阅读说明：本技术 通信设备、信息处理设备、通信方法以及程序 (Communication device, information processing device, communication method, and program ) 是由 猪膝裕彦 于 2020-02-05 设计创作，主要内容包括：该通信设备发送无线电帧,该无线电帧具有物理(PHY)层的前导码和数据字段。前导码包括L-STF、L-LTF、L-SIG、EHT-SIG-A、EHT-STF以及EHT-LTF,EHT-SIG-A包括表示调制方案和编码率(MCS,调制和编码方案)的信息的子字段,数据字段包括根据子字段表示的调制方案和编码率进行调制和编码的数据,并且子字段被构造为使得指定2048QAM和4096QAM中的至少一个作为调制方案。(The communication device transmits a radio frame having a preamble and a data field of a Physical (PHY) layer. The preamble includes L-STF, L-LTF, L-SIG, EHT-SIG-A, EHT-STF, and EHT-LTF, the EHT-SIG-a includes sub-fields indicating information of a modulation scheme and a coding rate (MCS, modulation and coding scheme), the data field includes data modulated and coded according to the modulation scheme and coding rate indicated by the sub-fields, and the sub-fields are configured such that at least one of 2048QAM and 4096QAM is designated as the modulation scheme.)

1. A communication device, comprising a transmitting section for transmitting a radio frame including a preamble and a data field of a Physical (PHY) layer,

wherein the preamble includes a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal field (L-SIG), a very high throughput signal A field (EHT-SIG-A), an EHT short training field (EHT-STF), and an EHT long training field (EHT-LTF),

the EHT-SIG-A includes subfields that indicate information of a modulation scheme and a coding rate (MCS, modulation and coding scheme),

the data field includes data modulated and encoded according to the modulation scheme and the coding rate indicated by the subfield, and

the subfield is constructed to be able to designate at least one of 2048QAM and 4096QAM as a modulation scheme.

2. A communication device, comprising a transmitting section for transmitting a radio frame including a preamble and a data field of a Physical (PHY) layer,

wherein the preamble includes a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal field (L-SIG), a very high throughput signal A field (EHT-SIG-A), a very high throughput signal B field (EHT-SIG-B), an EHT short training field (EHT-STF), and an EHT long training field (EHT-LTF),

the EHT-SIG-B includes subfields that indicate information of a modulation scheme and a coding rate (MCS, modulation and coding scheme),

the data field includes data modulated and encoded according to the modulation scheme and the coding rate indicated by the subfield, and

the subfield is constructed to be able to designate at least one of 2048QAM and 4096QAM as a modulation scheme.

3. A communication device, comprising a receiving section for receiving a radio frame including a preamble and a data field of a Physical (PHY) layer,

wherein the preamble includes a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal field (L-SIG), a very high throughput signal A field (EHT-SIG-A), an EHT short training field (EHT-STF), and an EHT long training field (EHT-LTF),

the EHT-SIG-A includes subfields that indicate information of a modulation scheme and a coding rate (MCS, modulation and coding scheme),

the data field includes data modulated and encoded according to the modulation scheme and the coding rate indicated by the subfield, and

the subfield is constructed to be able to designate at least one of 2048QAM and 4096QAM as a modulation scheme.

4. A communication device comprising a receiver for receiving a radio frame comprising a preamble and a data field of a Physical (PHY) layer,

wherein the preamble includes a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal field (L-SIG), a very high throughput signal A field (EHT-SIG-A), a very high throughput signal B field (EHT-SIG-B), an EHT short training field (EHT-STF), and an EHT long training field (EHT-LTF),

the EHT-SIG-B includes subfields that indicate information of a modulation scheme and a coding rate (MCS, modulation and coding scheme),

the data field includes data modulated and encoded according to the modulation scheme and the coding rate indicated by the subfield, and

the subfield is constructed to be able to designate at least one of 2048QAM and 4096QAM as a modulation scheme.

