KR20180026768A - A wireless communication method using a signaling field and a wireless communication terminal - Google Patents

Abstract

A wireless communication terminal for wirelessly communicating is disclosed. The wireless communication terminal includes a transmission / reception unit; And a processor. The processor transmits a legacy signaling field including information decodable by the legacy wireless communication terminal through the transceiver and a legacy training signal for setting reception of a legacy signaling field. When transmitting the legacy signaling field, the processor transmits a predetermined signal through at least one of a plurality of subcarriers corresponding to a guard carrier position of the legacy training signal.

Description

A wireless communication method using a signaling field and a wireless communication terminal

The present invention relates to a wireless communication method and a wireless communication terminal using a signaling field.

Recently, as the spread of mobile devices has expanded, wireless LAN technology capable of providing fast wireless Internet service has attracted much attention. Wireless LAN technology is a technology that enables wireless devices such as smart phones, smart pads, laptop computers, portable multimedia players, and embedded devices to wirelessly connect to the Internet at home, to be.

IEEE (Institute of Electrical and Electronics Engineers) Since 802.11 supports the initial wireless LAN technology using 2.4 GHz frequency, various technology standards are being put into practical use or under development. First, IEEE 802.11b supports a communication speed of up to 11 Mbps while using a frequency of 2.4 GHz band. IEEE 802.11a, which has been commercialized since IEEE 802.11b, uses the frequency of the 5 GHz band instead of the 2.4 GHz band, thereby reducing the influence on interference compared to the frequency of the highly congested 2.4 GHz band. Orthogonal Frequency Division Multiplexing OFDM) technology to improve communication speed up to 54Mbps. However, IEEE 802.11a has a short communication distance compared to IEEE 802.11b. IEEE 802.11g, like IEEE 802.11b, uses a frequency of 2.4GHz band to achieve a communication speed of up to 54Mbps and has received considerable attention because it meets backward compatibility. It is in the lead.

IEEE 802.11n is a technical standard established to overcome the limitation of the communication speed which is pointed out as a weak point in the wireless LAN. IEEE 802.11n aims to increase the speed and reliability of the network and to extend the operating distance of the wireless network. More specifically, IEEE 802.11n supports high throughput (HT) with data rates of up to 540 Mbps or higher, and uses multiple antennas at both ends of the transmitter and receiver to minimize transmission errors and optimize data rates. It is based on Multiple Inputs and Multiple Outputs (MIMO) technology. In addition, the specification may use a coding scheme that transfers multiple duplicate copies to increase data reliability.

As the spread of the wireless LAN is activated and the applications using it are diversified, there is a need for a new wireless LAN system to support a very high throughput (VHT) higher than the data processing speed supported by IEEE 802.11n . IEEE 802.11ac supports wide bandwidth (80MHz ~ 160MHz) at 5GHz frequency. The IEEE 802.11ac standard is defined only in the 5GHz band, but for backward compatibility with existing 2.4GHz band products, early 11ac chipsets will also support operation in the 2.4GHz band. Theoretically, according to this standard, the wireless LAN speed of multiple stations is at least 1Gbps and the maximum single link speed is at least 500Mbps. This is accomplished by extending the concept of wireless interfaces that are accepted by 802.11n, including wider radio frequency bandwidth (up to 160 MHz), more MIMO spatial streams (up to 8), multiuser MIMO, and high density modulation (up to 256 QAM). In addition, IEEE 802.11ad is a method of transmitting data using a 60 GHz band instead of the existing 2.4 GHz / 5 GHz. IEEE 802.11ad is a transmission specification that uses beamforming technology to provide speeds of up to 7 Gbps, making it suitable for high bitrate video streaming, such as large amounts of data or uncompressed HD video. However, the 60GHz frequency band has a disadvantage in that it is difficult to pass through obstacles, and therefore, it can be used only between devices in a near space.

Recently, as a next generation wireless LAN standard after 802.11ac and 802.11ad, discussions for providing high-efficiency and high-performance wireless LAN communication technology in a high density environment have been continuing. That is, in the next generation wireless LAN environment, communication with high frequency efficiency should be provided in the presence of a high density station and an access point (AP), and various techniques are required to realize this.

Particularly, as the number of devices using a wireless LAN increases, it is necessary to use a predetermined channel efficiently. Therefore, there is a need for a technique that enables efficient use of bandwidth by simultaneously transmitting data between a plurality of stations and an AP.

An embodiment of the present invention aims to provide an efficient wireless communication method and a wireless communication terminal using a signaling field.

In particular, it is an object of the present invention to provide a wireless communication method and a wireless communication terminal supporting a plurality of signaling field formats.

According to an embodiment of the present invention, a wireless communication terminal that wirelessly communicates includes a transmitting and receiving unit; And a processor for transmitting a legacy training signal for reception setting of a legacy signaling field and a legacy signaling field including information decodable by a legacy wireless communication terminal through the transceiver, And transmits a predetermined first signal through at least one subcarrier among a plurality of subcarriers corresponding to a guard carrier position of the legacy training signal.

Wherein the processor is configured to transmit, when transmitting the legacy signaling field, at least one of a plurality of subcarriers that transmit data of the legacy signaling field and a pilot signal among a plurality of subcarriers corresponding to positions of guard carriers of the legacy training signal, Lt; RTI ID = 0.0 > 1 < / RTI >

When transmitting the legacy signaling field, the processor is configured to transmit, at a frequency of 0, a position of two subcarriers having a highest frequency among a plurality of subcarriers corresponding to a position of a left guard carrier of the legacy training signal and a right guard carrier The first signal can be transmitted through two subcarriers having the lowest frequency among the plurality of subcarriers.

Wherein the processor transmits the repeated legacy signaling field generated based on the legacy signaling field after transmitting the legacy signaling field and transmits the repeated legacy signaling field generated based on the legacy signaling field to a position corresponding to a position of the guard carrier of the legacy training signal A predetermined second signal can be transmitted through at least any one of a plurality of subcarriers.

The processor may repeat the legacy signaling field to generate the repeating legacy signaling field.

The processor may signal information other than the legacy signaling field through a combination of the first signal and the second signal.

The first signal and the second signal may be the same.

Wherein the legacy signaling field includes length information indicating a duration of a non-legacy physical layer frame after a legacy signaling field, and the processor transmits the length information to a data size < RTI ID = 0.0 > Information other than the information indicating the duration of the non-legacy physical layer frame can be signaled through the remainder value obtained by dividing the non-legacy physical layer frame.

Wherein the processor indicates that information other than the information indicating the duration of the non-legacy physical layer frame indicates whether the non-legacy physical layer frame includes a first signaling field, and the first signaling field indicates that the wireless communication terminal has a plurality of When data is transmitted to a wireless communication terminal, information related to a plurality of wireless communication terminals can be signaled.

Wherein the information indicating the duration of the non-legacy physical layer frame indicates whether the second signaling field included in the non-legacy physical layer frame includes a field repeated in the time domain, and the second signaling field indicates either And can be commonly used when data is transmitted to a plurality of wireless communication terminals.

Wherein the processor divides the length information into a residual value obtained by dividing the length information by a data size that can be transmitted by one OFDM symbol transmitting a legacy physical layer frame and a modulation method of a second OFDM symbol transmitting the second signaling field, Information other than the information indicating the duration of the legacy physical layer frame can be signaled.

The modulation method may be binary phase shift keying (BPSK) or quadrature binary phase shift keying (QBPSK).

A wireless communication terminal for wirelessly communicating according to an embodiment of the present invention includes a transmitting and receiving unit; And a processor for receiving a legacy training signal for reception setup of a legacy signaling field via the transceiver and generating a legacy signaling field including information that the legacy wireless communication terminal can decode based on the legacy training signal, Receiving a first signal previously designated through at least one subcarrier among a plurality of subcarriers corresponding to a guard carrier position of the legacy training signal and transmitting the non-legacy wireless communication based on the first signal, And may receive a non-legacy signaling field that signals information for the terminal.

Wherein the processor is configured to receive, when receiving the legacy signaling field, a plurality of subcarriers for transmitting the data of the legacy signaling field and a pilot signal among a plurality of subcarriers corresponding to positions of guard carriers of the legacy training signal, And can receive the first signal on one subcarrier.

Wherein the processor receives, when receiving the legacy signaling field, two subcarriers having the highest frequency among a plurality of subcarriers corresponding to a position of a left guard carrier of the legacy training signal with reference to 0 in a frequency band, The first signal can be received through two subcarriers having the lowest frequency among a plurality of subcarriers corresponding to the first subcarrier.

Wherein the processor receives the repeated legacy signaling field generated based on the legacy signaling field through the transceiver after receiving the legacy signaling field, and when receiving the repeated legacy signaling field, The second signal can be received through at least any one of the plurality of subcarriers corresponding to the position of the first subcarrier.

The first signal and the second signal may be the same.

Wherein the legacy signaling field includes length information indicating a duration of a non-legacy physical layer frame after a legacy signaling field, and the processor transmits the length information to a data size < RTI ID = 0.0 > Information other than the information indicating the duration of the non-legacy physical layer frame can be obtained through the remainder value obtained by dividing the non-legacy physical layer frame.

Wherein the processor indicates that information other than the information indicating the duration of the non-legacy physical layer frame indicates whether the non-legacy physical layer frame includes a first signaling field, and the first signaling field indicates that the wireless communication terminal has a plurality of When data is transmitted to a wireless communication terminal, information related to a plurality of wireless communication terminals can be signaled.

A method of operating a wireless communication terminal for wirelessly communicating according to an embodiment of the present invention includes: transmitting a legacy training signal for reception setting of a legacy signaling field including information decodable by a legacy wireless communication terminal; And transmitting a legacy signaling field, wherein the step of transmitting the legacy signaling field comprises the step of transmitting a legacy signaling field including at least one of a plurality of subcarriers corresponding to a guard carrier position of the legacy training signal, And transmitting the signal.

An embodiment of the present invention provides an efficient wireless communication method and a wireless communication terminal using a signaling field.

In particular, an embodiment of the present invention provides a wireless communication method and a wireless communication terminal supporting a plurality of signaling field formats.

