by using a beacon message (S101) transmitted periodically, and an active scanning method in which the STA 100 transmits a probe request to the AP (S103), and obtains access information by receiving a probe response from the AP (S105).

[0088] The STA 100 that successfully receives the wireless access information in the scanning step performs an authentication step by sending an authentication request (S107a) and receiving an authentication response (S107b) from the AP 200. After performing the authentication step, the STA 100 performs an association step by sending an association request (S109a) and receiving an association response (S109b) from the AP 200. In this specification, association basically refers to wireless association, but the present invention is not limited thereto, and association can broadly include both wireless association and wired association.

[0089] At the same time, an authentication step (S111) based on 802.1X and an IP address acquisition step (S113) via DHCP may be additionally performed. Figure 5 In the present invention, the authentication server 300 is a server that processes 802.1X-based authentication for the STA 100, and may exist in physical association with the AP 200, or exist as a separate server.

[0090] Figure 6 is a diagram illustrating a carrier sense multiple access (CSMA) / collision avoidance (CA) method used in wireless LAN communication.

[0091] A terminal performing wireless LAN communication checks whether a channel is busy by performing carrier sensing before sending data. When a wireless signal with a predetermined strength or greater is sensed, it is determined that the corresponding channel is busy and the terminal delays access to the corresponding channel. This process is called idle channel assessment (CCA), and the level that determines whether the corresponding signal is sensed is called the CCA threshold. When a wireless signal with a CCA threshold or higher received by the terminal indicates the corresponding terminal as a recipient, the terminal processes the received wireless signal. At the same time, when no wireless signal is detected in the corresponding channel or a wireless signal with a strength less than the CCA threshold is detected, it is determined that the channel is idle.

[0092] When it is determined that the channel is idle, each terminal with data to be sent performs a backoff process after an interframe space (IFS) time, which depends on the situation of each terminal, for example, after arbitration IFS (AIFS), PCF IFS (PIFS), etc. According to this embodiment, AIFS can be used as a component to replace the existing DCF IFS (DIFS). Each terminal waits while reducing the time slot time as long as a random number determined by the corresponding terminal during the interval of the idle state of the channel, and the terminal that completely runs out of the time slot time attempts to access the corresponding channel. In this way, the interval in which each terminal performs the backoff process is called a contention window interval.

[0093] When a specific terminal successfully accesses a channel, the corresponding terminal can send data through the channel. However, when the terminal attempting to access conflicts with another terminal, the terminals that conflict with each other are assigned new random numbers respectively to perform the backoff process again. According to an embodiment, the random number newly assigned to each terminal can be determined within a range (2*CW), which is twice the range (contention window CW) of the random number previously assigned to the corresponding terminal. At the same time, each terminal attempts to access by performing the backoff process again in the next contention window interval, and in this case, each terminal performs the backoff process from the remaining time slot time in the previous contention window interval. In this way, each terminal performing wireless LAN communication can avoid mutual conflict of specific channels.

[0094] Hereinafter, in the present invention, a terminal may be referred to as a non-AP STA, an AP STA, a STA, a receiving device, or a transmitting device, but the present invention is not limited thereto.

[0095] <Examples of Various PPDU Formats>

[0096] Figure 7 A PPDU format of an extremely high throughput (EHT) wireless LAN according to an embodiment of the present invention is illustrated.

[0097] Figure 7 (a) illustrates an example of a single / multi-user transmission PPDU format, and (b) illustrates an example of a trigger-based (TB) PPDU format. Figure 7 (c) illustrates an example of a High Efficiency (HE) PPDU format of Wi-Fi 802.11ax which is a previous generation.

[0098] like Figure 7 As shown in (a) to (c), the PPDU is divided into a preamble and a data part, and the preamble can collectively include a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal field (L-SIG), and a repeated legacy signal field (RL-SIG) as a legacy field for backwards compatibility.

[0099] like Figure 7 As shown in (a) to (c) of , the legacy field may be included not only in the EHT PPDU used in 802.11be, but also in the preamble of the HE PPDU of the previous version 802.11ax.

[0100] refer to Figure 7(a) and (b), in addition to the above-mentioned legacy fields, the 11be MU / SU PPDU and 11be TB PPDU as EHT PPDU may also include a universal signal field (U-SIG), and as Figure 7 As shown in (a), the SU / MU PPDU may also include an EHT-SIG field.

[0101] U-SIG is a field newly introduced into 11be, which is an extremely high-speed communication standard, and U-SIG is a field commonly included in the next-generation 802.11 standard PPDU including 11be. The U-SIG field can continue to be included in the EHT PPDU and the subsequent generation of wireless LAN PPDU, and is used to identify which generation (including 11be) the PPDU belongs to. The U-SIG field is 2 OFDM symbols based on 64FFT and can convey a total of 52 bits of information. The interpretation of some fields of the U-SIG field can change according to the type of PPDU, whether it is multi-user transmission, or whether it is OFDMA transmission.

[0102] The EHT-SIG field is functionally composed of an EHT-VD common field, an EHT-RU (resource unit) allocation subfield, and an EHT-UE specific field, and the interpretation of some fields may be changed or some fields may be omitted depending on the type of PPDU, whether it is multi-user transmission, or whether it is OFDMA transmission.

[0103] In this case, the EHT-VD common field and the EHT-RU allocation field may be collectively referred to as the EHT-common field. The configuration and deformation (compression or omission) form of the EHT-SIG field will be described in detail in the following embodiments. The EHT-RU allocation field may be referred to as the RU allocation field.

[0104] Figure 7 The TB PPDU shown in (b) is a triggered PPDU, which means a PPDU based on a triggered frame. That is, Figure 7 The PPDU shown in (b) of FIG. 1 is a PPDU transmitted in response to a trigger frame and includes only a U-SIG field after a legacy field in the preamble, but does not include an EHT-SIG field. Figure 7 Unlike the MU / SU PPDU of (a), the U-SIG does not include information for decoding the EHT-SIG, and may include spatial reuse information, puncturing mode information for indicating whether puncturing is performed and its pattern, and the like.

[0105] Reference Figure 7 (a) to (c), the terminal may first receive and decode the preamble of the PPDU, and may receive data based on the preamble. For example, the terminal may identify whether the type of the PPDU received through the U-SIG field included in the preamble is a SU / MU PPDU, and may identify the number of content channels constituting the EHT-SIG field based on this. Thereafter, the terminal may decode the identified EHT-SIG field to identify the RU allocated through the RU allocation subfield, and receive data in the identified RU.

[0106] Figure 8 FIG. 1 illustrates a U-SIG field of a TB PPDU according to an embodiment of the present invention.

[0107] Reference Figure 8 , the TB PPDU based on the trigger frame can be divided into a preamble and data. The preamble may include a U-SIG field and an EHT-SIG field commonly included in all PPDUs, and the field configuration and inclusion or not of the EHT-SIG field vary according to the type of the PPDU. In this case, the U-SIG field may include a spatial reuse field for spatial reuse (SR) of the PPDU and a puncturing mode field for indicating whether puncturing is performed and whether puncturing is performed and its position according to each mode.

[0108] Spatial reuse refers to a method in which the STA adjusts and / or sets an appropriate CCA level according to the situation, determines whether the corresponding channel is in an idle state or an occupied state based on the adjusted and / or set CCA level, and sends a signal to effectively use spatial resources. That is, when the STA does not uniformly apply the same CCA level to all channels, and when the signal sent by the STA is determined not to have a large interference effect on other STAs when performing SR, the STA can adjust the CCA level to a lower level (or lower the determination standard for whether the channel is in an idle state), thereby more efficiently using transmission resources.

[0109] Figure 8 (a) of FIG. 1 shows an example of the configuration of the U-SIG field. Figure 8 As shown in (a), the U-SIG field can be composed of a version independent field not affected by the PHY version, a version dependent field affected by the PHY version, a CRC field (4 bits) and a Tail field (6 bits).

[0110] The version independent fields may include a PHY VER field (3 bits) for distinguishing a PHY version, a UL / DL field for indicating UL (uplink) / DL (downlink) of a corresponding PPDU, a BSS color field, a TXOP field, and a PPDU BW field.

[0111] The BSS color field indicates the BSS color index of the device that sends and receives the PPDU, and the TXOP field includes timing information related to the time point when the transmission of the PPDU ends. The PPDU BW field may include bandwidth information for sending the PPDU. When some frequency bands within the bandwidth indicated by the PPDU BW field are punctured or not allocated, the corresponding frequency bands may not be used for the transmission of the PPDU. In this case, the PPDU BW may additionally indicate information about some bandwidths that are punctured.

[0112] Since the version independent field does not change according to the type of PPDU, the version independent field can be included not only in the TB PPDU but also in the MU / SU PPDU, and can also be included in the PPDU used in the standards after 11be.

[0113] The version-related fields may include a PPDU type field (1b+a bits) and a PPDU type specific field. The PPDU type field may indicate the type of the PPDU, and the PPDU type specific field may change included subfields according to the PPDU type.

[0114] Figure 8 (b) illustrates an example of a PPDU type specific field of a TB PPDU. Specifically, the TB PPDU type specific field may include a spatial reuse field for spatial reuse and a puncturing pattern field for indicating whether to perform puncturing and / or a position.

[0115] In this case, multiple spatial reuse fields may be included according to the bandwidth. Figure 8 As shown in (b), four fields of spatial reuse fields 1 to 4 may be included in the PPDU type specific field of the TB PPDU. The value of each spatial reuse field may be encoded corresponding to each frequency region within the bandwidth indicated by the PPDU BW field of the U-SIG field.

[0116] For example, when the PPDU BW indicates 20 MHz, the spatial reuse fields 1 to 4 may all be encoded to correspond to 20 MHz indicated by the PPDU BW. Alternatively, when the bandwidth is indicated as 40 MHz by the PPDU BW field, two spatial reuse fields (e.g., 1 and 3) may be encoded to correspond to the lower 20 MHz based on the center frequency of 40 MHz, and the remaining two spatial reuse fields (e.g., 2 and 4) may be encoded to correspond to the upper 20 MHz.

[0117] Alternatively, when the bandwidth is indicated as 80 MHz by the PPDU BW field, the four spatial reuse fields may be encoded as four 20 MHz fields corresponding to 80 MHz, respectively.

[0118] When the bandwidth is indicated as 160 MHz by the PPDU BW field, the four spatial reuse fields may be encoded as four 40 MHz fields corresponding to 160 MHz, respectively.

[0119] When the bandwidth is indicated by the PPDU BW field as 260MHz, the four spatial reuse fields may be encoded as 3 20MHz of the 12 20MHz corresponding to 240MHz, respectively. In this case, the three 20MHz corresponding to the spatial reuse field 1 (SpatialReuse1) may be the three 20MHz channels with the lowest frequency components within the bandwidth of 240MHz. Alternatively, the remaining three spatial reuse fields may be encoded as corresponding to three 80MHz within 240MHz, respectively, and the remaining one spatial reuse field may be encoded as the same value as the value of the encoded three spatial reuse fields.

[0120] When the bandwidth is indicated as 320MHz by the PPDU BW field, the four spatial reuse fields may be encoded as four 80MHz corresponding to 320MHz, respectively. In this case, the 80MHz corresponding to the spatial reuse field 1 (Spatial Reuse 1) may have the lowest frequency component of 320MHz, and the 80MHz corresponding to the spatial reuse field 4 may have the highest frequency component.

[0121] The puncture mode field may indicate whether puncturing is performed and / or the position, and may be encoded as the same value as the puncture mode field of the trigger frame.

[0122] In this case, the discontinuous type of the PPDU indicated by the puncturing pattern field of the trigger frame and the combined type of the TB PPDUs sent by multiple users in the uplink (the type of the received PPDU) may be different. The reason why the discontinuous type of the PPDU indicated by the puncturing pattern is different from the combined type of the TB PPDU is that since some or all of the RUs designated by the random access RU (RA-RU) are not occupied by the STA, a discontinuous type (unutilized bandwidth type) not indicated by the puncturing pattern may be additionally generated.

[0123] The puncturing pattern field of the TB PPDU may be used to allow the AP and STA of the neighboring BSS to recognize where unused bandwidth is located among the bandwidth included in the UL BW of the TB PPDU.

[0124] Figure 8 (c) illustrates an example of a user-specific field of a TB PPDU. Figure 8 (c) According to the location (bandwidth region) of the transmitted RU or the type of the TB PPDU, the TB PPDU may include different spatial reuse fields. That is, according to the transmission location of the TB PPDU and / or the type of the TB PPDU, the spatial reuse field included in the TB PPDU may be different.

[0125] Specifically, Figure 8 As shown in (b), when the spatial reuse field of the TB PPDU for the uplink bandwidth of 320 MHz includes Spatial Reuse1, Spatial Reuse2, Spatial Reuse3, and Spatial Reuse4, each spatial reuse field corresponds to 80 MHz.

[0126] However, by setting the spatial reuse field of the TB PPDU sent in the primary and secondary differently, a total of 8 spatial reuse fields can correspond to an uplink bandwidth of 320 MHz respectively. Therefore, based on the frequency domain used to send the PPDU, each of the spatial reuse fields Spatial Reuse1 to Spatial Reuse8 included in the two types of TB PPDUs can correspond to each 40 MHHz in the UL TB PPDU BW (the bandwidth of the TB PPDU combination sent by each STA).

[0127] That is, when a non-AP STA sends a TB PPDU indicated by a trigger frame sent by an AP STA, the non-AP STA may configure and send the construction of the spatial reuse field and the puncture pattern field included in the PPDU type specific field differently according to the location of the RU sending the TB PPDU and / or the type of the TB PPDU.

[0128] For example, when the position of the RU that transmits the TB PPDU is a first type TB PPDU as the primary 160 MHz, the non-APSTA may include the spatial reuse fields Spatial Reuse1 to Spatial Reuse4 in the PPDU type specific field of the TB PPDU. However, when the position of the RU that transmits the TB PPDU is a second type TB PPDU as the secondary 160 MHz, the non-APSTA may include the spatial reuse fields Spatial Reuse5 to Spatial Reuse8 in the PPDU type specific field of the TB PPDU.

[0129] The first type and the second type may be distinguished according to the PHY version of the TB PPDU, or may be a PPDU type according to the Wi-Fi standard. For example, the first type may be an HE TB PPDU, and the second type may be an EHT-TB PPDU.

[0130] The non-AP STA may set Spatial Reuse1 to SpatialReuse8 based on information included in the trigger frame, and information for setting the spatial reuse field may be included in different fields in the trigger frame according to the location of the RU transmitting the TB PPDU and / or the type of the TB PPDU.

[0131] like Figure 8 As shown in (b), when a single spatial reuse field corresponds to 80MHz, if the spatial reuse of another BSS is limited due to some 20MHz in 80MHz, there is a question of whether the spatial reuse of the remaining reusable 60MHz should be limited together. Therefore, in order to improve the spatial reuse efficiency, the size of the bandwidth corresponding to a single spatial reuse field can be reduced, and to this end, the number of spatial reuse fields corresponding to each bandwidth can be increased.

