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

Abstract

To provide a method for receiving a PPDU in a wireless communication system.SOLUTION: A terminal receives, from an access point (AP), an extremely high throughput (EHT) physical layer protocol data unit (PPDU) comprising at least one EHT-signal (SIG) content channel. Each of the at least one EHT-SIG content channel comprises a user-specific field and a common field comprising at least one first resource unit (RU) allocation subfield. An STA then identifies whether the common field further comprises at least one second RU allocation subfield, and can decode the PPDU on the basis of whether the common field further comprises the at least one second RU allocation subfield.SELECTED DRAWING: Figure 22

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 ultra-high speed signaling field information in a wireless communication system. [Background technology]

[0002] Recently, as the use of mobile devices has become more widespread, wireless LAN technology that can provide them with high-speed wireless Internet services has been attracting attention. Wireless LAN technology is a technology that enables mobile devices such as smartphones, smart pads, laptop PCs, portable multimedia players, embedded devices, etc. to wirelessly connect to the Internet at home, in business, or in specific service areas based on short-distance wireless communication technology.

[0003] Since IEEE (Institute of Electronics Engineers) 802.11 supported the initial wireless LAN technology using the 2.4GHz frequency band, it has put into practical use or is currently developing various technology standards. First, IEEE 802.11b uses the 2.4GHz frequency band and supports a maximum communication speed of 11Mbps. IEEE 802.11a, which was commercialized after IEEE 802.11b, uses the 5GHz frequency band instead of the 2.4GHz band, reducing the impact of interference compared to the significantly more congested 2.4GHz frequency band, and uses OFDM technology to increase communication speeds to a maximum of 54Mbps. 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 satisfies backward compatibility, which has attracted considerable attention, but it also has an advantage over IEEE 802.11a in communication distance.

[0004] IEEE 802.11n is a technical standard established to overcome the communication speed limitations that have been pointed out as a weakness of wireless LAN. The purpose of IEEE 802.11n is to increase the speed and reliability of the network and to extend the operating distance of the wireless network. In detail, IEEE 802.11n supports a high throughput (HT) of up to 540Mbps or more in data processing speed, and is based on MIMO (Multiple Inputs and Multiple Outputs) technology that 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 the use of wireless LANs becomes more widespread and applications using them become more diverse, the need for new wireless LAN systems to support data throughput rates (Very High Throughput, VHT) higher than those supported by IEEE 802.11n is emerging. Among them, IEEE 802.11ac supports wide bandwidth (80MHz~160MHz) at 5GHz frequency. Although the IEEE 802.11ac standard is defined only in the 5GHz band, it is expected that initial 11ac chipsets will also support operation in the 2.4GHz band for backward compatibility with existing 2.4GHz band products. Theoretically, this standard allows multi-station wireless LAN speeds of at least 1Gbps and maximum single link speeds of at least 500Mbps. This is done by extending the air interface concepts accepted by 802.11n, such as wider radio frequency bandwidth (up to 160MHz), more MIMO spatial streams (up to 8), multi-user MIMO, and high density modulation (up to 256QAM). Also, 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, and is suitable for streaming large amounts of data and high bitrate videos such as uncompressed HD video. However, the 60GHz frequency band has the disadvantage that it is 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 in the final stages as the WLAN standard after 802.11ac and 802.11ad 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, it is necessary to provide high-frequency efficient communication indoors / outdoors in the presence of high density stations and APs (Access Points), and various technologies are being developed to realize this.

[0007] In addition, new WLAN standards have begun to be developed to increase maximum transmission speeds to support new multimedia applications such as high-definition video and real-time games. IEEE 802.11be (Extremely High Throughput, EHT), the 7th 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 multiple 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 transmitting information for receiving a PPDU.

[0010] Another object of the present invention is to provide a method for separately encoding / decoding a resource unit (RU) allocation subfield indicating the resource unit in which the PPDU is transmitted.

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

[0012] A terminal for transmitting a TB PPDU (Trigger Based Physical layer Protocol Data Unit), which is a response frame based on a trigger frame in a wireless communication system, includes a communication module; and a processor for controlling the communication module, wherein the processor receives an EHT PPDU (Physical layer Protocol Data Unit) including one or more EHT (Extremely High Throughput)-SIG (signal) content channels from an AP (Access Point), each of the one or more EHT-SIG content channels including a common field including at least one first resource unit (RU) allocation subfield and a user specific field, identifies whether the common field further includes at least one second RU allocation subfield, and decodes the PPDU based on whether the common field further includes at least one second RU allocation subfield.

[0013] In addition, in the present invention, when the common field further includes the at least one second RU allocation subfield, the at least one first RU allocation subfield and the at least one second RU allocation subfield are decoded separately.

[0014] Also, in the present invention, when the common field further includes the at least one 2nd RU allocation subfield, each of the one or more EHT-SIG content channels further includes a first CRC (cyclic redundancy check) and a first tail associated with the at least one 1st RU allocation subfield, and when the common field further includes the at least one 2nd RU allocation subfield, the first CRC and the first tail are located before the at least one 2nd RU allocation subfield, and each of the one or more EHT-SIG content channels further includes a second CRC and a second tail associated with the at least one 2nd RU allocation subfield.

[0015] In addition, in the present invention, whether each of the one or more EHT-SIG content channels further includes the at least one 2nd RU allocation subfield is identified based on a specific subfield located before the at least one 1st RU allocation subfield.

[0016] In addition, in the present invention, a specific subfield, the at least one first RU allocated subfield, the first CRC, and the first tail constitute a first encoding block, and the at least one second RU allocated subfield, the second CRC, and the second tail constitute a second encoding block.

[0017] In addition, in the present invention, the first encoding block and the second encoding block are decoded separately.

[0018] In addition, in the present invention, the one or more EHT-SIG content channels are each transmitted at a fixed bandwidth depending on the bandwidth of the PPDU, and the specific subfield is set to the same value for each of the one or more EHT-SIG content channels.

[0019] In addition, in the present invention, the specific subfield is used to identify the total number of each of the at least one first RU allocated subfield and the at least one second RU allocated subfield.

[0020] The present invention also provides a method including the steps of receiving an EHT Physical layer Protocol Data Unit (PPDU) including one or more EHT (Extremely High Throughput)-signal (EHT-SIG) content channels from an Access Point (AP), each of the one or more EHT-SIG content channels including a common field including at least one first Resource Unit (RU) allocation subfield and a User Specific field; identifying whether the common field further includes at least one second RU allocation subfield; and decoding the PPDU based on whether the common field further includes at least one second RU allocation subfield. Effect of the Invention

[0021] According to an embodiment of the present invention, ultra-high speed signaling field information can be efficiently signaled.

[0022] 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.

[0023] Also, according to the embodiment of the present invention, a PPDU can be received and decoded based on information for transmitting and receiving the PPDU included in the PPDU.

[0024] In addition, according to an embodiment of the present invention, the packet structure of the PPDU can be efficiently configured by individually encoding / decoding the RU allocation subfield indicating the RU for PPDU transmission.

[0025] 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 description of the drawings]

[0026] [Figure 1] FIG. 1 is a diagram showing a wireless LAN system according to an embodiment of the present invention. [Diagram 2] FIG. 11 is a diagram showing a wireless LAN system according to another embodiment of the present invention. [Diagram 3] FIG. 2 is a diagram showing a configuration of a station according to an embodiment of the present invention. [Figure 4] FIG. 2 is a diagram showing the configuration of an access point according to an embodiment of the present invention. [Diagram 5] 1 is a diagram illustrating a process in which a STA sets up 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 illustrates an embodiment of various standard generation PPDU (PLCP Protocol Data Unit) formats. [Figure 8] 1 illustrates an example of various EHT (Extremely High Throughput) PPDU formats and a method for indicating the same according to an embodiment of the present invention. [Figure 9] 1 shows an example of an EHT PPDU format according to an embodiment of the present invention. [Figure 10] 2 shows a preamble structure according to one embodiment of the present invention. [Figure 11]1 shows the configuration of an EHT-SIG field according to one embodiment of the present invention. [Figure 12A] 13 illustrates an example of a RU allocation subfield according to one embodiment of the present invention. [Figure 12B] 13 illustrates an example of a RU allocation subfield according to one embodiment of the present invention. [Figure 13A] 13 illustrates yet another example of an RU allocation subfield according to one embodiment of the present invention. [Figure 13B] 13 illustrates yet another example of an RU allocation subfield according to one embodiment of the present invention. [Figure 14] 1 shows an example of a structure of an EHT-SIG according to an embodiment of the present invention. [Figure 15] 1 illustrates yet another example of an EHT-SIG structure according to an embodiment of the present invention. [Figure 16] 1 shows an example of an EHT-SIG structure when the bandwidth of the PPDU in one embodiment of the present invention is 20 MHz or 40 MHz. [Figure 17] A diagram showing the EHT-SIG structure of an 80 MHz PPDU in one embodiment of the present invention. [Figure 18] 1 illustrates an example of center 26-tone RU signaling according to one embodiment of the present invention. [Figure 19] 13 shows yet another example of center 26-tone RU signaling in one embodiment of the present invention. [Figure 20] 13 shows yet another example of center 26-tone RU signaling in one embodiment of the present invention. [Figure 21] 1 illustrates yet another example of an EHT-SIG structure according to an embodiment of the present invention. [Figure 22] 1 is a flowchart illustrating an example of a method for receiving and decoding a PPDU according to an embodiment of the present invention. [Diagram 23] 1 is a flowchart illustrating an example of a method for generating and transmitting a PPDU according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] The terms used in this specification are selected as general terms that are currently widely used as much as possible in consideration of the functions of the present invention, but this may vary depending on the intentions, customs, or the emergence of new technologies of the engineers in the relevant technical field. In addition, in certain cases, the applicant may arbitrarily select terms, and in such cases, the meanings of the terms will be described in the description of the relevant invention. Therefore, it is clear that the terms used in this specification should be interpreted not simply as terms, but based on the substantial meanings of the terms and the contents of this specification as a whole.

[0028] Throughout the specification, when a component is "connected" to another component, this includes not only when it is "directly connected" to another component, but also when it is "electrically connected" with another component in between. Furthermore, when a component "includes" a specific component, this means that it may further include the other component, not excluding the other component, unless otherwise specified to the contrary. In addition, limitations such as "greater than" or "less than" based on a specific critical value may be appropriately replaced with "more than" or "less than" depending on the embodiment.

[0029] Hereinafter, in the present invention, the terms field and subfield may be used interchangeably.

[0030] FIG. 1 is a diagram showing a wireless LAN system according to an embodiment of the present invention.

[0031] A wireless LAN system includes one or more Basic Service Sets (BSS), which are a set of devices that can successfully synchronize and communicate with each other. Generally, BSSs are classified into infrastructure BSSs and independent BSSs (IBSSs), and Figure 1 shows an infrastructure BSS.

[0032] 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 which are stations providing a distribution service, and a distribution system DS which connects multiple access points AP-1 and AP-2.

[0033] A station (STA) is any device including a medium access control (MAC) and a physical layer interface for a wireless medium according to the IEEE 802.11 standard, and in a broad sense includes 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 further includes a user interface unit and a display unit, etc., depending on the embodiment. The processor generates frames to be transmitted through a wireless network, processes frames received through 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 through the wireless network for the station. In the present invention, the term "terminal" is used to include a user equipment (UE).