1 shows a wireless LAN system according to an embodiment of the present invention.
2 shows a wireless LAN system according to another embodiment of the present invention.
3 is a block diagram illustrating a configuration of a station according to an embodiment of the present invention.
4 is a block diagram illustrating a configuration of an access point according to an embodiment of the present invention.
FIG. 5 schematically shows a process in which a station establishes a link with an access point according to an embodiment of the present invention.
FIG. 6 illustrates a structure of a physical layer frame and a legacy layer frame according to an embodiment of the present invention.
FIG. 7 shows a method of a legacy wireless communication terminal acquiring a duration of a physical layer frame based on L_LENGTH and a method of setting L_LENGTH according to an embodiment of the present invention.
FIG. 8 shows that a wireless communication terminal according to an embodiment of the present invention further transmits a subcarrier having a predetermined value to at least one of the L-LTF, the L-SIG field and the RL-SIG field.
FIG. 9 shows a structure of an HE-SIG-A field according to an embodiment of the present invention.
10 shows a structure of an HE-SIG-B field according to an embodiment of the present invention.
11 shows a structure of a HE-SIG-B field according to another embodiment of the present invention.
FIG. 12 shows a SIG-B structure of a physical layer frame when a wireless communication terminal according to an embodiment of the present invention transmits a physical layer frame to a plurality of wireless communication terminals.
FIG. 13 shows a method of signaling a discontinuous frequency band when a wireless communication terminal according to an embodiment of the present invention transmits data through a discontinuous frequency band in a frequency band having a bandwidth of 20 MHz.
FIG. 14 shows a data transmission method when a wireless communication terminal according to an embodiment of the present invention transmits data through a discontinuous frequency band.
FIG. 15 shows the structure of HE-SIG-A when the wireless communication terminal repeatedly transmits HE-SIG-A according to the embodiment of the present invention.
16 shows the operation of the wireless communication terminal according to the embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Also, when an element is referred to as "comprising ", it means that it can include other elements as well, without departing from the other elements unless specifically stated otherwise.

This application claims priority based on Korean Patent Application Nos. 10-2015-0108397 and 10-2015-0109759, and the embodiments and descriptions described in the above applications, which form the basis of priority, Are to be included in the detailed description of the present invention.

1 illustrates a wireless LAN system according to an embodiment of the present invention. A WLAN system includes one or more Basic Service Sets (BSSs), which represent a collection of devices that can successfully communicate and communicate with one another. In general, a BSS can be divided into an infrastructure BSS (infrastructure BSS) and an independent BSS (IBSS). FIG. 1 shows the infrastructure BSS.

1, an infrastructure BSS (BSS1, BSS2) includes one or more stations (STA1, STA2, STA3, STA_4, STA5), an access point (PCP / 1, PCP / AP-2), and a distribution system (DS) for connecting a plurality of access points (PCP / AP-1, PCP / AP-2).

A station (STA) is an arbitrary device including a medium access control (MAC) conforming to the IEEE 802.11 standard and a physical layer interface for a wireless medium, and is broadly referred to as a non-access point Non-AP) station as well as an access point (AP). In this specification, the term " terminal " may be used as a concept including both a station and a wireless LAN communication device such as an AP. The station for wireless communication includes a processor and a transmit / receive unit, and may further include a user interface unit, a display unit, and the like according to an embodiment. The processor may perform various processes for generating frames to be transmitted over the wireless network, processing frames received through the wireless network, and controlling other stations. The transmitting and receiving unit is functionally connected to the processor and transmits and receives a frame through the wireless network for the station.

An access point (AP) is an entity that provides access to a distribution system (DS) via a wireless medium for an associated station to an AP. In the infrastructure BSS, communication between non-AP stations is performed via an AP. However, when a direct link is established, direct communication is possible between non-AP stations. In the present invention, the AP is used as a concept including a PCP (Personal BSS Coordination Point), and broadly includes a central controller, a base station (BS), a node-B, a base transceiver system (BTS) Controller, and the like.

A plurality of infrastructure BSSs may be interconnected via a distribution system (DS). At this time, a plurality of BSSs connected through a distribution system is called an extended service set (ESS).

2 illustrates an independent BSS that is a wireless LAN system according to another embodiment of the present invention. In the embodiment of FIG. 2, the same or corresponding parts as those of the embodiment of FIG. 1 are not described.

Since the BSS 3 shown in FIG. 2 is an independent BSS and does not include an AP, all the stations STA6 and STA7 are not connected to the AP. An independent BSS is not allowed to connect to the distribution system and forms a self-contained network. In the independent BSS, each of the stations STA6 and STA7 can be directly connected to each other.

3 is a block diagram illustrating a configuration of a station 100 according to an embodiment of the present invention.

The station 100 according to the embodiment of the present invention may include a processor 110, a transceiver 120, a user interface 140, a display unit 150, and a memory 160 .

First, the transceiver unit 120 transmits and receives radio signals such as a WLAN physical layer frame, and may be embedded in the station 100 or externally. According to the embodiment, the transceiver 120 may include at least one transceiver module using different frequency bands. For example, the transceiver 120 may include transmit and receive modules of different frequency bands such as 2.4 GHz, 5 GHz, and 60 GHz. According to one embodiment, the station 100 may include a transmission / reception module using a frequency band of 6 GHz or more and a transmission / reception module using a frequency band of 6 GHz or less. Each of the transmission / reception modules can perform wireless communication with an AP or an external station according to a wireless LAN standard of a frequency band supported by the transmission / reception module. The transceiver unit 120 may operate only one transceiver module at a time or may operate a plurality of transceiver modules at the same time according to the performance and requirements of the station 100. [ When the station 100 includes a plurality of transmission / reception modules, each of the transmission / reception modules may be provided in an independent form, or a plurality of modules may be integrated into one chip.

Next, the user interface unit 140 includes various types of input / output means provided in the station 100. That is, the user interface unit 140 can receive user input using various input means, and the processor 110 can control the station 100 based on the received user input. Also, the user interface unit 140 may perform output based on the instruction of the processor 110 using various output means.

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

The processor 110 of the present invention can execute various commands or programs and process data inside the station 100. [ In addition, the processor 110 controls each unit of the above-described station 100, and can control data transmission / reception between the units. According to an embodiment of the present invention, the processor 110 may execute a program for connection of an AP stored in the memory 160, and may receive a communication setup message transmitted by the AP. In addition, the processor 110 can read information on the priority condition of the station 100 included in the communication setup message, and request a connection to the AP based on the information on the priority condition of the station 100. [ The processor 110 of the present invention may refer to a main control unit of the station 100 and may include a control unit for controlling a part of the station 100 such as the transmission and reception unit 120, It can also point to. That is, the processor 110 may be a modulator and / or a demodulator for modulating a radio signal transmitted / received from the transceiver 120. The processor 110 controls various operations of transmitting and receiving radio signals of the station 100 according to the embodiment of the present invention. Specific embodiments thereof will be described later.

The station 100 shown in FIG. 3 is a block diagram according to an embodiment of the present invention, and the blocks separately displayed are logically distinguishable from the elements of the device. Thus, the elements of the device described above can be mounted as one chip or as a plurality of chips depending on the design of the device. For example, the processor 110 and the transceiver 120 may be integrated into one chip or may be implemented as a separate chip. In some embodiments of the present invention, some components of the station 100, such as the user interface 140 and the display unit 150, may be optionally provided in the station 100.

4 is a block diagram showing the configuration of an AP 200 according to an embodiment of the present invention.

As shown, the AP 200 according to the embodiment of the present invention may include a processor 210, a transceiver 220, and a memory 260. In FIG. 4, the same or corresponding parts as those of the station 100 of FIG. 3 among the configurations of the AP 200 will be omitted.

Referring to FIG. 4, the AP 200 according to the present invention includes a transceiver 220 for operating a BSS in at least one frequency band. 3, the transceiver 220 of the AP 200 may also include a plurality of transceiver modules using different frequency bands. That is, the AP 200 according to the embodiment of the present invention may include two or more transmission / reception modules of different frequency bands, for example, 2.4 GHz, 5 GHz, and 60 GHz. Preferably, the AP 200 may include a transmission / reception module using a frequency band of 6 GHz or more and a transmission / reception module using a frequency band of 6 GHz or less. Each of the transmission / reception modules can perform wireless communication with the station according to the wireless LAN standard of the frequency band supported by the transmission / reception module. The transceiver 220 may operate only one transceiver module at a time or operate a plurality of transceiver modules at the same time according to the performance and requirements of the AP 200. [

Next, the memory 260 stores a control program used in the AP 200 and various data corresponding thereto. Such a control program may include an access program for managing the connection of the station. In addition, the processor 210 controls each unit of the AP 200, and can control data transmission / reception between the units. According to an embodiment of the present invention, processor 210 may execute a program for connection with a station stored in memory 260 and may transmit a communication setup message for one or more stations. At this time, the communication setup message may include information on the connection preference condition of each station. In addition, the processor 210 performs connection setup according to a connection request of the station. According to one embodiment, the processor 210 may be a modulator and / or a demodulator that modulates a radio signal transmitted / received from the transceiver 220. The processor 210 controls various operations of transmitting and receiving radio signals of the AP 200 according to an embodiment of the present invention. Specific embodiments thereof will be described later.

FIG. 5 schematically shows a process in which the STA establishes a link with an AP.

Referring to FIG. 5, the link between the STA 100 and the AP 200 is largely set through three steps of scanning, authentication, and association. First, the scanning step is a step in which the STA 100 acquires access information of a BSS operated by the AP 200. As a method for performing scanning, a passive scanning method in which information is acquired using only a beacon message (S101) periodically transmitted by the AP 200 and a passive scanning method in which the STA 100 transmits a probe request there is an active scanning method in which a probe request is transmitted (S103), a probe response is received from the AP (S105) and access information is acquired.

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

On the other hand, the 802.1X-based authentication step S111 and the IP address acquisition step S113 through DHCP can be performed. 5, the authentication server 300 is a server that processes STA 100 and 802.1X-based authentication, and may be physically coupled to the AP 200 or exist as a separate server.