[0132] However, in the case where multiple spatial reuse fields are set and transmitted, since the size of the U-SIG field increases, the signaling overhead increases. Figure 8 As shown in (c), when the spatial reuse field is set differently between TB PPDUs transmitted in the primary 160 MHz and the secondary 160 MHz, more spatial reuse fields can be set and transmitted without increasing signaling overhead.

[0133] According to an embodiment of the present invention, after receiving a trigger frame indicating an uplink bandwidth of 320 MHz, the transmitted TB PPDU of a single STA may be transmitted using only the RU on one side of the primary 160 MHz and the secondary 160 MHz.

[0134] According to another embodiment of the present invention, after receiving a trigger frame indicating an uplink bandwidth of 240 MHz, the transmitted TB PPDU of a single STA may be transmitted using only the RU on one side of the lower 160 MHz or the upper 160 MHz.

[0135] refer to Figure 8 (c), a TB PPDU transmitted through an RU within the primary 160 MHz may include four spatial reuse fields in the PPDU type specific field, and each of the four spatial reuse fields may correspond to four 40 MHz RUs within the primary 160 MHz, respectively.

[0136] In addition, the TB PPDU transmitted through the RU within the secondary 160 MHz may include four spatial reuse fields in the PPDU type specific field, and each of the four spatial reuse fields may correspond to four 40 MHz RUs within the secondary 160 MHz, respectively.

[0137] When the bandwidth indicated by the PPDU BW is 240MHz, the primary BW and the secondary BW may have a bandwidth of 80MHz. In this case, each of the spatial reuse fields (e.g., four spatial reuse fields) of the TB PPDU transmitted by the primary 80MHz and / or secondary 80MHz RUs may correspond to a subchannel (20MHz) within 80MHz, respectively.

[0138] In this embodiment, the PPDU type specific field includes not only the spatial reuse field, but also a puncture mode field indicating a puncture mode. Similar to the spatial reuse field, different puncture mode fields may be included depending on whether the location of the RU of the TB PPDU sent by the STA receiving the trigger frame is the primary BW or the secondary BW. That is, the puncture mode field 1 and the puncture mode field 2, which are set differently according to the bandwidth (or segment) where the RU sending the TB PPDU is located, may be included in the TB PPDU.

[0139] For example, Figure 8 As shown in (c), the puncturing pattern field 1 may be included in the TB PPDU sent in the primary 160 MHz to indicate the discontinuous channel type in the primary 160 MHz, and the puncturing pattern field 2 may be included in the TB PPDU sent in the secondary 160 MHz to indicate the discontinuous channel type of the secondary 160 MHz.

[0140] like Figure 8 As shown in (c) of FIG. 1 , when the fields indicating the puncturing mode are separately set and sent according to the bandwidth, the same as through Figure 8 Compared with the single puncturing pattern field signaling method of discontinuous channels shown in (b), high-resolution signaling can be used for the type of discontinuous channels for the entire uplink bandwidth.

[0141] <Trigger frame format>

[0142] Fig. 9 An example of a trigger format according to an embodiment of the present invention is illustrated.

[0143] Reference Fig. 9 The trigger frame may include a frame control field, a duration field, a resource allocation (RA) field, a timing advanced (TA) field, a common information field, a user information list field, a padding and an FCS field. The trigger frame may not include some of the above fields, or may also include some fields in addition.

[0144] The frame control field, the duration field, the RA field, and the TA field are the same as the fields included in a general MAC header of the 802.11 standard.

[0145] The common information field may include information on various parameters used when a device to which a resource unit is allocated through a trigger frame transmits a TB PPDU in response thereto.

[0146] The user information list may include at least one user information field including separate information for each STA. A padding field may be included to ensure time for generating and preparing a TB PPDU. When the user information field of a receiving device is located at the rear side of the user information list, the time required for the receiving device to identify the RU assigned to itself and to generate and send the TB PPDU may be insufficient. Therefore, by additionally setting a padding field after the user information list field of the trigger frame, it is possible to ensure that each receiving device has enough time to identify the RU and prepare the TB PPDU.

[0147] For a receiving device that receives a trigger frame, when the received trigger frame is a trigger frame sent to itself, a TB PPDU can be sent in response to the sent trigger frame through the RU allocated by the trigger frame as a response to the sent trigger frame. If the trigger frame is sent to multiple receiving devices, the multiple receiving devices that receive the trigger frame can send TB PPDUs at the same time, and the TB PPDUs can be combined and sent in the form of an aggregate (A)-PPDU. In addition, when PPDUs are sent from multiple STAs in response to a trigger frame and PPDUs are received in the form of A-PPDUs, the formats of the combined TB PPDUs may be different from each other. For example, HE TB PPDUs and EHT TB PPDUs can be combined, or TB PPDUs of different types (or formats) can be combined and sent.

[0148] Fig.10 An example of the configuration of a common information field (Common information field) of a trigger frame according to an embodiment of the present invention is illustrated.

[0149] The common information field may include information / parameters that are commonly applied to all terminals receiving the trigger frame. Fig.10 As shown, the trigger type field indicates the trigger type of the trigger frame and can be composed of 4 bits.

[0150] The following Table 1 illustrates an example of the type of a trigger frame according to a value of a trigger type field.

[0151]

Table 1

[0152]

[0153] Referring to Table 1, the 4 bits of the trigger type field are encoded as "0000" to "1111" to indicate the type of the trigger frame respectively. For example, the 4 bits of the trigger type field can represent basic (0), beamforming report polling (1), MU-BAR (2), MU-RTS (3), buffer status report polling (4), GCR MU-BAR (5), bandwidth query report polling (6), NDP feedback report polling (7), EHT-basic (8), EHT-beamforming report polling (9), EHT-MU-BAR (10), MU-RTS (11), EHT-buffer status report polling (12), EHT-GCR MU-BAR (13), EHT-bandwidth query report polling (14) and EHT-NDP feedback report polling (15) type trigger frames according to the encoded value.

[0154] According to the bit value "0" to "7" of the trigger type field, the same trigger frame type as the trigger type field of HE (802.11ax) can be indicated. Therefore, when the value of the trigger frame type field of the HE trigger frame (the trigger frame is based on HE) is "0" to "7", the trigger frame can be configured to be the same as 802.11ax, so that the common information field, the trigger-related common information field, and the user field can be configured and encoded to have the same format.

[0155] However, only when the PHY version of the trigger frame is EHT (11be), the type of the trigger frame with the bit value of the trigger type field being "8" to "15" can be indicated. That is, only when the trigger frame is an EHT-based EHT trigger frame, the bit value of the trigger type field can be set to a value from "8" to "15". The EHT-based EHT trigger frame with the value of the trigger type field being "8" to "15" can perform the same functions as the corresponding trigger frames of "0" to "7", respectively.

[0156] When the value of the trigger type field is "8" to "15", since it is an EHT-based EHT trigger frame, a field different from the HE-based HE trigger field whose trigger type field value is "0" to "7" (e.g., an additional information field) may be included. For example, the trigger frame whose trigger type value is "8" to "15" may further include an additional bandwidth field, a puncturing pattern field, and / or an additional UL spatial reuse field for additional spatial reuse, etc. Such additional information fields may be used to apply functions newly added to EHT (e.g., 240 / 320 MHz operation, multiple RU allocation, etc.) to operations based on the trigger frame.

[0157] The additional information field may be added by extending a field that is functionally identical to a field included in a trigger frame having a trigger type field value of "0" to "7" or by using a reserved field.

[0158] like Fig.10 As shown, the size of the UL BW field may vary according to the value of the trigger type field. For example, when the value of the trigger type field is '0' to '7', the size of the UL BW field is 2 bits. However, if the value of the trigger type field is '8' to '15', the size of the UL BW field may be 3 bits and may indicate 6 BW modes (20, 40, 80, 160 (80+80), 240 (160+80), 320 (160+160) MHz).

[0159] The size of the UL spatial reuse field may vary according to the value of the trigger type field. For example, when the value of the trigger type field is "0" to "7", the size of the UL spatial reuse field is 16 bits. However, if the value of the trigger type field is "8" to "15", the number of UL spatial reuse fields may be a total of 32 bits, which is composed of 8 spatial reuse fields of 4 bits in size.

[0160] The reason why it is composed of a total of 8 spatial reuse fields is that when only 4 spatial reuse fields are used for 240MHz or 320MHz PPDU as in the prior art, the BW corresponding to each spatial reuse field reaches a maximum of 80MHz, making it impossible to effectively perform spatial reuse. Therefore, when the number of spatial reuse fields is increased to 8, the maximum corresponding to only 40MHz, so the spatial reuse operation can be performed more effectively.

[0161] When the trigger type is 8 to 15, the UL HE-SIG-A2 reserved field may be used as a puncturing pattern field.

[0162] Fig.11 An example of a configuration of an additional information field according to a format of a trigger frame according to an embodiment of the present invention is illustrated.

[0163] Reference Fig.11 Depending on whether the trigger frame is based on HE or EHT, the trigger frame may include an additional information field. The additional information field may also include additional information for responding to a TB PPDU based on the EHT trigger frame.

[0164] Specifically, when the value of the trigger type field included in the trigger frame is set to a value of "8" to "15" so that the trigger frame is an EHT trigger frame, the trigger frame may also include Fig.11 An additional Trigger Dependent Common Info subfield is shown as an additional information field.

[0165] As described above, the additional information field may include an additional bandwidth field, a puncturing pattern field, and / or an additional UL spatial reuse field for additional spatial reuse, etc. At this time, the common information field except the additional information field may have the same bit and field configuration in a trigger frame having a value of the trigger type field of "0" to "7" and a trigger frame having a value of the trigger type field of "8" to "15".

[0166] Fig.11The additional information field shown may be commonly included in an EHT-based trigger frame in which the value of the trigger type field is "8" to "15", and when the value of the trigger type field is "13" (EHT-GCR MU-BAR), it may be included therein together with BAR control (2 octets) and BAR information (2 octets).

[0167] When a PPDU is transmitted in response to an EHT-based trigger frame, the additional information field includes additional information for generating an EHT TB PPDU. The additional information field may be immediately after the common information field and may have a size of 1 or 2 bits.

[0168] In addition, a specific field immediately before the additional information field may indicate whether the additional information field is included after the common information field. That is, when the value of the specific field is set to a specific value ("1" or "0"), the non-AP STA may recognize that the additional information field is included after the common information field. In this case, the trigger frame may be recognized as an EHT trigger frame, and the non-AP STA may respond with an EHT TB PPDU. If the specific field indicates that the additional information field is not included, the trigger frame may be recognized as an HE trigger frame, and the non-AP STA may respond with an HE TB PPDU. In this case, the specific field may have a size of 1 bit and may be "B63", "B53", or other bits.

[0169] The non-AP STA may know whether the additional information field is included after the common information field through the identifier of the additional information field other than the specific field. For example, if the value of the identifier of the additional information field (e.g., association identifier (AID)) is set to a specific value (e.g., AID=2007), it may indicate that the additional information field is included after the common information field.

[0170] When the received trigger frame is an HE trigger frame, the non-AP STA may respond with an HE TB PPDU, and may respond with an HE TB PPDU or an EHT TB PPDU based on the received trigger frame. In this case, if the position of the RU allocated for transmission of the response frame to the trigger frame is located in a bandwidth without a primary channel, the non-AP STA may only transmit an EHT TB PPDU as a response to the trigger frame. That is, if the position of the allocated RU is located in the primary BW, the non-AP STA may respond with an HE TB PPDU or an EHT TB PPDU according to the configuration and type of the trigger frame, but if the position of the allocated RU is located in the secondary BW, the non-AP STA may only respond with an EHT TB PPDU.

[0171] For example, the non-AP STA may respond with a TB PPDU or an EHT TB PPDU based on a format related to a trigger frame (e.g., a case where the format of the user information field included in the trigger frame is the HE format or the EHT format). Specifically, after receiving the trigger frame, if the format of the user information field included in the trigger frame is the HE format, the non-AP STA responds with a HETB PPDU. However, if the format of the user information field included in the trigger frame is the EHT format, the non-AP STA may respond with an EHT TB PPDU.

[0172] The additional information field may be referred to as a special user information field, and fields included in the additional information field may be interpreted together with fields included in the common information.

[0173] The additional UL bandwidth field may be allocated 1 bit or 2 bits and may be combined with the bandwidth field included in the common information field for interpretation. That is, when the additional information field includes the additional UL bandwidth field, the non-AP STA may identify the bandwidth used to transmit the TB PPDU by additionally considering the additional UL bandwidth field on the basis of the bandwidth field of the common information field. In this case, 6 of the 8 (or 16) BW modes that can be indicated by 2 bits of the bandwidth field and 1 bit (or 2 bits) of the UL BW field may correspond to 20, 40, 80, 160 (80+80), 240 (160+80), and 320 (160+160) MHz, respectively.

[0174] The additional UL spatial reuse field may signal a value for a spatial reuse operation in a frequency domain that is not indicated by the UL spatial reuse field of the common field. The UL spatial reuse field of the common information field may include 4 spatial reuse fields, and the additional UL spatial reuse field may include 4 spatial reuse fields, thereby indicating a total of 8 spatial reuse fields for the entire bandwidth. That is, the multiple spatial reuse fields included in the common information field and the additional UL spatial reuse field included in the additional information field may respectively indicate frequency bands for spatial reuse operations of different bandwidths.

[0175] For example, when the spatial reuse fields included in the common information field indicate the frequency bands for the spatial reuse operation of the primary BW, respectively, the additional spatial reuse fields included in the additional information field may indicate the frequency bands for the spatial reuse operation of the secondary BW. Therefore, when a TB PPDU is transmitted in the primary BW (alternatively, when the TB PPDU is an HE TB PPDU), the non-AP STA may generate the TB PPDU using the spatial reuse field included in the common information of the trigger frame. However, when a TB PPDU is transmitted in the secondary BW (alternatively, when the TB PPDU is an EHT TB PPDU), the non-AP STA may generate the TB PPDU by using at least one spatial reuse field included in the additional information field of the trigger frame.

[0176] That is, when transmitting a TB PPDU in response to a trigger frame, the non-AP STA may generate a TB PPDU using at least one spatial reuse field included in different fields according to whether the TB PPDU to be responded to is a HE TB PPDU or an EHT TB PPDU.

[0177] The puncture pattern field can signal the discontinuous type of the PPDU that transmits the trigger frame. The trigger frame can be transmitted using discontinuous channels other than some channels in the working BW, and the discontinuous channel type of the RU that transmits the trigger frame can be indicated by the puncture pattern field.