[0034] An access point (AP) is an entity that provides a connection to a distribution system DS via a wireless medium for a station associated therewith. In an infrastructure BSS, communication between non-AP stations is generally performed via the AP, but when a direct link is set up, direct communication is possible between non-AP stations. Meanwhile, in the present invention, AP is used as a concept including a personal BSS coordination point (PCP), but in a broad sense, AP includes all 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, AP is also referred to as a base wireless communication terminal, but in a broad sense, the 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 in communication with a plurality of wireless communication terminals.

[0035] A plurality of infrastructure BSSs are connected to each other via a distribution system DS. In this case, a plurality of BSSs connected to each other via the distribution system is called an Extended Service Set (ESS).

[0036] 2 is a diagram showing an independent BSS, which is a wireless LAN system according to another embodiment of the present invention, in which the same or corresponding parts in the embodiment of FIG. 2 are the same as or correspond to the embodiment of FIG.

[0037] BSS3 shown in Figure 2 is an independent BSS and does not include an AP, so all stations (STA6, STA7) are not 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.

[0038] 3 is a block diagram showing a configuration of a station 100 according to an embodiment of the present invention. As shown in the figure, 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.

[0039] First, the communication unit 120 transmits and receives wireless signals such as wireless LAN packets, and may be built into or externally provided in 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 of 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 of 7.125 GHz or more and a communication module using a frequency band of 7.125 GHz or less. Each communication module may perform wireless communication with an AP or an external station based on the wireless LAN standard of the frequency band supported by the communication module. The communication unit 120 may operate only one communication module at a time or operate multiple communication modules simultaneously according to the performance and requirements of the station 100. When the station 100 includes multiple communication modules, each communication module may be provided in an independent form, or multiple modules may be integrated into one chip. In an embodiment of the present invention, the communication unit 120 may represent a radio frequency (RF) communication module that processes RF signals.

[0040] 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 a command from the processor 110 using various output means.

[0041] Then, 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 or 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 connection programs required for the station 100 to connect to an AP or an external station.

[0042] 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 transmission and reception of data between the units. According to an embodiment of the present invention, the processor 110 executes a program for connection to an AP stored in the memory 160 and receives a communication setup message transmitted by the AP. The processor 110 also reads information on the priority conditions of the station 100 included in the communication setup message and requests a connection to the AP based on the information on the priority conditions of the station 100. The processor 110 of the present invention may refer to a main control unit of the station 100, or may refer to a control unit for individually controlling some components of the station 100, for example, the communication unit 120, depending on the embodiment. That is, the processor 110 may be a modem that modulates and demodulates a wireless signal transmitted and received from the communication unit 120, or a modulator and / or demodulator. The processor 110 controls various operations of transmitting and receiving wireless signals of the station 100 according to an embodiment of the present invention. A detailed embodiment of the present invention will be described later.

[0043] The station 100 shown in FIG. 3 is a block diagram according to an embodiment of the present invention, and the separate blocks are used to logically distinguish the elements of the device. Thus, the above-mentioned device elements may be mounted on one chip or multiple chips depending on the design of the device. For example, the processor 110 and the communication unit 120 may be integrated and embodied on one chip, or may be embodied on separate chips. In addition, in an embodiment 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.

[0044] 4 is a block diagram showing a configuration of an AP 200 according to an embodiment of the present invention. As shown in the figure, 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, a duplicated description 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.

[0045] 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 a plurality of communication modules using different frequency bands. That is, the AP 200 according to the embodiment of the present invention may include two or more communication modules using different frequency bands, for example, any of 2.4 GHz, 5 GHz, 6 GHz, and 60 GHz. Preferably, the AP 200 may include a communication module using a frequency band of 7.125 GHz or higher and a communication module using a frequency band of 7.125 GHz or lower. 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 operate multiple communication modules simultaneously according to the performance and requirements of the AP 200. In the embodiment of the present invention, the communication unit 220 may represent an RF communication module that processes RF (Radio Frequency) signals.

[0046] Next, the memory 260 stores control programs used in the AP 200 and various data associated therewith. Such control programs include a connection program for managing station connections. Also, the processor 210 controls each unit of the AP 200 and controls transmission and reception of data between the units. According to an embodiment of the present invention, the processor 210 executes a program for connection with a station stored in the memory 260 and transmits a communication setting message to one or more stations. At this time, the communication setting message includes information regarding connection priority conditions of each station. Also, the processor 210 performs connection setting in response to a connection request of a station. According to an embodiment, the processor 210 is a modem or a modulation / demodulation unit that modulates and demodulates wireless signals transmitted and received from the communication unit 220. The processor 210 controls various operations of transmitting and receiving wireless signals of the AP 200 according to an embodiment of the present invention. A detailed embodiment thereof will be described later.

[0047] FIG. 5 is a diagram illustrating a process in which a STA establishes a link with an AP.

[0048] 5, the link between the STA 100 and the AP 200 is set up through three steps: scanning, authentication, and association. First, the scanning step is a step in which the STA 100 acquires connection information of the BSS operated by the AP 200. There are two methods for performing scanning: 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.

[0049] The STA 100 that has successfully received wireless connection information in the scanning step transmits an authentication request (S107a), receives an authentication response from the AP 200 (S107b), and performs an authentication step. After the authentication step is performed, the STA 100 transmits an association request (S109a), receives an association response from the AP 200, and performs an association step (S109b). In this specification, association basically means wireless association, but the present invention is not limited thereto, and association in a broad sense includes both wireless association and wired association.

[0050] Meanwhile, an 802.1X-based authentication step S111 and an IP address acquisition step S113 via DHCP are additionally performed. In Fig. 5, the server 300 is a server that processes 802.1X-based authentication with the STA 100, and may be physically connected to the AP 200 or may exist as a separate server.

[0051] FIG. 6 is a diagram showing a Carrier Sense Multiple Access (CSMA) / Collision Avoidance (CA) method used in wireless LAN communication.

[0052] A terminal performing wireless LAN communication performs carrier sensing before transmitting data to check whether a channel is occupied or not. If a wireless signal of a certain strength or more 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 the signal is detected is called the CCA threshold. If a wireless signal of a strength greater than 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 of a strength less than the CCA threshold is detected, the channel is determined to be idle.

[0053] If the channel is determined to be in an idle state, each terminal having data to transmit performs a backoff procedure after an IFS (Inter Frame Space) time, 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 to replace 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 the slot time attempts to access the corresponding channel. The period in which each terminal performs a backoff procedure is called a contention window period.

[0054] If a specific terminal succeeds in accessing the channel, the terminal transmits data through 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 random numbers newly assigned to each terminal are determined within a range (2*CW) twice the range (contention window, CW) of the random numbers previously assigned to the terminal. Meanwhile, each terminal attempts access by performing a backoff procedure again in the next contention window period, and at this time, each terminal performs the backoff procedure from the slot time remaining in the previous contention window period. In this manner, each terminal performing wireless LAN communication can avoid collision with each other on a specific channel.

[0055] <Examples of various PPDU formats>

[0056] FIG. 7 shows an example of various standard generation PPDU (PLCP Protocol Data Unit) formats. More specifically, FIG. 7(a) shows an example of a legacy PPDU format based on 802.11a / g, FIG. 7(b) shows an example of a HE PPDU format based on 802.11ax, and FIG. 7(c) shows an example of a non-legacy PPDU (i.e., EHT PPDU) format based on 802.11be. FIG. 7(d) shows the detailed field configuration of L-SIG and RL-SIG commonly used in these PPDU formats.

[0057] 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.

[0058] Referring to FIG. 7(b), the preamble of the HE PPDU further includes, in addition to the legacy preamble, 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 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 be modified according to the HE PPDU format. For example, HE-SIG-B may be used only in the HE MU PPDU format.

[0059] Referring to FIG. 7(c), the preamble of the EHT PPDU further includes, in addition to the legacy preamble, RL-SIG (Repeated Legacy Short Training field), U-SIG (Universal Signal field), EHT-SIG-A (Extremely High Throughput Signal A field), EHT-SIG-A (Extremely High Throughput Signal B field), EHT-STF (Extremely High Throughput Short Training field), and EHT-LTF (Extremely High Throughput Long Training field). In an embodiment of the present invention, the RL-SIG, EHT-SIG-A, EHT-SIG-B, EHT-STF, and EHT-LTF can be called an EHT preamble. The specific configuration of the non-legacy preamble may be modified according to the EHT PPDU format. For example, EHT-SIG-A and EHT-SIG-B may be used only in some formats of the EHT PPDU format.

[0060] The L-SIG field included in the preamble of the PPDU is configured with a total of 64 subcarriers by applying 64FFT OFDM. Of these, 48 subcarriers excluding the guard subcarrier, DC subcarrier, and pilot subcarrier are used for data transmission of the L-SIG. Since BPSK and Rate=1 / 2 MCS (Modulation and Coding Scheme) are applied to the L-SIG, it can contain a total of 24 bits of information. Figure 7(d) shows the 24-bit information configuration of the L-SIG.

[0061] 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 / 54 Mbps, which are a combination of a modulation method such as BPSK / QPSK / 16-QAM / 64-QAM and a code rate such as 1 / 2, 2 / 3, or 3 / 4. The total length of the PPDU can be indicated by combining the information in the L_RATE field and the L_LENGTH field. In the non-legacy PPDU format, the L_RATE field is set to the minimum rate of 6 Mbps.

[0062] The unit of the L_LENGTH field is a byte, and a total of 12 bits are allocated to signal up to 4095, and the length can be indicated by combination with the L_RATE field. At this time, legacy terminals and non-legacy terminals can interpret the L_LENGTH field in different ways.

[0063] First, the method in which a legacy or non-legacy terminal interprets the length of the PPDU using the L_LENGTH field is 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 64 FFT. Therefore, the number of 64 FFT reference symbols after the L-SIG is obtained by adding 3 bytes corresponding to the SVC field and the Tail field to the L_LENGTH field value and dividing it by 3 bytes, which is the transmission amount of one symbol. The length of the PPDU, i.e., the reception time (RXTIME), is obtained by multiplying the obtained number of symbols by 4 us, which is one symbol duration, and adding 20 us for the transmission of the L-STF, L-LTF, and L-SIG. This can be expressed as the following Equation 1.

[0064] [Number 1]

number

[0065] At this time,

number

[0066] [Number 2]

number

[0067] 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.

[0068] [Number 3]

number

[0069] 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.

[0070] Referring to FIG. 7(e), the U-SIG (Universal SIG) field continues to exist in the EHT PPDU and the succeeding generation WLAN PPDU, and contains 11be to distinguish which generation of PPDU it is. The U-SIG is a 64FFT-based OFDM2 symbol and can transmit a total of 52 bits of information. Of these, 43 bits excluding the CRC / tail 9 bits are roughly divided into a VI (Version Independent) field and a VD (Version Dependent) field.

[0071] The VI bit will maintain the current bit configuration, and even if a subsequent generation PPDU is defined, the current 11be terminal can obtain information about the PPDU through the VI field of the PPDU. To this end, the VI field is composed of PHY version, UL / DL, BSS color, TXOP, and Reserved fields. The PHY version field is 3 bits long and serves to distinguish 11be and subsequent generation WLAN standards according to the version. In the case of 11be, it has a value of 000b. The UL / DL field distinguishes whether the corresponding PPDU is an uplink / downlink PPDU. The BSS color means a BSS-specific identifier defined in 11ax and has a value of 6 bits or more. The TXOP means the Transmit Opportunity Duration transmitted in the MAC header, but by adding it to the PHY header, the length of the TXOP containing the corresponding PPDU can be inferred without decoding the MPDU, and has a value of 7 bits or more.