When data is transmitted using Orthogonal Frequency Division Multiple Access (OFDMA) or Multi Input Multiple Output (MIMO), one of the wireless communication terminals can simultaneously transmit data to a plurality of wireless communication terminals. Also, any one of the wireless communication terminals can simultaneously receive data from a plurality of wireless communication terminals. When a wireless communication terminal transmits data to a plurality of wireless communication terminals, the wireless communication terminal must use a physical layer frame different from the physical layer frame used when data is transmitted to one wireless communication terminal. Specifically, a wireless communication terminal must signal information through a signaling field having a structure different from the signaling field structure of a physical layer frame used when data is transmitted to one wireless communication terminal.

In addition, when the wireless communication terminal performs long-range transmission, the wireless communication terminal must use a reliable physical layer frame structure.

In order to implement a new function and to signal information on a plurality of wireless communication terminals, the wireless communication terminal must use a signaling field structure capable of transmitting more information than the signaling field of the legacy physical layer frame.

A radio communication method using a signaling field of a physical layer frame capable of transmitting more information than a signaling field of a legacy physical layer frame and selectively using a physical layer frame structure according to various situations will be described with reference to FIG. 6 to FIG.

FIG. 6 shows a structure of a physical layer frame and a legacy physical layer frame according to an embodiment of the present invention.

FIG. 6A shows a structure of a legacy physical layer frame, and FIG. 6B shows a structure of a non-legacy physical layer frame according to an embodiment of the present invention.

A physical layer frame according to an embodiment of the present invention includes a legacy signaling field (L-SIG) for signaling information for a legacy wireless communication terminal. In addition, the physical layer frame according to an embodiment of the present invention includes a repeating legacy signaling field (RL-SIG) so that a wireless communication terminal can distinguish a non-legacy physical layer frame from a legacy physical layer frame. More specifically, when the received physical layer frame includes the repeating legacy signaling field, the non-legacy wireless communication terminal determines the received physical layer frame as a non-legacy physical layer frame without decoding the specific data of the received physical layer frame can do. At this time, the repetitive legacy signaling field RL-SIG may be generated based on the value of the legacy signaling field L-SIG. Specifically, the repeating legacy signaling field RL-SIG may be a signaling field having the same value as the legacy signaling field L-SIG. Also, the repeating legacy signaling field RL-SIG may be a modification of the legacy signaling field L-SIG.

In addition, the physical layer frame according to the embodiment of the present invention can be used in a case where the wireless communication terminal transmits data to any one of the wireless communication terminals and a HE-SIG-A Field. Specifically, the HE-SIG-A field includes a bandwidth of a physical layer frame, a BSS color, a number of HE-LTFs (Number_of_HE-LTF), and an MCS (Modulation and Coding Scheme) used for HE- And the like. The wireless communication terminal transmits the HE-SIG-A field through two OFDM symbols based on 64 FFT. The wireless communication terminal can transmit the HE-SIG-A field including the repeated field in the time domain through four OFDM symbols based on 64 FFTs. Particularly, in a long distance transmission requiring reliable transmission, the wireless communication terminal can transmit the HE-SIG-A field including the repeated field in the time domain through four OFDM symbols based on 64 FFTs.

The physical layer frame according to an embodiment of the present invention includes an HE-SIG-B field for signaling information on a plurality of wireless communication terminals. When the wireless communication terminal transmits data to one of the wireless communication terminals, the wireless communication terminal may not transmit the HE-SIG-B field.

The structure of the legacy signaling field (L-SIG) and the repetitive legacy signaling field (RL-SIG) in the specific embodiment may be as shown in Fig. 6 (c). At this time, the legacy signaling field L-SIG may include information on the transmission method of the data field indicated by the MPDU in FIG. 6 and length information indicating the length of the physical layer frame. Specifically, the legacy signaling field L-SIG may include an L_RATE field and an L_LENGTH field.

The L_RATE field indicates information on the transmission method of the data field. Specifically, the L_RATE field indicates the MCS used for transmission of the data field. For example, the L_RATE field may represent a combination of modulation methods such as BPSK / QPSK / 16-QAM / 64-QAM and code rates such as 1/2, 2/3, and 3/4. Specifically, the L_RATE field may indicate a transmission rate of any one of 6/9/12/18/24/36/48 / 54Mbps.

The L_LENGTH field signals the length of the physical layer frame. Specifically, the legacy wireless communication terminal can acquire the duration of the physical layer frame based on the L_LENGTH field. In a specific embodiment, the legacy wireless communication terminal may obtain the duration of the physical layer frame based on the L_LENGTH field and the L_RATE field. This will be described with reference to FIG.

FIG. 7 shows a method of a legacy wireless communication terminal acquiring a duration of a physical layer frame based on L_LENGTH and a method of setting L_LENGTH according to an embodiment of the present invention.

The wireless communication terminal communicates by OFDM symbols (hereinafter referred to as symbols). Therefore, when calculating the duration of the physical layer frame, the legacy wireless communication terminal calculates the legacy physical layer frame in units of length of a symbol to be transmitted. When the L_RATE field indicates 6 Mbps, the duration of one symbol modulated with 64 FFT is 4us. At this time, one symbol can transmit 3 bytes. The legacy wireless communication terminal divides the value of the L_LENGTH field by 3 bytes and converts the duration of the physical layer frame indicated by the L_LENGTH field into the number of symbols. The legacy wireless communication terminal adds the number of symbols corresponding to the duration of the SVC (service) field and the Tail field excluded from the value of the L_LENGTH field to the number of symbols corresponding to the value of the L_LENGTH field. The duration of the tail field and the SVC field can be treated as one symbol. The legacy wireless communication terminal multiplies the sum of the number of symbols obtained above by 4 us, which is the duration of one symbol, adds the L-SIG field located before the L_LENGTH field and the transmission time of L-STF and L-LTF, Obtain the total duration. Specifically, the legacy wireless communication terminal acquires the entire duration of the physical layer frame using the following equation

PPDU_DURATION = RXTIME = TXTIME = (1+ [L_LENGTH / 3]) x4 + 20

Here, [x] is a flooring operation representing the smallest natural number greater than x. Since the L_LENGTH field is a 12-bit field, the maximum value of the L_LENGTH field is 4095. According to the hypothesis, 5.484 ms is the maximum duration of the physical layer frame.

 The wireless communication terminal can set L_LENGTH based on an equation for acquiring the duration of the physical layer frame. The wireless communication terminal sets a value obtained by subtracting 20us, which is the transmission time of the L-STF and the L-LTF, from the L-SIG field located before the L_LENGTH field in the duration (TXTIME) of the physical layer frame as the number of symbols for transmitting the legacy signaling field Can be converted. Since the wireless communication terminal must transmit in symbol units, the wireless communication terminal must transmit a value obtained by subtracting 20sus, which is the transmission time of the L-STF and the L-LTF, from the L-SIG field located before the L_LENGTH field in the duration (TXTIME) of the physical layer frame, The field is divided by the duration of the symbol to be transmitted and then flooring is performed. The wireless communication terminal converts the number of acquired symbols into the size of the data. Specifically, the wireless communication terminal multiplies the number of acquired symbols by the size of data that can be transmitted by a symbol that transmits a legacy signaling field. Since the legacy wireless communication terminal subtracts the transmission time corresponding to the Tail field and the SVC field in the duration indicated by L_LENGTH, the wireless communication terminal subtracts the data size corresponding to the Tail field and the SVC field from the converted data size.

As described above, the duration of a symbol transmitted at a rate of 6 Mbps and modulated by 64 FFT is 4 us. The data transmitted at a rate of 6 Mbps and the data modulated with 64 FFT can be transmitted in 3 bytes. In addition, the data size corresponding to the Tail field and the SVC field is 3 bytes. Therefore, the wireless communication terminal can set the value of the L_LENGTH field according to the following equation.

L_LENGTH = [(TXTIME-20) / 4] x 3 - 3

Here, [x] is a flooring operation representing the smallest natural number greater than x.

As described above, the wireless communication terminal transmits data on a symbol-by-symbol basis. Therefore, the legacy wireless communication terminal converts the value of the L_LENGTH field into the duration of the physical layer frame based on the data size that can be transmitted by the symbol of the legacy signaling field. At this time, the legacy wireless communication terminal rounds the value of the L_LENGTH field after the data size that the symbol can transmit. Therefore, the legacy wireless communication terminal processes the value of the L_LENGTH field in the same data size range that the symbol can transmit. For example, when the data size of a symbol that can be transmitted by the symbol is 3 bytes, when the value of the L_LENGTH field and the duration value of the physical layer frame acquired when the value of the L_LENGTH field is 1201 is 1202 or 1203, The duration values of the physical layer frames are the same.

Therefore, the wireless communication terminal can signal information other than the duration of the physical layer frame through the value of the L_LENGTH field. Specifically, the wireless communication terminal can signal information other than the duration of the physical layer frame through the remaining value when the value of the L_LENGTH field is divided by the size of the data that can be transmitted by one symbol transmitting the L-SIG field. At this time, the information other than the duration of the physical layer frame through the value of the L_LENGTH field may be information on the format of the physical layer frame. More specifically, information other than the duration of the physical layer frame may indicate information on a cyclic prefix (CP) or a guard interval applied to the physical layer frame. In a specific embodiment, the wireless communication terminal may indicate the degree of CP length applied to the duration of the physical layer frame through the value of the L_LENGTH field. Specifically, if the data size that the symbol can transmit is 3 bytes, the wireless communication terminal can signal the CP length as follows.

The wireless communication terminal can signal that the CP duration of the physical layer frame is the shortest length by setting the remaining value obtained by dividing the value of the L_LENGTH field by 3 to 0. At this time. The physical layer frame may be a physical layer frame used in indoor. Also, the HE-SIG-A field may not include repeated field values in the time domain. The duration of the CP of the HE-SIG-A field is 0.8us, the duration of the CP of the HE-SIG-B field is 0.8us, and the duration of the CP of the signal modulated by 256FFTs after the HE- .