[0178] In addition, the puncture pattern field of the trigger frame can be encoded by applying the same pattern as the puncture pattern field of the SU PPDU. In addition, in order to signal the discontinuous channel type of the entire PPDU BW instead of the puncture pattern field, a bitmap (8-bit or 16-bit bitmap) indicating whether each 20MHz channel is used can be included.

[0179] Fig.12 An example of a spatial reuse field and a puncturing mode field for uplink transmission according to an embodiment of the present invention is illustrated.

[0180] Fig.12 (a) illustrates an embodiment of a UL spatial reuse field for UL spatial reuse operation, which consists of a total of 8 spatial reuse fields. Among the 8 spatial reuse fields appearing in a trigger frame for 320 (or 160+160) MHz bandwidth, 4 may indicate values ​​for spatial reuse corresponding to low 160 or 80 MHz, and the remaining 4 may indicate values ​​for spatial reuse corresponding to high 160 or 80 MHz.

[0181] in this case, Fig.12 The multiple spatial reuse fields shown in (a) may be separately included in the UL spatial reuse field included in the common field and the additional UL spatial reuse field included in the additional information field. That is, some of the multiple spatial reuse fields may be included in the UL spatial reuse field included in the common field, and the remaining spatial reuse fields may be included in the additional UL spatial reuse field included in the additional information field.

[0182] Each spatial reuse field consists of 4 bits and may indicate a spatial reuse value applied to a maximum 40 MHz bandwidth.

[0183] For example, when the total bandwidth is 320MHz, the four spatial reuse fields corresponding to the main 160MHz may correspond to the lower 40MHz of the lower 80MHz, the upper 40MHz of the lower 80MHz, the lower 40MHz of the upper 80MHz, and the upper 40MHz of the upper 80MHz, respectively. Similarly, the four spatial reuse fields corresponding to the upper 160MHz may correspond to the lowest 40MHz, the lower 40MHz, the upper 40MHz, and the highest 40MHz of the upper 160MHz, respectively.

[0184] When the total bandwidth is 240 (or 160 + 80 or 80 + 160) MHz, four of the eight spatial reuse fields included in the trigger frame may correspond to low 160 MHz or low 80 MHz, and the remaining four spatial reuse fields may correspond to high 80 MHz or high 160 MHz. In this case, the terms "low" and "high" are only used to divide the frequency domain into 160 MHz + 80 MHz, and may have nothing to do with the positional relationship of the actual frequency. In this case, the four spatial reuse fields corresponding to 80 MHz may be set to indicate a spatial reuse value of 20 MHz, respectively.

[0185] When the total bandwidth is 160 (or 80+80) MHz, four of the eight spatial reuse fields included in the trigger frame may correspond to 40 MHz (lowest 40 MHz, low 40 MHz, high 40 MHz, highest 40 MHz), respectively, and the remaining four spatial reuse fields may be encoded as the same values ​​as the spatial reuse fields corresponding to the respective 40 MHz.

[0186] In addition, when the trigger frame indicates a bandwidth of 80 MHz, four of the eight spatial reuse fields may correspond to 20 MHz (lowest 20 MHz, low 20 MHz, upper 20 MHz, highest 20 MHz), respectively, and the remaining four spatial reuse fields may be encoded as the same values ​​as the spatial reuse fields corresponding to the respective 20 MHz.

[0187] In addition, when the trigger frame indicates a bandwidth of 40 MHz, four of the eight spatial reuse fields may correspond to 20 MHz (low 20 MHz, upper 20 MHz), respectively, and the remaining six spatial reuse fields may be encoded as the same values ​​as the spatial reuse fields corresponding to the respective 20 MHz.

[0188] Furthermore, when the trigger frame indicates a bandwidth of 20 MHz, all eight spatial reuse fields may indicate spatial reuse values ​​corresponding to the primary 20 MHz.

[0189] In another embodiment of the present invention, the UL spatial reuse field may include four spatial reuse fields. In this case, each of the four spatial reuse fields may indicate a spatial reuse value of 80 MHz for a 320 MHz bandwidth, and may indicate a value of 40 MHz spatial reuse for a 160 MHz bandwidth. In addition, for a bandwidth of 80 MHz, a value of 20 MHz spatial reuse may be indicated.

[0190] When the trigger frame indicates a bandwidth of 40MHz, two spatial reuse fields may correspond to low or high 20MHz, respectively, and the remaining two spatial reuse fields may be encoded as the same value as the spatial reuse field corresponding to each 20MHz. In addition, when the trigger frame indicates a bandwidth of 20MHz, all four spatial reuse fields may indicate a spatial reuse value corresponding to the main 20MHz.

[0191] Fig.12 (b) illustrates an example of a puncture pattern field (8 bits or 16 bits). The puncture pattern field indicates the type of discontinuous channel used to send the PPDU of the trigger frame. That is, the puncture pattern of the bandwidth used to send the trigger frame PPDU can be indicated by the puncture pattern field. In this case, the puncture pattern can indicate whether some bandwidth in the entire bandwidth is punctured and the position of the puncture.

[0192] The puncturing mode field (or 16-bit bitmap) may be included in the additional information field instead of the (UL HE-SIG-A2) reserved field of the common information field, and may include two puncturing mode subfields. If two puncturing mode subfields are included, the puncturing mode subfield may indicate whether to be punctured and the punctured position by dividing the discontinuous type of the channel used to transmit the trigger frame included in the PPDU of 320 MHz or 240 MHz into a bandwidth segment of 160 MHz.

[0193] Fig.13 An example of transmission of a trigger frame and a TB PPDU based on the trigger frame according to an embodiment of the present invention is illustrated.

[0194] Reference Fig.13 When a trigger frame is sent in a form including multiple spatial reuse fields, each STA can send a response frame as a response to the trigger frame based on the multiple spatial reuse fields.

[0195] Specifically, STA 1 to STA N that receive the trigger frame from the AP STA can check the UL spatial reuse field included in the common information field of the trigger frame, and generate a TB PPDU by respectively encoding the values ​​of the four spatial reuse fields included in the UL spatial reuse field into spatial reuse fields 1 to 4 included in the U-SIG field of the TB PPDU.

[0196] Fig.14a and Fig.14b is another example illustrating transmission of a trigger frame and a TB PPDU based on the trigger frame according to an embodiment of the present invention.

[0197] Reference Fig.14a and 14b , when multiple spatial reuse fields are indicated by a trigger frame, TB PPDU can be generated and transmitted through different spatial reuse fields.

[0198] Specifically, a plurality of spatial reuse fields may be transmitted through a trigger frame. In this case, some of the plurality of spatial reuse fields may be included in the common information field, and the remaining spatial reuse fields may be included in the additional information field.

[0199] In this case, the non-AP STA can generate a response frame by using the spatial reuse field included in the common information field or the additional information field according to the position of the RU allocated to itself or whether the response frame to the trigger frame is a HE TB PPDU or an EHT TB PPDU.

[0200] For example, when the position of the RU allocated to the non-AP STA is included in the secondary BW, or the format associated with the trigger frame is the EHT format (for example, when the format of the user information field is the EHT format), the non-AP STA can generate an EHT TB PPDU using the spatial reuse field included in the additional information field, and transmit the generated EHT TB PPDU as a response frame of the trigger frame. However, when the position of the RU allocated to the non-AP STA is included in the primary BW, or the format associated with the trigger frame is the HE format (for example, when the format of the user information field is the HE format), the non-AP STA can generate an HE TB PPDU using the spatial reuse field included in the common information field, and transmit the generated HE TB PPDU as a response frame of the trigger frame.

[0201] For example, Fig.14a As shown, among the non-AP STAs 1 to STA N that have received the trigger frame, STAs 1 to STAn whose positions of RUs allocated by the trigger frame are located at lower 160 MHz or lower 80 MHz based on the center frequency select spatial reuse fields 1 to 4 corresponding to lower 180 MHz or lower 80 MHz from 8 spatial reuse fields 1 to 8 included in the trigger frame. STAs 1 to STA n may encode each of the selected spatial reuse fields 1 to 4 into each of the spatial reuse fields 1 to 4 included in the U-SIG field of the TBPPDU which is a response frame to the trigger frame.

[0202] In this case, when the TB PPDU generated by STA 1 to STAn is a HE TB PPDU, the spatial reuse fields 1 to 4 may be spatial reuse fields included in the common information field of the trigger frame, and when the TB PPDU generated by STA 1 to STAn is an EHT TB PPDU, the spatial reuse fields 1 to 4 may be spatial reuse fields included in the additional information field of the trigger frame.

[0203] like Fig.14b As shown, among the non-AP STAs (i.e., STA 1 to STA N) that have received the trigger frame, the positions of the RUs allocated by the trigger frame are located at high 160 MHz or high 80 MHz based on the center frequency, and STA An+1 to STA N select spatial reuse fields 5 to 8 corresponding to high 180 MHz or high 80 MHz from 8 spatial reuse fields 1 to 8 included in the trigger frame. STA An+1 to STA N may encode the selected spatial reuse fields 5 to 8 into spatial reuse fields 1 to 4 included in the U-SIG field of the TB PPDU which is a response frame to the trigger frame.

[0204] In this case, when the TB PPDU generated by STA n+1 to STA N is an HE TB PPDU, spatial reuse fields 5 to 8 may be spatial reuse fields included in the common information field, and when the TB PPDU generated by STA 1 to STA n is an EHT TB PPDU, spatial reuse fields 5 to 8 may be spatial reuse fields included in the additional information field.

[0205] exist Fig.14a and 14b In the trigger frame, the trigger frame may indicate the transmission of the HE TB PPDU and / or the EHT TB PPDU. In this case, at least one non-AP STA that receives the trigger frame may send the HE TB PPDU or the EHT TB PPDU in response to the trigger frame. The criteria for at least one non-AP STA to send the TB PPDU or the EHT TB PPDU may be based on the position of the allocated RU and / or the format associated with the trigger frame.

[0206] For example, when the position of the RU allocated by the trigger frame is a secondary BW that does not include the primary channel, or the format associated with the trigger frame is an EHT format (for example, when the format of the user information field is an EHT format), an EHT TB PPDU may be generated in response to the trigger frame and the EHT TB PPDU may be transmitted. However, when the position of the RU allocated by the trigger frame is a primary BW that includes the primary channel or the format associated with the trigger frame is an HE format (for example, when the format of the user information field is an HE format), an HE TB PPDU may be generated in response to the trigger frame and the HE TB PPDU may be transmitted.

[0207] Fig.15 is a flowchart illustrating an example of a method for selecting a spatial reuse field for generating a TB PPDU based on a trigger frame according to an embodiment of the present invention.

[0208] Reference Fig.15 , the STA that receives the trigger frame can identify the RU used for uplink transmission by decoding the preamble of the trigger frame, and can generate a TB PPDU by using the spatial reuse field of different trigger frames according to the position of the identified RU.

[0209] Specifically, the AP STA may transmit a trigger frame indicating transmission of the TB PPDU, and the non-AP STA may receive the trigger frame from the AP STA and decode the received trigger frame (S15010).

[0210] Then, the non-AP STA may generate a TB PPDU to transmit the TB PPDU indicated by the trigger frame in response to the received trigger frame. In this case, the non-AP STA may generate a TB PPDU using information included in the trigger frame.

[0211] Specifically, the non-AP STA can decode the trigger frame and identify the RU allocated to send its own TB PPDU through the RU allocation information field of the trigger frame. The non-AP STA determines whether the position of the RU allocated for transmission of the TB PPDU is a high frequency band (or a primary BW including a primary channel) or a low frequency band (or a secondary BW not including a primary channel) based on the center frequency of the total bandwidth. If the position of the allocated RU is located in the high frequency band (or the primary BW), the non-AP STA can generate a TB PPDU by encoding the spatial reuse fields 1 to 4 included in the trigger frame into the spatial reuse fields 1 to 4 of the TB PPDU (S15020).

[0212] In this case, when the generated TB PPDU is an HE TB PPDU, spatial reuse fields 1 to 4 of a trigger frame for generating the TB PPDU may be spatial reuse fields included in a common information field of the trigger frame.

[0213] However, when the position of the allocated RU is located in the low frequency band (or secondary BW), the non-AP STA may generate a TB PPDU by encoding spatial reuse fields 5 to 8 included in the trigger frame into spatial reuse fields 1 to 4 of the TB PPDU (S15030).

[0214] In this case, when the generated TB PPDU is an EHT TB PPDU, spatial reuse fields 5 to 8 of a trigger frame for generating the TB PPDU may be spatial reuse fields included in an additional information field of the trigger frame.

[0215] Fig.16 An example of a spatial reuse operation according to the number of spatial reuse fields for a frequency band according to an embodiment of the present invention is illustrated.

[0216] refer to Fig.16 , an area of ​​a bandwidth corresponding to a spatial reuse field and a spatial reuse result of an OBSS may vary according to the number of spatial reuse fields of a bandwidth used for transmission of a PPDU.

[0217] Specifically, Fig.16 As shown, there are four OBSS1 to 4 having primary channels in a 320 MHz bandwidth transmitting a 320 MHz TB PPDU, and each of the four OBSS1 to 4 may receive interference of -65, -60, -58, and -50 dBm from the TB PPDU.

[0218] In this case, when only four spatial reuse fields are used, such as Fig.16 As shown in (a) of FIG. 1 , the four spatial reuse fields can be set to values ​​related to the spatial reuse restrictions allowed in 80 MHz. On the other hand, when eight spatial reuse fields are used, as shown in FIG. Fig.16 As shown in (b), eight spatial reuse fields can be set to values ​​related to the spatial reuse restrictions allowed in 40MHz. In this case, the value set in the spatial reuse field can be set to the most stringent value in the spatial reuse condition applied in the BW corresponding to the spatial reuse field. Therefore, a spatial reuse field corresponding to 80MHz can be set to the lower value (more limited spatial reuse) of the two spatial reuse field values ​​corresponding to the two 40MHz in 80MHz.

[0219] For example, four spatial reuse values ​​are used for a bandwidth of 320 MHz through a TB PPDU. Fig.16 As shown in (a), in OBSS1 to OBSS 4, the spatial reuse value of the bandwidth where the main channel of each STA is located can be PSR_DISALLOW, -68dBm, -68dBm, PSR_DISALLOW. In this case, the STA confirms that the spatial reuse operation is not allowed and does not attempt channel access. In addition, although OBSS2 and OBSS 3 can know that spatial reuse is allowed in the bandwidth where their own main channels are located, since the interference of OBSS2 and OBSS 3 is greater than the spatial reuse threshold, OBSS2 and OBSS 3 cannot perform the backoff process for channel access.

