Method for transmitting and receiving data in a wireless communication system and wireless communication terminal

Abstract

To provide a high speed wireless LAN service for novel multimedia applications.SOLUTION: There is provided a method for transmitting or receiving a Physical layer Protocol Data Unit (PPDU) in a wireless communication system. A terminal receives, from an access point (AP), a frame indicating, to one or more terminals, transmission of the PPDU. The frame comprises a common information field and a user information field for each of the one or more terminals, and at least one of the common information field and the user information field is used to identify whether the PPDU indicated by a trigger frame corresponds to an extremely high throughput (EHT) PPDU or a high efficiency (HE) PPDU. In response to the frame, the terminal transmits the PPDU.SELECTED DRAWING: Figure 24

Description

[Technical Field]

[0001] The present invention relates to a wireless communication system, and more particularly to a wireless communication method and a wireless communication terminal for efficiently signaling uplink multi-user information in a wireless communication system. [Background technology]

[0002] Recently, as the popularity of mobile devices has increased, wireless LAN technology, which can provide them with high-speed wireless Internet services, has been gaining attention. Wireless LAN technology is a technology that uses short-range wireless communication technology to enable mobile devices such as smartphones, smart pads, laptop PCs, portable multimedia players, embedded devices, etc. to connect to the Internet wirelessly at home, in business, or in specific service areas.

[0003] Since supporting early wireless LAN technology using the 2.4 GHz frequency band, IEEE (Institute of Electronics Engineers) 802.11 has since implemented or is currently developing various other technology standards. IEEE 802.11b uses the 2.4 GHz frequency band and supports a maximum communication speed of 11 Mbps. IEEE 802.11a, which was commercialized after IEEE 802.11b, uses the 5 GHz frequency band instead of the 2.4 GHz band, reducing the impact of interference compared to the significantly more congested 2.4 GHz frequency band, and uses OFDM technology to improve communication speeds to a maximum of 54 Mbps. However, IEEE 802.11a has the disadvantage of a shorter communication distance than IEEE 802.11b. IEEE 802.11g, like IEEE 802.11b, uses the 2.4GHz band and achieves a maximum transmission speed of 54Mbps, and has attracted considerable attention for its backward compatibility, but it also has an advantage over IEEE 802.11a in terms of communication distance.

[0004] IEEE 802.11n is a technical standard established to overcome the communication speed limitations that have been identified as a weakness of wireless LANs. IEEE 802.11n aims to increase network speed and reliability and extend the operating distance of wireless networks. Specifically, IEEE 802.11n supports high throughput (HT) of up to 540 Mbps and is based on MIMO (Multiple Inputs and Multiple Outputs) technology, which uses multiple antennas on both the transmitting and receiving ends to minimize transmission errors and optimize data speed. This standard also uses a coding method that transmits multiple duplicate copies to increase data reliability.

[0005] As WLAN adoption continues to grow and applications become more diverse, the need for new WLAN systems is emerging to support data throughput rates (Very High Throughput, VHT) higher than those supported by IEEE 802.11n. Among these, IEEE 802.11ac supports wide bandwidth (80MHz-160MHz) in the 5GHz frequency band. While the IEEE 802.11ac standard is defined only in the 5GHz band, initial 802.11ac chipsets are expected to support operation in the 2.4GHz band as well for backward compatibility with existing 2.4GHz products. Theoretically, this standard enables multi-station WLAN speeds of at least 1Gbps and maximum single-link speeds of at least 500Mbps. This is achieved by expanding the air interface concepts adopted in 802.11n, including wider radio frequency bandwidth (up to 160MHz), more MIMO spatial streams (up to 8), multi-user MIMO, and denser modulation (up to 256QAM). Additionally, there is IEEE 802.11ad, a method of transmitting data using the 60GHz band instead of the conventional 24GHz / 5GHz. IEEE 802.11ad is a transmission standard that uses beamforming technology to provide speeds of up to 7Gbps, making it suitable for streaming large amounts of data and high-bitrate video, such as uncompressed HD video. However, the 60GHz frequency band has the disadvantage of being difficult to pass through obstacles and can only be used between devices in close proximity.

[0006] Meanwhile, the IEEE 802.11ax (High Efficiency WLAN, HEW) standard is being developed and is nearing completion as the successor to 802.11ac and 802.11ad in order to provide high-efficiency and high-performance WLAN communication technology in high-density environments where APs and terminals are densely packed. In an 802.11ax-based WLAN environment, high-frequency-efficient communication must be provided both indoors and outdoors in the presence of a high density of stations and APs (Access Points), and various technologies are being developed to achieve this.

[0007] Additionally, development of a new WLAN standard has begun to increase maximum transmission speeds to support new multimedia applications such as high-definition video and real-time gaming. IEEE 802.11be (Extremely High Throughput, EHT), the seventh generation WLAN standard, is currently being developed with the goal of supporting transmission rates of up to 30Gbps in the 2.4 / 5 / 6GHz bands through wider bandwidth, increased spatial streams, and multi-AP cooperation. Summary of the Invention [Problem to be solved by the invention]

[0008] As described above, an object of the present invention is to provide an ultra-high speed wireless LAN service for new multimedia applications.

[0009] Another object of the present invention is to provide a method and apparatus for determining the format of a physical layer protocol data unit (PPDU) based on a frame that instructs transmission of the PPDU.

[0010] Another object of the present invention is to provide a method and apparatus for setting a different value for a length field included in a PPDU depending on the format of the PPDU indicated by an AP (Access Point).

[0011] The technical problems to be solved in this specification are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those having ordinary skill in the art to which the present invention pertains from the following description. [Means for solving the problem]

[0012] In a wireless communication system, a terminal for transmitting a TB PPDU (Trigger Based Physical layer Protocol Data Unit), which is a response frame based on a trigger frame, includes a communication module and a processor that controls the communication module. The processor receives a frame from an AP (Access Point) instructing one or more terminals to transmit a Physical layer Protocol Data Unit (PPDU), the frame including a common information field and a user information field for each of the one or more terminals, at least one of the common information field and the user information field being used to identify whether the PPDU indicated by the trigger frame is an EHT (Extremely High Throughput) PPDU or an HE (High Efficiency) PPDU, and transmits the PPDU in response to the frame, the PPDU being the EHT PPDU or the HE PPDU identified by at least one of the common information field and the user information field.

[0013] In addition, in the present invention, the PPDU includes a length field related to the length of the PPDU, and the length field is set to a different value depending on whether the PPDU is the EHT PPDU or the HE PPDU.

[0014] Also, in the present invention, if the PPDU is the HE PPDU, the length field is set to the same value as the value of the length field included in the frame.

[0015] Also, in the present invention, if the PPDU is the EHT PPDU, the length field is set to a value obtained by adding a specific value to the value of the length field included in the frame.

[0016] In the present invention, the specific value is "2."

[0017] In addition, in the present invention, the specific value is used so that the value of the length field of the PPDU becomes a multiple of three when the value of the length field included in the frame is not a multiple of three.

[0018] In addition, in the present invention, the PPDU includes a PHY version identifier (ID) subfield indicating whether the PHY version of the PPDU is EHT.

[0019] In addition, in the present invention, the frame further includes a format identifier subfield, and the PHY version ID subfield is set to the same value as the format identifier subfield.

[0020] Also, in the present invention, the frame cannot indicate the transmission of both the EHT PPDU and the HE PPDU.

[0021] In addition, in the present invention, the frame further includes a triggered response scheduling (TRS) control subfield, and the PPDU is determined to be the EHT PPDU or the HE PPDU depending on the format of the frame including the TRS control subfield.

[0022] In addition, in the present invention, the common information field includes a first subfield indicating a format of a PPDU transmitted on a primary channel, and the user information field includes a second subfield indicating a location of a resource unit (RU) allocated to the terminal.

[0023] Also, in the present invention, whether the PPDU indicated by the frame is the EHT PPDU or the HE PPDU is identified based on the first subfield and the second subfield.

[0024] In addition, in the present invention, the first subfield indicates transmission of the EHT PPDU or the HE PPDU on the primary channel of the 160 MHz band, and the second subfield indicates whether the RU assigned by the user information field is located on the primary channel or a secondary channel.

[0025] The present invention also provides a method including: receiving a frame from an AP (Access Point) instructing one or more terminals to transmit a physical layer protocol data unit (PPDU), the frame including a common information field and a user information field for each of the one or more terminals, at least one of the common information field and the user information field being used to identify whether the PPDU indicated by the trigger frame is an extremely high throughput (EHT) PPDU or a high efficiency (HE) PPDU; and transmitting the PPDU in response to the frame, the PPDU being the EHT PPDU or the HE PPDU identified by at least one of the common information field and the user information field. [Effects of the Invention]

[0026] According to the embodiment of the present invention, it is possible to efficiently signal multilink information.

[0027] Furthermore, according to the embodiment of the present invention, it is possible to instruct the transmission of PPDUs of different formats using one frame.

[0028] Furthermore, according to the embodiment of the present invention, it is possible to use one frame to instruct the transmission of a legacy PPDU for backward compatibility.

[0029] Furthermore, according to the embodiment of the present invention, it is possible to increase the overall resource utilization rate in a contention-based channel access system and improve the performance of a WLAN system.

[0030] The effects obtained from the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those having ordinary skill in the art to which the present invention pertains from the following description. [Brief explanation of the drawings]

[0031] [Figure 1] 1 is a diagram showing a wireless LAN system according to an embodiment of the present invention. [Figure 2] FIG. 10 is a diagram showing a wireless LAN system according to another embodiment of the present invention. [Figure 3] FIG. 2 is a diagram showing the configuration of a station according to an embodiment of the present invention. [Figure 4] FIG. 2 is a diagram illustrating a configuration of an access point according to an embodiment of the present invention. [Figure 5] 1 is a diagram illustrating a process in which a STA establishes a link with an AP. [Figure 6] FIG. 1 is a diagram illustrating a CSMA (Carrier Sense Multiple Access) / CA (Collision Avoidance) method used in wireless LAN communication. [Figure 7] 1 shows examples of various standard generation PPDU (PLCP Protocol Data Unit) formats. [Figure 8]1 illustrates various Extremely High Throughput (EHT) Physical Protocol Data Unit (PPDU) formats and methods for indicating the same according to an embodiment of the present invention. [Figure 9] 1 is a diagram illustrating a multi-link device according to an embodiment of the present invention. [Figure 10] 1 illustrates a wireless LAN function according to an embodiment of the present invention. [Figure 11] 1 illustrates an uplink (UL) multi-user (MU) operation according to one embodiment of the present invention. [Figure 12] 1 shows a trigger frame format according to one embodiment of the present invention. [Figure 13] 10 illustrates a UL MU operation according to yet another embodiment of the present invention. [Figure 14] 10 illustrates a UL MU operation according to yet another embodiment of the present invention. [Figure 15] 1 illustrates a method for indicating a trigger-based PPDU format according to an embodiment of the present invention. [Figure 16] 1 shows a trigger frame format for indicating a trigger-based PPDU format according to one embodiment of the present invention. [Figure 17] 10 illustrates a trigger frame format for indicating a trigger-based PPDU format according to yet another embodiment of the present invention. [Figure 18] 10 illustrates a method for determining a trigger frame format according to one embodiment of the present invention. [Figure 19] 10 illustrates a method for setting a length field according to an embodiment of the present invention. [Figure 20] 10 illustrates a UL MU operation according to yet another embodiment of the present invention. [Figure 21] 10 illustrates a UL MU operation according to yet another embodiment of the present invention. [Figure 22]1 illustrates UL Orthogonal Frequency Division Multiple Access (OFDMA)-based random access (UORA) operation according to one embodiment of the present invention. [Figure 23] 10 illustrates a UL MU operation according to yet another embodiment of the present invention. [Figure 24] 1 is a flowchart illustrating an example of a PPDU transmission method according to an embodiment of the present invention. [Figure 25] 10 is a flowchart illustrating an example of a method for transmitting a frame for instructing transmission of a PPDU according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0032] The terms used in this specification are generally used as widely as possible, taking into consideration the functions of the present invention. However, these may vary depending on the intentions of engineers in the relevant technical field, customs, or the emergence of new technologies. In addition, in certain cases, the applicant may have arbitrarily selected terms, and in such cases, the meanings thereof will be described in the relevant description of the invention. Therefore, it is made clear that the terms used in this specification should be interpreted not simply as names of terms, but based on the substantive meanings of the terms and the overall content of this specification.

[0033] Throughout this specification, when a component is referred to as being "connected" to another component, this includes not only when the component is "directly connected" to the other component, but also when the component is "electrically connected" to the other component via another component therebetween. Furthermore, when a component is referred to as "comprising" a specific component, this does not mean that the component excludes the other component, but that the component may further include the other component, unless otherwise specified. Additionally, limitations such as "greater than" or "less than" based on a specific critical value may be appropriately substituted with "exceeds" or "less than," respectively, depending on the embodiment. Hereinafter, in the present invention, the terms "field" and "subfield" may be used interchangeably.

[0034] FIG. 1 is a diagram showing a wireless LAN system according to an embodiment of the present invention.

[0035] A wireless LAN system includes one or more Basic Service Sets (BSSs), which are a set of devices that can synchronize and communicate with each other. Generally, BSSs are classified into infrastructure BSSs and independent BSSs (IBSSs), and Figure 1 shows an infrastructure BSS.

[0036] As shown in FIG. 1, infrastructure BSSs BSS1 and BSS2 include one or more stations STA1, STA2, STA3, STA4, and STA5, access points AP-1 and AP-2 that are stations providing distribution services, and a distribution system DS that connects multiple access points AP-1 and AP-2.