The wireless communication terminal can signal that the CP duration of the physical layer frame is medium length by setting the remainder obtained by dividing the value of the L_LENGTH field by 3 to 1. At this time. The physical layer frame may be a physical layer frame used both indoor (indoor) and outdoor (outdoor). Also, the HE-SIG-A field may contain repeated field values in the time domain or may not include repeated field values in the time domain. If the HE-SIG-A field does not contain a repeated field value in the time domain, the duration of the CP in the HE-SIG-A field is 0.8us, and the HE-SIG- If included, the duration of the CP in the HE-SIG-A field is greater than 0.8us. Also, the duration of the CP of the HE-SIG-B field is greater than 0.8us, and the duration of the CP of the signal modulated by 256 FFTs after the HE-STF may be 1.6us.

The wireless communication terminal can signal that the CP duration of the physical layer frame is the longest length by setting the remainder obtained by dividing the value of the L_LENGTH field by 3 to 2. At this time. The physical layer frame may be a physical layer frame used in an outdoor environment. Also, the HE-SIG-A field contains a repeated field value in the time domain. The duration of the CP in the HE-SIG-A field is 0.8us. Also, the duration of the CP of the HE-SIG-B field is greater than 0.8us, and the duration of the CP of the signal modulated with 256 FFTs after the HE-STF may be 3.2us.

FIG. 8 shows that a wireless communication terminal according to an embodiment of the present invention further transmits a subcarrier having a predetermined value to at least one of L-LTF, L-SIG, and RL-SIG.

As in the embodiment of FIG. 8 (a), the wireless communication terminal modulates the signal based on 64 FFT and 256 FFT. L-LTF, L-SIG field, RL-SIG field, HE-SIG-A and HE-SIG-B based on 64 FFT so that the legacy wireless communication terminal can decode Modulate the field. The wireless communication terminal modulates a signal transmitted after the HE-SIG-B field based on 256 FFT.

When modulating a signal based on a 64 FFT, the wireless communication terminal transmits 64 subcarriers. For convenience of explanation, 64 subcarriers are divided into indexes of -32 to 31. The wireless communication terminal uses six left subcarriers whose indexes are from -32 to -27 and five subcarriers whose indexes are from 27 to 31 as guard carriers. In addition, the radio communication terminal uses one central subcarrier having an index of 0 as a DC (0) subcarrier.

The wireless communication terminal transmits data and pilot signals through 52 subcarriers excluding guard carriers and DC subcarriers. Specifically, the wireless communication terminal transmits a pilot signal through subcarriers corresponding to indexes -21, -7, 7, and 21, and transmits data through the remaining 48 subcarriers.

When the wireless communication terminal uses some of the six subcarriers corresponding to the guard carrier position for data transmission, a larger amount of information can be transmitted through the signaling field. Specifically, when the wireless communication terminal transmits a signaling field as in the embodiment of FIG. 8 (e), a larger amount of information can be transmitted through the signaling field. However, since the legacy wireless communication terminal has to decode the L-SIG, the wireless communication terminal can not use some of the six subcarriers corresponding to the guard carrier position of the L-SIG field for data transmission of the L-SIG field. Since the wireless communication terminal transmits the RL-SIG field based on the L-SIG field, some of the six subcarriers corresponding to the guard carrier position of the RL-SIG field can not be used for data transmission of the RL-SIG field.

When transmitting a non-legacy signaling field for signaling information for a non-legacy wireless communication terminal, the wireless communication terminal does not consider compatibility with a legacy wireless communication terminal. At this time, the non-legacy signaling field includes an HE-SIG-A field and a HE-SIG-B field. Therefore, the wireless communication terminal can transmit the non-legacy signaling field by using a part of the six subcarriers corresponding to the position of the guard carrier in the data transmission, when transmitting the legacy signaling field and the legacy signaling field. At this time, the legacy signaling field may include the L-SIG field described above. In addition, the training signal for the legacy signaling field may include at least one of L-STF and L-LTF. Specifically, the wireless communication terminal uses four left subcarriers corresponding to the indices -32 to -29 and three right subcarriers corresponding to the indices 29 to 31 as guard carriers, and subcarriers corresponding to the index 0 as DC Can be used to transmit the non-legacy signaling field via 52 subcarriers.

The wireless communication terminal must estimate the channel state in order to receive the signal. For this purpose, the wireless communication terminal transmitting the signal transmits the L-LTF. The wireless communication terminal receiving the physical layer frame estimates the channel state based on the L-LTF, and receives the physical layer frame based on the estimated channel state. When a wireless communication terminal transmits a non-legacy signaling field using a part of six subcarriers corresponding to a guard carrier position of an L-STF, the wireless communication terminal transmits a non-legacy signaling field to a subcarrier corresponding to a guard carrier position of the L- The channel estimation can not be performed and the signal can not be received stably. In order to prevent this, when transmitting at least one of the L-LTF, the L-SIG field, and the RL-SIG field, the wireless communication terminal transmits at least one of a plurality of subcarriers corresponding to the guard carrier position of the L- A predetermined signal can be transmitted.

Specifically, when transmitting an L-LTF, a wireless communication terminal transmits a plurality of subcarriers for transmitting an L-STF signal among a plurality of subcarriers corresponding to a guard carrier position of the L-STF and at least one subcarrier A predetermined signal can be transmitted. In a specific embodiment, when transmitting the L-LTF, the wireless communication terminal transmits the L-STF with the highest frequency among the plurality of subcarriers corresponding to the position of the left guard carrier of the L-STF and the position of the right guard carrier of the L- It is possible to transmit a signal designated in advance to two subcarriers having the lowest frequency among a plurality of corresponding subcarriers. For example, the wireless communication terminal can transmit a signal as in the embodiment of Fig. 8 (b). At this time, the predetermined signal may be a signal sequence that can minimize the peak to average power ratio (PAPR) of the L-LTF. Specifically, the predetermined signal may be 1, 1, -1, and -1 according to the index order. When a wireless communication terminal transmits a predetermined signal through a part of a plurality of subcarriers corresponding to the guard carrier position of the L-STF when transmitting the L-LTF, the wireless communication terminal transmits the L-SIG and RL-SIG fields It is possible to transmit additional data through a subcarrier on which a predetermined signal is transmitted while transmitting. However, when a legacy wireless communication terminal receives an L-LTF, interference due to a previously transmitted predetermined signal may occur.

In another specific embodiment, when transmitting an L-SIG field, the wireless communication terminal may include a plurality of sub-carriers for transmitting data and pilot signals of the L-SIG field among a plurality of subcarriers corresponding to positions of guard carriers of the legacy training signal It is possible to transmit a signal designated in advance to at least one of the subcarriers continuous with the carrier. Specifically, when the L-SIG is transmitted, the wireless communication terminal selects one of the subcarriers having the highest frequency among the plurality of subcarriers corresponding to the position of the left guard carrier of the legacy training signal and the position of the right guard carrier of the legacy training signal A signal previously assigned to two subcarriers having the lowest frequency among a plurality of subcarriers can be transmitted. For example, the wireless communication terminal can transmit a signal as in the embodiment of Fig. 8 (c). At this time, the predetermined signal may be a signal sequence that can minimize the PAPR (Peak to Average Power Ratio) of the L-SIG. Specifically, the predetermined signal may be 1, 1, -1, and -1 according to the index order. When a wireless communication terminal transmits a predetermined signal through a part of a plurality of subcarriers corresponding to a guard carrier position of a legacy training signal when the L-SIG is transmitted, the legacy wireless communication terminal has no influence on reception of the legacy training signal I can not. However, when a wireless communication terminal transmits a predetermined signal through a part of a plurality of subcarriers corresponding to a guard carrier position of a legacy training signal when transmitting an L-SIG, the RL-SIG The efficiency of auto detection using a field can be reduced.

In another specific embodiment, when transmitting the RL-SIG field, the wireless communication terminal may include a plurality of sub-carriers for transmitting data and pilot signals of the RL-SIG field among a plurality of subcarriers corresponding to the guard carrier position of the legacy training signal It is possible to transmit a signal designated in advance to at least one of the subcarriers continuous with the carrier. When transmitting the RL-SIG field, the wireless communication terminal transmits two (2) subcarriers having the highest frequency among the plurality of subcarriers corresponding to the position of the left guard carrier of the legacy training signal and a plurality Of the subcarriers having the lowest frequency can be transmitted. Specifically, the wireless communication terminal can transmit a signal as in the embodiment of FIG. 8 (d). At this time, the predetermined signal may be a signal sequence that can minimize the PAPR (Peak to Average Power Ratio) of the L-SIG. Specifically, the predetermined signal may be 1, 1, -1, and -1 according to the index order. When a wireless communication terminal transmits a predetermined signal through a part of a plurality of subcarriers corresponding to a guard carrier position of a legacy training signal when transmitting an RL-SIG field, the legacy training signal of the legacy wireless communication terminal and the L- It may not affect reception. However, when a wireless communication terminal transmits a predetermined signal through a part of a plurality of subcarriers corresponding to a guard carrier position of a legacy training signal when transmitting an RL-SIG field, an auto detection using an RL-SIG field detection efficiency.

In another specific embodiment, when transmitting the L-SIG and RL-SIG fields, the wireless communication terminal transmits the data and pilot signal of the RL-SIG field among the plurality of subcarriers corresponding to the position of the guard carrier of the legacy training signal And a predetermined signal can be transmitted to at least any one of the subcarriers consecutive with the plurality of subcarriers to be transmitted. Specifically, when transmitting the L-SIG and RL-SIG fields, the wireless communication terminal transmits two subcarriers having the highest frequency among the plurality of subcarriers corresponding to the position of the left guard carrier of the legacy training signal and the right guard carrier of the legacy training signal A signal previously assigned to two subcarriers having the lowest frequency among the plurality of subcarriers corresponding to the positions of " 1 " At this time, the predetermined signal transmitted by the wireless communication terminal through the L-SIG may be different from the predetermined signal transmitted through the RL-SIG field. The wireless communication terminal transmits any one of a predetermined signal transmitted through the L-SIG and a plurality of predetermined signals transmitted through the RL-SIG field, and signals additional information other than the L-SIG field data .