[0220] On the other hand, if eight spatial reuse values ​​are used for a bandwidth of 320 MHz through a TB PPDU, Fig.16 As shown in (b), in OBSS1 to OBSS 4, the spatial reuse value of the bandwidth where the main channel of each STA is located can be -72dBm, -38dBm, -41dBm, PSR_DISALLOW. In this case, since spatial reuse of OBSS2 and OBSS 3 is allowed in the bandwidth where their own main channels are located, and the interference of OBSS2 and OBSS 3 (from TB PPDU) is less than the spatial reuse threshold, OBSS2 and OBSS 3 can perform transmission after performing the backoff process for channel access.

[0221] Fig.17 An example of a method of sending a trigger frame according to an embodiment of the present invention is illustrated.

[0222] Reference Fig.17(a) to (c) may change the type of the sending trigger frame according to the type and quantity of resources to be sent.

[0223] Specifically, since the trigger frame of 11be is a MAC frame, the trigger frame can be sent at 20, 40, 80, 160 and 320 MHz according to the BW of the PPDU that sends the trigger frame.

[0224] like Fig.17 As shown in (a), when some of the working BW of the AP is occupied by a heterogeneous device or OBSS (the result of CCA is BUSY), the BW of the PPDU for sending the trigger frame is limited so that the trigger frame can be sent only through some of the working BW. This is a problem that occurs when the wide bandwidth channel access method follows the channel bonding method, and the trigger frame can be sent to a wider BW using a channel other than the channel determined to be BUSY by introducing a puncturing operation of the SU PPDU of 11be.

[0225] like Fig.17 As shown in (b), the trigger frame can be sent only through the frequency band within the working BW except the channel whose CCA result is determined to be BUSY. In this case, the discontinuous type of the PPDU that sends the trigger frame can be signaled by the EHT PHY that appears before the MAC frame including the trigger frame. In this case, the discontinuous type of the PPDU that sends the trigger frame can be limited depending on the discontinuous type of the SU PPDU allowed in the EHT. In addition, the trigger frame can be sent in a discontinuous type that appears repeatedly in every 20MHz PPDU and does not appear only in a specific channel (a channel where the CCA result is BUSY). In this case, the transmission type of the trigger frame can be a method similar to the U-SIG transmission method that appears in the perforated PPDU.

[0226] like Fig.17 As shown in (c), two trigger frames can be sent at the same time. This is because the working BW of the STA that sends the TB PPDU through the trigger frame can be included only in some of the BWs of the trigger frame sent by the AP. For example, the working BW of the STA that sends the UL MU TB PPDU through the 320MHz trigger frame can be limited to only exist within the lower 160MHz or the upper 160MHz.

[0227] In this case, two trigger frames can be sent by dividing the PPDU BW into two regions. The criterion for dividing the BW of the PPDU into two regions can be whether the BW of one region is 160MHz. That is, the BW of the PPDU can be divided so that the BW of one PPDU is 160MHz.

[0228] In addition, each of the trigger frames appearing in the two regions may appear in each region in a discontinuous type. At this time, the discontinuous types respectively appearing in the two trigger frames may be limited depending on the discontinuous type of the SU PPDU allowed in the BW including the two trigger frames. Fig.17 In (c), the discontinuous channel types allowed in trigger 1 may be limited to only the discontinuous channel types allowed in a 160 MHz SU PPDU.

[0229] Fig.18 An example of a TB PPDU including a puncturing mode according to an embodiment of the present invention is illustrated.

[0230] In the case where the puncturing pattern is transmitted through trigger frame signaling, when the STA configures its own TB PPDU, the STA may include information about the puncturing pattern obtained through the trigger frame in its own TB PPDU. Fig.18 As shown in (a), when the puncturing mode field is included in the signaling field of the TB PPDU, the OBSS receiving the corresponding TB PPDU can identify the discontinuous type of channels occupied by all TB PPDUs sent together with the TB PPDU even if only the 20 MHz TB PPDU signaling information obtained through its main channel is used.

[0231] In addition, information about the puncturing pattern can be used to more finely divide the frequency domain corresponding to the spatial reuse value. For example, if it is obtained through the puncturing pattern information whether some of the BW areas corresponding to the spatial reuse field are punctured, the BW area corresponding to the spatial reuse field can correspond only to the remaining area except for the bandwidth punctured by the puncturing pattern information.

[0232] like Fig.18 As shown in (b), when information about some BWs being punctured is confirmed through the puncturing pattern information of the puncturing pattern field, information of the spatial reuse field corresponding to each BW can be applied only to the remaining BWs that are not punctured in the corresponding BW.

[0233] <Dynamic RU TB PPDU>

[0234] Trigger frames and UL MU (UL MU-MIMO or UL OFDMA) transmission using TB PPDU can reduce contention between STAs by allowing multiple STAs to perform UL transmission simultaneously, while effectively solving the problem of excessive overhead that may be caused by short PPDU (UL) transmission of a single STA. However, unlike general UL PPDU transmission, there is a limitation in that each STA must use the RU allocated from the AP via the trigger frame to perform UL transmission, regardless of its own channel state (IDLE or BUSY).

[0235] The above-mentioned problem of limited RU selection on the STA side may be caused by the difference between the TB PPDU receiving process on the AP side and the general receiving process. Fig.19 and Fig. 20 An embodiment of a process in which an STA that has received a trigger frame performs a response using a TB PPDU and an operation in which an AP receives a TB PPDU transmitted by each STA in UL is illustrated.

[0236] Fig.19 An example of allocating resource units through a trigger frame and responding to a TB PPDU according to an embodiment of the present invention is illustrated.

[0237] Reference Fig.19 In the embodiment, the AP can allocate RUs of the lower 40MHz band and the upper 40MHz band (484-tone size RUs, respectively) to STA1 and STA2, respectively, by sending a trigger frame using the 80MHz band confirmed as IDLE. In this case, since the trigger frame allocates RUs located at different frequencies to the two STAs, the trigger frame can be understood as a trigger frame for UL OFDMATB PPDU.

[0238] After receiving the trigger frame, STA1 and STA2 decode the received trigger frame and confirm that the trigger frame includes two user information fields (User Info field), and one of the two user information fields is its own user information field. In this case, each STA can identify its own user information field based on whether the AID12 subfield of the user information field includes information related to its own AID (e.g., its own AID LSB 12 bits).

[0239] STA1 can confirm that the RU allocated to itself is a 484-tone RU located in the lower 40 MHz through the RU allocation subfield included in its own user information field, and STA2 can confirm that the RU allocated to itself is a 484-tone RU located in the upper 40 MHz in the same manner as STA1.

[0240] In addition, in addition to information about the RU (and SS (spatial stream)) allocated to each STA, the trigger frame may also include various coding parameters and PPDU length information that need to be applied when each STA generates a TB PPDU in response to the trigger frame. Each STA decodes and confirms the RU allocated to itself, and then generates a TB PPDU by applying the coding parameters indicated by the trigger frame. The generated TB PPDU of each STA can be sent simultaneously in UL, and the AP can receive the UL OFDMA PPDU combined with the TB PPDU sent by each STA.

[0241] When considering the transmission of the trigger frame and its corresponding UL OFDMA PPDU reception process briefly described above, the received OFDMA TB PPDU should be divided into TB PPDUs for each STA so that the AP obtains the TB PPDU sent by each STA in UL. However, the MAC of the AP, which is the subject of generating the trigger frame, knows the location and type of the RU allocated to each STA, while the PHY of the AP, which is the subject of dividing and decoding the OFDMA TB PPDU, does not know the configuration of the OFDMA TB PPDU it will receive. Therefore, in the existing 11ax standard, the following process is defined, namely: the MAC sublayer of the AP generates a trigger frame, requests the PHY layer to perform the transmission, and then provides the PHY layer with the information required to receive the expected TB PPDU as a response to the above-mentioned trigger frame.

[0242] In 11ax, after MAC performs a request for sending a trigger frame, in response to a trigger frame requesting to send a TB PPDU, a PHY-TRIGGER.request primitive is issued before receiving a TB PPDU from a STA. In this case, PHY-TRIGGER.request is issued to request the PHY entity to set parameters for receiving a TB PPDU.

[0243] The PHY-TRIGGER.request primitive provides a TRIGVECTOR parameter, and the TRIGVECTOR parameter includes the BW information (CH_BANDWIDTH) and L-SIG length information (UL_LENGTH) of the predicted TB PPDU. In this case, the PHY uses the BW information and length information of the TB PPDU received from the MAC to set the BW of the Rx mode, thereby performing preparations for the reception of the TB PPDU.

[0244] In addition, the TRIGVECTOR parameters include AID12_LIST and RU_ALLOCATION_LIST of STAs to which RUs are allocated through trigger frames. AID12_LIST and RU_ALLOCATION_LIST are used by PHY to distinguish the subcarriers where each STA's TB PPDU exists in the TBPPDU (OFDMA UL PPDU) received from multiple STAs. As a result, PHY can separate each user's TB PPDU from the TB PPDU.

[0245] TRIGVECTOR may include coding-related parameters commonly applied to the TB PPDU, MCS information used in the TB PPDU of each STA, and the like, and the PHY may decode the TB PPDU of each STA by using the coding-related information.

[0246] As described above, if it is considered that MAC uses TRIGVECTOR to provide PHY with information related to the predicted received TB PPDU, the reception process of the TB PPDU may be different from the reception process of the general PPDU. In other words, unlike the case of receiving a general PPDU, the PHY does not obtain information for decoding the TB PPDU being received from the preamble and SIG fields of the TB PPDU being received, but can wait for the reception of the TB PPDU and decode it based on the information provided by the MAC.

[0247] Fig. 20 An example of a method of receiving a TB PPDU based on a trigger frame according to an embodiment of the present invention is illustrated.

[0248] Reference Fig. 20 , the PHY of the AP may receive the TRIGVECTOR from the MAC sublayer and may receive the predicted TB PPDU based on the information included in the TRIGVECTOR.

[0249] Specifically, Fig. 20 As shown, the MAC sublayer issues a PHY-TRIGGER.request primitive to the local PHY entity. At this time, the TRIGGER.request primitive may be issued after the MAC requests the PHY to send a trigger frame and before the TB PPDU is received in response to the trigger frame.

[0250] The PHY that receives the TRIGGER.request primitive from the MAC can recognize that the BW of the TB PPDU predicted to be received is 80MHz through the CH_BANDWIDTH parameter in the TRIGVECTOR parameter. After that, the PHY performs reception of the 80MHz TB PPDU and divides the TB PPDU received through OFDMA into TB PPDUs for each user using the AID12_LIST and RU_ALLOCATION_LIST in the TRIGVECTOR parameter received from the MAC.

[0251] The process of dividing the TB PPDU into TB PPDUs for each STA may be performed using the AID12_LIST parameter and the RU_ALLOCATION_LIST parameter in the TRIGVECTOR parameter. Fig. 20 As shown, the AID12_LIST parameter may include the AID LSB 12 bits of STA 1 and STA 2 as entries. Thus, the PHY may recognize that the TB PPDU being received is a combination of the TB PPDU of STA 1 and the TB PPDU of STA 2. In addition, the PHY may confirm information about the types presented by the TB PPDUs of STA 1 and STA 2 through RU_ALLOCATION_LIST, thereby determining that the RU of the STA is a 484-tone RU located in the lower 40 MHz band, and the RU of STA 2 is a 484-tone RU located in the upper 40 MHz band. Therefore, the PHY may determine the positions of the RUs transmitted by TB PPDU1 and TB PPDU2 transmitted by STA 1 and STA 2, and may then attempt to decode each TB PPDU.

[0252] Considering the above-mentioned TB PPDU reception process, the reception of the TB PPDU can be completed only by the information transmitted from the MAC of the receiving device to the PHY layer. Therefore, the receiving device can receive the TB PPDU of each STA without decoding the preamble and SIG fields of the TB PPDU sent by the STA respectively.

[0253] Therefore, the HE-SIG-A field of the 11ax TB PPDU can be configured to include information for assisting the operation of OBSS devices (BSS color, TXOP, and four spatial reuse fields), rather than information required to receive and decode the TB PPDU.

[0254] As described above, unlike the reception process of a general PPDU, reception of a TB PPDU may be performed based on information provided to the PHY by the MAC of the receiving device that is the subject of generating the trigger frame, instead of obtaining information from the preamble and SIG fields of the PPDU being received.

[0255] Therefore, if the STA receiving the trigger frame uses other RUs except the RU allocated by the trigger frame, or encodes the PPDU using other parameter values ​​except the parameter values ​​indicated by the trigger frame, the device that performs reception of the TB PPDU after sending the trigger frame cannot receive and process the TB PPDU.

[0256] If a specific STA generates and UL sends a TB PPDU using RUs other than the RUs allocated by the trigger frame, the PHY of the AP that sends the trigger frame may not be able to separate the TB PPDU sent by the specific STA from the OFDMA TB PPDUs received by multiple STAs. In addition, when a specific STA encodes the PPDU using parameter values ​​other than the parameter values ​​indicated by the trigger frame, the PHY of the AP that sends the trigger frame may fail in decoding although it can separate the TB PPDU of the specific STA from the received OFDMA TB PPDU. In order to prevent the reception failure of the TB PPDU as described above, after receiving the trigger frame, the STA that sends the TB PPDU in response to the trigger frame can be restricted to generate and send the TB PPDU only using the RU allocated to itself and the indicated parameter values.

[0257] As described above, when the STA responds with a TB PPDU after receiving a trigger frame, it is restricted to use only the RUs allocated by the trigger frame and the indicated parameters, which is necessary to ensure that the AP successfully receives and decodes the TB PPDU responded by the STA. However, in the case where a hidden node of the AP exists on the STA side, the STA may not be able to effectively use the RUs allocated to itself.

[0258] Fig.21 Another example of a method of receiving a TB PPDU based on a trigger frame according to an embodiment of the present invention is illustrated.

[0259] Reference Fig.21 ,When the hidden node of the AP exists on the STA side, the STA cannot send the TB PPDU using the RU allocated through the trigger frame of the AP.

[0260] Specifically, the AP may allocate a 996-tone size RU located in the lower 80 MHz band to STA1 through a trigger frame, and may allocate a 242+(242)+484-tone size RU located in the upper 80 MHz band to STA2. In this case, in the 160 MHz band allocated separately to STA1 and STA2, the 20 MHz band (242-tone size RU) not allocated to the two STAs may be a band in which a subchannel determined to be BUSY according to a CCA result performed before the AP sends a trigger frame exists.

[0261] The trigger frame sent by the AP will be received by the STA of the BSS operated by the AP, and STA 1 and STA 2 can identify their own user information field in at least one user information field included in the user information list field of the received trigger frame through the AID field. In this case, STA 1 can identify that the RU allocated to itself is a 996-tone size RU in the lower 80MHz band through the RU allocation subfield present in the confirmed own user information field, and STA 2 can identify that the RU allocated to itself is a 242+(242)+484-tone size RU located in the upper 80MHz band in the same manner as STA 1.