[0037] A station (STA) is any device that includes a medium access control (MAC) and a physical layer interface for a wireless medium according to the IEEE 802.11 standard. In a broad sense, the term "station" encompasses not only non-AP stations but also APs. In this specification, the term "terminal" refers to either a non-AP or an AP, or both. A station for wireless communication includes a processor and a communication unit, and may further include a user interface and a display unit, depending on the embodiment. The processor generates frames to be transmitted over a wireless network, processes frames received over the wireless network, and performs various other processes for controlling the station. The communication unit is functionally connected to the processor and transmits and receives frames over the wireless network for the station. In this specification, the term "terminal" encompasses user equipment (UE).

[0038] An access point (AP) is an entity that provides a connection to a distribution system (DS) via a wireless medium for associated stations. In an infrastructure BSS, communication between non-AP stations is generally performed via the AP. However, if a direct link is established, direct communication is also possible between non-AP stations. Meanwhile, in the present invention, the term AP is used as a concept including a personal BSS coordination point (PCP), but in a broader sense, it also includes concepts such as a central controller, a base station (BS), a node B, a base transceiver system (BTS), or a site controller. In the present invention, an AP is also referred to as a base wireless communication terminal, but in a broader sense, the term base wireless communication terminal is used as a term including an AP, a base station, an eNodeB (eNB), and a transmission point (TP). In addition, the base wireless communication terminal includes various types of wireless communication terminals that allocate communication medium resources and perform scheduling for communication with multiple wireless communication terminals.

[0039] A plurality of infrastructure BSSs are connected to each other via a distribution system DS, and the plurality of BSSs connected via the distribution system are called an Extended Service Set (ESS).

[0040] 2 is a diagram showing an independent BSS, which is a wireless LAN system according to another embodiment of the present invention. In the embodiment of FIG. 2, the same or corresponding parts as those in the embodiment of FIG. 1 will not be described again.

[0041] BSS3 shown in Figure 2 is an independent BSS and does not include an AP, so none of the stations (STA6, STA7) are connected to an AP. An independent BSS is not allowed to connect to a distribution system and forms a self-contained network. In an independent BSS, each station (STA6, STA7) is directly connected to each other.

[0042] 3 is a block diagram showing the configuration of a station 100 according to an embodiment of the present invention. As shown, the station 100 according to the embodiment of the present invention includes a processor 110, a communication unit 120, a user interface unit 140, a display unit 150, and a memory 160.

[0043] First, the communication unit 120 transmits and receives wireless signals such as WLAN packets and may be incorporated into or external to the station 100. 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 using different frequency bands such as 2.4 GHz, 5 GHz, 6 GHz, and 60 GHz. According to an embodiment, the station 100 may include a communication module using a frequency band above 7.125 GHz and a communication module using a frequency band below 7.125 GHz. Each communication module may perform wireless communication with an AP or an external station based on the WLAN standard of the frequency band supported by the communication module. The communication unit 120 may operate only one communication module at a time or multiple communication modules simultaneously, depending on the performance and requirements of the station 100. When the station 100 includes multiple communication modules, each communication module may be provided independently, or multiple modules may be integrated into a single chip. In the embodiment of the present invention, the communication unit 120 may represent a radio frequency (RF) communication module that processes RF signals.

[0044] Next, the user interface 140 includes various types of input / output means provided in the station 100. That is, the user interface unit 140 receives user input using various input means, and the processor 110 controls the station 100 based on the received user input. Also, the user interface unit 140 performs output based on instructions from the processor 110 using various output means.

[0045] Next, the display unit 150 outputs an image on a display screen. The display unit 150 outputs various display objects, such as a user interface, based on the contents processed by the processor 110 or the control commands of the processor 110. The memory 160 also stores control programs and various data used by the station 100. The control programs include a connection program required for the station 100 to connect to an AP or an external station.

[0046] The processor 110 of the present invention executes various commands or programs to process data within the station 100. The processor 110 also controls each unit of the station 100 and controls the transmission and reception of data between the units. According to an embodiment of the present invention, the processor 110 executes a program for connection with an AP stored in the memory 160 and receives a communication setup message transmitted by the AP. The processor 110 also reads information about the station 100's preferences contained in the communication setup message and requests connection to the AP based on the information about the station 100's preferences. The processor 110 of the present invention may refer to a main control unit of the station 100, or, depending on the embodiment, may refer to a control unit for individually controlling some components of the station 100, such as the communication unit 120. That is, the processor 110 may be a modem that modulates and demodulates wireless signals transmitted and received by the communication unit 120, or a modulator and / or demodulator. The processor 110 controls various operations for transmitting and receiving wireless signals in the station 100 according to an embodiment of the present invention. A detailed embodiment of this will be described later.

[0047] The station 100 shown in FIG. 3 is a block diagram according to an embodiment of the present invention, and the separate blocks indicate the logically separated elements of the device. Therefore, the above-described device elements may be mounted on a single chip or multiple chips depending on the device design. For example, the processor 110 and the communication unit 120 may be integrated into a single chip or may be mounted on separate chips. Furthermore, in embodiments of the present invention, some components of the station 100, such as the user interface unit 140 and the display unit 150, may be selectively provided in the station 100.

[0048] 4 is a block diagram showing the configuration of an AP 200 according to an embodiment of the present invention. As shown, the AP 200 according to the embodiment of the present invention includes a processor 210, a communication unit 220, and a memory 260. In FIG. 4, duplicated descriptions of parts of the configuration of the AP 200 that are the same as or correspond to the configuration of the station 100 in FIG. 3 will be omitted.

[0049] Referring to FIG. 4, the AP 200 according to the present invention includes a communication unit 220 for operating a BSS in at least one frequency band. As described above in the embodiment of FIG. 3, the communication unit 220 of the AP 200 may also include multiple 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 using different frequency bands, for example, 2.4 GHz, 5 GHz, 6 GHz, and 60 GHz. Preferably, the AP 200 may include a communication module using a frequency band above 7.125 GHz and a communication module using a frequency band below 7.125 GHz. Each communication module may perform wireless communication with a station based on the WLAN standard of the frequency band supported by the communication module. The communication unit 220 may operate only one communication module at a time or multiple communication modules simultaneously, depending on the performance and requirements of the AP 200. In the embodiment of the present invention, the communication unit 220 may represent an RF (Radio Frequency) communication module that processes RF signals.

[0050] The memory 260 stores control programs used by the AP 200 and various data associated therewith. These control programs include a connection program that manages station connections. The processor 210 also controls each unit of the AP 200 and controls data transmission and reception between the units. According to an embodiment of the present invention, the processor 210 executes a program for connecting with a station stored in the memory 260 and transmits a communication setup message to one or more stations. The communication setup message includes information regarding connection preferences for each station. The processor 210 also performs connection setup in response to a station connection request. According to an embodiment, the processor 210 is a modem or a modulator / demodulator that modulates and demodulates wireless signals transmitted and received by the communication unit 220. The processor 210 controls various operations for transmitting and receiving wireless signals by the AP 200 according to an embodiment of the present invention. A detailed embodiment of this will be described later.

[0051] FIG. 5 is a diagram illustrating a process in which a STA establishes a link with an AP.

[0052] 5, a link between the STA 100 and the AP 200 is established through three steps: scanning, authentication, and association. First, the scanning step is a step in which the STA 100 acquires connection information for the BSS operated by the AP 200. There are two scanning methods: a passive scanning method in which the STA 100 acquires information using only a beacon message S101 periodically transmitted by the AP 200, and an active scanning method in which the STA 100 transmits a probe request to the AP S103, receives a probe response from the AP S105, and acquires connection information.

[0053] The STA 100 that successfully receives wireless connection information in the scanning step transmits an authentication request (S107a), receives an authentication response from the AP 200, and performs the authentication step (S107b). After the authentication step is performed, the STA 100 transmits an association request (S109a), receives an association response from the AP 200, and performs the association step (S109b). In this specification, association basically means wireless association, but the present invention is not limited to this, and association in a broad sense includes both wireless association and wired association.

[0054] Meanwhile, an 802.1X-based authentication step S111 and an IP address acquisition step S113 via DHCP are additionally performed. In Fig. 5, server 300 is a server that processes 802.1X-based authentication with STA 100, and may be physically connected to AP 200 or may exist as a separate server.

[0055] FIG. 6 is a diagram showing a CSMA (Carrier Sense Multiple Access) / CA (Collision Avoidance) method used in wireless LAN communication.

[0056] A terminal performing WLAN communication performs carrier sensing to check whether a channel is occupied before transmitting data. If a wireless signal above a certain strength is detected, the channel is determined to be occupied, and the terminal delays access to the channel. This process is called Clear Channel Assessment (CCA), and the level that determines whether or not a signal is detected is called the CCA threshold. If a wireless signal above the CCA threshold is received by the terminal and the terminal is the receiver, the terminal processes the received wireless signal. On the other hand, if no wireless signal is detected from the channel or a wireless signal with a strength below the CCA threshold is detected, the channel is determined to be idle.

[0057] If the channel is determined to be idle, each terminal with data to transmit performs a backoff procedure after an IFS (Inter Frame Space), such as an AIFS (Arbitration IFS) or a PIFS (PCF IFS), depending on the status of each terminal. In some embodiments, the AIFS is used as a configuration replacing the conventional DIFS (DCF IFS). Each terminal waits while decreasing a slot time by a random number determined for the corresponding terminal during the idle interval of the channel, and a terminal that has exhausted all slot times attempts to access the corresponding channel. The period during which each terminal performs the backoff procedure is called a contention window period.

[0058] If a specific terminal successfully accesses the channel, it transmits data over the channel. However, if the terminal attempting access collides with another terminal, the colliding terminals are assigned new random numbers and perform a backoff procedure again. According to one embodiment, the new random numbers assigned to each terminal are determined within a range (2*CW) twice the range of the random numbers previously assigned to the terminal (contention window, CW). Meanwhile, each terminal attempts access by performing a backoff procedure again in the next contention window period. At this time, each terminal performs the backoff procedure from the slot time remaining in the previous contention window period. In this way, terminals communicating over a wireless LAN can avoid collisions with each other on a specific channel.

[0059] Hereinafter, in the present invention, a terminal may be referred to as a non-AP STA, an AP STA, an AP, an STA, a receiving device, or a transmitting device, and the present invention is not limited thereto. Also, in the present invention, an AP STA may be referred to as an AP.

[0060] <Examples of various PPDU formats>

[0061] Figure 7 shows examples of various standard generation PPDU (PLCP Protocol Data Unit) formats. More specifically, Figure 7(a) shows an example of a legacy PPDU format based on 802.11a / g, Figure 7(b) shows an example of an HE PPDU format based on 802.11ax, and Figure 7(c) shows an example of a non-legacy PPDU (i.e., EHT PPDU) format based on 802.11be. Also, Figure 7(d) shows detailed field configurations of L-SIG and RL-SIG commonly used in the PPDU formats.

[0062] 7(a), the preamble of the legacy PPDU includes a Legacy Short Training field (L-STF), a Legacy Long Training field (L-LTF), and a Legacy Signal field (L-SIG). In an embodiment of the present invention, the L-STF, L-LTF, and L-SIG may be referred to as a legacy preamble.

[0063] Referring to FIG. 7(b), the preamble of the HE PPDU further includes a Repeated Legacy Short Training field (RL-SIG), a High Efficiency Signal A field (HE-SIG-A), a High Efficiency Signal B field (HE-SIG-B), a High Efficiency Short Training field (HE-STF), and a High Efficiency Long Training field (HE-LTF) in addition to the legacy preamble. In an embodiment of the present invention, the RL-SIG, HE-SIG-A, HE-SIG-B, HE-STF, and HE-LTF can be referred to as an HE preamble. The specific configuration of the HE preamble may vary depending on the HE PPDU format. For example, HE-SIG-B may be used only in the HE MU PPDU format.

[0064] Referring to FIG. 7(c), the preamble of the EHT PPDU further includes a Repeated Legacy Short Training field (RL-SIG), a Universal Signal field (U-SIG), an Extremely High Throughput Signal A field (EHT-SIG-A), an Extremely High Throughput Signal B field (EHT-SIG-A), an Extremely High Throughput Short Training field (EHT-STF), and an Extremely High Throughput Long Training field (EHT-LTF) in addition to the legacy preamble. In an embodiment of the present invention, the RL-SIG, EHT-SIG-A, EHT-SIG-B, EHT-STF, and EHT-LTF may be referred to as an EHT preamble. The specific configuration of the non-legacy preamble may vary depending on the EHT PPDU format. For example, EHT-SIG-A and EHT-SIG-B may be used only in some EHT PPDU formats.

[0065] The L-SIG field included in the PPDU preamble is configured with a total of 64 subcarriers using 64 FFT OFDM. Of these, 48 subcarriers, excluding guard subcarriers, DC subcarriers, and pilot subcarriers, are used for L-SIG data transmission. BPSK and Rate=1 / 2 MCS (Modulation and Coding Scheme) are applied to the L-SIG, so it can contain a total of 24 bits of information. Figure 7(d) shows the 24-bit information structure of the L-SIG.

[0066] Referring to FIG. 7(d), the L-SIG includes an L_RATE field and an L_LENGTH field. The L_RATE field is composed of 4 bits and indicates the MCS used for data transmission. Specifically, the L_RATE field indicates one of the transmission rates of 6, 9, 12, 18, 24, 36, 48, or 54 Mbps, which is a combination of a modulation scheme such as BPSK, QPSK, 16-QAM, or 64-QAM and a code rate such as 1 / 2, 2 / 3, or 3 / 4. The combined information in the L_RATE and L_LENGTH fields indicates the total length of the PPDU. In a non-legacy PPDU format, the L_RATE field is set to the minimum rate of 6 Mbps.

[0067] The unit of the L_LENGTH field is a byte, and a total of 12 bits are allocated, allowing a maximum of 4095 to be signaled. In combination with the L_RATE field, it can indicate the length of the corresponding PPDU. In this case, legacy and non-legacy terminals can interpret the L_LENGTH field in different ways.