[0072] The VD field is signaling information useful only for PPDUs of the 11be version, and may be composed of fields commonly used in all PPDU formats, such as the PPDU format and BW, and fields defined differently for each PPDU format. The PPDU format is a division factor that distinguishes EHT SU (Single User), EHT MU (Multiple User), EHT TB (Trigger-based), EHT ER (Extended Range) PPDU, etc. The BW field mainly signals five basic PPDU BW options of 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), and various remaining PPDU BWs formed by preamble puncturing. After 320 MHz is signaled, some 80 MHz may be signaled in a punctured form. Also, the punctured and modified channel shape may be directly signaled in the BW field, or may be signaled using the BW field together with a field that appears after the BW field (e.g., a field in the EHT-SIG field). If the BW field is 3 bits, a total of 8 BW signalings are possible, so the puncturing mode can only signal a maximum of 3. If the BW field is 4 bits, a total of 16 BW signalings are possible, so the puncturing mode can signal a maximum of 11.

[0073] The fields located after the BW field vary depending on the type and format of the PPDU. The MU PPDU and the SU PPDU may be signaled in the same PPDU format, and a field for distinguishing the MU PPDU from the SU PPDU may be located before the EHT-SIG field, and additional signaling may be performed for this purpose. Both the SU PPDU and the MU PPDU include an EHT-SIG field, but some fields that are not necessary in the SU PPDU may be compressed. In this case, the information of the compressed field may be omitted or may have a reduced size compared to the size of the original field included in the MU PPDU. For example, the SU PPDU may have other configurations, such as the common field of the EHT-SIG being omitted or replaced, or the user-specific field being replaced or reduced to one.

[0074] Alternatively, the SU PPDU may further include a compression field indicating whether or not compression is performed, and some fields (eg, the RA field, etc.) may be omitted depending on the value of the compression field.

[0075] When a part of the EHT-SIG field of the SU PPDU is compressed, information included in the compressed field may be signaled together in an uncompressed field (e.g., a common field, etc.). In the case of the 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 transmitted to itself. Therefore, the AP must transmit the above information including it 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 of the EHT-SIG field and / or MCS, which is a modulation method. The EHT-SIG field may include the size and location information of the RU assigned to each user.

[0076] In the case of SU PPDU, multiple RUs may be assigned to the STA, and the multiple RUs may be consecutive or discontinuous. If the RUs assigned to the STA are not consecutive, the STA can efficiently receive the SU PPDU only by recognizing the punctured RUs in between. Therefore, the AP can transmit the SU PPDU including information on the punctured RUs among the RUs assigned to the STA (e.g., the puncturing pattern of the RUs, etc.). That is, in the case of SU PPDU, a puncturing mode field including information indicating whether or not 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 may signal the type of discontinuous channels that appear within the bandwidth.

[0077] The form of the 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, in the case of a SU PPDU, since it is a PPDU transmitted only to a single UE, the STA can recognize the bandwidth allocated to itself by the BW field included in the PPDU, and can recognize the punctured resources among the allocated bandwidth by 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 except for the specific channel of the punctured resource unit. In this case, the multiple RUs allocated to the STA may be configured with different frequency bands or tones.

[0078] 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 for a BW having multiple 20 MHz subchannels such as 80, 160, and 320 MHz, in the case of 320 MHz, the discontinuous channel type (when the punctured type of only the edge 20 MHz is considered discontinuous) must be signaled by expressing the use or non-use of the remaining 15 20 MHz subchannels excluding the primary channel. In this way, allocating 15 bits to signal the discontinuous channel type of single user transmission may act as an excessively large signaling overhead when considering the low transmission speed of the signaling part.

[0079] In addition, in one embodiment of the present invention, a method is proposed in which the configuration of the PPDU indicated by the preamble puncturing BW value is different 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, one symbol of EHT-SIG-A may be further signaled after the U-SIG, or EHT-SIG-A may not be signaled at all. Taking this into consideration, it is necessary to signal up to 11 puncturing modes only through the BW field of the U-SIG. However, in the case of an EHT MU PPDU, since EHT-SIG-B is further signaled after the U-SIG, up to 11 puncturing modes can be signaled in a different manner from the SU PPDU. In the case of an EHT ER PPDU, the BW field is set to 1 bit, and a PPDU using a 20 MHz or 10 MHz band can be signaled.

[0080] FIG. 7(f) is a diagram showing the configuration of the format-specific field of the VD field when the PPDU format field of the U-SIG indicates EHT MU PPDU. In the case of MU PPDU, SIG-B, which is a signaling field for simultaneous reception by multiple users, is required, and SIG-B may be transmitted after U-SIG without a separate SIG-A. For this purpose, U-SIG must signal information for decoding SIG-B. Such fields include SIG-B MCS, SIG-B DCM, Number of SIG-B Symbols, SIG-B Compression, and Number of EHT-LTF Symbols.

[0081] FIG. 8 illustrates an example of various Extremely High Throughput (EHT) PPDU formats and a method for indicating the same according to an embodiment of the present invention.

[0082] 8, a PPDU may be composed of a preamble and a data portion, and the format of an EHT PPDU, which is one type, may be distinguished by a U-SIG field included in the preamble. Specifically, whether the format of the PPDU is an EHT PPDU may be indicated based on a PPDU format field included in the U-SIG field.

[0083] 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.

[0084] 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.

[0085] 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.

[0086] Fig. 8(d) shows an example of an EHT ER SU PPDU format used for single-user transmission with an STA in an extended range. The EHT ER SU PPDU may be used for single-user transmission with a STA in a wider range than the EHT SU PPDU described in Fig. 8(a), and the U-SIG field may be repeatedly positioned on the time axis.

[0087] The EHT MU PPDU described in (c) of FIG. 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 STAs by 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.

[0088] Specifically, the resource unit allocation (RA) field of the HE-SIG-B field included in the HE MU PPDU may include information regarding a resource unit configuration (e.g., a resource unit division form) in a specific bandwidth (e.g., 20 MHz, etc.) on the frequency axis. That is, the RA field may indicate a resource unit configuration divided by a bandwidth for transmitting the HE MU PPDU so that the STA can receive the PPDU. Information on 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.

[0089] For example, a user field corresponding to at least one resource unit used for data transmission among the multiple divided resource units may include the AID of a receiver or sender, and a user field corresponding to the remaining resource units not used for data transmission may include a null STA ID that has already been set.

[0090] 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 using the same value. For example, EHT SU PPDU and EHT MU PPDU can be indicated by the same value by the U-SIG PPDU format subfield. In this case, EHT SU PPDU and EHT MU PPDU can be distinguished according to the number of STAs receiving the PPDU. For example, a PPDU received by only one STA can be identified as an EHT SU PPDU, and when the number of STAs is set so that two or more STAs receive the PPDU, it can be identified as an EHT MU PPDU. In other words, two or more PPDU formats shown in FIG. 8 can be indicated by using the same subfield value.

[0091] In addition, some fields or some information of the fields may be omitted from the fields shown in FIG. 8, and such a case where some fields or some information of the fields is omitted can be defined as a compression mode or compressed mode.

[0092] FIG. 9 shows an example of an EHT PPDU format according to an embodiment of the present invention.

[0093] 9, the EHT PPDU may include one or more signaling fields (SIG fields). Specifically, the EHT PPDU may include an L-SIG field, a U-SIG field, an EHT-SIG field, etc., as described in FIG. 7 and FIG. 8, and the EHT-SIG field may include an EHT-SIG-A field and / or an EHT-SIG-B field.

[0094] The EHT PPDU may be composed of a preamble and data, and the preamble may include at least one of L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, EHT-SIG, EHT-STF, and EHT-LTF. Thus, the EHT preamble may be used to indicate one or more of the above fields. The positions and order of the fields included in the preamble may be the same as the order of the fields in FIG. 9 and mentioned above.

[0095] The L-STF, L-LTF and L-SIG may be fields for legacy compatibility, and the RL-SIG and the L-SIG may contain the same information, i.e., some or all bit values ​​of the L-SIG may be repeatedly set in the RL-SIG, and the RL-SIG may be used to distinguish the format of the PPDU.

[0096] The EHT-SIG may include a common field and a user specific field, and may include resource allocation information for transmitting a PPDU, STA information for identifying a STA to which resources are allocated, etc. Therefore, a STA receiving a PPDU can determine (or recognize) whether resources are allocated to it based on the EHT-SIG, and can determine how resources are allocated, such as the location and size of the allocated resources.

[0097] The common field may include resource unit (RU) allocation information for a resource unit (RU) allocated to at least one STA. For example, the RU allocation information may include information regarding the size, location, and configuration of resources allocated to the STA, the number of STAs to which the RU is allocated, etc.

[0098] The user specific field may include information (e.g., information about each STA) for a STA (user) receiving the PPDU to decode the payload, and may include information about one or more STAs. Specifically, the user specific field may include information about the STA to which the RU is assigned (e.g., STA ID (Station identifier), etc.) in individual fields corresponding to each STA. That is, information corresponding to STA1 (user1), information corresponding to STA2 (user2), information corresponding to STA3 (user3), ..., information corresponding to STA N (user N) may be consecutively included in the user specific field. In this case, information about each STA may be included in a user field, and user fields including information about each STA may be consecutively included in the user specific field.

[0099] A STA receiving a PPDU can determine whether an RU for receiving the PPDU is assigned based on whether a STA ID corresponding to the STA is included among the STA IDs in the user field included in the user specific field. That is, a STA can determine whether an RU is assigned to the STA by determining whether the STA ID corresponding to the RU assigned by the RU assignment subfield is its own ID, and can receive the PPDU through the RU assigned to the STA.

[0100] In addition, the information on the STA included in the user field may include information on the number of space-time streams (NSTS), information on whether a beamforming steering matrix is ​​applied (beamformed), information on the modulation and coding scheme (MCS), information on whether dual carrier modulation (DCM) is used, information on the coding method (e.g., information on which coding method (e.g., BCC or LDPC) is used), etc. In addition, such information may be information applied to the STA-ID value.

[0101] When the common field indicates the structure of the RU assigned to each STA and the number of STAs assigned to each RU, the user fields included in the user specific field may be mapped to the RUs indicated by the common field in the order of their positions. For example, RU1 may be assigned to one STA, RU2 to two STAs, and RU3 to one STA according to the RU assignment subfield of the common field, and the user specific field may sequentially include four user fields (user field 1, user field 2, user field 3, and user field 4). In this case, STAs corresponding to the STA IDs included in user field 1 may be assigned RU1, and STAs corresponding to the STA IDs included in user field 2 and user field 3 may be assigned RU2. Similarly, STAs corresponding to the STA IDs included in user field 4 may be assigned RU3. When two or more STAs are assigned to one RU, such as RU2, MIMO may be used.

[0102] The common fields and the user-specific fields may be included in the EHT-SIG in the order shown in FIG.

[0103] Hereinafter, in the present invention, the terms "field" and "subfield" may be used interchangeably, and are not limited to these names.

[0104] The EHT PPDU may further include a location indicator subfield, which may be included in the common field of the EHT-SIG as shown in Figure 9. The location indicator subfield may be referred to as a header field and may be used to indicate the location and number of RU allocation subfields in the common field.

[0105] Specifically, since the locator subfield may serve to indicate a position corresponding to the RU allocation subfield, the position of the RU indicated by the user field may be determined based on the locator subfield in addition to the RU allocation subfield. For example, the locator subfield may indicate the start position of the RU indicated by the RU allocation subfield and / or the position of the last assigned RU, and may indicate the number of RU allocation subfields. In this case, the RU allocation subfield refers to a field included in the common field of the EHT-SIG described above.