5. The communication device of any of claims 1-4, wherein the subfield consists of no less than five bits.

6. An information processing apparatus characterized by comprising a generation section for generating a radio frame including a preamble and a data field of a Physical (PHY) layer,

wherein the preamble includes a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal field (L-SIG), a very high throughput signal A field (EHT-SIG-A), an EHT short training field (EHT-STF), and an EHT long training field (EHT-LTF),

the EHT-SIG-A includes subfields that indicate information of a modulation scheme and a coding rate (MCS, modulation and coding scheme),

the data field includes data modulated and encoded according to the modulation scheme and the coding rate indicated by the subfield, and

the subfield is constructed to be able to designate at least one of 2048QAM and 4096QAM as a modulation scheme.

7. An information processing apparatus characterized by comprising a generation section for generating a radio frame including a preamble and a data field of a Physical (PHY) layer,

wherein the preamble includes a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal field (L-SIG), a very high throughput signal A field (EHT-SIG-A), a very high throughput signal B field (EHT-SIG-B), an EHT short training field (EHT-STF), and an EHT long training field (EHT-LTF),

the EHT-SIG-B includes subfields that indicate information of a modulation scheme and a coding rate (MCS, modulation and coding scheme),

the data field includes data modulated and encoded according to the modulation scheme and the coding rate indicated by the subfield, and

the subfield is constructed to be able to designate at least one of 2048QAM and 4096QAM as a modulation scheme.

8. A communication method for transmitting a radio frame, the radio frame including a preamble and a data field of a Physical (PHY) layer, characterized by:

the preamble includes a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal field (L-SIG), a very high throughput signal A field (EHT-SIG-A), an EHT short training field (EHT-STF), and an EHT long training field (EHT-LTF),

the EHT-SIG-A includes subfields that indicate information of a modulation scheme and a coding rate (MCS, modulation and coding scheme),

the data field includes data modulated and encoded according to the modulation scheme and the coding rate indicated by the subfield, and

the subfield is constructed to be able to designate at least one of 2048QAM and 4096QAM as a modulation scheme.

9. A communication method for transmitting a radio frame, the radio frame including a preamble and a data field of a Physical (PHY) layer, characterized by:

the preamble includes a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal field (L-SIG), a very high throughput signal A field (EHT-SIG-A), a very high throughput signal B field (EHT-SIG-B), an EHT short training field (EHT-STF), and an EHT long training field (EHT-LTF),

the EHT-SIG-B includes subfields that indicate information of a modulation scheme and a coding rate (MCS, modulation and coding scheme),

the data field includes data modulated and encoded according to the modulation scheme and the coding rate indicated by the subfield, and

the subfield is constructed to be able to designate at least one of 2048QAM and 4096QAM as a modulation scheme.

10. A communication method for receiving a received radio frame, the radio frame comprising a preamble and a data field of a Physical (PHY) layer, characterized by:

the preamble includes a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal field (L-SIG), a very high throughput signal A field (EHT-SIG-A), an EHT short training field (EHT-STF), and an EHT long training field (EHT-LTF),

the EHT-SIG-A includes subfields that indicate information of a modulation scheme and a coding rate (MCS, modulation and coding scheme),

the data field includes data modulated and encoded according to the modulation scheme and the coding rate indicated by the subfield, and

the subfield is constructed to be able to designate at least one of 2048QAM and 4096QAM as a modulation scheme.

11. A communication method for receiving a radio frame, the radio frame comprising a preamble and a data field of a Physical (PHY) layer, characterized by:

the preamble includes a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal field (L-SIG), a very high throughput signal A field (EHT-SIG-A), a very high throughput signal B field (EHT-SIG-B), an EHT short training field (EHT-STF), and an EHT long training field (EHT-LTF),

the EHT-SIG-B includes subfields that indicate information of a modulation scheme and a coding rate (MCS, modulation and coding scheme),

the data field includes data modulated and encoded according to the modulation scheme and the coding rate indicated by the subfield, and

the subfield is constructed to be able to designate at least one of 2048QAM and 4096QAM as a modulation scheme.

12. The communication method according to any one of claims 8 to 11, wherein the subfield is composed of not less than five bits.