[0068] First, a legacy or non-legacy terminal interprets the length of the corresponding PPDU using the L_LENGTH field as follows. When the value of the L_RATE field is set to indicate 6 Mbps, 3 bytes (i.e., 24 bits) may be transmitted during 4 us, which is one symbol duration of the 64FFT. Therefore, by adding the 3 bytes corresponding to the SVC field and Tail field to the L_LENGTH field value and dividing this by 3 bytes, which is the transmission amount of one symbol, the number of 64FFT reference symbols after the L-SIG is obtained. The obtained number of symbols is multiplied by 4 us, which is one symbol duration, and then 20 us, which is required to transmit the L-STF, L-LTF, and L-SIG, to obtain the length of the corresponding PPDU, i.e., the reception time (RXTIME). This can be expressed mathematically as shown in Equation 1 below.

[0069]

number

[0070] At this time,

number

[0071] represents the smallest natural number greater than or equal to x. Since the maximum value of the L_LENGTH field is 4095, the length of the PPDU may be set to a maximum of 5.484 ms. A non-legacy terminal transmitting the PPDU must set the L_LENGTH field as shown in Equation 2 below.

[0072]

number

[0073] Here, TXTIME is the total transmission time constituting the PPDU, and is expressed as the following equation 3. In this case, TX represents the transmission time of X.

[0074]

number

[0075] Referring to the above formula, the length of the PPDU is calculated based on the rounded up value of L_LENGTH / 3. Therefore, for any value of k, three different values ​​of L_LENGTH={3k+1, 3k+2, 3(k+1)} indicate the same PPDU length.

[0076] Referring to Figure 7(e), the U-SIG (Universal SIG) field remains in the EHT PPDU and subsequent generation WLAN PPDUs, and serves to distinguish which generation of PPDU it is, including 11be. The U-SIG is two 64FFT-based OFDM symbols and can transmit a total of 52 bits of information. Of these, 43 bits excluding 9 bits of CRC / tail are roughly divided into a VI (Version Independent) field and a VD (Version Dependent) field.

[0077] The VI bit will maintain its current bit configuration, so even if a subsequent generation PPDU is defined, current 11be UEs can obtain information about the PPDU from the VI field of the PPDU. To this end, the VI field consists of the PHY version, UL / DL, BSS color, TXOP, and Reserved fields. The PHY version field is 3 bits long and serves to sequentially distinguish between 11be and subsequent generations of WLAN standards. 11be has a value of 000b. The UL / DL field identifies whether the PPDU is an uplink or downlink PPDU. The BSS color represents a BSS identifier defined in 11ax and has a value of 6 or more bits. The TXOP represents the transmit opportunity duration (Transmit Opportunity Duration) transmitted in the MAC header. By adding it to the PHY header, the length of the TXOP containing the PPDU can be inferred without decoding the MPDU, and has a value of 7 or more bits.

[0078] The VD field, which is signaling information useful only for 11be version PPDUs, may consist of fields commonly used in any PPDU format, such as the PPDU format and BW, as well as fields defined differently for each PPDU format. The PPDU format is a separator that distinguishes between EHT SU (Single User), EHT MU (Multiple User), EHT TB (Trigger-based), and EHT ER (Extended Range) PPDUs. The BW field broadly signals five basic PPDU BW options: 20, 40, 80, 160 (80 + 80), and 320 (160 + 160) MHz (BWs that can be expressed in the form of a power of 20 * 2 can be called basic BWs), as well as various remaining PPDU BWs formed by preamble puncturing. After signaling at 320 MHz, a portion of 80 MHz may be punctured. In addition, the punctured and modified channel shape may be signaled directly in the BW field, or may be signaled using both the BW field and a field that appears after the BW field (for example, a field in the EHT-SIG field). If the BW field is 3 bits, a total of 8 BW signalings are possible, so a maximum of 3 puncturing modes can be signaled. If the BW field is 4 bits, a total of 16 BW signalings are possible, so a maximum of 11 puncturing modes can be signaled.

[0079] The fields located after the BW field vary depending on the type and format of the PPDU. MU PPDUs and SU PPDUs may be signaled in the same PPDU format, and a field for distinguishing between MU PPDUs and SU PPDUs may be located before the EHT-SIG field, and additional signaling may be performed for this purpose. Both SU PPDUs and MU PPDUs include an EHT-SIG field, but some fields not required for the SU PPDU may be compressed. In this case, the information of the compressed fields may be omitted or may have a reduced size compared to the size of the original fields included in the MU PPDU. For example, the SU PPDU may have a different configuration, such as the common fields of the EHT-SIG being omitted or replaced, or the user-specific fields being replaced or reduced to one.

[0080] Alternatively, the SU PPDU may further include a compression field indicating whether or not it is compressed, and some fields (such as the RA field) may be omitted depending on the value of the compression field.

[0081] When a portion of the EHT-SIG field of the SU PPDU is compressed, the information included in the compressed field may be signaled together in an uncompressed field (e.g., a common field). In the case of an MU PPDU, since it is a PPDU format for simultaneous reception by multiple users, the EHT-SIG field must be transmitted after the U-SIG field, and the amount of information signaled may be variable. That is, since multiple MU PPDUs are transmitted to multiple STAs, each STA must recognize the location of the RU to which the MU PPDU is transmitted, the STA to which each RU is assigned, and whether the transmitted MU PPDU was sent to it. Therefore, the AP must transmit the above information in the EHT-SIG field. To this end, the U-SIG field signals information for efficiently transmitting the EHT-SIG field, which may be the number of symbols in the EHT-SIG field and / or the MCS, which is the modulation method. The EHT-SIG field may include information on the size and location of the RU assigned to each user.

[0082] In the case of an SU PPDU, a STA may be assigned multiple RUs, and the multiple RUs may be contiguous or discontinuous. If the RUs assigned to the STA are not contiguous, the STA can efficiently receive the SU PPDU only by recognizing punctured RUs in between. Therefore, the AP can transmit the SU PPDU including information on punctured RUs among the RUs assigned to the STA (e.g., puncturing pattern of the RUs). That is, in the case of an SU PPDU, a puncturing mode field including information indicating whether a puncturing mode is applied and the puncturing pattern in a bitmap format, etc., may be included in the EHT-SIG field, and the puncturing mode field can signal the type of discontinuous channels appearing within the bandwidth.

[0083] The type of signaled discontinuous channel is limited, and indicates the BW and discontinuous channel information of the SU PPDU in combination with the value of the BW field. For example, since the SU PPDU is a PPDU transmitted only to a single UE, the STA can recognize its allocated bandwidth from the BW field included in the PPDU and can recognize punctured resources within the allocated bandwidth from the puncturing mode field of the U-SIG field or EHT-SIG field included in the PPDU. In this case, the UE can receive the PPDU in the remaining resource units excluding specific channels of the punctured resource units. In this case, multiple RUs allocated to the STA may be configured with different frequency bands or tones.

[0084] The reason why only limited discontinuous channel types are signaled is to reduce the signaling overhead of the SU PPDU. Since puncturing can be performed for each 20 MHz subchannel, if puncturing is performed on a BW having multiple 20 MHz subchannels, such as 80, 160, or 320 MHz, in the case of 320 MHz, the discontinuous channel type (when only the end 20 MHz is punctured and considered discontinuous) must be signaled by expressing whether or not each of the remaining 15 20 MHz subchannels excluding the primary channel is in use. Using 15 bits to signal the discontinuous channel type for single-user transmission can result in excessive signaling overhead when considering the low transmission rate of the signaling part.

[0085] This invention proposes a method for signaling the discontinuous channel type of the SU PPDU, shows the discontinuous channel type determined by the proposed method, and proposes a method for signaling the primary 160 MHz and secondary 160 MHz puncturing types in the 320 MHz BW configuration of the SU PPDU.

[0086] In addition, one embodiment of the present invention proposes a method of varying the PPDU configuration indicated by the preamble puncturing BW value according to the PPDU format signaled in the PPDU format field. Assuming that the length of the BW field is 4 bits, in the case of an EHT SU PPDU or TB PPDU, an EHT-SIG-A symbol of one symbol may be further signaled after the U-SIG, or no EHT-SIG-A may be signaled at all. Taking this into consideration, up to 11 puncturing modes must be signaled using only the BW field of the U-SIG. However, in the case of an EHT MU PPDU, an EHT-SIG-B symbol is further signaled after the U-SIG, so up to 11 puncturing modes may be signaled in a different manner than in the SU PPDU. In the case of an EHT ER PPDU, the BW field can be set to 1 bit to signal whether the PPDU uses a 20 MHz or 10 MHz bandwidth.

[0087] Figure 7(f) shows the format-specific field configuration of the VD field when the PPDU format field of the U-SIG indicates an EHT MU PPDU. For an MU PPDU, SIG-B, a signaling field for simultaneous reception by multiple users, is required. SIG-B may be transmitted after the U-SIG without a separate SIG-A. For this purpose, the U-SIG must signal information for decoding the SIG-B. These fields include the SIG-B MCS, SIG-B DCM, number of SIG-B symbols, SIG-B compression, and number of EHT-LTF symbols.

[0088] FIG. 8 illustrates an example of various Extremely High Throughput (EHT) Physical Protocol Data Unit (PPDU) formats and methods for indicating the same according to an embodiment of the present invention.

[0089] 8, a PPDU may be configured with a preamble and a data portion, and the format of one type, EHT PPDU, may be distinguished by a U-SIG field included in the preamble. Specifically, whether the format of the PPDU is EHT PPDU may be indicated based on a PPDU format field included in the U-SIG field.

[0090] 8(a) shows an example of an EHT SU PPDU format for a single STA. The EHT SU PPDU is a PPDU used for single user (SU) transmission between an AP and a single STA, and an EHT-SIG-A field for additional signaling may be located after the U-SIG field.

[0091] 8(b) shows an example of an EHT trigger-based PPDU format, which is an EHT PPDU transmitted based on a trigger frame. The EHT trigger-based PPDU is an EHT PPDU transmitted based on a trigger frame and is an uplink PPDU used for responding to the trigger frame. Unlike the EHT SU PPDU, the EHT PPDU does not have an EHT-SIG-A field after the U-SIG field.

[0092] 8(c) shows an example of an EHT MU PPDU format, which is an EHT PPDU for multiple users. The EHT MU PPDU is a PPDU used to transmit a PPDU to one or more STAs. In the EHT MU PPDU format, an HE-SIG-B field may be located after the U-SIG field.

[0093] 8(d) shows an example of an EHT ER SU PPDU format used for single-user transmission with STAs in an extended range. The EHT ER SU PPDU may be used for single-user transmission with STAs in a wider range than the EHT SU PPDU described in FIG. 8(a), and the U-SIG field may be repeated on the time axis.

[0094] The EHT MU PPDU described in (c) of Figure 8 can be used by the AP for downlink transmission to multiple STAs. In this case, the EHT MU PPDU can include scheduling information so that multiple STAs can simultaneously receive the PPDU transmitted from the AP. The EHT MU PPDU can convey AID information of the receiver and / or sender of the transmitted PPDU to the STA through the user specific field of the EHT-SIG-B. Therefore, multiple terminals receiving the EHT MU PPDU can perform spatial reuse based on the AID information of the user specific field included in the preamble of the received PPDU.

[0095] Specifically, the resource unit allocation (RA) field of the HE-SIG-B field included in the HE MU PPDU may include information regarding the configuration of resource units (e.g., the division type of resource units) in a specific bandwidth (e.g., 20 MHz) on the frequency axis. That is, the RA field may indicate the configuration of resource units divided by the bandwidth for transmitting the HE MU PPDU so that the STA can receive the PPDU. Information about the STA allocated (or designated) to each divided resource unit may be included in a user specific field of the EHT-SIG-B and transmitted to the STA. That is, the user specific field may include one or more user fields corresponding to each divided resource unit.

[0096] For example, among the multiple divided resource units, the user field corresponding to at least one resource unit used for data transmission may include the AID of the receiver or sender, and the user field corresponding to the remaining resource units not used for data transmission may include a previously set null STA ID.

[0097] Two or more PPDUs shown in FIG. 8 can be indicated by a value indicating the same PPDU format. That is, two or more PPDUs can be indicated as the same PPDU format by the same value. For example, an EHT SU PPDU and an EHT MU PPDU can be indicated by the same value using the U-SIG PPDU format subfield. In this case, the EHT SU PPDU and the EHT MU PPDU can be distinguished depending on the number of STAs receiving the PPDU. For example, a PPDU received by only one STA may be identified as an EHT SU PPDU, and when the number of STAs is set so that two or more STAs can receive the PPDU, it may be identified as an EHT MU PPDU. In other words, two or more PPDU formats shown in FIG. 8 can be indicated using the same subfield value.

[0098] In addition, some of the fields or some information of the fields shown in Figure 8 may be omitted, and such a case where some of the fields or some information of the fields is omitted can be defined as a compression mode or a compressed mode.

[0099] FIG. 9 is a diagram illustrating a multi-link device according to an embodiment of the present invention.

[0100] Referring to FIG. 9, the concept of a device to which one or more STAs are affiliated may be defined. As another example, according to an embodiment of the present invention, a device to which more than one STA is affiliated (i.e., two or more) may be defined. In this case, the device may be a logical concept. Therefore, such a device to which one or more STAs are affiliated may be referred to as a multi-link device (MLD), a multi-band device, or a multi-link logical entity (MLLE).

[0101] Alternatively, the above conceptual device can be called a multi-link entity (MLE). Also, the MLD may have one MAC medium access control service access point (SAP) to the logical link control (LLC), and the MLD may have one MAC data service.

[0102] A STA included in an MLD can operate on one or more links or channels. That is, a STA included in an MLD can operate on multiple different channels. For example, a STA included in an MLD can operate using channels in different frequency bands, such as 2.4 GHz, 5 GHz, and 6 GHz. This allows MLD to obtain gains in channel access and improve overall network performance. While existing WLANs operate on a single link, MLD operation can use multiple links to obtain more channel access opportunities or allow STAs to operate efficiently on multiple links taking into account channel conditions.