[0106] The locator subfield may be composed of a number of bits, and each of the bits may correspond to a band of a certain unit on the frequency axis. For example, each of the bits constituting the locator subfield may be mapped to a non-overlapping band. That is, each of the bits of the locator subfield may be mapped to each of the 20 MHz subbands, and at this time, each bit may be mapped sequentially according to the frequency order of the 20 MHz subbands. In other words, the locator subfield may be mapped to each of the bits of the locator subfield sequentially according to the frequency order of the band of a certain size unit.

[0107] For example, each bit may be mapped sequentially in frequency order to the Primary 20 MHz (P20), Secondary 20 MHz (S20), the first 20 MHz of Secondary 40 MHz (S40), the second 20 MHz of S40, the first 20 MHz of Secondary 80 (S80), the second 20 MHz of S80, the third 20 MHz of S80, the fourth 20 MHz of S80, the first 20 MHz of S160 (the band excluding P80 and S80 can be referred to as S160), the second 20 MHz of Secondary 160 MHz (S160), the third 20 MHz of S160, the fourth 20 MHz of S160, the fifth 20 MHz of S160, the sixth 20 MHz of S160, the seventh 20 MHz of S160, and the eighth 20 MHz of S160 bands.

[0108] For example, when a specific bit constituting the locator subfield is 1, the RU allocation subfield associated with the band mapped to the specific bit may be included in the common field. Also, when a specific bit constituting the locator subfield is 0, the RU allocation subfield associated with the band mapped to the specific bit may not be included in the common field. Therefore, the number of RU allocation subfields included in the common field may be determined based on the value of each bit of the locator subfield.

[0109] Therefore, the number of RU allocation subfields in the common field may be identified based on the particular field located before the RU allocation subfield.

[0110] The length (or size) of the locator subfield may be based on the bandwidth or channel width of the PPDU. In this case, the bandwidth or channel width may be indicated by a bandwidth field included in the U-SIG field, and may mean the bandwidth or channel width occupied by the PPDU including the U-SIG field of the bandwidth field.

[0111] For example, the length of the locator subfield may be 4 bits, 8 bits, or 16 bits, where the bandwidth is 80 MHz, 160 MHz, or 320 MHz, respectively.

[0112] Also, the length of the locator subfield may be based on puncturing information indicated by the U-SIG field. In this case, the puncturing information may be indicated by the bandwidth field of the U-SIG field. For example, when the bandwidth occupied by the PPDU is indicated by the bandwidth field, the puncturing information may also be indicated. That is, when the bandwidth of the PPDU is indicated by the bandwidth field, puncturing information indicating whether or not the indicated bandwidth is punctured may also be indicated.

[0113] For example, the locator subfield may not include bits for punctured channels (bands) that indicate the puncturing information, but may include bits for non-punctured channels (bands) that the puncturing information indicates, i.e., the locator subfield may include bits associated with non-punctured channels (bands).

[0114] Also, according to an embodiment of the present invention, the length and value of the locator subfield may be different for each band, for example, the length and value of the locator subfield included in the PPDU of P160 may be different from that of the PPDU of S160.

[0115] That is, depending on the bandwidth of the PPDU, the EHT-SIG field (or EHT-SIG content channel) of the PPDU may be repeatedly transmitted for each bandwidth unit channel (e.g., 20 MHz) within the bandwidth of the PPDU. In this case, the values ​​of the fields included in the U-SIG field of the PPDU may be set to the same value for each bandwidth unit channel, and some of the fields included in the EHT-SIG field may be set to the same value, and the remaining fields may be set to the same value or different values ​​individually.

[0116] For example, when the bandwidth of the PPDU is 80 MHz, the EHT-SIG field (or EHT-SIG content channel) may be repeated (or duplicated) a total of four times in 20 MHz units and transmitted. In this case, some of the fields of the EHT-SIG field may be set to the same value for each of the four channels in 20 MHz units, and the remaining fields may be set to the same or different values ​​individually. In this case, the locator subfield may be set to the same or different values ​​in each 20 MHz channel. That is, the value of some or all of the bits of the locator subfield may be set to the same or different values ​​between the EHT-SIG fields in each 20 MHz channel. However, the length and value of the locator subfield transmitted in the primary 80 and the secondary 80 may be different from each other.

[0117] As shown in Fig. 9, the common field included in the EHT-SIG field may include a locator subfield, and the locator subfield may be located before the RU allocation subfield. For example, the locator subfield may be included at the very beginning of the common field.

[0118] Also, the EHT-SIG of the EHT PPDU may include an RU assignment subfield. The RU assignment subfield may indicate the configuration and location of the assigned RU and the number of STAs (or users) assigned to each RU, as described above. Therefore, the number of user fields included in the user specific field may be determined by the RU assignment subfield. That is, since the user field includes information of the STA to which the RU is assigned, the number of user fields included in the user specific field may be identified by the RU assignment subfield according to the number of STAs to which the RU is assigned.

[0119] The number of RU allocation subfields included in the EHT PPDU may be determined based on a specific field. Specifically, the number of RU allocation subfields included in the EHT PPDU may be based on a locator subfield. For example, the number of RU allocation subfields may be based on the number of 1s in the bits of the locator subfield. That is, there may be N RU allocation subfields of unit length. Also, N may be based on the locator subfield, and N may be 0 in a compressed mode.

[0120] Thus, the number and / or positions of the RU allocation subfields may be identified by the locator subfield, and the size and value of the locator subfield may be identified by the bandwidth according to the bandwidth field of the U-SIG field. That is, the size and value of the locator subfield may be determined based on the bandwidth field of the U-SIG field, and the number and / or positions of the RU allocation subfields may be identified by the locator subfield. That is, the number of RU allocation subfields may be determined by the bandwidth field of the U-SIG field.

[0121] The EHT-SIG field may include a cyclic redundancy code (CRC) subfield and a tail subfield. The CRC included in the EHT-SIG field may be calculated for the locator subfield and the RU allocation subfield. The tail subfield may be used to complete the trellis of a convolutional decoder. The tail subfield may be used to flush the convolutional decoder. A receiver or decoder may need to decode a subfield corresponding to the CRC together with the CRC. For this reason, decoding is possible only if the subfield corresponding to the CRC has already been set.

[0122] As described above, the common fields included in the EHT-SIG field may include a locator subfield, a RU allocation subfield, a CRC, and a tail.

[0123] FIG. 10 shows a preamble structure according to an embodiment of the present invention.

[0124] According to an embodiment of the present invention, the U-SIG field or the EHT-SIG field may have different values ​​for each component band. For example, the component band may be an 80 MHz band or a 160 MHz band. Referring to FIG. 10, the EHT-SIG field may be different for each 80 MHz sub-band. In the embodiment of FIG. 10, the bandwidth of the PPDU is 320 MHz, and the 80 MHz sub-band 1, the 80 MHz sub-band 2, the 80 MHz sub-band 3, and the 80 MHz sub-band 4 include EHT-SIG1, EHT-SIG2, EHT-SIG3, and EHT-SIG4, respectively. Also, the receiver of the PPDU can receive the PPDU by decoding only the U-SIG field and the EHT-SIG field of a specific 80 MHz.

[0125] Also, the EHT-SIG field of the component band may have multiple content channels (CCs). Different content channels may mean having different common field values, different RU allocation subfield values, and / or different locator subfield values. For example, there may be two content channels. Referring to FIG. 10, each EHT-SIG field of the 80 MHz subband may have CC1 and CC2. That is, the multiple content channels of the EHT-SIG field may include subfields having the same value between content channels and / or subfields having different values ​​between channels.

[0126] For example, some fields in the common fields of the EHT-SIG content channels may have the same value between the content channels, and the remaining fields (e.g., RU allocation subfields, user specific subfields, etc.) may have different values ​​between the content channels. In this case, some or all of the bits of the locator subfield may have the same or different values ​​between the content channels depending on the role. For example, when some bits of the locator subfield play the role of a Center 26-tone RU subfield, such some bits may have the same value between the content channels.

[0127] In this case, specific subfields having the same value between each EHT-SIG content channel in the common field of the EHT-SIG field may be as follows.

[0128] - Spatial Reuse

[0129] - LDPC Extra Symbol Segment

[0130] - GI+LTF size

[0131] - Number of EHT-LTF symbols

[0132] - Pre-FEC padding factor

[0133] - PE Disambiguity

[0134] FIG. 11 shows the configuration of an EHT-SIG field according to one embodiment of the present invention.

[0135] FIG. 11 illustrates the use of the locator subfield and the RU allocation subfield described in FIG. 9 and the EHT-SIG field configuration, and the above content may be omitted.

[0136] As described above, each bit of the locator subfield may correspond to a previously set band. For example, each bit of the locator subfield may correspond to a 20 MHz subband. In this case, each bit of the locator subfield may indicate the 20 MHz subbands in sequence from the lowest frequency. FIG. 11 shows an example for a 320 MHz band. Referring to FIG. 11, the locator subfield may be composed of bits indicated as B0 to B15. Also, each bit may correspond to a 20 MHz subband, and B0 to B15 may indicate a total of 320 MHz band.

[0137] Also, the locator subfield may indicate the position of the RU to be signaled in the corresponding content channel. Or, the locator subfield may indicate the position corresponding to the RU allocation subfield to be signaled in the corresponding content channel. Referring to FIG. 11, the locator subfield may indicate RU1, RU3, and RU4 in the content channel 1, and RU2, RU5, RU6, and RU7 in the content channel 2. The locator subfield of the content channel 1 indicates the start positions of RU1, RU3, and RU4, and the locator subfield of the content channel 2 indicates the start positions of RU2, RU5, RU6, and RU7. In the locator subfield, a value of 1 may indicate the start of a band corresponding to the RU allocation subfield to be signaled. Therefore, in order to indicate the presence of the RU allocation subfield corresponding to RU3, which is an RU in the band corresponding to B2 to B7, B2 in the locator subfield of the content channel 1 is indicated as 1. Also, RU4 may use multiple RUs. RU4 may use both the band corresponding to B8 and the bands corresponding to B10 to B11. To indicate this, B8 of the position indicator subfield can be set to 1.

[0138] As explained, the location indicator subfield may indicate the band location corresponding to the RU allocation, and the actual size of the RU may be indicated in the RU allocation subfield.

[0139] 11, since the locator subfield of the content channel 1 indicates the positions and presence of RU1, RU3, and RU4, RU allocation subfields corresponding to RU1, RU3, and RU4 may exist, and the positions where the RU allocation subfields exist may be the content channel 1. Similarly, since the locator subfield of the content channel 2 indicates the positions and presence of RU2, RU5, RU6, and RU7, RU allocation subfields corresponding to RU2, RU5, RU6, and RU7 may exist, and the positions where the RU allocation subfields exist may be the content channel 2. Also, the RU allocation subfields may exist in the order of the RU allocation subfields indicated by the locator subfield. That is, the locator subfield may indicate the presence of an RU allocation subfield. For example, when a bit value of the locator subfield indicates the presence of an RU allocation subfield, bits with a value of 1 in the locator subfield may be sequentially mapped to the RU allocation subfields. That is, the first RU allocation subfield may correspond to the first bit in the locator subfield that is 1, and the second RU allocation subfield may correspond to the second bit in the locator subfield that is 1. Referring to Fig. 11, in content channel 1, the RU allocation subfield corresponding to B0, which is the first 1 in the locator subfield, may appear first, the RU allocation subfield corresponding to B2, which is the second 1 in the locator subfield, may appear second, and the RU allocation subfield corresponding to B8, which is the third 1 in the locator subfield, may appear third.