At this time, the additional information includes a new transmission mode of the physical layer frame, information for symbol configuration, information about the structure of the physical layer frame, information for performing CCA, information for decoding the non-legacy signaling field, And information for a wireless communication terminal.

Specifically, the new transmission mode of the physical layer frame may include a transmission mode for long range transmission. In a specific embodiment, the transmission mode for long distance transmission may indicate that a new structure of physical layer frame for long distance transmission is used. In addition, the information for symbol configuration may include at least one of OFDM symbol synchronization, FFT size, and CP length. The information on the structure of the physical layer frame may include at least one of the number of transmission symbols of the STF / LTF, the transmission order, the type of the signaling field, the length of the signaling field, and the analysis method of the signaling field. In addition, the information for performing the CCA may include at least one of BSS color, BSS color application, and offset value for the threshold value in the SD / ED to be used in CCA.

The information for decoding the non-legacy signaling field may specifically be information for decoding the TXOP duration indicated by the non-legacy signaling field. Specifically, the information for decoding the non-legacy signaling field may be the granularity of the TXOP duration indicated by the non-legacy signaling field. In another specific embodiment, the information for decoding the non-legacy signaling field may be an offset value of the TXOP duration indicated by the non-legacy signaling field.

The information for a wireless communication terminal belonging to another BSS may be information indicating a relative position of a frequency band in which the RL-SIG field is transmitted. At this time, the relative position may indicate that the frequency band is high or low. Further, when the 80 MHz + 80 MHz frequency band is used, the relative position may indicate either the relatively high frequency band of 80 MHz or the 80 MHz frequency band which is relatively low.

A wireless communication terminal belonging to another BSS may have to decode the value of the non-legacy signaling field in order to perform Spatial Reuse (SR). At this time, a wireless communication terminal belonging to another BSS can not know a relative position of a frequency band through which a signal is transmitted, and when a non-legacy signaling field indicates information on a plurality of frequency bands, a non-legacy signaling It can not be determined whether the value of the field should be acquired. Therefore, the wireless communication terminal can transmit information indicating the relative position of the frequency band through which the RL-SIG field is transmitted through the RL-SIG field. At this time, the wireless communication terminal belonging to another BSS can determine the relative position of the frequency band in which the RL-SIG field is transmitted based on the RL-SIG field. A wireless communication terminal belonging to another BSS can decode the non-legacy signaling field based on the relative position. For example, a wireless communication terminal belonging to another BSS may decode information on an SR (Spatial Reuse) indicated by a non-legacy signaling field based on a relative position.

When a predetermined signal is transmitted according to the above-described embodiment, the wireless communication terminal receiving the physical layer frame estimates the state of the channel based on a predetermined signal. The wireless communication terminal receives the non-legacy signaling field based on the state of the estimated channel.

In addition, the wireless communication terminal can transmit the predetermined signal described in FIG. 8 on a 20 MHz frequency band basis.

FIG. 9 shows a structure of an HE-SIG-A field according to an embodiment of the present invention.

As described above, the physical layer frame according to the embodiment of the present invention is used when the wireless communication terminal transmits data to any one wireless communication terminal and when the data is transmitted to a plurality of wireless communication terminals, the HE- SIG-A < / RTI > Specifically, the HE-SIG-A field includes at least one of a bandwidth of a physical layer frame, a BSS color, the number of HE-LTFs (Number_of_HE-LTF), and MCS information used for HE-SIG-B field transmission One can be included.

Also, the wireless communication terminal can transmit the HE-SIG-A field including the repeated field in the time domain through four symbols based on 64 FFT. In particular, in a long distance transmission requiring reliable transmission, the wireless communication terminal can transmit the HE-SIG-A field including the repeated fields in the time domain through four symbols based on 64 FFTs.

In addition, when the wireless communication terminal transmits data to a plurality of wireless communication terminals, the wireless communication terminal can signal information on a plurality of wireless communication terminals through the HE-SIG-B field. When the wireless communication terminal transmits data to one of the wireless communication terminals, it may not transmit the HE-SIG-B.

Therefore, the wireless communication terminal needs to signal on the format of the physical layer frame. When the wireless communication terminal signals the format of the physical layer frame through the field included in the HE-SIG-A, the HE-SIG-A field of the wireless communication terminal receiving the physical layer frame is decoded, The format can be judged. Therefore, when the wireless communication terminal signals the format of the physical layer frame through the field included in the HE-SIG-A, the decoding operation burden of the wireless communication terminal receiving the physical layer frame can be increased. Therefore, there is a need for a method of signaling the format of the physical layer frame through a signal transmitted by the wireless communication terminal before the HE-SIG-A field transmission.

Specifically, the wireless communication terminal can signal whether the HE-SIG-A field includes a repeated field in the time domain through the value of the L_LENGTH field of the L-SIG field described above. Specifically, when the value of the L_LENGTH field is divided by the size of data that can be transmitted by one symbol transmitting the L-SIG field, the wireless communication terminal determines whether the HE-SIG-A field is repeated in the time domain Or not.

Also, the wireless communication terminal can signal whether the physical layer frame includes the HE-SIG-B field through the value of the L_LENGTH field. Specifically, the wireless communication terminal determines whether the physical layer frame includes the HE-SIG-B field through the remaining value when the value of the L_LENGTH field is divided by the size of data that can be transmitted by one symbol transmitting the L-SIG field Can be signaled.

Also, the wireless communication terminal can signal whether the physical layer frame includes the HE-SIG-B field through the modulation method of the first symbol and the second symbol transmitting the HE-SIG-A field. At this time, the wireless communication terminal modulates the first symbol, which transmits the HE-SIG-A field, to BPSK to distinguish it from the legacy physical layer frame. Accordingly, the wireless communication terminal can signal whether the physical layer frame includes the HE-SIG-B field through the modulation method of the second symbol for transmitting the HE-SIG-A field. Specifically, the wireless communication terminal may signal whether the physical layer frame includes the HE-SIG-B field according to whether the second symbol transmitting the HE-SIG-A field is modulated to BPSK or QBPSK. For example, the wireless communication terminal signals the fact that the physical layer frame includes the HE-SIG-B field by modulating the second symbol transmitting the HE-SIG-A field to BPSK, and transmits the HE-SIG- To the QBPSK to signal that the physical layer frame does not include the HE-SIG-B field. In a specific embodiment, the wireless communication terminal signals the fact that the physical layer frame includes an HE-SIG-B field by modulating a second symbol transmitting the HE-SIG-A field to QBPSK, The second symbol to be transmitted may be modulated with BPSK to signal that the physical layer frame does not include the HE-SIG-B field.

In another specific embodiment, the wireless communication terminal transmits the L-SIG field and the RL-SIG field and transmits the HE-SIG-B field of the physical layer frame through a part of a plurality of subcarriers corresponding to guard carriers of the L- May be included.

In another specific embodiment, the wireless communication terminal signals the HE-SIG-A field including the repeated field in the time domain without additional signaling to indicate that the physical layer frame does not include the HE-SIG-B field .

10 to 11 show the structure of an HE-SIG-B field according to an embodiment of the present invention.

The HE-SIG-B field indicates information on a plurality of wireless communication terminals when one of the wireless communication terminals transmits data to the plurality of wireless communication terminals as described above. The HE-SIG-B field includes common information common to a plurality of wireless communication terminals and user specific information related to any one of the plurality of wireless communication terminals. At this time, the user characteristic information includes information on resource unit allocation, a sub-band index indicating a sub-frequency band, a resource unit size, and an MCS for transmitting data. And information on the number of space time streams (NSTS) used to transmit the data. Specifically, HE-SIG-B can have the same structure as in the embodiment of Fig. 10 (b).

When the wireless communication terminal transmits data through a frequency band having a bandwidth greater than 20 MHz, the wireless communication terminal transmits the same L-SIG field, RL-SIG field, and HE-SIG-A field every 20 MHz.

Also, when a wireless communication terminal transmits a physical layer frame through a frequency band having a bandwidth of 40 MHz, the wireless communication terminal can transmit different HE-SIG-B fields for each 20 MHz bandwidth. When a wireless communication terminal transmits a physical layer frame through a frequency band having a bandwidth of 80 MHz or 160 MHz, the wireless communication terminal can repeatedly transmit two different HE-SIG-B fields each having a 20 MHz bandwidth every 40 MHz. Specifically, when a wireless communication terminal transmits a physical layer frame through a frequency band having a bandwidth of 80 MHz, the wireless communication terminal transmits a first HE-SIG-B field in a frequency band having a first 20 MHz bandwidth, And may transmit a second HE-SIG-B field in a frequency band having a bandwidth. At this time, the wireless communication terminal can transmit the first HE-SIG-B field in the frequency band having the third 20MHz bandwidth and the second HE-SIG-B field in the frequency band having the fourth 20MHz bandwidth. Specifically, the wireless communication terminal can transmit a physical layer frame having the same structure as in the embodiment of FIG. 10 (a). In another specific embodiment, when a wireless communication terminal transmits a physical layer frame through a frequency band having a bandwidth of 160 MHz, the wireless communication terminal transmits a first HE-SIG-B field in a frequency band having a first 20 MHz bandwidth , And a second HE-SIG-B field in a frequency band having a second 20 MHz bandwidth. At this time, the wireless communication terminal transmits the first HE-SIG-B field in the frequency band having the third, fifth, seventh 20MHz bandwidth, and transmits the first HE-SIG-B field in the frequency band having the fourth, sixth, HE-SIG-B field.

Therefore, each of a plurality of wireless communication terminals that receive data from any one of the wireless communication terminals should find out which frequency band the transmitted HE-SIG-B field contains information corresponding to each of the plurality of wireless communication terminals.

To this end, the wireless communication terminal can simultaneously decode different frequency bands having a bandwidth of 20 MHz using two decoders. Specifically, the wireless communication terminal can decode the HE-SIG-A field from the L-STF through one decoder and decode the HE-SIG-B field through the two decoders. However, this method can increase the computation burden of the wireless communication terminal receiving the physical layer frame.