[0262] STA 1 and STA 2, which identify the RU assigned to them through the trigger frame, can perform CCA during SIFS, which is the time interval after receiving the trigger frame until responding with a TB PPDU. In this case, CCA can be ED-based CCA. The operation of STA performing ED-based CCA can be limited to being performed when the CS request subfield appearing in the common information field of the received trigger frame is 1. ED-based CCA may include one or both of energy detection and virtual carrier sensing (NAV) for each 20MHz CCA sensitivity.

[0263] In addition, the STA that performs ED-based CCA after the RU is allocated through the trigger frame can perform ED-based CCA on the entire BW area of ​​the PPDU including the trigger frame, or can perform ED-based CCA only on the subchannel including the RU allocated through the trigger frame.

[0264] If the result of the CCA performed by the STA to which the RU is allocated through the trigger frame is that at least one of the 20 MHz sub-channels where the allocated RU is located is BUSY, the allocated RU cannot be used to perform transmission of the TB PPDU.

[0265] STA 1 and STA 2 can perform CCA on four 20MHz subchannels of the lower 80MHz band and three 20MHz subchannels of the upper 80MHz band respectively. As a result of performing CCA on the subchannels where the RUs are allocated to themselves, both STAs can confirm that some of the subchannels where the RUs are allocated to themselves (1 in the case of STA 1 and 2 in the case of STA 2) are BUSY. In this case, both STA 1 and STA 2 may fail to send TB PPDU.

[0266] As described above, when there is a subchannel considered to be BUSY among the 20MHz subchannels where the RUs to which the STA is allocated through the trigger frame are located, the use of the subchannel considered to be in the IDLE state is also limited. Therefore, the restriction that the STA to which the RUs are allocated through the trigger frame and which transmits the TB PPDU in UL must use all the RUs allocated to itself to transmit the TB PPDU may be the main reason for reducing the efficiency of the UL OFDMA transmission performed by the trigger frame-TB PPDU exchange.

[0267] In order to solve the availability limitation problem of STA regarding RUs allocated by trigger frames as described above, the present invention proposes a process that allows STA to adaptively change the RU to send TB PPDU based on the allocated RU and the CCA result of the 20 MHz subchannel where the allocated RU is located.

[0268] In the present invention, the meaning of "20MHz subchannel existing in the RU" can be used to indicate the 20MHz subchannel where the subchannel corresponding to the RU is located. That is, the number of 20MHz subchannels included in 26, 52, 106, 242-tone size RUs is 1, and the number of 20MHz subchannels included in 484, 996-tone size RUs is 2 and 4, respectively. In this case, the type of RU finally used determined by the STA based on the CCA result can be determined by considering the predetermined RU configuration. The method for determining the type of RU finally used will be described in detail through the embodiments described below. Briefly, according to one aspect of the present invention, the STA can UL send a TB PPDU by using all or part of the IDLE 20MHz subchannels that exist in the allocated RU based on the result of the CCA, instead of the STA to which the RU is allocated directly using the allocated RU through the trigger frame.

[0269] Fig. 22 is another example illustrating a method of receiving a TB PPDU based on a trigger frame according to an embodiment of the present invention.

[0270] Reference Fig. 22, a device that has received a trigger frame may send (respond to) a TB PPDU using only a portion of the RUs allocated through the trigger frame.

[0271] Specifically, each of STA 1 and STA 2 can use only the subchannels in the RU allocated to itself except the subchannels for which the CCA result is considered to be BUSY to send the TB PPDU in UL. As described above, the operation of the STA selectively changing the RU configuration for generating and sending the TB PPDU according to the CCA result for the 20MHz subchannel existing in the RU allocated to itself can be an operation without any performance problem when implemented. This is because, in the process of generating the TB PPDU after the STA receives the trigger frame, by simply adding a process updated according to the CCA result instead of directly using the RU configuration confirmed by the trigger frame, it is possible to achieve such Fig. 22 The operation of the STA is shown.

[0272] As described above, the operation on the STA side can be easily implemented, and Fig. 22 As shown, for an AP, when the RU it allocates to each STA through a trigger frame does not match the RU occupied by a TB PPDU transmitted by each STA, the AP may not be able to successfully decode an OFDMA PPDU (TB PPDU).

[0273] Fig.23 Another example of a method of receiving a TB PPDU based on a trigger frame according to an embodiment of the present invention is illustrated.

[0274] Reference Fig.23 , when the RU allocated by the trigger frame and the RU sending the TB PPDU as a response to the trigger frame have different RU configurations, the AP may not be able to receive UL OFDMA.

[0275] When considering reference Fig. 20 When describing the TB PPDU reception process on the AP side, it can be predicted that the AP's PHY can receive TBPPDU1 of STA 1 through a 996 tone size RU located in the lower 80 MHz frequency band based on the TRIGVECTOR received from the MAC, and receive TB PPDU2 of STA 2 through a 242+484 tone size RU located in the upper 80 MHz frequency band.

[0276] Therefore, when starting to receive the UL OFDMA PPDU, the AP can predict that the lower 80MHz band has 80MHz TBPPDU1 and attempts to decode the 80MHz PPDU, and can predict that the upper 80MHz band has TB PPDU2 at 20+(20)+40MHz and attempts to decode the 20+(20)+40MHz PPDU. In this case, the TB PPDU1 and TB PPDU2 sent by STA 1 and STA 2, respectively, are of a different type from the PPDU that the AP is attempting to decode. Therefore, the AP cannot decode the TB PPDU sent in response to the trigger frame.

[0277] As described above, in order to solve the problem that the AP side cannot decode the TB PPDU sent UL through another RU configuration (rather than the RU configuration allocated by the trigger frame) according to the determination of each STA, it is necessary to allow the AP to identify the type of RU used by each STA. Signaling or a process. Therefore, the present invention provides a method that allows the AP to identify the type (RU configuration) of the TB PPDU being received through the signaling field of the TB PPDU when the AP receives the TB PPDU, and a process for the AP to identify and estimate the type of TB PPDU sent by each STA through the CCA for each 20MHz.

[0278] In order to simplify the following description of the present invention, as described above, the STA to which the RU is allocated by the trigger frame configures and UL transmits the TB PPDU using only some RUs included in the allocated RU according to the CC result or for implementation reasons, which can be referred to as dynamic TB PPDU configuration and UL transmission. In an embodiment of the dynamic TB PPDU configuration, the configuration of the dynamic TB PPDU means that the STA to which the 80MHz RU is allocated configures the TB PPDU by using the 60(20+40)MHz RU except the 20MHz subchannel determined as BUSY as the CCA result for the 80MHz RU. In this case, the RU used by each STA when configuring the dynamic TB PPDU not only excludes the CCA result, but also excludes the type other than some subchannels determined as IDLE among the subchannels in the allocated RU due to the limitation of the M-RU (multiple RU) configuration allowed in the standard or the limitation of implementation. In addition, in addition to the limitation of the CCA result and the M-RU configuration or the limitation of implementation, when the amount of data to be sent is not much, each STA can configure the dynamic TB PPDU by using only some RUs instead of all available RUs.

[0279] <Embodiment of trigger frame format for dynamic TB PPDU>

[0280] After sending the trigger frame, the AP receiving the dynamic TB PPDU as a response to the trigger frame needs to identify the RU configuration that sends the dynamic TB PPDU sent by each STA, instead of relying solely on the RU information allocated to each STA through the trigger frame like the existing 11ax AP. To this end, each STA can include information about the RU that sends the dynamic TB PPDU configured by itself in the preamble, and the AP can confirm the type of the dynamic TB PPDU sent by each STA by receiving / decoding the preamble of the dynamic TB PPDU sent by each STA. In this case, the AP must decode at least one subchannel where the preamble of the dynamic TB PPDU sent by each STA appears before it can confirm the type of the entire RU where the dynamic TB PPDU appears.

[0281] Therefore, when responding to multiple dynamic TB PPDUs through a single trigger frame, the AP must decode the preambles of the multiple dynamic TB PPDUs being responded to separately, and must perform the operation of decoding the multiple preambles in parallel, so this may be an operation that requires a high level of implementation complexity on the AP side.

[0282] If the AP does not have the ability to process the preamble of the dynamic TB PPDU sent from each STA at once, the AP cannot decode the dynamic TB PPDU whose preamble is not properly processed in the dynamic TB PPDU. Therefore, the AP must explicitly indicate to the STA whether it can respond with a dynamic TB PPDU while allocating the RU to the STA through the trigger frame.

[0283] In addition, since reception of the dynamic TB PPDU is performed in the PHY, the MAC of the AP may send a DYNAMIC_RU_LIST indicating whether the dynamic TB PPDU can be received in each RU and a TRIGVECTOR parameter RU_ALLOCATION_LIST to the PHY after configuring a trigger frame and requesting transmission to the PHY.

[0284] Fig.24 An example of a user information field of a trigger frame according to an embodiment of the present invention is illustrated.

[0285] Reference Fig.24 , the STA to which the RU is allocated through the trigger frame can identify whether to allow or refuse to respond with a dynamic TB PPDU through the user-specific field of the trigger frame.

[0286] The reception of a dynamic TB PPDU by an AP is an operation not supported in the prior art 11ax standard and may serve as a factor that increases the implementation complexity of an AP that receives an UL OFDMA PPDU. Therefore, considering the AP's own capabilities, the AP may signal whether a dynamic TB PPDU response is allowed as a response to a trigger frame sent by itself.

[0287] In an embodiment, the AP may use a specific field of the trigger frame to indicate whether a STA that responds to a TB PPDU after receiving the trigger frame is allowed to send a dynamic TB PPDU.

[0288] Specifically, in order to indicate to each STA whether a dynamic TB PPDU response is allowed by using a specific field included in the trigger frame, the AP may use a user information field in the trigger frame.

[0289] like Fig.24 As shown, the user information field of the trigger frame can be composed of AID12, RU allocation, dynamic TB PPDU response, UL FED coding type, UL EHT-MCS, UL DCM, SS allocation / RA-RU information, UL target RSSI, reserved, and trigger-related user information subfields.

[0290] The AID12 field indicates the AIDLSB 12 bits of the STA that is allocated RU through the user information field and needs to respond with a TB PPDU, and the RU allocation subfield indicates the size and position of the RU to be used by the STA that needs to respond with a TB PPDU. In this case, the RU allocation subfield can be interpreted by combining with the UL_BW included in the common information field of the trigger frame.

[0291] In addition, the user information field of the 11be trigger frame is mostly composed of subfields with the same or similar functions as the trigger frame of 11ax, and the RU allocation subfield and SS allocation / RA-RU information subfield can be used to indicate the M-RU (multi-RU) added in 11be and the number of added antennas (16).

[0292] In the subfield of the user information field, the dynamic TB PPDU response subfield may indicate whether the STA that is allocated RU through the user information field and needs to respond with a TB PPDU is allowed to use a dynamic TB PPDU of a part of the allocated RU according to the result of its CCA. In an embodiment, when the dynamic TB PPDU response subfield is set to 1, the STA that received the corresponding user information field may be allowed to respond with a dynamic TB PPDU, and when the subfield is set to 0, responding with a dynamic TB PPDU may be prohibited.

[0293] In another example, the AP may not individually signal each STA whether to allow a dynamic TB PPDU response. In this case, each STA can recognize that a dynamic TB PPDU response is allowed and operate only when it is allocated a SU-RU above 40MHz RU through a trigger frame.

[0294] In another embodiment, the AP may indicate to all STAs whether dynamic TB PPDU response is allowed through the common information field (of the trigger frame) instead of through the user information field of each STA. If dynamic TB PPDU response is allowed through the common information field of the trigger frame, and the STA allocated with RU above 40MHz has the ability to respond to dynamic TB PPDU, the STA may configure dynamic TB PPDU to respond to the trigger frame.

[0295] <Method for determining whether dynamic TB PPDU is allowed>

[0296] In addition to the above limitations related to the decoding capabilities of the AP, there may be situations where dynamic TB PPDU is not allowed. If the RU allocated to a specific STA through a trigger frame is less than 20MHz (242-tone size RU) or equal to 20MHz RU, the STA allocated with the RU may not configure a dynamic TB PPDU.

[0297] Assuming that the STA is allocated a 20MHz RU, the STA performs CCA on the 20MHz subchannel present in the 20MHz RU and determines that the entire 20MHz RU is IDLE or BUSY. Therefore, the STA allocated the 20MHz RU has no reason to dynamically use the RU allocated to it according to the result of the CCA. In addition, even if the CCA result of each RU in the 20MHz RU can be obtained, since the preamble of the TB PPDU must be configured in units of 20MHz, there is a problem that the preamble cannot be sent except for the small RU determined to be BUSY. Similarly, the STA allocated a RU less than 20MHz is also restricted from sending dynamic TB PPDUs for the same reason as the STA allocated the 20MHz RU mentioned above.

[0298] In addition, when the AP allocates the same RU to multiple STAs through a trigger frame, the TB PPDU sent by each STA must have the same preamble and RU configuration and respond. If multiple STAs assigned the same RU respond with dynamic TB PPDUs sent with different RU configurations, the AP receiving the dynamic TB PPDU may not be able to identify the type of dynamic TB PPDU sent by each STA. Therefore, when the AP allocates a specific RU to multiple STAs, the AP can indicate the dynamic TB PPDU response subfield appearing in the user information field of each STA as 0, thereby limiting each STA to not respond to the dynamic TB PPDU with a different RU configuration.

[0299] Alternatively, as another method, when the RU allocated to each STA is an RU of 40MHz or more, the STA can perform a process of checking whether the RU allocated to itself is a MU (multi-user) RU allocated to other STAs except itself. In this case, each STA can respond to the dynamic TB PPDU only when the RU allocated to itself is a SU (single-user) RU allocated only to itself.

[0300] In addition, even if each STA is assigned a different RU, if the assigned different RUs are RUs that exist in the same 80MHz RU boundary, the above STA may be restricted from responding to the dynamic TB PPDU. This may be due to the restriction that different preambles cannot appear in the 80MHz segment. If the AP allocates two 40MHz RUs that exist in the 80MHz segment to two STAs respectively through a trigger frame, when each STA sends a dynamic TB PPDU, a different preamble may be configured to respond. In this case, two different preambles may appear in the 80MHz segment, which may be an operation that violates the principles specified by 11be. In this case, the dynamic TB PPDU response restrictions related to the above-mentioned preamble regulations can be limited and applied to the embodiments related to the preamble configuration of the dynamic TB PPDU in the embodiments of the present invention described below.

[0301] In addition, the operation of the STA to respond to or receive the dynamic TB PPDU may be difficult to implement for a STA with a limited hardware configuration, so the AP and the STA may exchange information about whether the dynamic TB PPDU response is supported in the EHT capability element and information about the supported RU configuration. In this case, when the Dynamic TB PPDU field of the EHT capability element is indicated as 1, it indicates that the corresponding STA can configure and respond to the dynamic TB PPDU.