[0140] Therefore, the number of bits in the locator subfield whose bit value is 1 may indicate the number of RU allocation subfields. Alternatively, a value based on the number of bits in the locator subfield whose bit value is 1 may indicate the number of RU allocation subfields. In this case, the length of each RU allocation subfield may be N_RA bits.

[0141] Content channel 1 and content channel 2 shown in Fig. 11 may be CC1 and CC2 in a component band as shown in Fig. 10. Alternatively, content channel 1 and content channel 2 shown in Fig. 11 may indicate different EHT-SIGs for each component band as shown in Fig. 10 as EHT-SIG1 and EHT-SIG2.

[0142] Using RU signaling based on the locator subfield allows free signaling in any content channel, more specifically, it is possible to signal an RU in any position in any content channel.

[0143] In addition, after the locator subfield and the RU allocation subfield, a CRC and a tail may be present. In this case, the CRC may correspond to the locator subfield and the RU allocation subfield. That is, the locator subfield, the RU allocation subfield, and the CRC may be decoded together.

[0144] However, according to the embodiment of the present invention, since the number of RU allocation subfields is variable and the number of RU allocation subfields is determined based on the locator subfield value, it is difficult to determine the length of the bit sequence to be decoded together with the CRC. That is, it may be difficult to determine the lengths of the locator subfield and the RU allocation subfield used in the CRC calculation. Alternatively, the STA needs to decode together with the CRC to check the value of the locator subfield, but the length of the RU allocation subfield that is CRC-calculated together is unknown, making it difficult for the STA to decode.

[0145] 12A and 12B show an example of an RU allocation subfield according to one embodiment of the present invention.

[0146] Figures 12A and 12B are diagrams showing possible values ​​of the RU allocation subfield and RU configurations described in Figures 9 to 11. 26, 52, 106, 78, and 132 shown in Figures 12A and 12B may be the number of tones used by the RU. Each bit value of the RU allocation subfield may correspond to each value of a specific row in Figures 12A and 12B, and each RU may be allocated to a STA according to the configuration (or structure) of the RU according to the row.

[0147] The STAs to which each RU is assigned according to the RU assignment subfield may be identified by a user field located after the RU assignment subfield of the common field. That is, when the configuration of RUs assigned to STAs and the number of STAs using each RU are set by each bit of the RU assignment subfield, the STAs to which each RU is assigned may be identified by a user field included in the user specific field located after the RU assignment subfield.

[0148] For example, when the RU allocation subfield is set to the value in the first column (B9:0, B8...B0:0) of Figure 12A, nine 26-tone RUs may be allocated. In this case, a user field for identifying the STA corresponding to each 26-tone RU may be included and positioned in the user specific field.

[0149] In yet another embodiment of the present invention, an RU smaller than 242-tone RU may be referred to as a small RU or small-size RU. Also, an RU of 242-tone RU or larger may be referred to as a large RU or large-size RU. Figures 12A and 12B are examples showing RU allocation values ​​corresponding to small-size RUs, and the RU allocation subfield may also indicate large-size RUs as shown in Figures 13A and 13B.

[0150] 13A and 13B show yet another example of the RU allocation subfield according to one embodiment of the present invention.

[0151] 13A and 13B are diagrams showing possible values ​​of the RU allocation subfield and RU configurations described in FIG. 9 to FIG. 11, similarly to FIG. 12A and FIG. 12B. 242, 484, 996, 996x2, etc. shown in FIG. 13A and FIG. 13B may be the number of tones used by the RU. A certain value of the RU allocation subfield may correspond to a certain column of FIG. 13A and FIG. 13B, and the RU of the structure indicated by that column may be allocated to the STA. A user field corresponding to the RU indicated by the RU allocation subfield may be present after the RU allocation subfield. For example, when the RU allocation subfield indicates the value of the first column (B9:1, B8...B0:00000y3y2y1y0) of FIG. 13A, a structure in which 242-tone RUs are allocated may be present. In this case, a user field corresponding to the 242-tone RU may be present after. In addition, the columns shown in FIG. 13A and FIG. 13B do not need to be further divided into users by OFDMA. That is, for example, when the RU allocation subfield indicates the value of the fifth column (B9:1, B8...B0:00100y3y2y1y0) in Figures 13A and 13B, 242 and 484 tones are shown, but both 242 and 484 tones may be allocated to one user. Also, other STAs may be allocated to the same RU by MIMO.

[0152] Also, as an embodiment, an RU smaller than 242 tone RU may be referred to as a small RU or small size RU. Also, an RU of 242 tone RU or larger may be referred to as a large RU or large size RU. Figures 13A and 13B are examples showing RU allocation values ​​corresponding to large size RUs, and the RU allocation subfield may also indicate small size RUs as shown in Figures 12A and 12B.

[0153] FIG. 14 is a diagram showing an EHT-SIG structure according to one embodiment of the present invention.

[0154] The embodiment of FIG. 14 is a method for solving the problem described with reference to FIG. 11, and the same content as that described above may be omitted.

[0155] According to an embodiment of the present invention, the locator subfield may have an EHT-SIG structure that can be decoded independently of the RU allocation subfield. For example, a CRC and tail corresponding to the locator subfield and a CRC and tail corresponding to the RU allocation subfield may exist separately. Referring to FIG. 14, the EHT-SIG field or the common field may include a locator subfield, a CRC, a tail, an RU allocation subfield, a CRC, and a tail in this order. That is, the CRC corresponding to the locator subfield may exist before the RU allocation subfield. That is, the CRC corresponding to the locator subfield may correspond to bits from B0 of the EHT-SIG to the number of bits (e.g., 4, 8, or 16) of the locator subfield.

[0156] In addition, the CRC corresponding to the RU allocation subfield may correspond to the locator subfield, the CRC, and bits after the tail, numbered (number of bits in the RU allocation subfield) * (number of RU allocation subfields).

[0157] Therefore, the receiver or decoder may first decode the locator subfield value along with the corresponding CRC, then determine the number of RU allocation subfields, and decode the RU allocation subfield along with the corresponding CRC. More specifically, the length of the locator subfield may be determined based on the bandwidth value indicated by the U-SIG field. That is, as described above, the length of the locator subfield may be determined based on the bandwidth of the PPDU indicated by the bandwidth field of the U-SIG field. Thus, the locator subfield may be decoded along with the corresponding CRC. Also, the number of RU allocation subfields may be identified based on the decoded locator subfield value, and the RU allocation subfield may be decoded along with the corresponding CRC.

[0158] According to another embodiment of the present invention, the number of RU allocation subfields may be indicated by a field (e.g., a U-SIG field) before the EHT-SIG field. In this case, it is possible to decode the structure described in FIG. 9. That is, even if a CRC is calculated based on a locator subfield and a RU allocation subfield, the length of the RU allocation subfield is known, so decoding is possible. For example, if the number of RU allocation fields can be identified by a bandwidth field of a U-SIG field located before the EHT-SIG, the length of the RU allocation subfield is known by the bandwidth field, so the RU allocation field can be decoded even if a CRC is calculated based on the RU allocation subfield.

[0159] However, when free signaling is possible by signaling based on the locator subfield, the number of RU allocation subfields may also differ for each subband (e.g., 20 MHz band), and indicating all of them in the U-SIG field may result in a large signaling overhead. Therefore, according to one embodiment, it is possible to set the number of RU allocation subfields for each subband to be the same. For example, the maximum number of RU allocation subfields actually signaled in each subband may be indicated in the U-SIG field, and a dummy RU allocation subfield may be inserted for a subband with a number smaller than the maximum number.

[0160] According to another embodiment, the number of RU allocation subfields indicated by the U-SIG may be distributed to each content channel in the same number. However, if the number of RU allocation subfields indicated by the U-SIG is not divisible by the number of content channels, the number of RU allocation subfields distributed to each content channel may be divided so that the difference is 1 or less.

[0161] FIG. 15 illustrates yet another example of an EHT-SIG structure according to an embodiment of the present invention.

[0162] Referring to FIG. 15, the common field may be divided into each encoding block according to an encoding method, and each encoding block may include an RU allocation subfield. In this case, the number of encoding blocks may be one or more according to the bandwidth indicated in the bandwidth field of the U-SIG field, and each encoding block may be encoded separately. Therefore, the STA can decode the encoding blocks separately.

[0163] Specifically, the embodiment of Fig. 15 is for solving the problem described in Fig. 11 and may be an extension of the embodiment of Fig. 14. Therefore, the same content as described above may be omitted.

[0164] In the embodiment of Fig. 14, only the locator subfield can be used for CRC calculation, and the number of bits of the CRC and tail can be larger than the number of bits of the locator subfield, which means that redundancy is high.

[0165] Therefore, according to an embodiment of the present invention, the locator subfield and a pre-set number of RU allocation subfields can be used for CRC calculation. Also, there may be a separate CRC for RU allocation subfields other than the pre-set number of RU allocation subfields. Therefore, referring to FIG. 15, the EHT-SIG field or the common field may be divided into a first encoding block and a second encoding block based on the unit of the field to be encoded. In this case, the fields included in each encoding block may be encoded together, and the different encoding blocks may be encoded separately. Therefore, the STA receiving the PPDU may decode each encoding block separately according to the encoding block.

[0166] As shown in Figure 15, the first encoding block may include a locator subfield, a previously set number of RU allocation subfields (at least one first RU allocation subfield), a CRC (first CRC), and a tail (first tail), which may be encoded together, and the second encoding block may include the remaining RU allocation subfields (at least one second RU allocation subfield), a CRC (second CRC), and a tail (second tail), which may be encoded together in this order. Figure 15 shows the case where the previously set number is 1.

[0167] Therefore, the receiver or decoder can sequentially decode each encoding block. Specifically, the receiver or decoder can first decode the values ​​of the locator subfield and the pre-set number of RU allocation subfields included in the first encoding block together with the subsequent CRC, and then determine the number N of RU allocation subfields. If N is equal to or less than the pre-set number, the RU allocation subfield has already been signaled, and therefore the subsequent RU allocation subfield, CRC, and tail do not need to be further present.

[0168] If N is greater than the preset number, there may be further (N-(the preset number)) RU allocation subfields, a CRC, and a tail. Thus, after decoding the first encoding block, the receiver or decoder can decode the (N-(the preset number)) RU allocation subfields included in the second encoding block along with the subsequent CRC.

[0169] If N is 0, the RU assignment subfield already signaled may be dummy data, and the following RU assignment subfield, CRC, and tail may not be present. Therefore, the receiver may ignore the dummy data, and the following user field may not be present.

[0170] In the example indicated as RU1 (1 STA), RU2 (2 STAs), and RU3 (1 STA), the user specific fields may sequentially include user field 1, user field 2, user field 3, and user field 4. In this case, user field 1 may correspond to RU1, user field 2 may correspond to RU2, user field 3 may correspond to RU2, and user field 4 may correspond to RU3. In addition, when multiple users are assigned to the same RU, such as RU2 (2 STAs), MIMO may be used.