In another specific embodiment, the wireless communication terminal may indicate a wireless communication terminal corresponding to information included in the HE-SIG-B field through CRC masking. Specifically, the wireless communication terminal generates a CRC value of the HE-SIG-B field and may mask the identifier with the identifier of the wireless communication terminal corresponding to the information included in the HE-SIG-B field. At this time, the identifier of the wireless communication terminal may be the MAC ID of the wireless communication terminal. The identifier of the wireless communication terminal may be a group identifier (Group ID) indicating a group including the wireless communication terminal. In addition, masking can represent bit operations such as XOR operations.

At this time, the wireless communication terminal receiving the physical layer frame generates a CRC with the value of the HE-SIG-B field, and generates a CRC including the value obtained by masking the generated CRC with the identifier of the wireless communication terminal, Field to determine whether the HE-SIG-B field contains information about the wireless communication terminal. Specifically, the wireless communication terminal generates a CRC with the value of the HE-SIG-B field, and when the value obtained by masking the generated CRC with the identifier of the wireless communication terminal and the value of the CRC field included in the HE-SIG-B field are the same , It can be determined that the corresponding HE-SIG-B field includes information on the wireless communication terminal. The operation of the specific wireless communication terminal may be the same as the flowchart of Fig. 11 (a). The wireless communication terminal can quickly perform the CRC calculation and the masking operation so that it is possible to quickly determine in which frequency band the HE-SIG-B field includes information on the wireless communication terminal.

In addition, when the wireless communication terminal performs long-distance data transmission, the wireless communication terminal must increase the reliability of HE-SIG-B field transmission. For this, the wireless communication terminal can transmit the HE-SIG-B field as in the following embodiments.

Specifically, the wireless communication terminal can transmit a HE-SIG-B field including a repeated field value in the time domain. Thus, the wireless communication terminal can increase the transmission probability of the HE-SIG-B field. However, since the wireless communication terminal transmits repeated data in the time domain, the transmission efficiency of the wireless communication terminal may deteriorate.

In another specific embodiment, the wireless communication terminal may use a CP with a longer duration than a normal transmission in a long haul transmission. For example, the wireless communication terminal can use 1.2us, 1.6us, or 3.2us, which is larger than 0.8us, as the size of the CP duration. Also, the wireless communication terminal can signal the CP length through the embodiment described in FIG.

In another specific embodiment, the wireless communication terminal can transmit a repeated field at a bit level. Specifically, the wireless communication terminal repeatedly transmits the common information (Common Info) of the HE-SIG-B field at the bit level and repeatedly transmits the user specific information about the wireless communication terminal located at a long distance have. In a specific embodiment, the wireless communication terminal may transmit the HE-SIG-B field as in the embodiment of FIG. 11 (b).

In Figs. 10 to 11, it is assumed that the frequency bandwidth used by one of the wireless communication terminals while transmitting data to a plurality of wireless communication terminals is one of 20 MHz, 40 MHz, 80 MHz, and 160 MHz. According to a specific embodiment, the size of the frequency bandwidth used by one of the wireless communication terminals while transmitting data to the plurality of wireless communication terminals may be varied.

FIG. 12 shows a SIG-B structure of a physical layer frame when a wireless communication terminal according to an embodiment of the present invention transmits a physical layer frame to a plurality of wireless communication terminals.

11, when a wireless communication terminal transmits a physical layer frame through a frequency band having a bandwidth of 40 MHz, the wireless communication terminal can transmit different HE-SIG-B fields for each 20 MHz bandwidth. Also, when a wireless communication terminal transmits a physical layer frame through a frequency band having a bandwidth of 80 MHz or 160 MHz, the wireless communication terminal can repeatedly transmit two different HE-SIG-B fields each having a 20 MHz bandwidth every 40 MHz .

At this time, the HE-SIG-B field includes common information (Common Info) common to a plurality of wireless communication terminals and user characteristic information (User Specific Info) related to any one of the wireless communication terminals do. The user characteristic information may include information about a wireless communication terminal receiving data through a frequency band in which the HE-SIG-B field containing the user characteristic information is transmitted. Since the HE-SIG-B field having a frequency band having a bandwidth of 20 MHz is repeatedly transmitted every 40 MHz, the user characteristic information is transmitted to a wireless communication terminal that receives data through all frequency bands through which the same HE-SIG- And the like.

The wireless communication terminal receiving the physical layer frame can acquire the information on the resource unit allocation based on the common information and acquire the user characteristic information on the wireless communication terminal based on the information on the resource unit allocation. For example, the wireless communication terminal receiving the physical layer frame determines, based on the common information, which frequency band the user characteristic information about the wireless communication terminal is located in the HE-SIG-B field.

However, when data transmission to any one of the wireless communication terminals is performed through a discontinuous frequency band, the wireless communication terminal must determine a discontinuous frequency band in which the wireless communication terminal transmits data to be received. Accordingly, the user characteristic information may include information indicating a frequency band in which data to be received by the wireless communication terminal corresponding to the user characteristic information is transmitted. Specifically, the user characteristic information may include a sub-frequency band index indicating a frequency band in which data to be received by the wireless communication terminal corresponding to the user characteristic information is transmitted. At this time, the HE-SIG-B field may include a plurality of sub-fields indicating user characteristic information. The plurality of sub-fields may be divided into frequency bands having a bandwidth of 20 MHz and wireless communication terminals. For example, when an access point (AP) transmits data for a first station through a first frequency band and a third frequency band with a 20 MHz frequency bandwidth, the HE- The SIG-B field may include two sub-fields indicating information for the first station. When a frequency band having a bandwidth of 20 MHz and a wireless communication terminal are distinguished, information on a wireless communication terminal is transmitted in duplicate to a plurality of sub-fields. Therefore, the transmission efficiency is lowered.

In yet another specific embodiment, the sub-fields may be identified by wireless communication terminals. For example, when an access point (AP) transmits data for a first station through a first frequency band and a third frequency band with a 20 MHz frequency bandwidth, the HE- The SIG-B field may include one sub-field indicating information for the first station. At this time, the length of the sub-field may be variable according to the change of the sub-frequency band. If the length of the sub-field is variable, the length of the sub-field must be signaled separately. In order to prevent this, a wireless communication terminal transmitting a physical layer frame may display a sub-frequency band index as a fixed length field such as a bit map. A specific embodiment showing sub-fields of the user characteristic information will be described with reference to Figs. 12 (a), 12 (b) -1 and 12 (b) -2.

In the embodiment of FIG. 12 (a), the access point AP includes a first station A, a second station B, a third station C, a fourth station D, and a fifth station E ). ≪ / RTI > The access point AP transmits data to the first station A and the second station B through a first frequency band (1 ^st 20 MHz) having a bandwidth of 20 MHz. The access point AP transmits data to the third station C through the second frequency band (2 ^nd 20 MHz) having a bandwidth of 20 MHz. The access point AP transmits data to the first station A through a third frequency band (3 ^rd 20 MHz) having a bandwidth of 20 MHz. The access point AP transmits data to the fourth station D and the fifth station E through a fourth frequency band (4 ^th 20 MHz) having a bandwidth of 20 MHz.

The first HE-SIG-B field transmitted through the first frequency band (1 ^st 20 MHz) and the third frequency band (3 ^rd 20 MHz) includes information about the first station (A) and the second station (B) do. The second HE-SIG-B field transmitted through the second frequency band (2 ^nd 20 MHz) and the fourth frequency band (4 ^th 20 MHz) includes the third station (C), the fourth station (D) (D).

FIG. 12 (b) -1 shows a case where a plurality of sub-fields indicating user characteristic information are divided into frequency bands having a bandwidth of 20 MHz and wireless communication terminals. The access point AP transmits information about the first station A to a sub-field indicating a sub-frequency band index allocated to the first station A in the first frequency band (1 ^st 20 MHz) Field indicative of the sub-frequency index assigned to the first station A at the base station (3 ^rd 20 MHz).

FIG. 12 (b) -2 shows a case where a plurality of sub-fields indicating user characteristic information are classified into wireless communication terminals. The access point (AP) signals information on the first station (A) through one sub-field. At this time, the access point (AP) can signal the sub-frequency band index to a fixed length field such as a bitmap.

When data to be received by any one of the wireless communication terminals is transmitted through a frequency band signaled by different HE-SIG-B fields, different HE-SIG-B fields include information about wireless communication terminals . In the embodiment of Fig. 12 (c), the access point AP transmits data to the first station A in the first frequency band (1 ^st 20 MHz) and the second frequency band (2 ^nd 20 MHz). At this time, a first HE-SIG-B field indicating information on a wireless communication terminal to receive data through the first frequency band (1 ^st 20 MHz) and the third frequency band (3 ^rd 20 MHz) Lt; / RTI > Also, a first HE-SIG-B field indicating information on a wireless communication terminal to receive data through a second frequency band (2 ^nd 20 MHz) and a fourth frequency band (4 ^th 20 MHz) Lt; / RTI >

FIG. 13 shows a method of signaling a discontinuous frequency band when a wireless communication terminal according to an embodiment of the present invention transmits data through a discontinuous frequency band in a frequency band having a bandwidth of 20 MHz.

The wireless communication terminal can transmit data to any one of the wireless communication terminals through a discontinuous frequency band within a frequency band having a bandwidth of 20 MHz. At this time, the characteristic information of the HE-SIG-B field may include a sub-frequency band index indicating a sub-frequency band within a frequency band having a 20 MHz bandwidth. At this time, the HE-SIG-B field may include a plurality of sub-fields indicating user characteristic information. The plurality of sub-fields may be divided into sub-frequency bands within a frequency band having a bandwidth of 20 MHz and wireless communication terminals

13, the access point AP transmits data to the first station A via A1 and A2 which are sub-frequency bands of the first frequency band (1 ^st 20 MHz, 1-00). The access point AP transmits data to the first station A through A3 which is the sub-frequency band of the second frequency band (2 ^nd 20 MHz, 2-00). The access point AP transmits data to the first station A via A4 which is the sub-frequency band of the third frequency band (3 ^rd 20 MHz, 1-01). The access point AP transmits data to the first station A through A5 which is the sub-frequency band of the fourth frequency band (4 ^th 20 MHz, 2-01).