13. A program configured to cause a computer to function as one of the communication apparatus defined in any one of claims 1 to 5 and the information processing apparatus defined in claim 6 or 7.

Technical Field

The present invention relates to a communication control technique in a wireless LAN.

Background

In recent years, with the development of information communication technology, the usage of the internet has increased year by year, and various communication technologies have been developed to cope with the increase in demand. In particular, wireless local area network (wireless LAN) technology has achieved an increase in the throughput of packet data, audio, video, and the like by wireless LAN terminals in internet communication, and various technological developments are still actively underway.

In the development of wireless LAN technology, a lot of standardization work of IEEE (Institute of Electrical and Electronics Engineers) 802 has played an important role as a standardization organization of wireless LAN technology. As one of the wireless LAN communication standards, the IEEE802.11 standard is well known, and includes standards such as ieee802.11n/a/b/g/ac and ieee802.11ax. For example, ieee802.11ax realizes high peak throughput up to 9.6 gigabits/second (Gbps), and also improves communication speed in a congestion situation with OFDMA (orthogonal frequency division multiple access) (PTL 1).

In recent years, in order to further improve throughput, a research group called IEEE802.11EHT (extremely high throughput) has been established as a subsequent standard of ieee802.11ax. As one of measures of throughput improvement targeted at IEEE802.11EHT, introduction of 2048QAM or 4096QAM, which is a multi-value modulation scheme, has been examined. Note that QAM is an abbreviation of Quadrature Amplitude Modulation. According to this multi-value modulation scheme, one symbol can transmit a plurality of bits (11 bits/symbol in 2048QAM and 12 bits/symbol in 4096 QAM), and further improvement in throughput can be achieved.

Reference list

Patent document

PTL 1: japanese patent laid-open No. 2018-50133

Disclosure of Invention

Technical problem

As described above, in IEEE802.11EHT, data transmission using 2048QAM or 4096QAM modulation schemes has been examined. However, in the conventional standards of the wireless LAN, a mechanism configured to notify that 2048QAM or 4096QAM is used as a modulation scheme of data to be transmitted has not been defined.

In view of the above, the present invention provides a mechanism configured to notify that 2048QAM or 4096QAM is used as a modulation scheme of data to be transmitted.

Means for solving the problems

A communication apparatus according to an aspect of the present invention has the following features. That is, there is provided a communication device including a transmitting section for transmitting a radio frame including a preamble of a Physical (PHY) layer and a data Field, wherein the preamble includes L-STF (Legacy Short Training Field), "Legacy Short Training Field"), L-LTF (Legacy Long Training Field), "Legacy Long Training Field"), L-SIG (Legacy Signal Field, "Legacy Signal Field"), EHT-SIG-a (very High Throughput Signal a Field, "outgoing High Signal a Field"), EHT-f (EHT Short Training Field, "EHT Short Training Field"), and EHT-LTF (EHT Long Training Field, "EHT Long Training Field"). The EHT-SIG-a includes a subfield of information (MCS, Modulation and Coding Scheme) indicating a Modulation Scheme and a Coding rate, the data field includes data modulated and coded according to the Modulation Scheme and the Coding rate indicated by the subfield, and the subfield is configured to be able to designate at least one of 2048QAM and 4096QAM as a Modulation Scheme.

The invention has the advantages of

According to the present invention, it is possible to notify that data transmission using a 2048QAM or 4096QAM modulation scheme is performed.

Other features and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings. Note that the same reference numerals are used throughout the drawings to designate the same or similar components.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.

Fig. 1 is a view showing an example of the configuration of a network;

fig. 2 is a block diagram showing an example of a functional configuration of an AP;

fig. 3 is a block diagram showing an example of a hardware configuration of an AP;

fig. 4 is a flowchart showing a process performed by the AP;

fig. 5 is a sequence diagram showing a process performed in the wireless communication network;

fig. 6 is a view showing an example of a PHY frame structure of an EHT SU PPDU;

fig. 7 is a view showing an example of a PHY frame structure of an EHT ER PPDU; and

fig. 8 is a view showing an example of a PHY frame structure of an EHT MU PPDU.