[0103] Also, if the STA affiliated to the MLD is an AP, the MLD to which the AP is affiliated may be an AP MLD, whereas if the STA affiliated to the MLD is a non-AP STA, the MLD to which the non-AP is affiliated may be a non-AP MLD.

[0104] 9, an MLD including multiple STAs may exist, and the multiple STAs included in the MLD may operate on multiple links. In FIG. 9, an MLD including APs AP1, AP2, and AP3 may be referred to as an AP MLD, and an MLD including non-AP STAs non-AP STA1, non-AP STA2, and non-AP STA3 may be referred to as a non-AP MLD. STAs included in the MLD may operate on Link 1, Link 2, Link 3, or some of Links 1 to 3.

[0105] According to an embodiment of the present invention, the multi-link operation may include a multi-link setup operation. The multi-link setup operation may be an operation corresponding to the association performed in the single-link operation. To exchange frames over the multiple links, the multi-link setup may be preceded by the multi-link setup. The multi-link setup operation may be performed using a multi-link setup element. Here, the multi-link setup element may include capability information related to the multiple links. The capability information may include information related to whether a STA included in the MLD can receive a frame over one link while another STA included in the MLD can transmit a frame over another link. That is, the capability information may include information related to whether a STA (non-AP STA and / or AP (or AP STA)) can simultaneously transmit / receive frames in different transmission directions over the links included in the MLD. The capability information may also include information related to available links or operating channels. The multi-link setup may be set up through negotiation between peer STAs, and the multi-link operation may be set up over one link.

[0106] According to one embodiment of the present invention, a mapping relationship may exist between a TID and a link of an MLD. For example, when a TID and a link are mapped, the TID may be transmitted on the mapped link. The mapping between a TID and a link may be directional-based. For example, a mapping may be performed for each of the two directions between MLD1 and MLD2. Furthermore, a default setting may exist for the mapping between a TID and a link. For example, the mapping between a TID and a link may basically be such that all TIDs are mapped to a certain link.

[0107] FIG. 10 shows a wireless LAN function according to an embodiment of the present invention.

[0108] Referring to FIG. 10 , a WLAN of a certain standard may include the functions of a WLAN of another standard. Or, when a WLAN of a certain standard is used, it may be a WLAN of another standard. Here, WLAN may refer to an STA. Furthermore, WLAN may refer to an MLD including an STA. For example, a WLAN standard may include the standard functions of a previous generation and additional functions. For example, an HT STA may be an OFDM PHY STA. An HT STA may also perform additional functions in addition to the functions of an OFDM PHY STA. For example, a VHT STA may be an HT STA. A VHT STA may also perform additional functions in addition to the functions of an HT STA. For example, an HE STA may be a VHT STA. An HE STA may also perform additional functions in addition to the functions of a VHT STA. An EHT STA may be an HE STA. An EHT STA may also perform additional functions in addition to the functions of an HE STA. There may also be standards subsequent to the EHT standard. In the present invention, the standard subsequent to the EHT standard can be called the NEXT standard, and the STA that complies with the NEXT standard can be called the NEXT STA. The NEXT STA may be an EHT STA. In addition, the NEXT STA can perform additional functions in addition to the functions of the EHT STA.

[0109] Figure 10 is a diagram showing the relationship between STAs of each standard. Referring to Figure 10, an EHT STA can be an HE STA, a VHT STA, an HT STA, or an OFDM PHY STA. Also, a NEXT STA can be an EHT STA, an HE STA, a VHT STA, an HT STA, or an OFDM PHY STA.

[0110] FIG. 11 illustrates an uplink (UL) multi-user (MU) operation according to one embodiment of the present invention.

[0111] Referring to FIG. 11, an AP can instruct at least one STA to transmit a PPDU using a specific frame (e.g., a triggering frame), and at least one STA can simultaneously transmit PPDUs of the same or different formats based on the specific frame transmitted from the AP.

[0112] Specifically, as shown in FIG. 11, a frame soliciting or triggering a multi-user (MU) transmission may be transmitted, and one or more STAs may transmit or respond to such a frame based on the frame. In this case, when one or more STAs transmit a response to the frame, the one or more STAs may simultaneously respond immediately based on the frame, and the response to the frame may begin transmission SIFS after the end of the PPDU including the frame. For example, if the frame solicits an immediate response, one or more STAs may immediately transmit a response to the frame. A frame soliciting or triggering one or more STAs to transmit may be a trigger frame or a frame including information in its MAC header that solicits or triggers uplink transmission to one or more STAs. In this case, the frame may include information (e.g., a TRS control subfield) in its MAC header that triggers or instructs only one STA to transmit uplink.

[0113] For example, the information indicating or triggering an uplink transmission included in the MAC header may be a triggered response scheduling (TRS) or TRS control subfield included in an HT control field, a control subfield, or an A-control subfield.

[0114] A frame for instructing or triggering uplink transmission may be transmitted by an AP. If the frame for instructing or triggering uplink transmission is a trigger frame, a response thereto may be transmitted in a trigger-based PPDU (TB PPDU) format. In this case, the TB PPDU may include the above-mentioned HE TB PPDU and EHT TB PPDU, as well as a NEXT TB PPDU that may be defined in a future standard.

[0115] The HE TB PPDU may consist of a preamble, data, and a packet extension (PE), and the preamble may include an L-STF, an L-LTF, an L-SIG, an RL-SIG, an HE-SIG-A, an HE-STF, and an HE-LTF in that order.

[0116] The EHT TB PPDU and NEXT TB PPDU may also be composed of a preamble, data, and PE, and the preambles of the EHT TB PPDU and NEXT TB PPDU may include L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, (EHT- / NEXT-)STF, and (EHT- / NEXT-)LTF in sequence.

[0117] A frame that instructs or triggers one or more STAs to transmit a PPDU may include information required for one or more STAs to transmit a TB PPDU. For example, if a frame includes a type subfield of "01" (B3 B2) and a subtype subfield of "0010" (B7 B6 B5 B4), the frame including such type and subtype subfields may be a trigger frame, which is a control frame.

[0118] If multiple STAs are instructed or triggered to respond with a TB PPDU, and the formats of the PPDUs to which the multiple STAs respond are different, the AP that instructed or triggered the response may have difficulty receiving the response PPDUs transmitted from the multiple STAs. Alternatively, if the information contained in the preambles of the PPDUs to which the multiple STAs respond differs depending on the format, the AP that instructed or triggered the response may have difficulty receiving the response PPDUs transmitted from the multiple STAs.

[0119] Therefore, to solve this problem, when multiple STAs respond to a frame from an AP, the format of the responding PPDU and / or the type of information included in the preamble of the PPDU may be set to be the same. For example, when multiple STAs transmit HE TB PPDUs in response to a frame from an AP, the AP may transmit information such that the information included in the L-STF, L-LTF, L-SIG, RL-SIG, and HE-SIG-A is the same, or a convention may be established for the information included in the HE TB PPDU, so that the AP can successfully receive the preambles transmitted by the multiple STAs. However, if the HE TB PPDU, EHT TB PPDU, and NEXT TB PPDU are simultaneously transmitted in overlapping subbands, the TB PPDU formats may be different from each other, which may make it difficult for the AP to receive them.

[0120] According to an embodiment of the present invention, an HE STA can transmit an HE TB PPDU, an EHT STA can transmit either an EHT TB PPDU or an HE TB PPDU, and a NEXT STA can transmit either a NEXT TB PPDU, an EHT TB PPDU, or an HE TB PPDU. This is because a STA of a certain standard may include functionality of a previous standard, as described in FIG. 10.

[0121] As shown in Figure 11, when an AP transmits a frame to schedule the transmission of a TB PPDU to an HE STA and an EHT STA, and uses the frame to instruct or trigger the transmission of a TB PPDU, there may be no precise instruction or protocol for the TB PPDU format. In this case, the HE STA transmits an HE TB PPDU in response to the frame, and the EHT STA may respond with an EHT TB PPDU or an HE TB PPDU. In this case, the AP may have difficulty receiving the TB PPDU transmitted by the STA. If the AP does not successfully receive TB PPDUs from multiple STAs, the medium may be occupied, reducing transmission opportunities for other STAs, even though the transmission was unsuccessful.

[0122] Hereinafter, in the present invention, instructing an STA can mean instructing a response from the STA, and the terms trigger and instruction may be used interchangeably.

[0123] Furthermore, the HE trigger frame, EHT trigger frame, and NEXT trigger frame may be trigger frames defined in the HE, EHT, and NEXT standards, respectively. Furthermore, in the present invention, the HE TRS, EHT TRS, and NEXT TRS may be TRSs defined in the HE, EHT, and NEXT standards, respectively.

[0124] FIG. 12 shows a trigger frame format according to an embodiment of the present invention.

[0125] (a) of Figure 12 shows the trigger frame format, and (b) and (c) of Figure 12 show the common info(information) field and the user info field, respectively, which are fields included in the trigger frame.

[0126] 12(a), as a trigger MAC header, a frame may include a Frame Control field, a Duration field, an Address field, a Common Information field, and a User Information List field. The Address field may include a Resource Allocation (RA) field and a Transmitter Address (TA) field.

[0127] The common information field can include information that is common to all STAs designated by the trigger frame. Figure 12(b) shows an example of the common information field.

[0128] The user information list field can include zero or more user information fields, and the user information list field of a trigger frame other than a specific type of trigger frame can include one or more user information fields. Figure 12(c) shows an example of a user information field.

[0129] The trigger frame may further include a padding field and a frame check sequence (FCS) field. The padding field may be used to increase the length of the frame to allow time for a STA receiving the trigger frame to prepare a response to the trigger frame, and may be optionally included in the trigger frame.

[0130] Referring to (b) of FIG. 12, the common information field may include a trigger type subfield. The trigger type subfield may be used to identify a trigger frame variant. Alternatively, the type of trigger frame may be indicated based on the value of the trigger frame subfield. Furthermore, the information and length included in the trigger dependent common information subfield and the trigger dependent user information subfield shown in FIG. 12 may be determined based on the trigger type subfield. For example, the trigger type subfield may be indicated by bits B0 to B3 of the common information field.

[0131] The common information field may include an Uplink (UL) length subfield. The UL length subfield may include information regarding the length of a TB PPDU, which is a response to the trigger frame, or may include information regarding the length of a frame responding to the trigger frame. In addition, the UL length subfield may indicate a value included in the length subfield of the L-SIG of the TB PPDU responding to the trigger frame. Therefore, a STA that receives a trigger frame and responds with a TB PPDU can set the value of the length subfield included in the L-SIG of the TB PPDU based on the value of the UL length subfield included in the received trigger frame. Specifically, a STA that responds with a TB PPDU can set the length subfield included in the L-SIG of the TB PPDU to the value of the UL length subfield included in the received trigger frame. For example, the STA can set the length subfield included in the L-SIG of the TB PPDU based on the value of bits B4 to B15 of the common information field, which indicate the UL length subfield, and transmit the TB PPDU.

[0132] The common information field may further include an uplink bandwidth subfield (UL Bandwidth (BW) subfield). The UL BW subfield may indicate a BW value included in a signaling field (e.g., HE-SIG-A or U-SIG) of a TB PPDU responding to the trigger frame, and may indicate the maximum BW of a TB PPDU transmitted in response to the trigger frame. Therefore, the STA may set the BW value included in the signaling field of the TB PPDU based on the value of the UL BW subfield included in the trigger frame.

[0133] In addition, the common information field may further include information included in the signaling field of the TB PPDU, which is a response to the trigger frame. Therefore, after receiving the trigger frame, the STA can set the information included in the TB PPDU based on the information included in the trigger frame.

[0134] Referring to (c) of FIG. 12, the user information field may include an AID12 subfield. The AID12 subfield may be used to indicate the intended recipient of the user information field including the AID12 subfield or the function of the user information field. Therefore, the AID12 subfield may also serve to indicate the intended recipient of a trigger frame including the AID12 subfield or the function of the trigger frame. For example, if the value of the AID12 subfield is a pre-configured value, the user information field may indicate a Random Access Resource Unit (RA-RU). That is, the pre-configured value of the AID12 subfield may indicate that the user information field indicates an RA-RU. Specifically, if the value of the AID12 subfield is '0', the user information field may indicate an RA-RU for associated STAs. For example, if the value of the AID12 subfield is "0", the user information field can indicate an RA-RU for associated STAs, and if the value of the AID12 subfield is "2045", the user information field can indicate an RA-RU for unassociated STAs. STAs corresponding to the STA ID (e.g., AID (association ID)) indicated by the value of the AID12 subfield may be instructed to respond by a user information field including the AID12 subfield or a trigger frame including the AID subfield. For example, the AID12 subfield can indicate the AID or 12 LSBs of the AID. STAs corresponding to the value indicated by the AID12 subfield can transmit a TB PPDU in response to the received trigger frame. In this case, the value of the AID12 subfield may be in the range of "1" to "2007" (including 1 and 2007), and if the AID12 subfield is a value that has already been set (e.g., "2046"), the RU corresponding to the already set value of the AID12 subfield may not be assigned to any STA.Also, if the AID subfield is a pre-set value (e.g., "4095"), the pre-set value may indicate the start of padding for the trigger frame.

[0135] Information in the user information field including the AID12 subfield may be information corresponding to the STA indicated by the AID12 subfield. For example, the Resource Unit (RU) Allocation subfield may indicate the size and location of the RU. In this case, the value of the RU Allocation subfield in the user information field including the AID12 subfield may be information corresponding to the STA indicated by the AID12 subfield. That is, the RU indicated by the RU Allocation subfield in the AID12 subfield may be the RU allocated to the STA indicated by the AID12 subfield.

[0136] The user information field may also indicate the coding method (UL FEC coding type), modulation method (UL HE-MCS, UL DCM), and power (UL Targer RSSI) for generating the TB PPDU to be transmitted in response to the trigger frame.