[0302] <Embodiment of a trigger frame and TB PPDU format for dynamic TB PPDU exchange>

[0303] Fig.25 An example of a method of transmitting a TB PPDU based on a trigger frame according to an embodiment of the present invention is illustrated.

[0304] Reference Fig.25 , the STA to which the RU is allocated through the trigger frame can respond with a dynamic TB PPDU.

[0305] Specifically, it is assumed that the AP allocates RUs through a trigger frame, and STA 1 and STA 2 allocated RUs through the trigger frame perform the same operation as the dynamic TB PPDU response. Fig. 22 The CCA situation for each STA shown in is the same.

[0306] like Fig.25 As shown, each STA can respond to the information about the RU configuration used by itself through the U-SIG field of the dynamic TB PPDU to which it responds. Fig.25 (a) of FIG. 1 shows that STA 1 responds to the dynamic TB PPDU 1 by using the 20+(20)+40MHz RU except the second 20MHz subchannel in the 80MHz RU allocated to itself, and STA 2 responds to the dynamic TB PPDU 2 by using the 20MHz RU located at the lowest frequency position in the RU allocated to itself. In this case, if the AP decodes the preambles appearing in the subchannels of the dynamic TB PPDUs respectively transmitted by STA 1 and STA 2 at least one by one, the AP can recognize that the dynamic TB PPDU 1 of STA 1 will be received in the 20+(20)+40MHz RU existing in the lower 80MHz, and the dynamic TB PPDU 2 of STA 2 will be received in the lower 20MHz RU existing in the upper 80MHz RU.

[0307] As described above, when considering the limited length of the U-SIG field, the method of each STA signaling information for configuring the RU type of the dynamic TB PPDU may limit the representation of some RU types. If the RU allocated to the STA is 320MHz, and the STA can freely use the allocated 320MHz RU in units of 20MHz RU to configure the dynamic TB PPDU, 16 bits must be allocated to accurately represent the type of dynamic TB PPDU that can be configured by the above-mentioned STA allocated 320MHz RU. However, since the U-SIG includes a version-related field (Version independent field), a spatial reuse field for OBSS, a puncturing mode field, etc., 16 bits cannot be allocated as described above to represent the type of dynamic Tb PPDU.

[0308] Therefore, the size of the RU type-related field that can be used to indicate the type of the dynamic TB PPDU can be limited and can have a configuration that excludes signaling for a specific RU combination. However, in 11be, considering the complexity and efficiency of implementation, an RU combination (M-RU) that a single STA can use is defined, and due to the defined RU combination, most dynamic TB PPDU types can be represented even in 4 bits, regardless of the RU size allocated to the STA.

[0309] Fig.26 An example of the format of the U-SIG field of the TB PPDU according to an embodiment of the present invention is illustrated. Fig.26 The format of the U-SIG field of the TB PPDU shown may be based on the premise that the U-SIG of the TB PPDU may have different values ​​in the 80 MHz segment.

[0310] refer to Fig.26 , the U-SIG of the TB PPDU may include a version-independent field. Figure 8 As described in the embodiments of the present invention, the version independent field may be a field commonly included in the next generation WiFi PPDU regardless of the PHY protocol version and the PPDU type.

[0311] In addition, the spatial reuse 1 and 2 fields indicated in the U-SIG of the TB PPDU may indicate a spatial reuse value to be applied to the 80 MHz segment in which the TB PPDU is transmitted.

[0312] In addition, puncturing modes 1 and 2 may appear in the TB PPDU U-SIG, and puncturing mode 1 may be a field in which the UL_Puncturing mode field value sent to each STA through the common information field of the trigger frame is copied / moved as is. The UL_Punturing mode field may be a value of a puncturing mode indicated by the type of UL OFDMA PPDU to be received by the AP as a response to the trigger frame in the process of generating the trigger frame. That is, the puncturing mode 1 field may be information provided to support the operation of other devices similar to the spatial reuse field, and the purpose is not to provide information required for the AP to receive dynamic TB PPDUs. Therefore, the puncturing mode 1 field may be a field having the same value in all (dynamic) TB PPDUs responded to by the trigger frame.

[0313] Meanwhile, the Puncturing Mode 2 field indicates the type of RU used by the STA itself that responds with the dynamic TB PPDU to configure the dynamic TB PPDU, and therefore, the Puncturing Mode 2 field of the (dynamic) TB PPDU sent by different STAs (in different 80MHz segments) may have different values. Fig.28 An embodiment of signaling using the puncturing pattern 2 field is described.

[0314] When the OBSS device detects a preamble of a TB PPDU in a specific segment, the segment location field provides information about the segment number in which the TB PPDU including the detected preamble is located in the operating bandwidth of the AP receiving the TB PPDU. Fig.28 An embodiment of signaling using the segment location field is described below.

[0315] As described above, considering the complexity and efficiency of implementation, the RU combination that the STA that is allocated RU through the trigger frame can use for dynamic TB PPDU configuration can be limited to a specific type. For example, the RU that can be allocated to a single STA through a trigger frame can be limited to small RUs (26, 52, 78, 106 and 132 tone size RUs) and 20, 40, 60, 80, 120 and 160MHz RUs (242, 484, 996, 484+996, 996x2-tone size RUs). That is, 100MHz RUs (996+242-tone size RUs) and 140MHz RUs (242+484+996-tone size RUs) have little gain compared to 80MHz RUs and 120MHz RUs, and can be excluded to increase implementation complexity. In this case, due to the above reasons, the types of RUs allocated to a single STA through a trigger frame of a 240 / 320MHz PPDU can also be limited. In this case, the limited type of RU types can be mandatory multiple RUs.

[0316] According to one embodiment of the present invention, when a single STA configures a dynamic TB PPDU by using a portion of the RU allocated to itself, the configured dynamic TB PPDU can be restricted to have a limited format, and a 4-bit bitmap can be used to signal the dynamic TB PPDU with a limited format.

[0317] Fig. 27 An example of configuration and signaling of resource units for transmission of a TB PPDU according to an embodiment of the present invention is illustrated.

[0318] Reference Fig. 27 , the STA is allocated a 160MHz RU through a trigger frame, and the AP that generates and sends the trigger frame can know the size and position of the RU allocated to the STA.

[0319] If the STA performs CCA on 8 20 MHz subchannels included in the allocated 160 MHz RU after receiving the trigger frame, and if one or both of the two subchannels present at the lowest frequency position are determined to be BUSY, the puncturing pattern 2 of the dynamic TB PPDU U-SIG may be represented as 0111. In this case, even when only one of the two subchannels present at the lowest frequency position is BUSY, the STA may configure the dynamic TB PPDU using a 120 MHz RU (484+996-tone size RU) other than the above two subchannels in the allocated 160 MHz RU.

[0320] In another embodiment, as a result of performing CCA on 8 20 MHz subchannels included in a 160 MHz RU allocated to a STA, if only 80 MHz RUs are available due to the above-mentioned RU type restriction, the Puncturing Mode 2 field may be set to 0011 or 1100, and the STA may configure and UL send a dynamic TB PPDU using only 80 MHz RUs.

[0321] When considering the puncturing mode 2 (RU structure of dynamic TB PPDU) signaling method using a 4-bit size bitmap of the present invention, the minimum size of the RU that the STA can indicate using puncturing mode 2 is 1 / 4 of the RU size allocated to itself. Therefore, as in the present embodiment, when the STA is allocated a 160MHz RU and only one of the 8 subchannels included in the RU is determined to be IDLE, the above STA may need to abandon UL transmission using the dynamic TB PPDU.

[0322] Fig.28 An example of transmitting a puncture pattern and a segment position through TB ​​PPDU signaling according to an embodiment of the present invention is illustrated.

[0323] Reference Fig.28 , the STA can receive the allocation of RU through a trigger frame sent in the 160 MHz frequency band, and the two STAs can send a response to the trigger frame through a dynamic TB PPDU of a U-SIG field including a puncturing pattern and a segment position field.

[0324] exist Fig.28 STA 1 is allocated the 80MHz RU corresponding to the segment 1 located at the low frequency through the trigger frame, and STA 2 is allocated the 20+(20)+40MHz RU included in the segment 2 located at the high frequency through the above trigger frame. STA 1 and STA 2 can configure and UL send dynamic TB PPDU1 and PPDU2 by using 20+(20)+40MHz RU and 20MHz RU respectively according to the CCA result and the restriction of RU type.

[0325] In this case, the puncture pattern 1 field included in the U-SIG field of the dynamic TB PPDU respectively transmitted by STA 1 and STA 2 has the same value, while the puncture pattern 2 field and the segment position field may be set to have different values.

[0326] The puncturing mode 1 field included in the dynamic TB PPDU is a value indicated by the common information field of the trigger frame, and as described above, indicates the type information of the UL OFDMA PPDU predicted to be responded to by the trigger frame. Therefore, in all TB PPDUs responded by a single trigger frame, the puncturing mode 1 field has the same value.

[0327] As reference Fig. 27 As described in the embodiment of the present invention, the configuration of the puncturing pattern 2 field can be signaled with different values ​​to indicate the type of RU used by each STA itself. Therefore, STA 1 signals by setting the puncturing pattern 2 field to 1011 to indicate that its dynamic TB PPDU1 is configured using the 20+(20)+40MHz RU located in segment 1, and STA 2 signals by setting the puncturing pattern 2 field to 1000 to indicate that the dynamic TB PPDU2 is configured using 20MHz located at the lowest frequency of segment 2 where the RU allocated to itself is located.

[0328] In addition, each STA can use the segment position field to indicate the information that the TB PPDU transmitted by itself is located in which segment in the BW in which the TB PPDU responded to by ULOFDMA appears. The segment position field can be provided so that the STA that detects the preamble of a specific TB PPDU can confirm the information about the frequency domain in which the TB PPDU transmitted together with the above TB PPDU is located. In this case, the segment position field can be interpreted together with the BW field, which is another field included in the TB PPDU U-SIG. In an embodiment, if the STA confirms that the BW of the TB PPDU is 160MHz in the preamble detected by itself and the segment position field is 00, the STA can confirm that the TB PPDU detected by itself or the TB PPDU responded to together with the detected TB PPDU is transmitted on the 160MHz BW, and the position of the detected TB PPDU is located at 80MHz at the low frequency.

[0329] The embodiment of the present invention considers a 2-bit embodiment of the segment position field, so the 4 segments included in the highest 320MHz PPDU can be represented as 00, 01, 10, and 11 respectively starting from the segment located at the low frequency. Fig. 27As shown in the embodiment, if a specific STA is allocated RU through two segments, the specific STA can set the segment position field included in the U-SIG field of the TB PPDU to different values ​​(for example, 00, 01) according to the position of each segment.

[0330] As described above, the STA responding to the dynamic TB PPDU has a procedure of not configuring the TB PPDU U-SIG using the value indicated in the trigger frame requesting the dynamic TB PPDU, but configuring the U-SIG field after determining the CCA result and RU configuration performed on itself.

[0331] Therefore, the operation of the STA responding to the dynamic TB PPDU may become more complicated compared to the operation of the STA responding to the 11ax TB PPDU, and in this case, it may be difficult to respond to the TB PPDU within the predetermined time (SIFS after the trigger frame) due to delay.

[0332] To solve the above problem, when the AP allows dynamic TB PPDU response to one or more STAs through a trigger frame, the AP can indicate to start the TB PPDU response at another time (not after SIFS). For example, when the AP indicates the delayed response field as 1 through the common information field of the trigger frame, the STA receiving the trigger frame can respond to the TB PPDU after PIFS instead of SIFS.

[0333] exist Fig.28 In the embodiment, the dynamic TB PPDU1 and 2 received as a response to the trigger frame may have different configurations of the U-SIG field, and in order for the AP to identify the RU type in which the dynamic TB PPDU1 and 2 are sent, at least one subchannel in which each of the two dynamic TB PPDU1 and 2 appears must be decoded. However, the AP cannot know which subchannel included in the RU allocated to each STA by itself is excluded in the process of responding to each dynamic TB PPDU. Therefore, in the implementation on the AP side, it may be difficult to decode at least one of the subchannels in which each dynamic TB PPDU appears one by one. In order to solve this problem, it is necessary to pre-set the subchannel that must be occupied when responding to the dynamic TB PPDU.

[0334] Fig.29 An example of setting and using a subchannel for TB PPDU transmission according to an embodiment of the present invention is illustrated.

[0335] Reference Fig.29, the AP allocates one 80MHz RU in each segment to each of STA 1 to STA 4 through a 320MHz trigger frame, and considers the case where each STA is allowed to respond to a dynamic TB PPDU. The AP can separately indicate the subchannel that each STA must occupy when responding to a dynamic TB PPDU. For example, in Fig.29 , it is shown that the AP instructs STA 1 to occupy the third subchannel and instructs STA2 to 3 to occupy the first subchannel respectively, and each STA intentionally occupies the subchannel indicated by the AP among the four subchannels of the segment where its RU is located in response to the dynamic TB PPDU. In the case of STA 4 allocated with an 80MHz RU located in segment 4, since the CCA result of the first subchannel indicated by the AP (the subchannel located at the lowest frequency in the segment) is determined to be BUSY as a result of CCA, the 60MHz RU other than the subchannel determined to be BUSY cannot be used, and the dynamic TB PPDU transmission is abandoned.

[0336] As described above, when a STA responding to a dynamic TB PPDU is indicated (by the AP) as having to occupy or set a pre-agreed mandatory subchannel, the AP can reduce a lot of burden by performing an operation of receiving at least one preamble of a dynamic TB PPDU that responds simultaneously. In this case, the mandatory subchannel of the main 80MHz segment can be fixed to the P20 channel. That is, when a STA to which an RU including a main 20MHz subchannel is allocated configures a dynamic TB PPDU, the configuration of a dynamic TB PPDU that does not include the main 20MHz may be restricted.

[0337] Therefore, as described above, the AP can reduce the burden of receiving the preamble by setting a mandatory subchannel according to its own capabilities, or can allow the dynamic TB PPDU to be responded to within its supportable range by limiting the number of STAs that allow dynamic TB PPDUs.

[0338] <Embodiment of a process for receiving a dynamic TB PPDU>

[0339] The above-mentioned dynamic TB PPDU related embodiments describe the invention-related TB PPDU format and the operation of STAs (AP and non-AP) for obtaining information required for the AP to receive the dynamic TB PPDU by decoding the preamble of the TB PPDU transmitted by each STA through UL.

[0340] Another implementation method of the present invention provides a method for the AP to identify the RU configuration of the dynamic TB PPDU sent by each STA. According to the embodiment of the present invention described later, the AP can confirm the appearance of the TB PPDU received in response to the trigger frame sent by itself based on the strength of the received signal, and compare it with the RU information allocated to each STA, thereby identifying the RU configuration of the dynamic TB PPDU sent by each STA UL.