Detailed Description

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following examples are not intended to limit the scope of the claimed invention. A plurality of features are described in the embodiments, but not limiting the invention to all such features, a plurality of such features may be combined as appropriate. Further, in the drawings, the same reference numerals are given to the same or similar configurations, and redundant description thereof is omitted.

(network construction)

Fig. 1 shows an example of the configuration of a wireless communication network according to the present embodiment. The wireless communication network is configured to include three STAs (STA 103, STA 104, and STA 105) and one access point (AP 102) as devices (EHT devices) conforming to IEEE802.11EHT (extremely high throughput) standard. Note that the name "IEEE802.11EHT" is provided for convenience and may be other names at the time of standard establishment, but this specification and the appended claims are intended to cover all standards capable of supporting the processing described later. The AP 102 may be considered as a form of STA because it has the same functions as the STAs 103 to 105 in addition to the relay function. STAs within circle 101 may communicate with AP 102, and circle 101 represents the area where signals transmitted by AP 102 arrive. The AP 102 communicates with the STAs 103 to 105 according to the wireless communication method of the IEEE802.11EHT standard. The AP 102 may establish a radio link with each of the STAs 103 to 105 via a connection process (e.g., association process) compliant with the IEEE802.11 series of standards.

Note that the configuration of the wireless communication network shown in fig. 1 is merely an example for description, and for example, a network including a plurality of EHT devices and legacy devices (communication devices conforming to the ieee802.11a/b/g/n/ax standard) may be formed in a wider area. In addition, the arrangement of the communication devices is not limited to that shown in fig. 1, and the following discussion is also applicable to various positional relationships of various types of communication devices.

(construction of AP)

Fig. 2 is a block diagram showing a functional configuration of the AP 102. As an example of its functional configuration, the AP 102 includes a wireless LAN control unit 201, a frame generation unit 202, a signal analysis unit 203, and a UI (user interface) control unit 204.

The wireless LAN control unit 201 may be configured to include one or more antennas 205 and circuits configured to transmit and receive radio signals (radio frames) to and from other wireless LAN devices, and a program configured to control them. The wireless LAN control unit 201 performs communication control of the wireless LAN based on the frame generated by the frame generation unit 202 according to the IEEE802.11 series standard.

The frame generation unit 202 generates a frame to be transmitted by the wireless LAN control unit 201 according to the analysis result of the signal received by the wireless LAN control unit 201 by the signal analysis unit 203. The frame generation unit 202 may create a frame independently of the analysis result of the signal analysis unit 203. The signal analysis unit 203 analyzes the signal received by the wireless LAN control unit 201. The UI control unit 204 accepts an operation by a user (not shown) of the AP 102 on the input unit 304 (fig. 3), and performs control of transmitting a control signal corresponding to the operation to each constituent element, or control of output (including display and the like) of the output unit 305 (fig. 3).

Fig. 3 shows a hardware configuration of the AP 102 according to the present embodiment. As an example of its hardware configuration, the AP 102 includes a storage unit 301, a control unit 302, a function unit 303, an input unit 304, an output unit 305, a communication unit 306, and one or more antennas 205.

The storage unit 301 is constituted by one or both of a ROM and a RAM, and stores programs for performing various operations described later and various information such as communication parameters for wireless communication. Note that a storage medium such as a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a nonvolatile memory card, or a DVD may be used as the storage unit 301 in addition to the memory such as the ROM and the RAM.

The control unit 302 is configured of, for example, one or more processors such as a CPU and an MPU, an ASIC (application specific integrated circuit), a DSP (digital signal processor), an FPGA (field programmable gate array), or the like. Here, the CPU is an acronym of a central processing unit, and the MPU is an acronym of a microprocessing unit. The control unit 302 executes the program stored in the storage unit 301, thereby controlling the entire AP 102. Note that the control unit 302 can control the entire AP 102 by cooperation of the program stored in the storage unit 301 and an OS (operating system).