[0137] FIG. 13 illustrates UL MU operation according to yet another embodiment of the present invention.

[0138] 13, when an AP instructs transmission of a PPDU using a trigger frame, the STAs can respond with PPDUs of different formats based on the trigger frame. The embodiment described in FIG. 13 may be a method for solving the problems described in FIG. 10 and FIG. 11, and the above content will not be repeated.

[0139] Specifically, the EHT STA does not need to transmit an HE TB PPDU, does not need to perform HE UL MU operations, and can respond to a trigger frame or TRS (e.g., a PPDU including a TRS control subfield) in the EHT TB PPDU format.

[0140] An STA may transmit only a TB PPDU corresponding to the latest standard that the STA can support, and may not transmit a TB PPDU corresponding to an older standard. That is, a NEXT STA may transmit only a NEXT TB PPDU, and may not transmit an HE TB PPDU corresponding to an older standard. Also, a NEXT STA may perform a NEXT UL MU operation, but may not perform an HE UL MU operation. That is, an EHT STA may transmit only an EHT TB PPDU in response to an AP trigger frame, and may only perform an EHT UL MU operation.

[0141] Therefore, a STA responding to a trigger frame or TRS does not need to select the format of the TB PPDU to respond with, and this method has the advantage of simplifying the implementation of a STA responding to a trigger frame or TRS.

[0142] Furthermore, a STA that transmits a trigger frame or TRS to instruct the transmission of a TB PPDU may also need to schedule the transmission of different TB PPDUs so that they do not overlap. That is, a STA that transmits a trigger frame or TRS may not instruct a STA responding to the trigger frame or TRS as an HE STA, an EHT STA, and / or a NEXT STA. Or, a STA that transmits a trigger frame or TRS may not instruct a STA responding to the trigger frame or TRS as an HE STA, an EHT STA, and / or a NEXT STA using a single PPDU. Or, a HE trigger frame (or TRS), an EHT trigger frame (or TRS), and a NEXT trigger frame (or TRS) may not be included in a single PPDU, or a single trigger frame may not instruct a HE STA, an EHT STA, or a NEXT STA. Or, a HE trigger frame may not instruct a EHT STA or a NEXT STA. However, there may be an exception when indicating a combined PPDU (a PPDU in which multiple PPDUs exist in the form of frequency domain division). In the present invention, the HE STA may refer to an HE STA that is not an EHT STA but is not a NEXT STA. Also, the EHT STA may refer to an EHT STA that is not a NEXT STA.

[0143] Referring to Figure 13, the AP can transmit a trigger frame instructing only HE STAs. STAs receiving the trigger frame are HE STAs and can respond with an HE TB PPDU. The AP can transmit a trigger frame instructing only EHT STAs. STAs receiving the trigger frame instructing only EHT STAs are EHT STAs and can respond with an EHT TB PPDU.

[0144] That is, in the embodiment of Figure 13, the problems described in Figures 10 and 11 can be solved by restricting the TB PPDU format of the STA that responds to the trigger frame or TRS and scheduling the trigger frame or TRS accordingly.

[0145] FIG. 14 illustrates UL MU operation according to yet another embodiment of the present invention.

[0146] Referring to FIG. 14, an Access Point (AP) can transmit one trigger frame to instruct one or more non-AP STAs to transmit PPDUs of different formats.

[0147] Specifically, the method described in Figure 14 may be a method for solving the problems described in Figures 10 and 11, and may be an exceptional case of the method described in Figure 13. The method of Figure 14 may be an exceptional case of the method of transmitting a trigger frame or TRS, which is the method described in Figure 13. The above content may be equally applied to this method, and therefore the description thereof will be omitted.

[0148] When instructing an aggregated PPDU, the AP can instruct all of the HE STAs, EHT STAs, and / or NEXT STAs to transmit PPDUs. In this case, the HE TB PPDU, EHT TB PPDU, and / or NEXT TB PPDU transmitted in response may be scheduled so as not to overlap in the frequency domain. Alternatively, the 20 MHz subchannel including the RU, which is the resource unit of the HE TB PPDU, and the 20 MHz subchannel including the RU of the EHT TB PPDU may be allocated so as not to overlap with each other.

[0149] If the combined PPDU includes an HE PPDU, the HE PPDU must be present in an area including the primary channel, but if the combined PPDU is a TB PPDU, the HE PPDU may be present in an area not including the primary channel.

[0150] 14, in response to one trigger frame, multiple STAs may transmit an HE TB PPDU and an EHT TB PPDU. At this time, the HE TB PPDU and the EHT TB PPDU may be transmitted in non-overlapping RUs. That is, one trigger frame may instruct multiple STAs to transmit TB PPDUs of different formats, and the RUs for transmitting the TB PPDUs of different formats may not overlap. Therefore, multiple STAs can transmit PPDUs of different formats (e.g., HE TB PPDU and EHT TB PPDU) using different RUs on the frequency axis based on the transmitted trigger frame.

[0151] FIG. 15 illustrates a method for indicating a trigger-based PPDU format according to one embodiment of the present invention.

[0152] Referring to FIG. 15, one STA can selectively transmit PPDUs of different formats based on instructions from a triggering frame instructing transmission of the PPDU.

[0153] Specifically, an EHT STA can selectively transmit not only a legacy PPDU (e.g., an HE TB PPDU) but also an EHT TB PPDU, and a NEXT STA can selectively transmit an HE TB PPDU, an EHT TB PPDU, and / or a NEXT TB PPDU. In this case, STAs to which multiple standards are applied can be individually scheduled using one frame or one PPDU. This method can be advantageous because STAs to which multiple standards are applied share common resources in a WLAN. For example, an HE STA (an HE STA that is not an EHT STA) can respond with an HE TB PPDU using one frame. That is, a non-AP STA can transmit a triggering frame to instruct EHT STAs as well as HE STAs to transmit an HE TB PPDU.

[0154] In addition, information for selecting the TB PPDU format may be included in a trigger frame, which is a triggering frame, a PPDU including the TRS, or a PPDU including a TRS control subfield. That is, the AP STA includes information for selecting the TB PPDU format in a triggering frame and transmits it to at least one non-AP STA, and the non-AP STA can select the format of a responding PPDU based on the information included in the transmitted triggering frame. Then, the at least one non-AP STA can transmit a PPDU to the AP based on the selected format.

[0155] Information on the format of the PPDU (TB PPDU format) which is a response to such a triggering frame may exist at the MAC level, and a trigger frame, which is one of the triggering frames, may be classified into an HE trigger frame, an EHT trigger frame, and a NEXT trigger frame, and responses to each trigger frame may be classified into an HE TB PPDU, an EHT TB PPDU, and a NEXT TB PPDU.

[0156] Furthermore, classifying trigger frames into HE trigger frames, EHT trigger frames, and NEXT trigger frames may be equivalent to classifying the TB PPDU formats, which are responses to trigger frames, into HE TB PPDU, EHT TB PPDU, and NEXT TB PPDU, respectively.

[0157] Whether the format of a trigger frame for distinguishing the format of a TB PPDU is an HE trigger frame, an EHT trigger frame, or a NEXT trigger frame may be identified based on a Frame Control field included in the MAC header. Specifically, the format of the trigger frame may be identified based on a Type subfield, a Subtype subfield, and / or a Control Frame Extension subfield. Furthermore, if the values ​​of the Type subfield, the Subtype subfield, and / or the Control Frame Extension subfield are pre-set values, the trigger frame may be identified as an HE trigger frame. If the values ​​of the Type subfield, the Subtype subfield, and / or the Control Frame Extension subfield are pre-set values, the trigger frame may be identified as an EHT trigger frame. Furthermore, if the values ​​of the Type subfield, the Subtype subfield, and / or the Control Frame Extension subfield are pre-set values, the trigger frame may be identified as a NEXT trigger frame.

[0158] For example, if the Type subfield is 01 (B3 B2) and the Subtype subfield is 0010 (B7 B6 B5 B4), the format of the frame including the Type subfield and the Subtype subfield may be an HE trigger frame. In this case, it may be necessary to further use the entries of the Type subfield (2 bits), the Subtype subfield (4 bits), and / or the Control Frame Extension subfield (4 bits), which are assigned limited numbers of bits, in the EHT standard and the NEXT standard.

[0159] Alternatively, whether the format of the trigger frame is an HE trigger frame or an EHT trigger frame may be identified based on the common information field included in the trigger frame. That is, the format of the PPDU transmitted in response to the trigger frame may be determined based on the value of a specific subfield (first subfield) included in the common information field. For example, a non-AP STA may select an HE TB PPDU or an EHT TB PPDU based on the value of the common information field and transmit it in the assigned RU. In this case, in addition to the common information field, a specific subfield (second subfield) of the user information field may also be used to identify the format of the PPDU.

[0160] That is, a variant for determining the format of a PPDU that is a response to the trigger frame may be determined based on the common information field of the trigger frame, and the format of the PPDU may be determined based on the determined variant. For example, if the variant for determining the format of the PPDU is determined to be the HE variant based on the common information field, the non-AP STA may respond with an HE TB PPDU, and if the variant for determining the format of the PPDU is determined to be the EHT variant based on the common information field, the non-AP STA may respond with an EHT TB PPDU.

[0161] In this case, the variant for determining the format of the PPDU may further use the user information field in addition to the common information field.

[0162] For example, a trigger frame may be distinguished as an HE trigger frame, an EHT trigger frame, or a NEXT trigger frame based on the trigger type subfield. For example, if the trigger type subfield value is a previously set value, the trigger frame may be an HE trigger frame. Alternatively, if the trigger type subfield value is a previously set value, the trigger frame may be an EHT trigger frame. Alternatively, if the trigger type subfield value is a previously set value, the trigger frame may be a NEXT trigger frame.

[0163] For example, if the trigger type subfield value is 0 to 7, it is an HE trigger frame, and if it is not 0 to 7, it may be an EHT trigger frame or a NEXT trigger frame. The trigger type subfield indicates various trigger frame types, but in this case, there may be a disadvantage that a limited trigger type subfield space must be used.

[0164] According to still another embodiment, the trigger frame may be distinguished as an HE trigger frame, an EHT trigger frame, or a NEXT trigger frame based on the UL length subfield of the trigger frame. For example, the trigger frame may be distinguished as an HE trigger frame, an EHT trigger frame, or a NEXT trigger frame based on a value obtained by modulating the UL length subfield value. That is, the value of the UL length subfield may be used to determine whether the format of the PPDU transmitted in response to the trigger frame is an HE PPDU or an EHT PPDU.

[0165] More specifically, whether the trigger frame is an HE trigger frame, an EHT trigger frame, or a NEXT trigger frame can be determined based on the value obtained by modulating the UL length subfield value modulo (remainder) 3 (the remainder when the UL length subfield is divided by 3). For example, if the result of modulating the UL length subfield value modulo 3 is not 0, the trigger frame may be an HE trigger frame. Alternatively, if the result of modulating the UL length subfield value modulo 3 is 1, the trigger frame may be an HE trigger frame. Alternatively, if the result of modulating the UL length subfield value modulo 3 is 0, the trigger frame may be an EHT trigger frame or a NEXT trigger frame.

[0166] That is, if the value modulo 3 of the UL length subfield of the trigger frame is not 0, the response to the trigger frame may be transmitted in an HE TB PPDU, and if the value modulo 3 of the UL length subfield is 1, the response to the trigger frame may be transmitted in an HE TB PPDU.

[0167] Furthermore, when the value modulo 3 of the UL length subfield of the trigger frame is 0, the format of the PPDU transmitted in response to the trigger frame may be EHT TB PPDU.

[0168] In addition to the above method, it is also possible to distinguish between HE trigger frames, EHT trigger frames, and NEXT trigger frames using an additional trigger frame distinction method. For example, it is possible to distinguish between HE trigger frames, EHT trigger frames, and NEXT trigger frames by using the distinction method described in FIG. 16 together.

[0169] According to one embodiment, it is possible to distinguish whether the format of the trigger frame is an HE trigger frame, an EHT trigger frame, or a NEXT trigger frame based on the User Info field of the trigger frame.

[0170] That is, similar to the above-described common information field, whether the format of the trigger frame is an HE trigger frame or an EHT trigger frame may be identified based on the user information field included in the trigger frame. That is, the format of the PPDU transmitted in response to the trigger frame may be determined based on the value of a specific subfield (second subfield) included in the user information field. For example, depending on the value of the user information field, a non-AP STA may select an HE TB PPDU or an EHT TB PPDU and transmit it in the assigned RU. In this case, in addition to the user information field, a specific subfield (first subfield) of the common information field may also be used to identify the format of the PPDU.

[0171] That is, a variant for determining the format of a PPDU that is a response to the trigger frame may be determined based on the user information field of the trigger frame, and the format of the PPDU may be determined based on the determined variant. For example, if the user information field determines that the variant for determining the PPDU format is the HE variant, the non-AP STA may respond with an HE TB PPDU, and if the user information field determines that the variant for determining the PPDU format is the EHT variant, the non-AP STA may respond with an EHT TB PPDU.

[0172] In this case, the variant for determining the format of the PPDU may further include a common information field in addition to the user information field.

[0173] For example, a frame may be distinguished as an HE trigger frame, an EHT trigger frame, or a NEXT trigger frame based on the AID12 subfield. According to one embodiment, a frame may be distinguished as an HE trigger frame, an EHT trigger frame, or a NEXT trigger frame based on whether or not it includes an AID12 subfield with a preset value. In this case, a problem may arise as to whether a STA indicated by a certain user information field should continue to check the AID12 subfield present after the user information field to determine the trigger frame format. To solve this problem, a user information field including an AID12 subfield indicating the type of trigger frame may be present before the user information list. In addition, to prevent HE STAs that cannot understand this signaling method from malfunctioning, a user information field including an AID12 subfield indicating the type of trigger frame may be present after the user information field corresponding to the HE STA.