[0171] In this case, the number of encoding blocks may vary depending on the bandwidth of the PPDU indicated by the bandwidth field of the U-SIG field. For example, when the bandwidth of the PPDU indicated by the bandwidth field is 20, 40, or 80 MHz, only one or two RU allocation subfields are required, so only one encoding block may be included in the common field. In this case, one RU allocation subfield may be included when the indicated bandwidth is 20 or 40 MHz, and two RU allocation subfields may be included when the indicated bandwidth is 80 MHz.

[0172] The number of RU allocation subfields according to bandwidth indicated by the bandwidth field may mean the number of RU allocation subfields included in each EHT-SIG content channel.

[0173] In this case, since the common field of the EHT-SIG field contains one encoding block, the values ​​of the locator subfield and the already set number of RU allocation subfields may be decoded together with the following CRC.

[0174] However, when the bandwidth of the PPDU indicated by the bandwidth field is 160 MHz or more (e.g., 160 MHz or 320 MHz), the number of RU allocation subfields is three or more, and therefore, two encoding blocks may be included in the common field. In this case, the first encoding block and the second encoding block are encoded and / or decoded separately, and therefore, each encoding block may include a CRC and a tail separately.

[0175] As described above, the first encoding block may include a locator subfield, at least one RU allocation subfield, a CRC and a tail, and the second encoding block may include at least one RU allocation subfield, a CRC and a tail.

[0176] In this case, the first encoding block may further include a spatial reuse subfield indicating whether spatial reuse is used, a GI+LTF size subfield indicating the GI duration and the size of the EHT-LTF, a Number Of EHT LTF symbol indicating the number of EHT-LTF symbols, an LDPC extra symbol sequence subfield indicating whether an LDPC extra symbol sequence is present, a Pre-FEC Padding Factor subfield indicating a pre-FEC padding factor, and a PE Disambiguity subfield indicating PE disambiguity, which may be encoded / decoded together.

[0177] 16 shows an example of an EHT-SIG structure when the bandwidth of the PPDU according to an embodiment of the present invention is 20 MHz or 40 MHz. The same description as that of FIG. 16 will be omitted.

[0178] According to an embodiment of the present invention, the locator subfield may not be present based on the bandwidth (or channel width). The bandwidth may be the PPDU bandwidth. Also, the bandwidth may be the bandwidth value included in the U-SIG field. For example, if the bandwidth is 20 MHz or 40 MHz, the locator subfield may not be present.

[0179] In one embodiment, when the bandwidth is 20 MHz, there may be one RU allocation subfield. The RU allocation subfield may correspond to the 20 MHz band. Therefore, referring to FIG. 16, the EHT-SIG field or the common field may include one RU allocation subfield, a CRC, and a tail. The CRC may be for one RU allocation subfield.

[0180] In one embodiment, when the bandwidth is 40 MHz, there may be two RU allocation subfields across all content channels. Thus, each of the two content channels may include one RU allocation subfield and may include a corresponding CRC and tail. In yet another embodiment, when the bandwidth is 40 MHz, each content channel may include two RU allocation subfields and may include a CRC and tail corresponding to the two RU allocation subfields. In this case, compared to including one RU allocation subfield in each content channel, there is an advantage that RU allocation signaling can be freely performed. In addition, when including one RU allocation subfield in each content channel, there is an advantage that signaling overhead is reduced.

[0181] According to an embodiment of the present invention, the locator subfield may be present when the bandwidth is 80 MHz or greater.

[0182] FIG. 17 is a diagram showing an EHT-SIG structure of an 80 MHz PPDU according to one embodiment of the present invention.

[0183] In the embodiment of FIG. 17, the same content as described above may be omitted, and the number of 1 RU allocation subfields may be represented as N_RA.

[0184] According to one embodiment of the present invention, a locator subfield may be included when the bandwidth is 80 MHz. The locator subfield when the bandwidth is 80 MHz may be the same locator subfield as described above.

[0185] For example, the locator subfield may be 4 bits, and each bit may correspond to a 20 MHz band. When each bit of the locator subfield indicates a 20 MHz band in signaling based on the locator subfield, each content channel may have up to 4 RU assignment subfields. However, by using multiple content channels, it is possible to limit the RU assignment subfields that each content channel may include in order to reduce the signaling overhead of the EHT-SIG field. When the bandwidth is 80 MHz, all types of RU assignments can be signaled by using only a maximum of 4 RU assignment subfields in the entire content channel. Therefore, according to an embodiment of the present invention, each content channel may have one or two RU assignment subfields. Also, the number of content channels may be two. FIG. 17(a) shows an example in which two content channels each include a locator subfield (4 bits), one or two RU assignment subfields, a CRC, and a tail. In this case, as described in FIG. 11, a problem may occur in which the length of the RU allocation subfield is not known before checking the locator subfield, and the problem can be solved by utilizing the embodiments described in FIG. 14 and FIG. 15.

[0186] However, in the embodiment of Figure 17(a), there are only two cases of RU allocation in each content channel, 1 or 2, but it is indicated by a 4-bit locator subfield. Therefore, in order to reduce signaling overhead, the number of RU allocation subfields may be indicated by 1-bit signaling. For example, the 1-bit signaling may be included in a common field.

[0187] Referring to FIG. 17(b), the More RU allocation subfield may be the 1-bit signaling. Therefore, each content channel may include the More RU allocation subfield, one or two RU allocation subfields, a CRC, and a tail. In this case, the problem of not knowing the RU allocation subfield length before checking the locator subfield may occur similarly as described in FIG. 11. The problem of not knowing the RU allocation subfield length before checking the More RU allocation subfield in FIG. 17(b) may occur.

[0188] Therefore, in order to solve this, the embodiment described in FIG. 14 and FIG. 15 can be used. In the embodiment of FIG. 14 and FIG. 15, an embodiment can be performed using a More RU allocation subfield instead of a locator subfield. That is, a CRC corresponding to the More RU allocation subfield may exist separately from a CRC for the RU allocation subfield. Alternatively, the More RU allocation subfield and a previously set number (1) of RU allocation subfields may be used for CRC calculation, and if there is an additional RU allocation subfield, a CRC and a tail may exist. Therefore, it is possible to decode the More RU allocation subfield without knowing the number of RU allocation subfields. In yet another embodiment, the More RU allocation subfield may be included in the U-SIG field. For example, the More RU allocation subfield included in the U-SIG field may be a subfield used for another purpose if it is not an 80 MHz PPDU. For example, the puncturing information or the bandwidth field can be used as the More RU allocation subfield.

[0189] According to the embodiment of FIG. 17(c), the locator subfield or the More RU allocation subfield may not be present. When the bandwidth is 80 MHz, the number of bits of the locator subfield or the More RU allocation subfield is less than when a larger bandwidth is used, so it is possible to omit such bits and include multiple RU allocation subfields. For example, two RU allocation subfields may be included for each content channel. Therefore, when there are two content channels as shown in FIG. 17(c), a total of four RU allocation subfields can be included to express all RU allocation. This makes it easier to implement than decoding the locator subfield or the More RU allocation subfield. As another embodiment, four RU allocation subfields may be included for each content channel. In this case, the four RU allocation subfields may correspond to each 20 MHz band. That is, it is possible to signal all of the 80 MHz band in each content channel, and there is an advantage that signaling flexibility can be obtained.

[0190] In the embodiment of FIG. 17(a), the role of the locator subfield is reduced in the embodiments of FIG. 17(b) and (c), so it is necessary to determine the position of the channel (band) corresponding to the RU allocation subfield in FIG. 17(b) and (c). For example, the RU allocation subfields may correspond to already set channels. For example, the RU allocation subfield of content channel 1 may correspond to the first 20 MHz channel and the third 20 MHz channel from the lowest frequency. Also, the RU allocation subfield of content channel 2 may correspond to the second 20 MHz channel and the fourth 20 MHz channel from the lowest frequency. The channel corresponding to the RU allocation subfield of each content channel is not limited to this, and may be another already set channel.

[0191] 18 shows an example of center 26-tone RU signaling according to an embodiment of the present invention. In the embodiment of FIG. 18, the contents described in FIG. 17 and the like may be omitted.

[0192] According to an embodiment of the present invention, the bandwidth of the PPDU may include a center 26-tone RU. For example, the center 26-tone RU may be a 26-tone RU located in the center of the 80 MHz PPDU. In addition, the center 26-tone RU may be an RU with a subcarrier index of [-16:-4, 4:16] when the subcarrier index of the DC tone is 0. This may be the index in the case of an 80 MHz PPDU. If the PPDU is a 160 (80 + 80) MHz PPDU, a center 26-tone RU may be located in the center of each 80 MHz. That is, there may be two center 26-tone RUs. If the PPDU is a 160 (80 + 80) MHz PPDU, the subcarrier indexes of the two center 26-tone RUs may be [-528:-516, -508:-496] or [496:508, 516:528]. Also, in the case of 240 or 320 MHz PPDU, there may be three or four center 26-tone RUs, respectively.

[0193] According to one embodiment of the present invention, when the bandwidth is 20 MHz or 40 MHz, center 26-tone RU signaling may be present.

[0194] According to an embodiment of the present invention, when the bandwidth is 80 MHz, center 26-tone RU signaling may be present. Referring to FIG. 18, center 26-tone RU signaling may be performed by a center 26-tone RU subfield. According to an embodiment, a center 26-tone RU subfield value of 1 may mean that a user is assigned to the center 26-tone RU or that a corresponding user field exists. Also, a center 26-tone RU subfield value of 0 may mean that a user is not assigned to the center 26-tone RU or that a corresponding user field does not exist. If the center 26-tone RU subfield value is 1, a corresponding user field may exist behind the same content channel. In this case, the CRC can be calculated including the center 26-tone RU subfield.

[0195] Referring to FIG. 18(a), the center 26-tone RU subfield may be present in all content channels. In this case, there is an advantage that the center 26-tone RU can be signaled in any content channel, and there is signaling flexibility. In this case, a user field for the center 26-tone RU may be present only in a content channel in which the center 26-tone RU subfield is set to 1. As yet another embodiment, the center 26-tone RU subfield may be present in all content channels, and the values ​​may be the same. Therefore, no matter what content channel a receiver is watching, it is possible to confirm signaling for the center 26-tone RU.

[0196] Referring to FIG. 18(b), only one center 26-tone RU subfield may exist in the already-established content channel. In this case, there is an advantage that the signaling overhead can be reduced compared to the embodiment of FIG. 18(a). The already-established content channel may be content channel 1. Also, content channel 1 may be a content channel corresponding to the lowest frequency 20 MHz channel. Or, content channel 1 may be a content channel corresponding to the P20 channel. Also, when a channel signaled by the already-established content channel is punctured, the center 26-tone RU subfield may exist in another content channel. For example, it is possible to determine the position where the center 26-tone RU subfield exists based on the puncturing information included in the U-SIG field. Also, the user field corresponding to the center 26-tone RU may be signaled in the content channel in which the center 26-tone RU subfield exists.

[0197] Figure 19 shows another example of center 26-tone RU signaling according to an embodiment of the present invention. In the embodiment of Figure 19, the same content as described above may be omitted, and the described embodiments may be combined and used.

[0198] According to an embodiment of the present invention, the EHT-SIG signaling in the primary channel and the non-primary channel may be different. Or, the center 26-tone RU signaling in the primary channel and the non-primary channel may be different. Therefore, the number (or length) of center 26-tone RU subfields in the primary channel may be different from the number (or length) of center 26-tone RU subfields in the non-primary channel. The primary channel can mean a primary 80 MHz channel or a primary 160 MHz channel.