[0341] Describing the reception method of the dynamic TB PPDU according to the present invention in more detail, since the AP allocates RU to each STA through a trigger frame, the AP can calculate the reception time and BW of the TB PPDU predicted to be received based on the information of the trigger frame generated by itself. In addition, in the TB PPDU predicted to be received, the position information of the TB PPDU sent by each STA UL can be known in advance.

[0342] As described above, considering the situation that the AP knows the position of the RU of the TB PPDU to be sent by each STA, when receiving the TB PPDU in response to the trigger frame, the AP can determine whether the predicted TB PPDU appears by attempting signal detection of the subchannel predicted to appear as the TB PPDU, or determine whether some subchannels are not used, and by confirming that the RU allocated to a specific STA is not used, the AP can recognize that the above-mentioned unused RU is excluded from the TB PPDU configuration. As a simple example, the AP can allocate an 80MHz RU to a specific STA through a trigger frame, and then it can be predicted that an 80MHz TB PPDU will be responded to in response to the trigger frame. In this case, signal detection can be performed on 4 subchannels in the 80MHz RU predicted to be responded to the TB PPDU, and as a result of the signal detection, when a signal is detected only in 3 subchannels, it can be confirmed that the remaining 1 subchannel other than the 3 subchannels where the signal is detected is a subchannel excluded in the process of the STA configuring the dynamic TB PPDU.

[0343] As described above, when the AP identifies the type of TB PPDU to which each STA responds by using signal detection, the STA that responds to the dynamic TB PPDU after receiving the trigger frame does not need to separately provide the AP with information related to the RU configuration of the dynamic TB PPDU it sends.

[0344] In another aspect of the effects that can be obtained using the present invention, the AP can stop additional processing for a TB PPDU determined to be undecodable among TB PPDUs transmitted by each STA based on a signal detection result for the received TB PPDU.

[0345] Fig.30 An example of detecting a signal of a TB PPDU in response to a trigger frame according to an embodiment of the present invention is illustrated.

[0346] Reference Fig.30 (a), the AP allocates the 80MHz RU of segment 1 and the 20+(20)+40MHz RU of segment 2 to STA 1 and STA 2 respectively through a 160MHz trigger frame (allowing dynamic TB PPDU response), and STA 1 and STA 2 that receive the trigger frame respond to dynamic TB PPDU1 and 2 respectively.

[0347] In this case, since the AP already knows that it will receive a TBPPDU at a BW of 160 MHz after sending a trigger frame, the AP can attempt to perform signal detection for identifying the RU configuration for receiving dynamic TB PPDUs. In this case, the signal detection method performed by the AP can be similar to that of every 20 MHz CCA.

[0348] When performing signal detection, the AP can use information about the timing of receiving the TB PPDU and predicting the BW at which the TB PPDU will be received. In the prior art 11ax standard, a STA that is allocated an RU through a trigger frame must respond to the TB PPDU using the allocated RU after SIFS. When taking into account this time specification for the TB PPDU response, the AP can predict that the TB PPDU will be received after a specific time (e.g., positive propagation delay (SIFS)) from the transmission end time of the trigger frame after sending the trigger frame.

[0349] Therefore, the AP can specify the range (frequency and time) of the signal detection operation by using the predicted BW information and the predicted reception timing information of the predicted TB PPDU. In this case, the AP can attempt to perform signal detection in the partial time interval in which the leading edge of the TB PPDU is predicted to be detected based on the reception time information of the predicted reception.

[0350] Fig.30 (b) shows an example of a detection result obtained when the AP performs signal detection for the TB PPDU. Fig.30 As shown in (a), when STA 1 uses 20+(20)+40MHz RU and STA 2 uses 20MHz RU to respond to dynamic TB PPDU1 and 2, the result of the AP's signal detection measures a high signal level in the subchannel used when each STA configures a dynamic TB PPDU, and measures a low signal level in the subchannel not used for dynamic TB PPDU transmission.

[0351] The AP can determine whether to start receiving a TB PPDU in each subchannel by considering the signal strength detected in each subchannel. As a simple example, Fig.30 As shown in (b), the AP can perform the above-mentioned signal detection based on whether the signal detected in each subchannel exceeds a specific threshold. In this case, since the signal detection performed by the AP can be performed according to the timing of the preamble of the received TB PPDU, it is different from the general every 20MHz CCA, and it can be performed in a PD (preamble detection) manner or ED (energy detection) and use a value different from the ED threshold used for general PIFS-based channel access to perform signal detection.

[0352] As described above, after the AP confirms the subchannel where the reception of the TB PPDU starts by using signal detection, the AP may predict the RU configuration of the dynamic TB PPDU transmitted by each STA based on the reception pattern of the confirmed TB PPDU.

[0353] exist Fig.30 As a result of signal detection, the AP may determine that the TB PPDU is represented as 1011 in segment 1 and as 1000 in segment 2. In this case, since the 80 MHz RU of segment 1 is allocated to STA 1 by the trigger frame, the AP may recognize the response of the dynamic TB PPDU by using the 20+(20)+40 MHz RU excluding one subchannel in the 80 MHz RU allocated to STA 1. In this case, the determination of the dynamic TB PPDU type of STA 2 may be performed in the same manner as the recognition process of the dynamic TB PPDU of STA 1.

[0354] The dynamic TB PPDU type identification process performed by the AP's PHY will be briefly described. The AP's PHY may receive a request for sending a trigger frame from the MAC, and then receive RU_ALLOCATION_LIST and DYNAMIC_RU_LIST parameters, etc. through the TRIGVECTOR. Then, the PHY attempts to detect the signal of the TB PPDU based on the time when the TB PPDU is predicted to be responded, and determines whether the TB PPDU is received in each subchannel. In this case, signal detection may be performed only on the subchannel that can receive the dynamic TB PPDU based on the information of the DYNAMIC_RU_LIST parameter.

[0355] Based on the result of the above signal detection, the AP's PHY can modify the STA's RU configuration confirmed by the RU_ALLOCATION_LIST parameter, as a result, even if a dynamic TB PPDU is responded to by using an RU with a configuration different from the RU allocated by the MAC through the trigger frame, the PHY can properly separate and decode the TB PPDU of each STA.

[0356] According to the above-described embodiment of the present invention, the AP can autonomously receive a dynamic TB PPDU responded to by each STA without using additional signaling of the TB PPDU U-SIG. Fig.30 The signal detection method shown in (b) may not be accurate enough, so the AP may erroneously determine the subchannel on which the TB PPDU is received. Therefore, in order to improve the accuracy of signal detection, a signal detection method applied by adaptively adjusting the threshold may be required.

[0357] Fig.31 An example of applying different thresholds to a predicted reception area in a signal detection process for a TB PPDU according to an embodiment of the present invention is illustrated.

[0358] Reference Fig.31 , in the signal detection process for confirming whether the TB PPDU is received, different thresholds may be applied to areas where the TB PPDU from different STAs is predicted to be received.

[0359] exist Fig.31 In the example, the AP may perform signal detection by applying different thresholds to RUs assigned to different STAs. It may be assumed that after the AP sends a trigger frame, it is predicted that a TB PPDU1 response of STA 1 will be received in segment 1, and a TB PPDU2 response of STA 2 will be received in segment 2. In this case, the AP may determine whether TB PPDU1 occurs by applying a threshold of -x dBm to the four subchannels where TB PPDU1 is predicted to be received, and may apply a threshold of -y dBm to the four subchannels where TB PPDU2 is predicted to be received.

[0360] As described above, in order to detect TB PPDU of different STAs, the reason for using different thresholds is that each STA receiving the trigger frame may have a different distance from the AP, and the UL target RSSI value indicated by the AP through the user information field of the trigger frame may be different.

[0361] If the AP indicates that STA 1 indicates that the UL target RSSI is 90 and meets -20dBm, the signal received at -40dBm may not be the signal detected from the TB PPDU responded by STA 1. On the other hand, if the AP indicates that STA 2 indicates that the UL target RSSI is 0 and meets -110dBm, the signal detection result using the -40dBm threshold can ignore the TBPPDU signal responded by STA 2.

[0362] Therefore, the AP may consider the target RSSI value indicated to each STA and apply different thresholds when detecting the TB PPDU to which each STA responds. To this end, the AP's MAC may transmit RU(subchannel)_(target) RSSI_LIST in a TRIGVECTOR transmitted to the PHY.

[0363] According to the above embodiment of the present invention, different target RSSI values ​​can be used to perform signal detection for the TBPPDU of the response. However, if signal interference occurs in some subchannels where signal detection is performed due to other devices, the signal detection results for some of the above word signals may be confirmed as different from the reception type of the actual TB PPDU.

[0364] In order to correct a signal detection error caused by a signal of another device, the AP may determine whether a TB PPDU occurs based on a threshold during signal detection, while additionally confirming whether a signal with a predetermined strength is received in a subchannel where a TB PPDU response of each STA is predicted to be received.

[0365] This is because, in the WiFi standard, when the PPDU transmitted by the STA (AP, non-AP) has a bandwidth exceeding 20MHz, it is recommended that the strength of the signal transmitted by the PPDU in each subchannel is constant (for example, maximum distortion +-4dB), so if there is a subchannel having a predetermined strength difference from the strength of the signal determined in other subchannels among the signals determined in each subchannel, it can be determined that the signal detected in the subchannel is received from other devices. At this time, the method of detecting the signal received from other devices by comparing the strength of the signal can be called a signal detection error method using the flatness of the signal.

[0366] Fig.32 An example of an error correction method for signal detection according to an embodiment of the present invention is illustrated.

[0367] Reference Fig.32 , the AP performs signal detection to check the RU configuration of the dynamic TB PPDU of STA 1 and STA 2, and uses different thresholds for the subchannels predicted to receive the TB PPDU of each STA.

[0368] In this case, in segment 2 where the TB PPDU of STA 2 is predicted to be received, a non-TB PPDU signal higher than a threshold value -y dBm set for the AP to detect the TB PPDU of STA 2 may be detected.

[0369] However, the AP's PHY can confirm that the strength of the signal confirmed in the first (leftmost in the figure) subchannel among the signals detected from segment 2 is different from the strength of the signals confirmed in the remaining 2nd, 3rd, and 4th subchannels, and can recognize based on this that the signals detected in the first subchannel and the remaining subchannels are different signals from each other. In this case, the AP can attempt to decode both signals to confirm whether the dynamic TB PPDU sent by STA 2UL is a 20MHz TB PPDU appearing in the first subchannel or a 20+40MHz TB PPDU using the remaining three subchannels.

[0370] Therefore, according to an embodiment of the present invention, the AP can use signal detection to identify the RU configuration of the dynamic TBPPDU sent by each STA, and can solve errors that may occur during the signal detection process by using an error detection method that uses adaptive threshold adjustment and WiFi signal flatness.

[0371] Fig.33 is a flowchart illustrating an example of a method in which a non-AP STA transmits a response frame to a trigger frame according to an embodiment of the present invention.

[0372] Reference Fig.33 , when receiving a trigger frame indicating transmission of a TB PPDU from the AP, the non-AP STA may generate a TB PPDU in response according to the type and format of the TB PPDU to be responded.

[0373] Specifically, the non-AP STA may receive a trigger frame indicating the transmission of the TB PPDU from the AP (S33010). The trigger frame may include a common information field, which includes a first plurality of spatial reuse fields. In addition, the trigger frame may also include an additional information field, which includes a second plurality of spatial reuse fields, and identify whether the trigger frame includes the additional information field based on the identification information of the trigger frame.

[0374] That is, it may be identified whether the trigger frame includes the second plurality of spatial reuse fields according to identification information included in the trigger frame.

[0375] For example, as described above, the trigger frame may include a first plurality of spatial reuse fields (spatial reuse fields 1 to 4) in the common information field, and based on identification information (for example, whether the value of a specific field of the common information field is '1' or whether the value of the AID of the additional information field is '2007', etc.), the trigger frame may include an additional information field including a second plurality of spatial reuse fields (spatial reuse fields 5 to 8).

[0376] The trigger frame can be configured with Fig. 9 and Fig.11 For example, the trigger frame may include at least one of a common information field, an additional information field, and a user information field, and the configuration of the additional information field and / or the user information field may vary according to the type and / or format of the trigger frame.

[0377] In this case, the user information field for each non-AP STA may be an EHT format or a HE format according to the format of the TBPPDU indicated by the trigger frame.

[0378] In this case, when the location of the RU for transmitting the TB PPDU as a response to the trigger frame is in the high frequency band (or primary BW) or the TB PPDU is an HE TB PPDU, the first plurality of spatial reuse fields included in the common information field can be used to generate the HE TB PPDU. That is, the first plurality of spatial reuse fields can be encoded into the spatial reuse field of the TB PPDU.

[0379] When the location of the RU for transmitting the TB PPDU as a response to the trigger frame is in the low frequency band (or primary BW or secondary BW) or the TB PPDU is an EHT TB PPDU, the second plurality of spatial reuse fields for spatial reuse of the second bandwidth included in the additional information field may be used to generate the EHT TB PPDU. That is, the second plurality of spatial reuse fields may be encoded into the spatial reuse field of the TB PPDU.

[0380] Alternatively, depending on a format associated with the trigger frame (eg, a format of a user information field), the first plurality of spatial reuse fields or the second plurality of spatial reuse fields may be used to generate a TB PPDU as a response frame.

[0381] For example, when the format associated with the trigger frame is the HE format (for example, when the format of the user information field is the HE format), the TB PPDU as the response frame is generated as the HE TB PPDU by using the first plurality of spatial reuse fields. However, when the format associated with the trigger frame is the EHT format (for example, when the format of the user information field is the EHT format), the TB PPDU as the response frame is generated as the EHT TB PPDU by using the second plurality of spatial reuse fields.

[0382] Subsequently, the non-AP STA may generate a response frame based on information obtained from the first plurality of spatial reuse fields or the second plurality of spatial reuse fields in response to the trigger frame ( S33020 ).

[0383] That is, the non-AP STA may determine the format of the response frame for the trigger frame, and generate a TB PPDU as a response frame according to the determined format. In this case, the TB PPDU as a response frame may be generated based on information obtained from the first plurality of spatial reuse fields or the second plurality of spatial reuse fields. It may be determined based on the format associated with the trigger frame whether the response frame is generated based on the first plurality of spatial reuse fields or the second plurality of spatial reuse fields. For example, if the format of the user information field of the trigger frame is the HE format, the format of the TB PPDU may be determined as the HE TB PPDU, and the TB PPDU may be generated based on the first plurality of spatial reuse fields. That is, the response frame may be generated based on information obtained from the first plurality of spatial reuse fields or the second plurality of spatial reuse fields.

[0384] The first multiple spatial reuse fields or the second multiple spatial reuse fields for generating the TB PPDU may also be selected according to the position of the RU allocated for the transmission of the TB PPDU indicated by the trigger frame. That is, if the position of the RU is in the high frequency band (or primary BW), the TB PPDU may be generated based on the first multiple spatial reuse fields, and if the position of the RU is in the low frequency band (or secondary BW), the TB PPDU may be generated based on the second multiple spatial reuse fields.