At this time, the user characteristic information of the first HE-SIG-B field includes a first station and a sub-field indicating information on the sub-frequency band A1, a sub-field indicating information on the first station and the sub- And a sub-field indicating information about the first station and the sub-frequency band A4. The user characteristic information of the second HE-SIG-B field includes a sub-field indicating information on the first station and the sub-frequency band A3 and a sub-field indicating information on the first station and the sub-frequency band A5 do. At this time, there is a problem in that a wireless communication terminal that transmits a physical ray frame transmits data within a frequency band having a bandwidth of 20 MHz. This will be described with reference to FIG.

FIG. 14 shows a data transmission method when a wireless communication terminal according to an embodiment of the present invention transmits data through a discontinuous frequency band.

As described above, the wireless communication terminal can transmit data for any one wireless communication terminal through a discrete frequency band. At this time, the wireless communication terminal can transmit the divided data through each of the plurality of sub-frequency bands included in the discontinuous frequency band. At this time, the divided data can not be decoded as individual data, and the divided data can be integrated and decoded. Accordingly, the wireless communication terminal receiving the physical layer frame receives a plurality of divided data through a plurality of sub-frequency bands included in the discontinuous frequency band. The wireless communication terminal integrates a plurality of divided data to decode the data. At this time, the data may be aggregated MAC Protocol Data Unit (A-MPDU). In the embodiment of FIG. 14 (a), the wireless communication terminal divides and transmits one A-MPDU through five sub-frequency bands A1 to A5. The wireless communication terminal receiving the physical layer frame combines the divided data transmitted through each of the five sub-frequency bands A1-A5 to generate an A-MDPU and decodes the A-MDPU. In this way, when the wireless communication terminal transmits divided data through each of a plurality of sub-frequency bands included in the discontinuous frequency band, the header information necessary for data transmission can be minimized and the transmission efficiency can be increased. However, when the wireless communication terminal receiving the physical layer frame fails to receive the divided data transmitted through any sub-frequency band, the wireless communication terminal receiving the data can not decode the entire data.

In another specific embodiment, the wireless communication terminal can transmit independent individual data over each of a plurality of sub-frequency bands. At this time, independent individual data can be decoded as individual data. Therefore, the wireless communication terminal receiving the physical layer frame receives a plurality of individual data through a plurality of sub-frequency bands included in the discontinuous frequency band. The wireless communication terminal individually decodes a plurality of individual data. At this time, each of the individual data may be an Aggregated MAC Protocol Data Unit (MPDU). 14 (b), the wireless communication terminal transmits five A-MPDUs (A-MPDU1-A-MPDU2) through five sub-frequency bands A1 to A5, respectively. The wireless communication terminal receiving the physical layer frame receives each of five A-MPDUs (A-MPDU1-A-MPDU2) through each of the five sub-frequency bands A1-A5. The wireless communication terminal decodes each of the received five A-MPDUs (A-MPDU1-A-MPDU2). As described above, when the wireless communication terminal transmits independent individual data through each of a plurality of sub-frequency bands included in the discontinuous frequency band, the wireless communication terminal receiving the physical layer frame transmits the sub- Even if the individual data to be transmitted is not received, the remaining individual data can be decoded. However, the number of headers necessary for data transmission increases, which may lower the transmission efficiency.

FIG. 15 shows the structure of HE-SIG-A when the wireless communication terminal repeatedly transmits HE-SIG-A according to the embodiment of the present invention.

As described above, when transmitting the HE-SIG-A field, the wireless communication terminal can repeatedly transmit the same field in the time domain. The wireless communication terminal transmits the HE-SIG-A including the repeated field in the time domain through four symbols, and transmits the general HE-SIG-A field through the two symbols. A generic HE-SIG-A field refers to a HE-SIG-A field that does not contain repeated fields in the time domain. When the wireless communication terminal transmits the HE-SIG-A including the repeated field in the time domain, it is a problem how the wireless communication terminal applies the CP.

The wireless communication terminal can apply the CP used for the normal HE-SIG-A field transmission before the subfield indicating the data of the HE-SIG-A field and before the repetition subfield in which the corresponding subfield is repeated. Specifically, as shown in FIG. 15A, the same CP is repeated before the repetitive subfields RA1 and RA2 in which the subfields representing the data of the subfields A1 and A2 representing the data of the HE-SIG-A field are repeated Lt; / RTI > In a specific embodiment, the duration of the CP may be 0.8us. When the HE-SIG-A includes a subfield and a repetitive subfield, the wireless communication terminal receiving the physical layer frame receives the subfield and the repeating subfield of the HE-SIG-A by soft combining There are advantages to be able to. However, in an environment with large delay dispersion, a CP with a duration of 0.8us which is not long can not adequately cancel the delay dispersion. Therefore, a problem may occur that the wireless communication terminal can not receive the HE-SIG-A well.

The wireless communication terminal can apply a CP used for a general HE-SIG-A field transmission after the subfield indicating the data of the HE-SIG-A field and after the repetition subfield in which the corresponding subfield is repeated. Specifically, as shown in FIG. 15 (b), after the CP is transmitted before the subfields A1 and A2 representing the data of the HE-SIG-A field and the repetition subfields RA1 and RA2 The same CP can be transmitted. In a specific embodiment, the duration of the CP may be 0.8us. When a CP used for normal HE-SIG-A field transmission is applied after the sub-field indicating the data of the HE-SIG-A field and after the repetition sub-field in which the sub-field is repeated, The phase shift can be minimized during the conversion from the subfields to the repetitive subfields. In addition, it is possible to increase the probability that the wireless communication terminal receiving the physical layer frame receives the HE-SIG-A field.

The wireless communication terminal can apply a CP having a duration greater than the duration of the CP used for the general HE-SIG-A field transmission before the subfield indicating the data of the HE-SIG-A field. Specifically, as shown in Fig. 15C, CPs can be transmitted before the subfields A1 and A2 representing the data of the HE-SIG-A field. In a specific embodiment, the duration of the CP may be 1.6us. When a CP having a duration greater than a duration of a CP used for a general HE-SIG-A field transmission is applied before a subfield indicating data of an HE-SIG-A field, The phase shift can be minimized. In addition, the long CP duration can appropriately cancel the delay dispersion, and it is possible to increase the probability that the wireless communication terminal receiving the physical layer frame receives the HE-SIG-A field.

16 shows the operation of the wireless communication terminal according to the embodiment of the present invention.

16 illustrates operations of the first wireless communication terminal 1601 and the second wireless communication terminal 1603 according to the embodiment of the present invention.

The first wireless communication terminal 1601 sets a signaling field (S1601). The first wireless communication terminal 1601 may set the legacy signaling field as in the embodiment of Figs. Specifically, when transmitting the legacy signaling field, the first radio communication terminal 1601 transmits a predetermined first signal through at least one subcarrier among a plurality of subcarriers corresponding to the guard carrier position of the legacy training signal . In a specific embodiment, the first radio communication terminal 1601 includes a plurality of subcarriers for transmitting data of a legacy signaling field and a pilot signal among a plurality of subcarriers corresponding to positions of guard carriers of a legacy training signal, It is possible to transmit the first signal through one subcarrier. The first radio communication terminal 1601 is configured to transmit, to the first radio communication terminal 1601, two subcarriers having the highest frequency among the plurality of subcarriers corresponding to the position of the left guard carrier of the legacy training signal with reference to 0 in the frequency band, The first signal can be transmitted through the two subcarriers having the lowest frequency among the subcarriers having the lowest frequency. At this time, the legacy signaling field may be the L-SIG field described above.

After transmitting the legacy signaling field, the first wireless communication terminal 1601 may transmit the repeated legacy signaling field generated based on the legacy signaling field. At this time, the second wireless communication terminal 1603 can determine the physical layer frame received based on the repetitive legacy signaling field as a non-legacy physical layer frame.

When transmitting the repeated legacy signaling field, the first wireless communication terminal 1601 may transmit a predetermined second signal through at least one subcarrier among a plurality of subcarriers corresponding to the guard carrier position of the legacy training signal . The first wireless communication terminal 1601 may repeat the legacy signaling field to generate the repeated legacy signaling field. Also, the first wireless communication terminal 1601 may signal information other than the legacy signaling field through a combination of the first signal and the second signal. At this time, information other than the legacy signaling field may correspond to the embodiment described with reference to FIG.

The legacy signaling field includes length information indicating the duration of the non-legacy physical layer frame after the legacy signaling field. At this time, the length information may be the L_LENGTH field described above. The first wireless communication terminal 1601 transmits information other than the information indicating the duration of the non-legacy physical layer frame through the remaining value obtained by dividing the length information by the data size that can be transmitted by one OFDM symbol transmitting the legacy physical layer frame Signaling. Information other than the information indicating the duration of the non-legacy physical layer frame indicates whether the non-legacy physical layer frame includes the first signaling field, and the first signaling field indicates that the wireless communication terminal transmits data to the plurality of wireless communication terminals , Information on a plurality of wireless communication terminals can be signaled. In addition, information other than the information indicating the duration of the non-legacy physical layer frame indicates whether the second signaling field included in the non-legacy physical layer frame includes a field repeated in the time domain, and the second signaling field indicates either It can be commonly used when transmitting data to a wireless communication terminal and when transmitting data to a plurality of wireless communication terminals. At this time, the second signaling field may be the HE-SIG-A field described above. Also, the first signaling field may be the HE-SIG-B field described above.

In a specific embodiment, the first wireless communication terminal 1601 may transmit the remaining information obtained by dividing the length information by the data size that can be transmitted by one OFDM symbol transmitting the legacy physical layer frame, and a second OFDM symbol It is possible to signal information other than the information indicating the duration of the non-legacy physical layer frame through the modulation method of FIG. Specifically, the modulation method may be binary phase shift keying (BPSK) or quadrature binary phase shift keying (QBPSK).

Also, the first wireless communication terminal 1601 may transmit a second signaling field including a repeated field in the time domain. Specifically, the first wireless communication terminal 1601 may transmit a second signaling field including a repeated field in a time domain for long-distance data transmission. At this time, the structure of the second signaling field may be the same as the embodiment described with reference to FIG.