Further, the control unit 302 controls the functional unit 303 to execute predetermined processing such as image capturing, printing, or projection. The functional unit 303 is hardware for the AP 102 to execute predetermined processing. For example, if the AP 102 is a camera, the function unit 303 is an image capturing unit, and performs image capturing processing. For example, if the AP 102 is a printer, the functional unit 303 is a printing unit and performs print processing. For example, if the AP 102 is a projector, the function unit 303 is a projection unit and performs projection processing. The data to be processed by the function unit 303 may be data stored in the storage unit 301, or may be data communicated with a STA or other AP via a communication unit 306 described later.

The input unit 304 accepts various operations from the user. The output unit 305 performs various types of output for the user. Here, the output of the output unit 305 includes at least one of display on a screen, audio output of a speaker, vibration output, and the like. Note that both the input unit 304 and the output unit 305 can be implemented by one module, for example, a touch panel.

The communication unit 206 controls wireless communication conforming to IEEE802.11EHT standard, or wireless communication conforming to Wi-Fi or IP (internet protocol) communication (including modulation and coding processing). In addition, the communication unit 306 controls one or more antennas 205 to transmit/receive radio signals for wireless communication. In this case, MIMO (multiple input multiple output) communication using spatial streams is possible. The communication unit 306 is a so-called radio chip, which may itself comprise one or more processors and memory. The AP 102 communicates contents such as image data, file data, and video data with other communication devices through the communication unit 306. Note that the functions of the constituent elements shown in fig. 2 may be partially implemented by software.

(STA configuration)

The functional configuration and hardware configuration of the STAs 103 to 105 are the same as those of the AP 102 described above (fig. 2) and (fig. 3), respectively. That is, each of the STAs 103 to 105 may be configured to include the wireless LAN control unit 201, the frame generation unit 202, the signal analysis unit 203, and the UI control unit 204 as its functional configuration, and include the storage unit 301, the control unit 302, the function unit 303, the input unit 304, the output unit 305, the communication unit 306, and one or more antennas 205 as its hardware configuration.

(treatment Process)

Next, a procedure of processing performed by the AP 102 configured as described above and a sequence of processing performed by the wireless communication system shown in fig. 1 will be described with reference to fig. 4 and 5. Fig. 4 is a flowchart showing the processing performed by the AP 102. The flowchart shown in fig. 4 can be implemented when the control unit 302 of the AP 102 executes a control program stored in the storage unit 301 and performs calculation and processing of information and control of each hardware. Fig. 5 shows a sequence diagram of a process performed by the wireless communication system.

The AP 102 performs connection processing conforming to the IEEE802.11 series standard for each of the STAs 103 to 105 (steps S401, F501). That is, frames such as a probe request/response, an association request/response, and Auth (authentication) are transmitted/received between the AP 102 and each of the STA 104 and the STA105, thereby establishing a radio link. Next, the AP 102 decides a modulation scheme and a code rate to be used for wireless communication as a value (level) of MCS (modulation and coding scheme). The MCS shows a combination of a modulation scheme and a coding rate as an index (index). The MCS value used in the present embodiment and the relationship between the modulation scheme and the coding rate corresponding to the value of the MCS will be described later with reference to table 3. The value of MCS may be decided by the signal analysis unit 203 according to the reception state in the AP 102. For example, the MCS value may be determined according to the quality and Strength of signals Received from the STAs (SNR (Signal to Noise Ratio), SINR (Signal-to-Interference Noise Ratio), RSSI (Received Signal Strength Indicator), RSSQ (Received Signal Strength quality), and the like. Further, the value of the MCS may be predetermined in the wireless communication system. The value of the MCS may be determined by a user (not shown) of AP 102 operating on input unit 304. As described above, the method of determining the value of the MCS is not limited to the specified method.

Next, the AP 102 decides communication parameters including the value of the MCS decided in step S402 or F502, which are included in the radio frame to be transmitted (steps S403, F503). Next, the AP 102 transmits data to the STAs 103 to 105 in the form of a radio frame including the decided transmission data communication parameters and data (steps S404, F504).