[0385] Subsequently, the non-AP STA may send a response frame generated based on information obtained from the first plurality of spatial reuse fields or the second plurality of spatial reuse fields in response to the trigger frame (S34030). Whether the response frame is generated based on the first plurality of spatial reuse fields or the second plurality of spatial reuse fields may be determined based on a format associated with the trigger frame.

[0386] When the format associated with the trigger frame is an EHT (Extreme High Throughput) format, the response frame is generated based on information obtained from the second plurality of spatial reuse fields.

[0387] Furthermore, when the format associated with the trigger frame is a HE (High Efficiency) format, a response frame is generated based on information obtained from the first plurality of spatial reuse fields.

[0388] Furthermore, whether to generate the response frame based on information obtained from the first plurality of spatial reuse fields or based on information obtained from the second plurality of spatial reuse fields may be determined based on a position of the transmitted response frame on the frequency axis of the resource unit.

[0389] The trigger frame may include at least one of a bandwidth field, an additional bandwidth field, a resource allocation field indicating a resource unit for sending a response frame, and a puncturing pattern field indicating whether puncturing is performed in the bandwidth indicated by the bandwidth field and / or the additional bandwidth field and the puncturing position.

[0390] In addition, the non-AP STA can identify the resource unit for sending a response frame based on the resource allocation field included in the trigger frame, and can generate a response frame based on the information obtained from the first plurality of spatial reuse fields or the second plurality of spatial reuse fields according to the position of the sent response frame on the frequency axis of the resource unit.

[0391] When the response frame is generated based on the second plurality of spatial reuse fields, the response frame may be transmitted through a bandwidth indicated by a bandwidth field included in the common information field and an additional bandwidth field included in the additional information field.

[0392] The response frame may include a plurality of spatial reuse fields, and each of the plurality of spatial reuse fields may be set based on information obtained from a corresponding first plurality of spatial reuse fields or a second plurality of spatial reuse fields.

[0393] Whether the trigger frame includes the additional information field may be identified according to a value of a specific subfield indicating whether the additional information field is included in the common information field and / or whether a value of an identifier of the additional information field is set to a specific value.

[0394] In addition, as described above, the response frame may be transmitted in the form of a TB PPDU, and the TB PPDU may be combined with at least one TB PPDU transmitted by at least one non-ATP STA that is instructed to transmit the TB PPDU by the trigger frame, and transmitted in the form of an A (aggregate)-PPDU. In this case, at least one TB PPDU is generated based on the first plurality of spatial reuse fields or the second plurality of spatial reuse fields, and the TB PPDU and the at least one TB PPDU are generated based on different spatial reuse fields.

[0395] Fig.34 is a flowchart illustrating an example of a method in which an AP STA receives a response frame to a trigger frame according to an embodiment of the present invention.

[0396] Reference Fig.34 , the AP may transmit a trigger frame indicating the transmission of a TB PPDU, and may receive a TB PPDU as a response to the trigger frame from at least one non-AP STA. In this case, if the number of TB PPDUs transmitted from at least one non-AP STA is 2 or more, the TB PPDUs may be aggregated and transmitted in the form of an A-PPDU. In addition, the TB PPDU may have different formats (e.g., HE TB PPDU, EHT TB PPDU, etc.).

[0397] Specifically, the AP may generate and send a trigger frame indicating the transmission of the TB PPDU (S34010). The trigger frame may include a common information field, which includes a first plurality of spatial reuse fields. In addition, the trigger frame may also include an additional information field, which includes a second plurality of spatial reuse fields, and whether the trigger frame includes the additional information field is identified based on the identification information of the trigger frame.

[0398] That is, it may be identified whether the trigger frame includes the second plurality of spatial reuse fields according to identification information included in the trigger frame.

[0399] For example, as described above, the trigger frame may include a first plurality of spatial reuse fields (spatial reuse fields 1 to 4) in the common information field, and based on identification information (for example, whether the value of a specific field of the common information field is '1' or whether the value of the AID of the additional information field is '2007', etc.), the trigger frame may include an additional information field including a second plurality of spatial reuse fields (spatial reuse fields 5 to 8).

[0400] The trigger frame can be configured with Fig. 9 and Fig.11 For example, the trigger frame may include at least one of a common information field, an additional information field, and a user information field, and the configuration of the additional information field and / or the user information field may vary according to the type and / or format of the trigger frame.

[0401] In this case, the user information field for each non-AP STA may be in the EHT format or the HE format according to whether the format of the TBPPDU indicated by the trigger frame is an EHT format or a HE format.

[0402] In this case, when the location of the RU of the TB PPDU transmitted as a response to the trigger frame is in the high frequency band (or primary BW) or the TB PPDU is an HE TB PPDU, the first plurality of spatial reuse fields included in the common information field can be used to generate the HE TB PPDU. That is, the first plurality of spatial reuse fields can be encoded into the spatial reuse field of the TB PPDU.

[0403] When the location of the RU of the TB PPDU transmitted as a response to the trigger frame is in the low frequency band (or primary BW or secondary BW) or the TB PPDU is an EHT TB PPDU, the EHT TB PPDU may be generated using the second plurality of spatial reuse fields for spatial reuse of the second bandwidth included in the additional information field. That is, the second plurality of spatial reuse fields may be encoded into the spatial reuse field of the TB PPDU.

[0404] Alternatively, according to a format associated with the trigger frame (eg, a format of a user information field), a TB PPDU as a response frame may be generated using the first plurality of spatial reuse fields or the second plurality of spatial reuse fields.

[0405] For example, when the format associated with the trigger frame is the HE format (for example, when the format of the user information field is the HE format), the TB PPDU as the response frame is generated as the HE TB PPDU by using the first plurality of spatial reuse fields. However, when the format associated with the trigger frame is the EHT format (for example, when the format of the user information field is the EHT format), the TB PPDU as the response frame is generated as the EHT TB PPDU by using the second plurality of spatial reuse fields.

[0406] Then, the AP may receive at least one response frame (TB PPDU) in response to the trigger frame from at least one non-AP STA (S34020). In this case, the TB PPDU may be generated based on information obtained from the first plurality of spatial reuse fields or the second plurality of spatial reuse fields.

[0407] A TB PPDU as a response frame may be generated based on information obtained from the first plurality of spatial reuse fields or the second plurality of spatial reuse fields. Whether the response frame is generated based on the first plurality of spatial reuse fields or the second plurality of spatial reuse fields may be determined based on a format associated with the trigger frame. For example, when the format of the user information field of the trigger frame is the HE format, the format of the TB PPDU may be determined as the HE TB PPDU, and the TB PPDU may be generated based on the first plurality of spatial reuse fields. That is, a response frame may be generated based on information obtained from the first plurality of spatial reuse fields or the second plurality of spatial reuse fields.

[0408] The first multiple spatial reuse fields or the second multiple spatial reuse fields for generating the TB PPDU may also be selected according to the position of the RU allocated for the transmission of the TB PPDU indicated by the trigger frame. That is, if the position of the RU is in the high frequency band (or primary BW), the TB PPDU may be generated based on the first multiple spatial reuse fields, and if the position of the RU is in the low frequency band (or secondary BW), the TB PPDU may be generated based on the second multiple spatial reuse fields.

[0409] Whether to generate the response frame based on the first plurality of spatial reuse fields or the second plurality of spatial reuse fields may be determined based on a format associated with the trigger frame.

[0410] When the format associated with the trigger frame is an EHT (Extreme High Throughput) format, the response frame is generated based on information obtained from the second plurality of spatial reuse fields.

[0411] In addition, when the format associated with the trigger frame is the HE (High Efficiency) format, the response frame is generated based on the information obtained from the first plurality of spatial reuse fields. That is, the response frame can be generated based on the information obtained from the first plurality of spatial reuse fields or the second plurality of spatial reuse fields.

[0412] The first multiple spatial reuse fields or the second multiple spatial reuse fields for generating the TB PPDU may also be selected according to the position of the RU allocated for the transmission of the TB PPDU indicated by the trigger frame. That is, if the position of the RU is in the high frequency band (or primary BW), the TB PPDU may be generated based on the first multiple spatial reuse fields, and if the position of the RU is in the low frequency band (or secondary BW), the TB PPDU may be generated based on the second multiple spatial reuse fields.

[0413] When the format associated with the trigger frame is an EHT (Extreme High Throughput) format, the response frame is generated based on information obtained from the second plurality of spatial reuse fields.

[0414] Furthermore, when the format associated with the trigger frame is a HE (High Efficiency) format, a response frame is generated based on information obtained from the first plurality of spatial reuse fields.

[0415] Furthermore, whether to generate the response frame based on information obtained from the first plurality of spatial reuse fields or based on information obtained from the second plurality of spatial reuse fields may be determined based on a position of the transmitted response frame on the frequency axis of the resource unit.

[0416] The trigger frame may include at least one of a bandwidth field, an additional bandwidth field, a resource allocation field indicating a resource unit for sending a response frame, and a puncturing pattern field indicating whether puncturing is performed in the bandwidth indicated by the bandwidth field and / or the additional bandwidth field and the puncturing position.

[0417] In addition, the non-AP STA can identify the resource unit for sending a response frame based on the resource allocation field included in the trigger frame, and can generate a response frame based on the information obtained from the first plurality of spatial reuse fields or the second plurality of spatial reuse fields according to the position of the sent response frame on the frequency axis of the resource unit.

[0418] When the response frame is generated based on the second plurality of spatial reuse fields, the response frame may be transmitted through a bandwidth indicated by a bandwidth field included in the common information field and an additional bandwidth field included in the additional information field.

[0419] The response frame may include a plurality of spatial reuse fields, and each of the plurality of spatial reuse fields may be set based on information obtained from a corresponding first plurality of spatial reuse fields or a second plurality of spatial reuse fields.

[0420] Whether the trigger frame includes the additional information field may be identified according to a value of a specific subfield indicating whether the additional information field is included in the common information field and / or whether a value of an identifier of the additional information field is set to a specific value.

[0421] In addition, as described above, the response frame may be transmitted in the form of a TB PPDU, and the TB PPDU may be combined with at least one TB PPDU transmitted by at least one non-ATP STA that is instructed to transmit the TB PPDU by the trigger frame, and transmitted in the form of an A (aggregation)-PPDU. In this case, at least one TB PPDU is generated based on the first plurality of spatial reuse fields or the second plurality of spatial reuse fields, and the TB PPDU and the at least one TB PPDU are generated based on different spatial reuse fields.

[0422] The description of the present invention is for illustrative purposes, and those skilled in the art to which the present invention belongs will be able to understand that the present invention can be easily modified into other specific forms without changing the technical ideas or its essential features. Therefore, it should be understood that the embodiments described above are intended to be illustrative in various senses, rather than restrictive. For example, each component described as a single type can be implemented in a distributed manner, and similarly, the components described in a distributed manner can also be implemented in a combined form.

[0423] The scope of the present invention is indicated by the claims to be described below, rather than the detailed description, and the meaning and scope of the claims and all changes or modifications derived from equivalents thereof should be construed as being included in the scope of the present invention.

Claims

1. A terminal in a wireless communication system, the terminal comprising: Communication module; as well as a processor configured to control the communication module, Wherein, the processor is configured to: receiving a trigger frame including a common information field from an access point AP, and sending a trigger-based TB PPDU in response to the trigger frame, Wherein, when the type associated with the trigger frame is a high-efficiency HE type, the common information field includes a first plurality of spatial reuse fields used to generate the TB PPDU, and Only when the type associated with the trigger frame is an extremely high throughput (EHT) type, the trigger frame further includes a second plurality of spatial reuse fields used to generate the TB PPDU.

2. The terminal according to claim 1, in, When the type associated with the trigger frame is the EHT type, the TB PPDU is generated depending on the second plurality of spatial reuse fields included in the trigger frame.

3. The terminal according to claim 1, in, When the type associated with the trigger frame is the HE type, the TB PPDU is generated depending on the first plurality of spatial reuse fields included in the common information field.

4. The terminal according to claim 1, in, When the type associated with the trigger frame is the HE type, the trigger frame does not include the second plurality of spatial reuse fields.

5. The terminal according to claim 1, in, The trigger frame further includes identification information used to indicate whether the type related to the trigger frame is the EHT type or the HE type.

6. The terminal according to claim 1, in, A location of a frequency band to which a resource unit to transmit the TB PPDU is allocated varies according to whether the TB PPDU is generated using the first plurality of spatial reuse fields or the second plurality of spatial reuse fields.

7. The terminal according to claim 6, in, When the TB PPDU is generated using the second plurality of spatial reuse fields, the resource elements through which the TB PPDU is transmitted are allocated within a secondary 160 MHz.

8. The terminal according to claim 1, in, When the TB PPDU is generated using the second plurality of spatial reuse fields, the TB PPDU is transmitted by a bandwidth indicated based on i) a bandwidth field included in the common information field and ii) an additional bandwidth field included in the trigger frame.

9. A method for transmitting data by a terminal in a wireless communication system, the method comprising: receiving a trigger frame including a common information field from an access point AP, and sending a trigger-based TB PPDU in response to the trigger frame, Wherein, when the type associated with the trigger frame is a high-efficiency HE type, the common information field includes a first plurality of spatial reuse fields used to generate the TB PPDU, and Only when the type associated with the trigger frame is an extremely high throughput (EHT) type, the trigger frame further includes a second plurality of spatial reuse fields used to generate the TB PPDU.

10. The method according to claim 9, in, When the type associated with the trigger frame is the EHT type, the TB PPDU is generated depending on the second plurality of spatial reuse fields included in the trigger frame.

11. The method according to claim 9, in, When the type associated with the trigger frame is the HE type, the TB PPDU is generated depending on the first plurality of spatial reuse fields included in the common information field.

12. The method according to claim 9, in, When the type associated with the trigger frame is the HE type, the trigger frame does not include the second plurality of spatial reuse fields.

13. The method according to claim 9, in, The trigger frame further includes identification information used to indicate whether the type related to the trigger frame is the EHT type or the HE type.

14. The method according to claim 9, in, A location of a frequency band to which a resource unit to transmit the TB PPDU is allocated varies according to whether the TB PPDU is generated using the first plurality of spatial reuse fields or the second plurality of spatial reuse fields.

15. The method according to claim 14, in, When the TB PPDU is generated using the second plurality of spatial reuse fields, the resource elements through which the TB PPDU is transmitted are allocated within a secondary 160 MHz.

16. The method according to claim 9, in, When the TB PPDU is generated using the second plurality of spatial reuse fields, the TB PPDU is transmitted by a bandwidth indicated based on i) a bandwidth field included in the common information field and ii) an additional bandwidth field included in the trigger frame.

Images