[0199] According to one embodiment of the present invention, the EHT-SIG of the primary channel can include signaling for all center 26-tone RUs. For example, the EHT-SIG of the primary 80 MHz channel can include signaling for all center 26-tone RUs. That is, when the bandwidth is 160 (80+80), 320 (160+160), or 240 (80+160 or 160+80) MHz, the primary channel can include signaling for two center 26-tone RUs, four center 26-tone RUs, and three center 26-tone RUs, respectively. As yet another embodiment, the primary channel can be a primary 160 MHz channel. By including signaling for all center 26-tone RUs in the primary channel, signaling flexibility in the primary channel can also be obtained. Also, the signaling for all center 26-tone RUs can be distributed to the content channel. For example, signaling for two center 26-tone RUs present at 160 (80 + 80) MHz can be included in two content channels, one each. Also, signaling for four center 26-tone RUs present at 320 (160 + 160) MHz can be included in two content channels, two each. Also, signaling for three center 26-tone RUs present at 240 (80 + 160 or 160 + 80) MHz can be included in two content channels, one each (or one each). Therefore, in the case of 160 (80 + 80) MHz, each content channel can include one bit of the center 26-tone RU subfield. Also, in the case of 320 (160 + 160) MHz, each content channel can include two bits of the center 26-tone RU subfield. Also, in the case of 240 (80+160 or 160+80) MHz, the two content channels can include center 26-tone RU subfields of 2 bits and 1 bit (or 1 bit and 2 bits), respectively.

[0200] Referring to FIG. 19, in the portion labeled P80, each content channel includes a center 26-tone RU subfield with 1 or 2 bits.

[0201] As yet another example, in order to have signaling flexibility, each content channel can include signaling for all center 26-tone RUs. Thus, each content channel can include signaling for 2-bit center 26-tone RU subfield, 4-bit center 26-tone RU subfield, and 3-bit center 26-tone RU subfield when the bandwidth is 160 (80+80), 320 (160+160), and 240 (80+160 or 160+80) MHz, respectively.

[0202] Also, there may be cases where static puncturing is performed. Static puncturing may mean a case where a specific channel is punctured no matter which PPDU is transmitted. Also, static puncturing may not be dynamic puncturing that is determined every time a PPDU is transmitted. Also, static puncturing may be determined during an association process. If static puncturing is performed, the center 26-tone RU subfield for the center 26-tone RU included in or spanning the punctured channel of the static puncturing may be set to 0. That is, a user may not be assigned to the center 26-tone RU. Alternatively, if static puncturing is performed, the center 26-tone RU subfield for the center 26-tone RU included in or spanning the punctured channel of the static puncturing may not exist. Therefore, the presence or absence of center 26-tone RU subfields or the number of center 26-tone RU subfields can be determined based on fixed puncturing.

[0203] According to an embodiment of the present invention, there may be an STA that transmits or receives a PPDU on a channel other than the primary channel. This can be called a STA parked on a non-primary channel. By parking an STA on a non-primary channel, it is possible to alleviate a situation in which the primary channel is busy.

[0204] According to an embodiment of the present invention, any RU can be assigned to a STA parked on a non-primary channel. In this case, the non-primary channel EHT-SIG can include signaling for all center 26-tone RUs. Therefore, the primary channel EHT-SIG and the non-primary channel EHT-SIG can have the same structure, and the above-mentioned primary channel center 26-tone RU signaling can be applied to channels other than the primary channel.

[0205] According to yet another embodiment of the present invention, the channels that can be assigned to STAs parked on non-primary channels may be limited to 80 MHz. For example, the channels that can be assigned to the EHT-SIG field of a certain channel may be limited to 80 MHz including the certain channel. Referring to FIG. 19, the range in which the EHT-SIG of each 80 MHz subband can be signaled may be limited to the 80 MHz subband. In this case, one center 26-tone RU may exist in an 80 MHz subband that is not a primary 80 MHz channel. Therefore, the same center 26-tone RU signaling method as described in FIG. 18 can be applied to channels that are not primary 80 MHz channels. Referring to FIG. 19, the same center 26-tone RU signaling method as described in FIG. 18(a) can be applied to channels that are not primary 80 MHz channels. Therefore, in FIG. 19, there is one center 26-tone RU signaled in 80 MHz sub-band 2 when the PPDU bandwidth is 160, 320, or 240 MHz, and FIG. 19 shows an example in which the center 26-tone RU is signaled in all content channels.

[0206] According to yet another embodiment of the present invention, a channel that can be assigned to a STA parked in a non-primary channel may be limited to 160 MHz. For example, a channel that can be assigned to an EHT-SIG field of a certain channel may be limited to 160 MHz including the certain channel. Referring to FIG. 19, a range in which the EHT-SIG of each 80 MHz subband can be signaled may be limited to a P160 channel or an S160 channel including the 80 MHz subband. In this case, the number of center 26-tone RUs that an 80 MHz subband that is not a primary 80 MHz channel signals may be two. Therefore, when all the two center 26-tone RUs can be signaled in all the content channels, a 2-bit center 26-tone RU subfield may be included in each content channel. Or, when two center 26-tone RU signalings are assigned separately to the content channel, a 1-bit center 26-tone RU subfield may be included in each content channel. The EHT-SIG corresponding to the 80 MHz subband 2 in FIG. 19 may represent such a case.

[0207] If the bandwidth is 240 MHz and the two 80 MHz channels excluding the primary 80 MHz channel are designated as non-P80 channel 1 and non-P80 channel 2, then in non-P80 channel 1, two center 26-tone RUs can be signaled as described above, and in non-P80 channel 2, the same center 26-tone RU can be signaled as in the case where the allocatable channels are limited to 80 MHz described above.

[0208] Figure 20 shows another example of center 26-tone RU signaling according to an embodiment of the present invention. In the embodiment of Figure 20, the same content as described above may be omitted, and the described embodiments may be combined and used.

[0209] According to an embodiment of the present invention, all center 26-tone RUs can be signaled in the EHT-SIG signaled on any channel. Therefore, the length (or number) of the center 26-tone RU subfields can be determined based on the bandwidth. If the bandwidth is smaller than 80 MHz, the center 26-tone RU subfields may not exist.

[0210] Also, when the bandwidth is 80, 160 (80+80), 240 (80+160 or 160+80), 320 (160+160) MHz, the center 26-tone RU subfield may be 1, 2, 3, or 4 bits, respectively. According to one embodiment, when the center 26-tone RU subfield has a number of bits, each bit may be mapped from a lower frequency center 26-tone RU to a higher frequency center 26-tone RU, respectively.

[0211] The center 26-tone RU subfield described in Figures 18 to 20 may be used in CRC calculation together with the RU allocation subfield. Alternatively, the center 26-tone RU subfield described in Figures 18 to 20 may be used in CRC calculation together with the locator subfield and the RU allocation subfield. Alternatively, the center 26-tone RU subfield may not exist as an independent subfield, and some bits of the locator subfield may play the role of the center 26-tone RU subfield. In other words, some bits of the locator subfield can perform center 26-tone RU signaling.

[0212] FIG. 21 illustrates yet another example of an EHT-SIG structure according to an embodiment of the present invention.

[0213] According to an embodiment of the present invention, the EHT-SIG field may include a dummy RU assignment subfield. The dummy RU assignment subfield may be the dummy RU assignment subfield mentioned in the previous embodiment or dummy data. Also, the dummy RU assignment subfield may mean one entry among values ​​that the RU assignment subfield may have. That is, the RU assignment subfield set to a specific value may be called a dummy RU assignment subfield.

[0214] In addition, the length (number of bits) of the dummy RU allocation subfield may be the same as the length (number of bits) of the RU allocation subfield. Also, it is possible for multiple dummy RU allocation subfields to exist in one content channel.

[0215] According to one embodiment of the present invention, a locator subfield can indicate the presence of a dummy RU assignment subfield. For example, the locator subfield can indicate the dummy RU assignment subfield in the same way that the locator subfield indicates the RU assignment subfield. That is, a bit of the locator subfield that is 1 can indicate the RU assignment subfield or the dummy RU assignment subfield. Also, a bit of the locator subfield that is 1 can be mapped to the following RU assignment subfield or the dummy RU assignment subfield in order. Therefore, the number of bits of the locator subfield that is 1 can be the same as the sum of the number of RU assignment subfields and the number of dummy RU assignment subfields. Also, the dummy RU assignment subfield can be present at any position compared to the RU assignment subfield.

[0216] Figure 21 may show a structure of a common field of the EHT-SIG field. Referring to Figure 21, a locator subfield, an RU allocation subfield, a dummy RU allocation subfield, a center 26-tone RU subfield, a CRC, and a tail may be included in the EHT-SIG field. In this case, a plurality of RU allocation subfields may be included as described in Figures 14 to 16.

[0217] Here, multiple RU assignment subfields are illustrated as one RU assignment subfield. Also, the dummy RU assignment subfield is illustrated as a hatched area. Referring to Figure 21, the dummy RU assignment subfield may be present in content channel 1. Also, a position indicator subfield can indicate the presence and position of the dummy RU assignment subfield. Figure 21 shows an embodiment in which the dummy RU assignment subfield is located before the RU assignment subfield.

[0218] According to one embodiment, the dummy RU assignment subfield may not indicate RU configuration or assignment. In addition, the dummy RU assignment subfield may not be related to the number of tones and / or bandwidth, and may mean that there is no corresponding user or that there is no RU to assign. Therefore, there may be no user field corresponding to the dummy RU assignment subfield.

[0219] Therefore, when the receiver interprets the EHT-SIG, the bits of the dummy RU allocation subfield and the locator subfield corresponding to the dummy RU allocation subfield can be ignored. For example, when the locator subfield is set to 11001000 (B0B1..B7), a total of three RU allocation subfields and dummy RU allocation subfields may follow. If the RU allocation subfield 1, the dummy RU allocation subfield, and the RU allocation subfield 2 follow in this order, the RU allocation subfield 1 may correspond to B0, the dummy RU allocation subfield may correspond to B1, and the RU allocation subfield 2 may correspond to B4. Therefore, the RU allocation subfield 2 may be RU allocation information for the frequency position corresponding to B4. In addition, the user field may be followed by the user field corresponding to the RU allocation subfield 2 after the user field corresponding to the RU allocation subfield 1. There may be no user field corresponding to the dummy RU allocation subfield.

[0220] In yet another embodiment, when a locator subfield exists in a plurality of content channels, the presence and number of dummy RU allocation subfields can be determined based on the number of RU allocation subfields indicated by the locator subfield of each content channel. For example, when there is a number N1 of RU allocation subfields indicated by a locator subfield existing in content channel 1, a number N2 of RU allocation subfields indicated by a locator subfield existing in content channel 2, ..., and a number Nn of RU allocation subfields indicated by a locator subfield existing in content channel n, the presence and number of dummy RU allocation subfields can be determined based on N1, N2, ..., Nn. More specifically, the presence and number of dummy RU allocation subfields can be determined based on the maximum value of N1, N2, ..., Nn. For example, the number of RU allocation subfields in content channel m can be ((maximum value of N1, N2, ..., Nn)-Nm). Therefore, the values ​​of the number of RU allocation subfields and the number of dummy RU allocation subfields of each content channel can be constant. At this time, the position of the dummy RU allocation subfield may already be set. For example, the position of the dummy RU allocation subfield may be after the RU allocation subfield and before the center 26-tone RU subfield.