[0174] In addition, information on subfields other than the AID12 subfield included in the user information field is not necessary for the TB PPDU response, and subfields of the user information field including the AID12 subfield, which indicate the type of trigger frame, may be omitted. That is, the length of the user information field may vary depending on the AID12 subfield. Referring to FIG. 15, the AID12 subfield may serve to indicate the format of the TB PPDU to be responded to. For example, if the AID12 subfield is a pre-set value, the response to the trigger frame including the AID12 subfield set to the pre-set value may be an EHT TB PPDU. For example, if the AID12 subfield value is 2047, the response to the trigger frame including the AID12 subfield may be an EHT TB PPDU. Furthermore, if the AID12 subfield is a pre-set value, the response to the trigger frame including the AID12 subfield set to the pre-set value may be a NEXT TB PPDU. For example, if the AID12 subfield value is 2048, the response to a trigger frame containing the AID12 subfield may be a NEXT TB PPDU.

[0175] According to another embodiment, when responding based on a user information field located at a pre-set position from the AID12 subfield of a pre-set value, the response can be made in a TB PPDU format corresponding to the pre-set value. For example, when responding based on a user information field located after the AID12 subfield of a pre-set value, the response can be made in a TB PPDU format corresponding to the pre-set value. If there are multiple values ​​indicating a TB PPDU format, when responding based on a user information field located after both the pre-set value 1 and the pre-set value 2, the response can be made in a TB PPDU format according to the pre-set priority between the TB PPDU format corresponding to the pre-set value 1 and the TB PPDU format corresponding to the pre-set value 2. Referring to FIG. 15, when responding based on a user information field located after the AID12 subfield set to 2047, the response can be made in an EHT TB PPDU. Also, when responding based on a user information field located after the AID12 subfield set to 2048, the response can be made in a NEXT TB PPDU. Furthermore, when responding based on a user information field that exists after both the AID12 subfield set to 2047 and the AID12 subfield set to 2048, the NEXT TB PPDU can be used to respond. When responding based on a user information field that exists before both the AID12 subfield set to 2047 and the AID12 subfield set to 2048, the HE TB PPDU can be used to respond.

[0176] In this embodiment, an example is given in which the AID12 subfield indicates the type of trigger frame, but the present invention is not limited to this, and it is also possible to indicate the type of trigger frame using other subfields of the user information field.

[0177] According to one embodiment, whether the trigger frame is an HE trigger frame, an EHT trigger frame, or a NEXT trigger frame may be determined based on the padding field of the trigger frame. For example, whether the trigger frame is an HE trigger frame, an EHT trigger frame, or a NEXT trigger frame can be determined based on whether the padding field includes a pre-defined value indicating whether the trigger frame is an HE trigger frame, an EHT trigger frame, or a NEXT trigger frame.

[0178] According to an embodiment of the present invention, it is possible to distinguish between an HE trigger frame, an EHT trigger frame, and a NEXT trigger frame by combining a plurality of trigger frame distinction methods described in the present invention. Furthermore, the description of the trigger frame in the present invention is not limited thereto and can also be applied to a TRS.

[0179] In yet another embodiment of the present invention, the AP may not use a triggering frame to instruct transmission of both the EHT PPDU and the HE PPDU, i.e., the EHT AP may not transmit a trigger frame instructing both the HE TB PPDU and the EHT TB PPDU, but may instead instruct only one PPDU format.

[0180] FIG. 16 shows a trigger frame format for indicating a trigger-based PPDU format according to one embodiment of the present invention.

[0181] Referring to FIG. 16, the trigger frame may include information indicating the format of the trigger frame and the format of the PPDU to be sent in response to the trigger frame, and the content and length included in the trigger frame may vary depending on the indicated PPDU format.

[0182] Specifically, the trigger frame may include information indicating the format of the trigger frame, i.e., whether the trigger frame is an HE trigger frame, an EHT trigger frame, or a NEXT trigger frame, and therefore may include information for determining the format of the PPDU indicated by the trigger frame.

[0183] Furthermore, the content and length of the trigger frame may vary depending on the information indicating the format, and the trigger frame may include information indicating whether an HE TB PPDU, an EHT TB PPDU, or a NEXT TB PPDU should be transmitted in response to the trigger frame. For example, the information indicating the format of the trigger frame or the information indicating the TB PPDU format in response to the trigger frame may be included in a format identifier subfield.

[0184] Therefore, the format of the trigger frame can be determined based on the format identifier subfield. Also, the format of the TB PPDU to be responded to can be determined based on the format identifier subfield. That is, it is possible to respond with a standard TB PPDU corresponding to the value indicated by the format identifier subfield. According to one embodiment, the format identifier subfield may be 3 bits long. Also, the format identifier subfield may be located after B16 of the common information field.

[0185] For example, the format identifier subfield may be located next to the UL length subfield. Furthermore, since the trigger frame described in FIG. 12 has a format that can be understood by HE STAs, the format identifier subfield may be located in a trigger frame that conforms to the EHT standard or later. That is, when a trigger frame includes a format identifier subfield, the trigger frame may be an EHT trigger frame or a NEXT trigger frame. Alternatively, when a trigger frame includes a format identifier subfield, a TB PPDU responding to the trigger frame may be an EHT TB PPDU or a NEXT TB PPDU. In this case, the values ​​that the format identifier subfield can indicate may conform to the EHT standard or later.

[0186] According to one embodiment, the U-SIG field included in the TB PPDU may be based on the PPDU indicating the TB PPDU. According to one embodiment, the U-SIG field included in the TB PPDU may be based on the trigger frame indicating the TB PPDU. More specifically, the U-SIG field included in the TB PPDU may be based on the format identifier subfield included in the trigger frame indicating the TB PPDU.

[0187] For example, the PHY version identifier of the U-SIG field included in the TB PPDU may be based on the format identifier subfield included in the trigger frame that indicated the TB PPDU. The PHY version identifier indicates the PHY version of the PPDU transmitted by a non-AP STA or an AP. For example, if the value of the PHY version identifier is set to '0', this means that the corresponding PPDU is an EHT PPDU whose PHY version is EHT.

[0188] The PHY version identifier may be used to identify whether the format of the PPDU is an EHT PPDU and may be set based on the format identifier included in the trigger frame. For example, a non-AP STA may set the value of the PHY version field included in the PPDU to be the same as the value of the format identifier included in the trigger frame. Therefore, a non-AP STA can determine whether the format of the PPDU to be transmitted is an EHT TB PPDU based on the value of the format identifier included in the trigger frame.

[0189] For example, the PHY version identifier value of the U-SIG field included in the TB PPDU may be set to the same value as the format identifier subfield included in the trigger frame indicating the TB PPDU. Alternatively, if the standard ranges indicated by the PHY version identifier subfield of the U-SIG field and the format identifier subfield of the trigger frame are different, the PHY version identifier value of the U-SIG field included in the TB PPDU may be set to a value obtained by adding / subtracting a previously set value to / from the format identifier subfield value included in the trigger frame indicating the TB PPDU.

[0190] The PHY version identifier subfield of the U-SIG field may be the PHY version field described above. The PHY version identifier subfield of the U-SIG field may also serve to indicate the format of the U-SIG field. The PHY version identifier subfield of the U-SIG field may also serve to indicate the PHY version of the PPDU including the U-SIG field.

[0191] 16, the trigger frame may include a format identifier subfield, and based on the format identifier subfield, it may be determined what standard trigger frame the trigger frame is, or what TB PPDU format should be used in response to the trigger frame.

[0192] Furthermore, the trigger frame may include information included in the U-SIG field of the TB PPDU responding to the trigger frame. For example, the trigger frame may include information included in a version independent field and a version dependent field of the U-SIG field. The information included in the U-SIG field may include information included in the version independent field and the version dependent field.

[0193] The information included in the version-independent field of the U-SIG field may be U-SIG version-independent content. The information included in the version-dependent field of the U-SIG field may be U-SIG version-dependent content. Furthermore, the above-mentioned format identifier subfield may be one of the U-SIG version-independent content. According to an embodiment of the present invention, the content and length of the information included in the U-SIG field of the TB PPDU included in the trigger frame may vary based on the format identifier subfield included in the trigger frame. For example, the content and length of the U-SIG version-dependent content of the TB PPDU included in the trigger frame may vary based on the format identifier subfield included in the trigger frame. For example, the U-SIG version-independent content may be a subfield having content and length independent of the format identifier subfield, and the U-SIG version-dependent content may be a subfield having content and length based on the format identifier subfield. According to an embodiment, the information included in the U-SIG field may be included in the common information field of the trigger frame. Furthermore, the U-SIG version-dependent content included in the trigger frame may include BW, puncturing information, etc.

[0194] 16, the trigger frame can include U-SIG version-independent content and U-SIG version-dependent content, and the content and length of the U-SIG version-independent content or U-SIG version-dependent content can vary based on the format identifier subfield.

[0195] FIG. 17 shows a trigger frame format for indicating a trigger-based PPDU format according to yet another embodiment of the present invention.

[0196] Referring to FIG. 17, the STA can determine the format of the PPDU to be transmitted based on the subfields included in the common information field and / or the user information field included in the triggering frame.

[0197] Specifically, Figure 17(a) shows an example of a common information field included in a trigger frame, Figure 17(b) shows an example of a user information field, and Figure 17(c) shows an example of a special user information field.

[0198] Among the fields shown in (a) to (c) of FIG. 17, the description of the same fields as those described above will be omitted.

[0199] 17(a) may be used to identify the format of the PPDU indicated by the trigger frame, as described above. For example, the common information field of the trigger frame may be used to identify whether the format of the PPDU indicated by the trigger frame is an EHT TB PPDU or an HE TB PPDU.

[0200] Specifically, in the common information field shown in (a) of Figure 17, the HE / EHT P160 subfield (first subfield) indicates the format of the PPDU transmitted on the 160 MHz primary channel. For example, a value of "1" in the HE / EHT P160 subfield indicates transmission of the HE TB PPDU on the 160 MHz primary channel, and a value of "0" indicates transmission of the EHT TB PPDU on the 160 MHz primary channel.

[0201] The user information field in FIG. 17(b) may be used to identify the format of the PPDU indicated by the trigger frame, as described above.

[0202] Specifically, in the user information field shown in (b) of Figure 17, the PS160 subfield (second subfield) indicates where the RU allocated by the RU allocation field of the user information field is located in the 160 MHz primary channel or secondary channel.

[0203] The PS160 subfield, together with the HE / EHT P160 subfield in (a) of Figure 17, is used to indicate the format of the PPDU indicated by the trigger frame. For example, if the value of the HE / EHT P160 subfield is set to "1" to indicate transmission of an HE TB PPDU on the primary channel, setting the value of the PS160 subfield to "0" indicates that an RU has been assigned to the primary channel, and the STA transmits a response to the trigger frame with an HE TB PPDU on the primary channel.

[0204] However, when the value of the HE / EHT P160 subfield is set to "1" and indicates the transmission of an HE TB PPDU on the primary channel, if the value of the PS160 subfield is set to "1", this indicates that an RU is assigned to the secondary channel, so the STA transmits a PPDU on the secondary channel, and the format of the PPDU is EHT TB PPDU.

[0205] Table 1 below shows an example of a PPDU format with the HE / EHT P160 subfield and PS160 subfield.

[0206] [Table 1]

[0207] Referring to Table 1, bit B54 of the common information field indicates the value of the HE / EHT P160 subfield, and bit B39 indicates the value of the PS160 subfield. The value of the HE / EHT P160 subfield and the value of the PS160 subfield determine the variant for determining the PPDU format, and the determined variant determines whether the PPDU type is HE or EHT.

[0208] Using the common information field and / or user information field included in the trigger frame, the STA determines whether the format of the PPDU to be sent in response to the trigger frame is EHT or HE, and generates and sends the PPDU to the AP in the determined format.

[0209] 17(c) shows an example of the special user information field including the PHY version identifier described above, which is used to identify whether the PHY version is EHT or not, as described above, and may be set based on the format indicator of the trigger frame.

[0210] FIG. 18 shows a method for determining a trigger frame format according to an embodiment of the present invention.

[0211] FIG. 18 may be used in association with the embodiment described above with reference to FIGS. 15 to 17, and the details described above will be omitted.

[0212] Specifically, as illustrated in FIG. 16, the trigger frame may include a format indicator subfield. Also, the trigger frame or the HE trigger frame illustrated in FIG. 12 may not include a format indicator subfield. Therefore, a method for determining whether a trigger frame includes a format indicator subfield may be necessary. According to an embodiment, the trigger frame may include information indicating whether it includes a format indicator subfield. For example, the common information field of the trigger frame may include information indicating whether it includes a format indicator subfield. More specifically, the trigger type subfield of the trigger frame may include information indicating whether it includes a format indicator subfield. For example, whether the trigger type subfield includes a pre-set value may determine whether it includes a format indicator subfield. For example, if the trigger type subfield is a value between 0 and 7, the trigger frame may not include a format indicator subfield. Also, if the trigger type subfield is not a value between 0 and 7 or if the trigger type subfield is a value between 8 and 15, the trigger frame may include a format indicator subfield. Also, when the trigger type subfield is 0 to 7, it can indicate Basic, Beamforming Report Poll (BFRP), MU-BAR, MU-RTS, Buffer Status Report Poll (BSRP), GCR MU-BAR, Bandwidth Query Report Poll (BQRP), or NDP Feedback Report Poll (NFRP), respectively. In this case, when the trigger type subfield is 8 to 15, it can indicate a trigger frame type when the trigger type subfield is 0 to 7, but can also indicate a trigger frame format that does not include a format indicator subfield.