Also, the first wireless communication terminal 1601 can transmit the first signaling field when transmitting data to a plurality of wireless communication terminals. The first signaling field includes common information common to a plurality of wireless communication terminals and user specific information related to any one of the plurality of wireless communication terminals. At this time, the user characteristic information includes information on resource unit allocation, a sub-band index indicating a sub-frequency band, a resource unit size, and an MCS for transmitting data. And information on the number of space time streams (NSTS) used to transmit the data. The structure of the concrete first signaling field may be the same as the embodiment described with reference to FIG. 10 to FIG.

The first wireless communication terminal 1601 transmits a physical layer frame including a signaling field to the second wireless communication terminal 1603 (S1603). At this time, the first wireless communication terminal 1601 can transmit data to the second wireless communication terminal 1603 through a discontinuous frequency band. Specifically, the first wireless communication terminal 1601 can transmit data to the second wireless communication terminal 1603 through a discontinuous frequency band as in the embodiment of FIG.

The second wireless communication terminal 1603 receives the physical layer frame based on the signaling field (S1605). Specifically, the second wireless communication terminal 1603 receives a legacy training signal for reception setting of a legacy signaling field, and receives a legacy signaling field including information that the legacy wireless communication terminal can decode based on the legacy training signal do. At this time, the second radio communication terminal 1603 receives the first signal designated in advance through at least any one of the plurality of subcarriers corresponding to the position of the guard carrier of the legacy training signal, and based on the first signal Non-legacy signaling field. Specifically, when receiving the legacy signaling field, the second wireless communication terminal 1603 transmits a plurality of subcarriers for transmitting the data of the legacy signaling field and the pilot signal among the plurality of subcarriers corresponding to the position of the guard carrier of the legacy training signal And may receive the first signal through at least one of the consecutive subcarriers. When receiving the legacy signaling field, the second radio communication terminal 1603 selects, from the plurality of subcarriers corresponding to the position of the left guard carrier of the legacy training signal with respect to 0 in the frequency band, The first signal can be received through two subcarriers having the lowest frequency among the plurality of subcarriers corresponding to the positions of the guard carriers.

In addition, after receiving the legacy signaling field, the second wireless communication terminal 1603 receives the repeated legacy signaling field generated based on the legacy signaling field. At this time, the second wireless communication terminal 1603 can determine whether the physical layer frame received based on the repeated legacy signaling field is a non-legacy physical layer frame, as described above. When receiving the repeated legacy signaling field, the second wireless communication terminal 1603 receives a predetermined second signal through at least one subcarrier among a plurality of subcarriers corresponding to the guard carrier position of the legacy training signal .

The second wireless communication terminal 1603 transmits information other than the information indicating the duration of the non-legacy physical layer frame through the remaining value obtained by dividing the length information by the data size that can be transmitted by one OFDM symbol transmitting the legacy physical layer frame Can be obtained. Information other than the information indicating the duration of the non-legacy physical layer frame may be information according to the above-described embodiment. Also, the second wireless communication terminal 1603 may transmit the remaining information obtained by dividing the length information by the data size that can be transmitted by one OFDM symbol transmitting the legacy physical layer frame, and the modulation method of the second OFDM symbol transmitting the second signaling field Information other than the information indicating the duration of the non-legacy physical layer frame can be obtained. Specifically, the modulation method may be binary phase shift keying (BPSK) or quadrature binary phase shift keying (QBPSK).

While the present invention has been described by taking the wireless LAN communication as an example, the present invention is not limited thereto and can be applied to other communication systems such as cellular communication. Also, while the method, apparatus, and system of the present invention have been described in connection with specific embodiments thereof, some or all of the elements, acts or operations of the present invention may be implemented using a computer system having a general purpose hardware architecture.

The features, structures, effects and the like described in the embodiments are included in at least one embodiment of the present invention and are not necessarily limited to one embodiment. Further, the features, structures, effects, and the like illustrated in the embodiments can be combined and modified by other persons having ordinary skill in the art to which the embodiments belong. Therefore, it should be understood that the present invention is not limited to these combinations and modifications.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (20)

In a wireless communication terminal that wirelessly communicates,
A transmission / reception unit; And
A processor,
The processor
A legacy signaling field including information decodable by the legacy wireless communication terminal through the transceiver and a legacy training signal for setting reception of the legacy signaling field,
When transmitting the legacy signaling field, transmitting a first predetermined signal through at least one subcarrier among a plurality of subcarriers corresponding to a guard carrier position of the legacy training signal
Wireless communication terminal. The method of claim 1,
The processor
A plurality of subcarriers for transmitting the data of the legacy signaling field and a pilot signal among a plurality of subcarriers corresponding to positions of guard carriers of the legacy training signal when transmitting the legacy signaling field, Lt; RTI ID = 0.0 >
Wireless communication terminal. 3. The method of claim 2,
The processor
Wherein when transmitting the legacy signaling field, two subcarriers having the highest frequency among the plurality of subcarriers corresponding to the position of the left guard carrier of the legacy training signal with reference to 0 in the frequency band, and a plurality of subcarriers corresponding to the positions of the right guard carriers The first signal is transmitted through two subcarriers having the lowest frequency among the subcarriers of
Wireless communication terminal. The method of claim 1,
The processor
After transmitting the legacy signaling field, transmitting an iterative signaling field generated based on the legacy signaling field,
When transmitting the repetitive legacy signaling field, transmitting a second predetermined signal through at least one subcarrier among a plurality of subcarriers corresponding to a guard carrier position of the legacy training signal
Wireless communication terminal. 5. The method of claim 4,
The processor
Repeating the legacy signaling field to generate the repeating legacy signaling field
Wireless communication terminal. 5. The method of claim 4,
The processor
Signaling information other than the legacy signaling field through a combination of the first signal and the second signal
Wireless communication terminal. 5. The method of claim 4,
Wherein the first signal and the second signal are identical
Wireless communication terminal. The method of claim 1,
Wherein the legacy signaling field includes length information indicating a duration of a non-legacy physical layer frame after a legacy signaling field,
The processor
Signaling information other than the information indicating the duration of the non-legacy physical layer frame through the remaining value obtained by dividing the length information by the data size that can be transmitted by one OFDM symbol transmitting the legacy physical layer frame
Wireless communication terminal. 9. The method of claim 8,
The processor
Information other than the information indicating the duration of the non-legacy physical layer frame indicates whether the non-legacy physical layer frame includes a first signaling field,
The first signaling field may include a signaling information for a plurality of wireless communication terminals when the wireless communication terminal transmits data to a plurality of wireless communication terminals
Wireless communication terminal. The method of claim 9,
Information other than the information indicating the duration of the non-legacy physical layer frame indicates whether the second signaling field included in the non-legacy physical layer frame includes a field repeated in the time domain,
The second signaling field is commonly used when transmitting data to one of the wireless communication terminals and when transmitting data to a plurality of wireless communication terminals
Wireless communication terminal. 11. The method of claim 10,
The processor
And transmitting the second signaling field to the non-legacy physical layer through a remaining value obtained by dividing the length information by a data size that can be transmitted by one OFDM symbol transmitting a legacy physical layer frame and a second OFDM symbol transmitting the second signaling field. Signaling information other than the information indicating the duration of the frame
Wireless communication terminal. 12. The method of claim 11,
The modulation method may be binary phase shift keying (BPSK) or quadrature binary phase shift keying (QBPSK)
Wireless communication terminal. In a wireless communication terminal that wirelessly communicates,
A transmission / reception unit; And
A processor,
The processor
Receiving a legacy training signal for reception setting of a legacy signaling field through the transceiver, receiving a legacy signaling field including information that the legacy wireless communication terminal can decode based on the legacy training signal,
Receiving a predetermined first signal through at least any one of a plurality of subcarriers corresponding to a guard carrier position of the legacy training signal,
Receiving a non-legacy signaling field for signaling information for a non-legacy wireless communication terminal based on the first signal;
Wireless communication terminal. The method of claim 13,
The processor
A plurality of subcarriers for transmitting data and a pilot signal of the legacy signaling field among a plurality of subcarriers corresponding to guard carrier positions of the legacy training signal when receiving the legacy signaling field, Receiving the first signal over a carrier
Wireless communication terminal. The method of claim 14,
The processor
When receiving the legacy signaling field, the subcarriers corresponding to the positions of two subcarriers having the highest frequency among the plurality of subcarriers corresponding to the position of the left guard carrier of the legacy training signal with reference to 0 in the frequency band, The first signal is received through two subcarriers having the lowest frequency among the plurality of subcarriers
Wireless communication terminal. The method of claim 13,
The processor
Receiving an iterative signaling field generated based on the legacy signaling field through the transceiver after receiving the legacy signaling field,
Receiving a second predetermined signal through at least one subcarrier among a plurality of subcarriers corresponding to a guard carrier position of the legacy training signal when receiving the repeated legacy signaling field;
Wireless communication terminal. 17. The method of claim 16,
Wherein the first signal and the second signal are identical
Wireless communication terminal. The method of claim 13,
Wherein the legacy signaling field includes length information indicating a duration of a non-legacy physical layer frame after a legacy signaling field,
The processor
Information other than the information indicating the duration of the non-legacy physical layer frame is acquired through a residual value obtained by dividing the length information by a data size that can be transmitted by one OFDM symbol transmitting the legacy physical layer frame
Wireless communication terminal. The method of claim 18,
The processor
Information other than the information indicating the duration of the non-legacy physical layer frame indicates whether the non-legacy physical layer frame includes a first signaling field,
The first signaling field may include a signaling information for a plurality of wireless communication terminals when the wireless communication terminal transmits data to a plurality of wireless communication terminals
Wireless communication terminal. In an operation method of a wireless communication terminal that wirelessly communicates,
Transmitting a legacy training signal for reception setting of a legacy signaling field including information decodable by a legacy wireless communication terminal; And
Transmitting a legacy signaling field,
The step of transmitting the legacy signaling field
And transmitting a predetermined first signal through at least one subcarrier among a plurality of subcarriers corresponding to a position of a guard carrier of the legacy training signal
Wireless communication terminal.

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