[0221] By using the dummy RU allocation subfield, it is possible to adjust the length of the field for each channel. For example, the first and last of the RU allocation subfield and the dummy RU allocation subfield can be adjusted to be the same for each channel. Referring to FIG. 21, the length of the RU allocation subfield for the content channel 2 is longer than the length of the RU allocation subfield for the content channel 1, but by including the dummy RU allocation subfield in the content channel 1, the sum of the lengths of the RU allocation subfield and the dummy RU allocation subfield for the content channel 1 may be the same as the length of the RU allocation subfield for the content channel 2. This has the advantage of making it easier to implement when generating and decoding the EHT-SIG.

[0222] FIG. 22 is a flowchart illustrating an example of a method for receiving and decoding a PPDU according to an embodiment of the present invention.

[0223] Referring to Fig. 22, a non-AP (Access Point) STA (Station) can receive a PPDU preamble from an AP (S22010). The PPDU preamble may have the same structure as described in Figs. 14 to 16. For example, the PPDU may be an EHT PPDU, and the EHT PPDU may be an SU PPDU or an MU PPDU.

[0224] The preamble of the PPDU may include an EHT-SIG field that includes one or more EHT SIG content channels, as described in FIG. 15, and each of the one or more EHT SIG content channels may include a common field and a user-specific field.

[0225] The common field may include a specific field (e.g., a locator subfield), at least one first resource unit (RU) allocation subfield, a first CRC, and a first tail, and may further include at least one second resource unit allocation subfield, a second CRC, and a second tail according to specific conditions.

[0226] In this case, a specific field (e.g., a locator subfield), at least one first resource unit (RU) allocation subfield, a first CRC, and a first tail can constitute a first encoding block, and at least one second resource unit allocation subfield, a second CRC, and a second tail can constitute a second encoding block.

[0227] In this case, the first encoding block may further include a spatial reuse subfield indicating whether spatial reuse is used, a GI+LTF size subfield indicating the GI duration and the size of the EHT-LTF, an EHT LTF symbol number field indicating the number of EHT-LTF symbols, an LDPC extra symbol sequence subfield indicating the presence or absence of an LDPC extra symbol sequence, a pre-FEC padding element subfield indicating a pre-FEC padding element, and a PE ambiguity subfield indicating PE disambiguity, as described above.

[0228] In this case, the second encoding block may not be included due to the bandwidth of the PPDU indicated by the bandwidth field of the U-SIG field, as described above.

[0229] After that, the STA can identify the packet configuration of the received preamble (S22020), that is, the STA can identify the format of the preamble of the received PPDU.

[0230] For example, the STA can determine whether the common field further includes at least one second RU allocation subfield, i.e., whether the common field includes a second encoding block in addition to the first encoding block.

[0231] Specifically, the STA can determine whether at least one second RU allocation subfield is included based on a specific field located before at least one first RU allocation subfield. For example, the size and value of the locator subfield may be determined based on the bandwidth of the PPDU indicated by the bandwidth field of the U-SIG field, and the number of first RU allocation subfields and second RU allocation subfields may be identified based on the locator subfield. Based on this, the STA can determine whether a second RU allocation subfield is included and further whether a second encoding block is included in the common field.

[0232] That is, it can be determined (or identified) whether at least one second RU allocation subfield is included in the common field depending on the bandwidth indicated based on the bandwidth field of the U-SIG.

[0233] Also, as described above, some of the common fields may be set to the same value for one or more EHT-SIG content channels, and the remaining fields may be set to different values ​​individually.

[0234] For example, some or all of the bits of a particular field (e.g., a locator subfield) may be set to the same value between content channels. In this case, fields that can be set to the same value include some bits of the locator subfield, the spatial reuse subfield, the GI+LTF size subfield, the number of EHT LTF symbols field, the LDPC extra symbol sequence subfield, the Pre-FEC padding element subfield, and the PE ambiguity subfield.

[0235] Also, as described above, each encoding block may be encoded / decoded separately, i.e., at least one first RU allocated subfield and at least one second RU allocated subfield may be encoded / decoded separately.

[0236] As described above, the STA that has identified the packet configuration can perform decoding based on the identified packet configuration (e.g., whether or not a second encoding block and / or at least one second RU allocation subfield is included) (S22030).

[0237] The STA may then receive the data of the PPDU based on the decoded preamble, i.e., receive the data of the PPDU in the RU assigned by the preamble.

[0238] FIG. 23 is a flowchart illustrating an example of a method for generating and transmitting a PPDU according to an embodiment of the present invention.

[0239] Specifically, the AP may generate a PPDU to be transmitted to at least one STA (S23010). At this time, the PPDU may be composed of a preamble and data.

[0240] The preamble of the PPDU may have the same structure as that described in Figures 14 to 16. For example, the PPDU may be an EHT PPDU, and the EHT PPDU may be a SU PPDU or an MU PPDU.

[0241] The preamble of the PPDU may include an EHT-SIG field that includes one or more EHT SIG content channels, as described in FIG. 15, and each of the one or more EHT SIG content channels may include a common field and a user-specific field.

[0242] The common field may include a specific field (e.g., a locator subfield), at least one first resource unit (RU) allocation subfield, a first CRC, and a first tail, and may further include at least one second resource unit allocation subfield, a second CRC, and a second tail according to specific conditions.

[0243] In this case, a specific field (e.g., a locator subfield), at least one first resource unit (RU) allocation subfield, a first CRC, and a first tail can constitute a first encoding block, and at least one second resource unit allocation subfield, a second CRC, and a second tail can constitute a second encoding block.

[0244] In this case, as described above, the first encoding block may further include a spatial reuse subfield indicating whether spatial reuse is used, a GI+LTF size subfield indicating the GI duration and the size of the EHT-LTF, an EHT LTF symbol number field indicating the number of EHT-LTF symbols, an LDPC extra symbol sequence subfield indicating the presence or absence of an LDPC extra symbol sequence, a Pre-FEC padding element subfield indicating a pre-FEC padding element, and a PE ambiguity subfield indicating PE disambiguity.

[0245] In this case, the second encoding block may not be included due to the bandwidth of the PPDU indicated by the bandwidth field of the U-SIG field, as described above.

[0246] Specifically, whether at least one second RU allocation subfield is included may be identified based on a specific field located before at least one first RU allocation subfield. For example, the size and value of the locator subfield may be determined based on the bandwidth of the PPDU indicated by the bandwidth field of the U-SIG field, and the number of first RU allocation subfields and second RU allocation subfields may be identified based on the locator subfield. Therefore, whether a second RU allocation subfield is included and further whether a second encoding block is included in the common field may be identified based on the bandwidth of the PPDU.

[0247] That is, whether at least one second RU allocation subfield is included in the common field may be determined (or identified) depending on the bandwidth indicated based on the bandwidth field of the U-SIG.

[0248] Also, as described above, some of the common fields may be set to the same value for one or more EHT-SIG content channels, and the remaining fields may be set to different values ​​individually.

[0249] For example, some or all of the bits of a particular field (e.g., a locator subfield) may be set to the same value between content channels. In this case, fields that can be set to the same value include some bits of the locator subfield, the spatial reuse subfield, the GI+LTF size subfield, the number of EHT LTF symbols field, the LDPC extra symbol sequence subfield, the Pre-FEC padding element subfield, and the PE ambiguity subfield.

[0250] Also, as described above, each encoding block may be encoded / decoded separately, i.e., at least one first RU allocated subfield and at least one second RU allocated subfield may be encoded / decoded separately.

[0251] The AP can then transmit the generated PPDU to at least one STA via each RU (S23020).

[0252] 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 idea or essential features of the present invention. Therefore, the above-described embodiments should be understood as illustrative and not restrictive in all respects. 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.

[0253] The scope of the present invention is indicated by the claims set forth below rather than by the above detailed description, and all modifications and variations derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention. [Explanation of symbols]

[0254] 100 Stations 110 Processor 120 Communications Department 140 User Interface Section 150 display units 160 Memory

Claims

1. A terminal of a wireless communication system, Communication module and a processor configured to control the communication module; The processor, receiving a physical layer protocol data unit (PPDU) from an access point (AP) including one or more signal (SIG) content channels; each of the one or more SIG content channels includes a user specific field including at least one first resource unit (RU) allocation subfield and a common field; Identifying whether the common field further includes at least one second RU allocation subfield; and decoding the common field included in the PPDU; The PPDU includes a specific subfield associated with a bandwidth over which the PPDU is transmitted; A terminal, wherein the specific subfield is used to identify (i) the number of the at least one first RU assigned subfield, (ii) whether at least one second RU assigned subfield is included in the common field, and (iii) the number of the at least one second RU assigned subfield if the at least one second RU assigned subfield is included in the common field.

2. the common field includes a first coding block and a second coding block in which the at least one first RU assigned subfield and the at least one second RU assigned subfield are encoded separately; the one or more SIG content channels are transmitted at fixed bandwidth intervals according to the bandwidth; The terminal of claim 1 , wherein the specific subfield is set to the same value for each of the one or more SIG content channels.

3. The terminal of claim 2 , wherein each of the first coding block and the second coding block is decoded separately.

4. the at least one first RU assigned subfield is encoded into the first coding block together with a first cyclic redundancy code (CRC) and a first tail; The terminal of claim 2 , wherein the at least one second RU allocation subfield is encoded in the second coding block together with a second CRC and a second tail.

5. The terminal of claim 1 , wherein the specific subfield is located before the at least one first RU assigned subfield.

6. A method for a terminal receiving data in a wireless communication system, comprising: receiving, from an access point (AP), a physical layer protocol data unit (PPDU) including one or more signal (SIG) content channels, each of the one or more SIG content channels including a user specific field including at least one first resource unit (RU) allocation subfield and a common field; identifying whether the common field further includes at least one second RU allocation subfield; and decoding the common field included in the PPDU; The EHT PPDU includes a specific subfield associated with a bandwidth over which the ETH PPDU is transmitted; The method, wherein the specific subfield is used to identify (i) the number of the at least one first RU assigned subfield, (ii) whether at least one second RU assigned subfield is included in the common field, and (iii) the number of the at least one second RU assigned subfield if the at least one second RU assigned subfield is included in the common field.

7. the common field includes a first coding block and a second coding block in which the at least one first RU assigned subfield and the at least one second RU assigned subfield are encoded separately; the one or more SIG content channels are transmitted at fixed bandwidth intervals according to the bandwidth; The method of claim 6 , wherein the specific subfield is set to the same value for each of the one or more SIG content channels.

8. The method of claim 7 , wherein each of the first coding block and the second coding block is decoded separately.

9. the at least one first RU assigned subfield is encoded into the first coding block together with a first cyclic redundancy code (CRC) and a first tail; The method of claim 7 , wherein the at least one second RU allocated subfield is encoded in the second coding block along with a second CRC and a second tail.

10. The method of claim 6 , wherein the specific subfield is located before the at least one first RU-allocated subfield.

11. An access point (AP) of a wireless communication system, comprising: Communication module and a processor configured to control the communication module; The processor, generating a physical layer protocol data unit (PPDU) including one or more signal (SIG) content channels, each of the one or more SIG content channels includes a user specific field including at least one first resource unit (RU) allocation subfield and a common field; transmitting the EHT PPDU; The EHT PPDU includes a specific subfield associated with a bandwidth over which the EHT PPDU is transmitted; An access point, wherein the specific subfield is used to identify (i) the number of the first RU allocation subfields, (ii) whether at least one second RU allocation subfield is included in the common field, and (iii) the number of the at least one second RU allocation subfield according to the bandwidth size indicated by the specific subfield if the at least one second RU allocation subfield is included in the common field.

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