[0213] According to still another embodiment, whether a format indicator subfield is included can be determined based on the UL length subfield of the trigger frame. For example, whether a format indicator subfield is included can be determined by the trigger frame discrimination method based on the UL length subfield described with reference to FIG. 15. That is, whether a format indicator subfield is included can be determined based on the result of modulating the value of the UL length subfield, more specifically, the result of modulating the value of the UL length subfield.

[0214] For example, if the modulo 3 calculation result of the value of the UL length subfield is not 0, the format indicator subfield may not be included, and if the modulo 3 calculation result is 0, the format indicator subfield may be included. This may be combined with the above-mentioned embodiment in which the EHT trigger frame and the NEXT trigger frame include a format indicator subfield, and the above-mentioned embodiment in which it is determined whether the frame is an HE trigger frame based on the modulo 3 calculation result of the UL length subfield.

[0215] Referring to Figure 18, it is possible to determine whether the trigger frame is an HE trigger frame or whether the trigger frame includes a format indicator subfield based on the UL length subfield included in the trigger frame. For example, if the value of ((UL length subfield value) mod 3) is not 0, it can be determined that the trigger frame is a trigger frame (or an HE trigger frame) having a common information field and a user information field as described in Figure 12 and does not include a format indicator subfield. Furthermore, when responding to the trigger frame, it can respond with an HE TB PPDU.

[0216] Also, if the value of ((UL Length subfield value) mod 3) is 0, it can be determined that the trigger frame is an EHT trigger frame or a NEXT trigger frame and includes a format indicator subfield. Furthermore, the remaining information included in the trigger frame (i.e., common information field, user information field) can be determined based on the value indicated by the format indicator subfield. Furthermore, when responding to the trigger frame, it can respond with a TB PPDU of the standard indicated by the format indicator subfield. That is, if the format indicator subfield indicates the EHT standard, it can respond with an EHT TB PPDU. Furthermore, if the format indicator subfield indicates the NEXT standard, it can respond with a NEXT TB PPDU.

[0217] A method for setting a length field according to an embodiment of the present invention is shown in Fig. 19. In the embodiment of Fig. 19, the contents described in Figs. 15 to 18 may be omitted.

[0218] Referring to FIG. 19, a PPDU transmitted in response to a trigger frame may include a length field having a different value depending on the format.

[0219] Specifically, the trigger frame may include a UL length subfield, which may indicate information related to the length of the PPDU indicated by the trigger frame. For example, the UL length subfield may indicate information related to the value of a length field included in the L-SIG field of a PPDU transmitted in response to the trigger frame. The length field included in the L-SIG field may be length or duration information included in a legacy preamble. The length field included in the L-SIG field may be represented as L_LENGTH or LENGTH, which may be set by a transmission parameter or a reception parameter value.

[0220] According to an embodiment of the present invention, a method for setting a length field included in the L-SIG field of the TB PPDU using a UL length subfield included in the trigger frame may vary depending on the format of the TB PPDU transmitted in response to the trigger frame. Also, according to an embodiment of the present invention, a method for setting a length field included in the L-SIG field of the TB PPDU using a UL length subfield included in the trigger frame may vary depending on the format of the trigger frame. Alternatively, according to an embodiment of the present invention, a method for setting a length field included in the L-SIG field of the TB PPDU using a UL length subfield included in the trigger frame may vary depending on a value based on the value of the UL length subfield of the trigger frame.

[0221] As mentioned above, there may be cases where the value of the UL length subfield included in the trigger frame is not 0 when modulo 3, which is a modular operation, is used, and it is possible to respond with an HE TB PPDU, EHT TB PPDU, or NEXT TB PPDU based on the trigger frame.

[0222] If the value obtained by modulating the value of the UL length subfield included in the trigger frame is not 0, when an HE TB PPDU is transmitted in response to the trigger frame, the length field of the L-SIG field included in the HE TB PPDU may be set to the same value as the value of the UL length subfield of the trigger frame. This is to ensure that the value obtained by modulating the value of the length field included in the L-SIG field of the HE TB PPDU is set to a non-zero value (e.g., 1).

[0223] Furthermore, if the value modulo 3 of the value of the UL length subfield included in the trigger frame is not 0, when an EHT TB PPDU or a NEXT TB PPDU is transmitted in response to the trigger frame, the length field of the L-SIG field included in the HE TB PPDU may be set to a value obtained by adding a previously set value to the value of the UL length subfield of the trigger frame. In this case, the previously set value may be 2 or -1. This is to ensure that the value modulo 3 of the length field included in the L-SIG field of the HE TB PPDU becomes 0.

[0224] That is, when the format of the PPDU indicated by the trigger frame is an HE TB PPDU and a non-AP STA transmits an HE TB PPDU in response to the trigger frame, the value of the L_LENGTH parameter, which is the value of the length field included in the L-SIG field of the TB PPDU, may be set to the value indicated by the UL length subfield included in the common information field of the trigger frame.

[0225] However, when the format of the PPDU indicated by the trigger frame is EHT TB PPDU or NEXT TB PPDU, and a non-AP STA transmits an EHT TB PPDU or NEXT TB PPDU in response to the trigger frame, the value of the L_LENGTH parameter, which is the value of the length field included in the L-SIG field of the TB PPDU, may be set to the value of the transmission parameter L_LENGTH parameter, which is the value indicated by the UL length subfield included in the common information field of the trigger frame, plus a previously set value (e.g., 2 or -1).

[0226] In this case, Length, which is the L_LENGTH value, may be calculated by the following Equation 4.

[0227]

number

[0228] As mentioned above, there may be cases where the value modulated 3 of the UL length subfield value included in the trigger frame is 0. Also, as mentioned above, it is possible to respond with an HE TB PPDU, EHT TB PPDU, or NEXT TB PPDU based on the trigger frame.

[0229] When the value modulo 3 of the UL length subfield value included in the trigger frame is 0, if a response is made using an HE TB PPDU, the length field included in the L-SIG field included in the HE TB PPDU can be set to a value obtained by adding a pre-set value to the UL length subfield value. For example, the pre-set value may be (-2). This may be to make the value modulo 3 of the length field included in the L-SIG field of the HE TB PPDU a non-zero value, for example, 1. In yet another embodiment, the pre-set value may be 1.

[0230] If the value modulated 3 of the UL Length subfield included in the trigger frame is 0, when responding with an EHT TB PPDU or NEXT TB PPDU, the length field included in the L-SIG field included in the EHT TB PPDU or NEXT TB PPDU can be set to the same value as the value of the UL Length subfield. This may be to set the value modulated 3 of the length field included in the L-SIG field of the EHT TB PPDU or NEXT TB PPDU to 0.

[0231] FIG. 20 illustrates UL MU operation according to yet another embodiment of the present invention.

[0232] The embodiment of Fig. 20 may be a method for solving the problems described in Fig. 10 and Fig. 11. Also, the embodiment of Fig. 20 may be an explanation of another method for distinguishing trigger frames in the embodiment described in Fig. 15. Also, the above content may be omitted.

[0233] According to one embodiment of the present invention, an EHT STA can selectively transmit an HE TB PPDU or an EHT TB PPDU. Furthermore, a NEXT STA can selectively transmit an HE TB PPDU, an EHT TB PPDU, or a NEXT TB PPDU. This has the advantage that multi-standard STAs can be scheduled using one frame or one PPDU. This is advantageous because multi-standard STAs share common resources in a WLAN. For example, it is possible for an HE STA (a non-EHT HE STA) and an EHT STA to respond with an HE TB PPDU using one frame.

[0234] Furthermore, information for selecting the TB PPDU format may be included in the trigger frame, the TRS, or the PPDU containing the trigger frame, or the PPDU containing the TRS.

[0235] According to an embodiment of the present invention, information regarding the format of the responding TB PPDU may be present at the PHY level. According to an embodiment of the present invention, a HE trigger frame, an EHT trigger frame, and a NEXT trigger frame may be distinguished. Furthermore, responses indicated as an HE trigger frame, an EHT trigger frame, or a NEXT frame may be responded with an HE TB PPDU, an EHT TB PPDU, or a NEXT TB PPDU, respectively.

[0236] Furthermore, in the present invention, distinguishing between an HE trigger frame, an EHT trigger frame, and a NEXT trigger frame may mean the same as distinguishing the TB PPDU formats responding to the trigger frames into an HE TB PPDU, an EHT TB PPDU, and a NEXT TB PPDU, respectively.

[0237] According to an embodiment of the present invention, the TB PPDU format for responding to the trigger frame can be determined based on the PPDU format including the trigger frame. For example, it is possible to respond to the frame using a standard TB PPDU that is the same as the PPDU format including the trigger frame. Referring to FIG. 19, if the trigger frame is transmitted using an HE PPDU, the TB PPDU for responding to the trigger frame may be an HE TB PPDU. In this case, even if the trigger frame indicates an EHT STA or a NEXT STA, the response can be made using an HE TB PPDU. If the trigger frame is transmitted using an EHT PPDU, the TB PPDU for responding to the trigger frame may be an EHT TB PPDU. In this case, even if the trigger frame indicates a NEXT STA, the response can be made using an EHT TB PPDU.

[0238] Furthermore, when responding to a trigger frame included in an EHT PPDU or a NEXT PPDU, the PHY version identifier included in the U-SIG field of the TB PPDU responding to the EHT PPDU or the NEXT PPDU may be set to the same value as the PHY version identifier included in the U-SIG field of the EHT PPDU or the NEXT PPDU. The PHY version identifier included in the U-SIG field of the EHT PPDU or the NEXT PPDU may be a reception parameter, RXVECTOR, which may be transmitted from the PHY of the STA receiving the EHT PPDU or the NEXT PPDU to MAC. The PHY version identifier included in the U-SIG field of the TB PPDU responding to the EHT PPDU or the NEXT PPDU may be a TXVECTOR, which may be transmitted from the MAC of the STA transmitting the TB PPDU to PHY. That is, the TXVECTOR PHY version identifier of the STA responding with the TB PPDU may be set to the value of the RXVECTOR PHY version identifier when receiving a PPDU including a trigger frame indicating the TB PPDU.

[0239] According to one embodiment, it is possible to use both the MAC level distinction method described in Fig. 15 and the PHY level distinction method described in Fig. 20. For example, if a trigger frame is transmitted using a non-HT (duplicate) PPDU, the MAC level distinction method may be used. Also, if the results of the MAC level distinction method and the PHY level distinction method (which standard trigger frame or which standard TB PPDU should be used to respond) do not match, the previously set priority may be followed.

[0240] For example, if the results of the MAC level discrimination method and the PHY level discrimination method do not match, the PHY level discrimination method can be used. For example, if an EHT trigger frame is transmitted using an HE PPDU, it is possible to respond using an HE TB PPDU. This has the advantage that even an HE STA that cannot decode the PPDU of the later standard can decode the PPDU, check the preamble, receive the frame included in the PPDU, and appropriately protect the PPDU or the frame.

[0241] FIG. 21 illustrates UL MU operation according to yet another embodiment of the present invention.

[0242] As described above, in addition to the trigger frame, the TB PPDU may be indicated by the TRS. Also, as described above, the TRS may be included in the HT control field. For example, when the HT control field includes an A-control field, the TRS may be included. The TRS may be conveyed by the TRS control subfield. The A-control field may have a form in which the control list fields can be positioned consecutively. Also, the control list field may include the TRS.

[0243] In addition, a receiver of a frame including a TRS (indented receiver) can respond to the TRS. For example, a STA corresponding to an RA included in a frame including a TRS can respond to the TRS. The TRS can include information on the length of a PPDU or frame responding to the TRS (UL Data Symbols), the location and size of an RU used when responding to the TRS (RU Allocation), information on power when responding to the TRS (AP Tx Power, UL Target RSSI), and information on a modulation method when responding to the TRS (UL HE-MCS).

[0244] The embodiment of Fig. 21 may be a method for solving the problems described in Fig. 10 and Fig. 11. Also, as mentioned above, the above-mentioned embodiment for the trigger frame can also be applied to the TRS, and the above content may be omitted.

[0245] According to one embodiment of the present invention, in addition to the TRS defined in the HE standard (HE TRS), TRS defined in the EHT standard or the NEXT standard (EHT TRS and NEXT TRS, respectively) may exist. Therefore, depending on whether the indicated TRS is the HE TRS, EHT TRS, or NEXT TRS, the TB PPDU responding to the TRS may be the HE TB PPDU, EHT TB PPDU, or NEXT TB PPDU, respectively. For example, which standard the TRS is defined in may be determined by the Control ID subfield of the A-Control subfield. In an additional embodiment, the TRS may be classified into two types: the HE TRS and a TRS that is not the HE TRS.

[0246] Alternatively, for example, the TRS defined by which standard is used may be determined depending on whether the HT control field is an HE variant, an EHT variant, or a NEXT variant. Also, the HE variant, EHT variant, or NEXT variant may be determined using the values ​​of bits already set in the HT control field. For example, if B0 and B1 in the HT control field are 1, 1, it may be an HE variant. Also, the HE variant, EHT variant, or NEXT variant may be determined using B0 and B1 in the HT control field and an additional bit (e.g., B31).

[0247] According to one embodiment of the present invention, the TB PPDU format responding to the TRS may be determined based on the PPDU format including the TRS, as in the case of the trigger frame described with reference to Figure 20. That is, when a PPDU instructing PPDU transmission includes a TRS control subfield, the format of the PPDU may be determined based on the format of the PPDU including the TRS control subfield. For example, when the format of the PPDU including the TRS control subfield is HE PPDU, the format of the indicated PPDU may be HE PPDU. On the other hand, when the format of the PPDU including the TRS control subfield is EHT PPDU, the format of the indicated PPDU may be EHT PPDU.

[0248] 21, when a TRS is transmitted in an HE PPDU, a TB PPDU responding to the TRS may be an HE TB PPDU. When a TRS is transmitted in an EHT PPDU, a TB PPDU responding to the TRS may be an EHT TB PPDU. When a TRS is transmitted in a NEXT PPDU, a TB PPDU responding to the TRS may be a NEXT TB PPDU.

[0249] According to an embodiment of the present invention, the interpretation of a subfield included in the TRS may vary depending on the PPDU format in which the TRS is included. For example, when the TRS is included in an HE PPDU, the UL HE-MCS subfield (or a subfield related to MCS) included in the TRS may indicate a value corresponding to the HE MCS table. When the TRS is included in an EHT PPDU, the UL HE-MCS subfield (or a subfield related to MCS) included in the TRS may indicate a value corresponding to the EHT MCS table. When the TRS is included in a NEXT PPDU, the UL HE-MCS subfield (or a subfield related to MCS) included in the TRS may indicate a value corresponding to the NEXT MCS table. In addition, the interpretation of the RU Allocation subfield may also vary depending on the PPDU format in which the TRS is included.

[0250] FIG. 22 illustrates UL OFDMA (Orthogonal Frequency Division Multiple Access)-based random access (UORA) operation according to one embodiment of the present invention.

[0251] According to one embodiment, the UORA operation may be an operation of responding based on the RA-RU included in the trigger frame. For example, the OBO counter set by the STA is decremented based on the number of RA-RUs indicated by the trigger frame, and when the OBO counter becomes 0, the UORA operation may be an operation of responding to the trigger frame with the RA-RU indicated by the trigger frame.

[0252] FIG. 22 may be an operation for solving the problems described in FIGS. 10 and 11, and the above content may be omitted.

[0253] According to one embodiment of the present invention, not only the HE STA but also the EHT STA and the NEXT STA can decrement the OBO counter and send a UORA response to an RA-RU indicated by an HE trigger frame or a trigger frame included in an HE PPDU. Therefore, in this case, it may be necessary to respond with an HE TB PPDU. Similarly, when responding to an RA-RU indicated by an EHT trigger frame or a trigger frame included in an EHT PPDU, the response can be sent with an EHT TB PPDU. Furthermore, when responding to an RA-RU indicated by a NEXT trigger frame or a trigger frame included in a NEXT PPDU, the response can be sent with a NEXT TB PPDU.

[0254] According to one embodiment of the present invention, when responding with a TB PPDU to a trigger frame including an RA-RU, it is possible to respond with a TB PPDU corresponding to the most recent previous standard that can understand the trigger frame and the PPDU including the trigger frame.

[0255] Referring to FIG. 22, it is shown that the EHT STA responds to the HE trigger frame indicating the RA-RU with an HE TB PPDU when the OBO counter value becomes 0.

[0256] FIG. 23 illustrates UL MU operation according to yet another embodiment of the present invention.

[0257] According to one embodiment of the present invention, if a STA is the only STA indicated by a trigger frame or TRS, it can respond with any TB PPDU. Alternatively, if a STA is the only STA indicated by a trigger frame and TRS included in a PPDU containing a trigger frame or TRS, it can respond with any TB PPDU. In other words, in this case, the problems described in Figures 10 and 11 do not occur even if the embodiments described in Figures 13 to 22 are not applied.

[0258] According to an embodiment of the present invention, whether a STA is the designated only STA can be determined based on the number of user information fields included in the trigger frame. For example, a STA can be the designated only STA only if the trigger frame contains one user information field.

[0259] Furthermore, the RU received by the STA can be the only STA designated only if it is the only RU used by the PPDU containing the trigger frame or TRS.

[0260] Also, only if the RA of the frame received by the STA is an individual address that indicates the STA, the STA can be the only STA indicated.

[0261] Also, only if the PPDU received by the STA is a single user (SU) PPDU, can the STA be the only one designated.

[0262] According to one embodiment, it can be determined that a designated STA is the only STA when both of the above-described conditions are met.

[0263] According to one embodiment, the trigger frame, the TRS, or the PPDU including the trigger frame or the TRS may include information indicating that the responding TB PPDU format may be any TB PPDU format.

[0264] Referring to Figure 23, a trigger frame included in an SU PPDU may indicate a STA corresponding to AID12 value X. The trigger frame may include only one user information field. Also, the RU containing the trigger frame may be the only RU used by the PPDU containing the trigger frame. In this case, the TB PPDU responding to the trigger frame may be in any TB PPDU format. For example, if the STA corresponding to AID12 value X is an EHT STA, it may respond to the trigger frame with either an HE TB PPDU or an EHT TB PPDU.

[0265] FIG. 24 is a flowchart illustrating an example of a method for transmitting a PPDU according to an embodiment of the present invention.

[0266] Referring to FIG. 24, a non-AP STA receives a frame instructing transmission of a PPDU from an AP, and can transmit the PPDU based on the received frame.

[0267] Specifically, the non-AP STA can receive a frame instructing the transmission of a PPDU from the AP STA (S24010). At this time, the frame instructing the transmission of a PPDU can be a trigger frame or a PPDU.

[0268] The frame instructing the transmission of the PPDU may have the format described in Figures 12 to 17. For example, the frame may include a common information field and / or a user information field, and may further include a TRS control subfield instructing the transmission of the PPDU.

[0269] At least one of the common information field and the user information field may be used to identify whether the PPDU indicated by the trigger frame is an Extremely High Throughput (EHT) PPDU or a High Efficiency (HE) PPDU. Specifically, the common information field may include a first subfield indicating a format of a PPDU transmitted on a primary channel, and the user information field may include a second subfield indicating a location of a resource unit (RU) allocated to the terminal.

[0270] The first subfield indicates the transmission of the EHT PPDU or the HE PPDU on the primary channel of the 160 MHz band, and the second subfield can indicate where the RU assigned by the user information field is located in the primary channel or secondary channel.

[0271] The non-AP STA can identify the format of the PPDU instructed to be transmitted by the frame using at least one of the common information field and / or user information field included in the frame, and can transmit the PPDU to the AP in the identified format (S24020).

[0272] At this time, the PPDU is the EHT PPDU or the HE PPDU identified by at least one of the common information field and the user information field.

[0273] The PPDU includes a length field associated with the length of the PPDU, and the length field may be set to a different value depending on whether the PPDU is the EHT PPDU or the HE PPDU, as described in FIG. 19.

[0274] For example, if the PPDU is an HE PPDU, the length field may be set to the same value as the value of the length field included in the frame, and if the PPDU is an EHT PPDU, the length field may be set to the value of the length field included in the frame plus a specific value. In this case, the specific value may be 2, and if the value of the length field included in the frame is not a multiple of 3, the specific value may be used so that the value of the length field of the PPDU becomes a multiple of 3.

[0275] The PPDU includes a PHY version identifier (ID) subfield that indicates whether the PHY version of the PPDU is EHT, and the PHY version ID subfield may be set based on a format identifier subfield included in the frame that indicates the transmission of the PPDU.

[0276] Also, a frame cannot indicate the transmission of both the EHT PPDU and the HE PPDU.

[0277] FIG. 25 is a flowchart illustrating an example of a method for transmitting a frame for instructing transmission of a PPDU according to an embodiment of the present invention.

[0278] Specifically, the AP STA can transmit a frame instructing the non-AP STA to transmit a PPDU (S25010). At this time, the frame instructing the non-AP STA to transmit a PPDU may be a trigger frame or a PPDU.

[0279] The frame instructing the transmission of the PPDU may have the format described in Figures 12 to 17. For example, the frame may include a common information field and / or a user information field, and may further include a TRS control subfield instructing the transmission of the PPDU.

[0280] At least one of the common information field and the user information field may be used to identify whether the PPDU indicated by the trigger frame is an Extremely High Throughput (EHT) PPDU or a High Efficiency (HE) PPDU. Specifically, the common information field may include a first subfield indicating a format of a PPDU transmitted on a primary channel, and the user information field may include a second subfield indicating a location of a resource unit (RU) allocated to the terminal.

[0281] The first subfield indicates the transmission of the EHT PPDU or the HE PPDU on the primary channel of the 160 MHz band, and the second subfield can indicate where the RU assigned by the user information field is located in the primary channel or secondary channel.

[0282] The AP STA can receive a PPDU based on a format identified using at least one of a common information field and / or a user information field included in the frame (S25020).

[0283] In this case, the PPDU is the EHT PPDU or the HE PPDU identified by at least one of the common information field and the user information field.

[0284] The PPDU includes a length field associated with the length of the PPDU, and the length field may be set to a different value depending on whether the PPDU is the EHT PPDU or the HE PPDU, as described in FIG. 19.

[0285] For example, if the PPDU is an HE PPDU, the length field may be set to the same value as the value of the length field included in the frame, and if the PPDU is an EHT PPDU, the length field may be set to the value of the length field included in the frame plus a specific value. In this case, the specific value may be 2, and if the value of the length field included in the frame is not a multiple of 3, the specific value may be used so that the value of the length field of the PPDU becomes a multiple of 3.

[0286] The PPDU includes a PHY version identifier (ID) subfield that indicates whether the PHY version of the PPDU is EHT, and the PHY version ID subfield may be set based on a format identifier subfield included in the frame that indicates the transmission of the PPDU.

[0287] Also, a frame cannot indicate the transmission of both the EHT PPDU and the HE PPDU.

[0288] The above description of the present invention is for illustrative purposes only, and those skilled in the art will understand that the present invention can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. Therefore, it should be understood that the above-described embodiments are illustrative in all respects and are not limiting. For example, each component described as a single type may be implemented in a distributed form, and similarly, each component described as a distributed type may be implemented in a combined form.

[0289] The scope of the present invention is indicated by the claims set forth below rather than by the above detailed description, and any modifications or variations derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included within the scope of the present invention. [Explanation of symbols]

[0290] 100 Stations 110 processors 120 Communications Department 140 User Interface Section 150 display units 160 memory 210 processors 220 Communications Department 260 memory 300 servers

Claims

1. A terminal of a wireless communication system, a communication module; a processor configured to control the communication module; The processor: receiving a trigger frame from an access point (AP) instructing one or more terminals to transmit physical layer protocol data units (PPDUs); configured to transmit a trigger-based (TB) PPDU in response to the trigger frame; the trigger frame includes a common information field and one or more user information fields; At least one of the common information field and the user information field corresponding to the terminal among the one or more user information fields is used to identify whether the type of the TB PPDU is an extremely high throughput (EHT) type or a high efficiency (HE) type; the TB PPDU includes a length field associated with the length of the TB PPDU; The length field is set to a first value or a second value based on a length value included in the trigger frame, and the first value or the second value is a different value depending on whether the type of the PPDU is the HE type or the EHT type. Terminal.

2. The common information field includes an uplink (UL) length field, The length value is indicated by the UL Length field. The terminal of claim 1.

3. When the type of the TB PPDU is the HE type, the length field is set to the first value; The first value is configured to have the same value as the length value. The terminal of claim 1.

4. When the type of the TB PPDU is the EHT type, the length field is set to the second value; The second value is configured to have a value equal to the length value plus a specified value. The terminal of claim 1.

5. The specific value is 2 The terminal according to claim 4.

6. The second value is a multiple of 3 based on the specified value. The terminal according to claim 4.

7. The TB PPDU of the EHT type includes a PHY version identifier (ID) subfield indicating whether the PHY version of the TB PPDU is EHT; the trigger frame further includes a format identifier subfield; The PHY Version ID subfield is configured to have the same value as the Format Identifier subfield. The terminal of claim 1.

8. The trigger frame does not indicate both the EHT type TB PPDU transmission and the HE type TB PPDU transmission. The terminal of claim 1.

9. The common information field includes a first subfield indicating a PPDU format to be transmitted on a primary channel; The user information field includes a second subfield indicating the location of a resource unit (RU) allocated to the terminal. The terminal of claim 1.

10. The first subfield indicates transmission of the EHT-type PPDU or the HE-type PPDU in the primary channel of a 160 MHz band; The second subfield indicates whether the RU assigned by the user information field is located on the primary channel or a secondary channel. The terminal of claim 9.

11. 1. A method performed by a terminal in a wireless communication system, comprising: receiving a trigger frame from an access point (AP) instructing one or more terminals to transmit physical layer protocol data units (PPDUs); transmitting a trigger based (TB) PPDU in response to the trigger frame; the trigger frame includes a common information field and one or more user information fields; At least one of the common information field and the user information field corresponding to the terminal among the one or more user information fields is used to identify whether the type of the TB PPDU is an extremely high throughput (EHT) type or a high efficiency (HE) type; the TB PPDU includes a length field associated with the length of the TB PPDU; The length field is set to a first value or a second value based on a length value included in the trigger frame, and the first value or the second value is a different value depending on whether the type of the PPDU is the HE type or the EHT type. method.

12. The common information field includes an uplink (UL) length field; The length value is indicated by the UL Length field. The method of claim 11.

13. When the type of the TB PPDU is the HE type, the length field is set to the first value; The first value is configured to have the same value as the length value. The method of claim 11.

14. When the type of the TB PPDU is the EHT type, the length field is set to the second value; The second value is configured to have a value equal to the length value plus a specified value. The method of claim 11.

15. The specific value is 2 The method of claim 14.

16. The second value is a multiple of 3 based on the specified value. The method of claim 14.

17. The TB PPDU of the EHT type includes a PHY version identifier (ID) subfield indicating whether the PHY version of the TB PPDU is EHT; the trigger frame further includes a format identifier subfield; The PHY Version ID subfield is configured to have the same value as the Format Identifier subfield. The method of claim 11.

18. The trigger frame does not indicate both the EHT type TB PPDU transmission and the HE type TB PPDU transmission. The method of claim 11.

19. The common information field includes a first subfield indicating a PPDU format to be transmitted on a primary channel; The user information field includes a second subfield indicating the location of a resource unit (RU) allocated to the terminal. The method of claim 11.

20. The first subfield indicates transmission of the EHT-type PPDU or the HE-type PPDU in the primary channel of a 160 MHz band; The second subfield indicates whether the RU assigned by the user information field is located on the primary channel or a secondary channel.

20. The method of claim 19.

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