(frame Structure)

Fig. 6 to 8 show examples of a PHY (physical layer) frame structure of a PPDU defined by the IEEE802.11EHT standard and transmitted in step S404 or F504. Note that PPDU is an abbreviation for physical layer (PHY) protocol data unit. Fig. 6 shows an example of a PHY frame structure of an EHT SU PPDU, which is a PPDU for Single User (SU) communication (between an AP and a single STA). Fig. 7 shows an example of a PHY frame structure of an EHT ER PPDU as a PPDU for communication in an extended area (communication distance) (extended range). The EHT ER PPDU is used for communication between the AP and a single STA. Fig. 8 shows an example of a PHY frame structure of an EHT MU PPDU, which is a PPDU for multi-user (MU) communication (between an AP and a plurality of STAs).

The information generally included in the PPDUs shown in fig. 6 to 8 is an STF (short training field), an LTF (long term field), and a SIG (signal field). Taking FIG. 6 as an example, the PPDU header includes L (legacy) -STF 601, L-LTF 602, and L-SIG 603 with backward compatibility with the IEEE802.11a/b/g/n/ax standard. The L-STF 601 is used for detection of PHY frame signals, Automatic Gain Control (AGC), timing detection, and the like. The L-LTF 602 arranged immediately after the L-STF 601 is used for high-precision frequency/time synchronization, acquisition of propagation channel information (CSI), and the like. The L-SIG 603 arranged immediately after the L-LTF 602 is used to transmit control information including information such as a data transmission rate and a PHY frame length. Legacy devices conforming to the IEEE802.11a/b/g/n/ax standard can decode data of the various legacy fields described above (L-STF 601, L-LTF 602, and L-SIG 603). Various types of legacy fields are also included in the PPDU shown in fig. 7 and 8.

Beside the L-STF 601, L-LTF 602, and L-SIG 603 described above, the EHT SU PPDU shown in FIG. 6 includes RL-SIG 604, EHT-SIG-A605, EHT-STF 606, EHT-LTF 607, data field 608, and packet extension 609. The RL-SIG 604 may not be present. The EHT-SIG-A605 is disposed immediately after the L-SIG 603, the EHT-STF 606 is disposed immediately after the EHT-SIG-A605, and the EHT-LTF 607 is disposed immediately after the EHT-STF 606. Note that fields including L-STF 601, L-LTF 602, L-SIG 603, RL-SIG 604, EHT-SIG-a 605, EHT-STF 606, and EHT-LTF 607 are referred to as preambles. EHT-SIG-A605 includes information required to receive the PPDU, such as EHT-SIG-A1 and EHT-SIG-A2. The sub-fields constituting the EHT-SIG-A1 and EHT-SIG-A2 included in the EHT-SIG-A605 and descriptions thereof are shown in tables 1 and 2.

[ Table 1]

[ Table 2]

The MCS decided in step S402 or F502 is shown by 5 bits of the MCS subfield (B3-B7) in EHT-SIG-A1 (Table 1). Table 3 shows a corresponding example between the MCS value shown in the MCS subfield and the modulation scheme and coding rate corresponding to the MCS value. In table 3, the values of MCS are from 0 to 17, and modulation schemes and coding rates are set corresponding to the respective values of MCS. In addition, as shown in table 3, the MCS subfield is constructed to designate at least one of 2048QAM and 4096QAM as a modulation scheme. The MCS values corresponding to the 2048QAM modulation scheme are 12 to 14, and the MCS values corresponding to the 4096QAM modulation scheme are 15 to 17. Even in the same modulation scheme, if the value of the MCS changes, the coding rate to be used also changes. For example, if the value of the MCS is 15, the coding rate is 2/4. If the value of the MCS is 16, the coding rate is 3/4. If the value of MCS is 17, the coding rate is 5/6. Note that in table 3, three different coding rates are prepared corresponding to each of the 2048QAM and 4096QAM modulation schemes. However, the present invention is not limited thereto, and four or more different coding rates may be prepared. Although the 5-bit MCS subfield is prepared in the present embodiment, since more multivalued modulation schemes can be used in the subsequent standard of the IEEE802.11EHT standard, it is possible to ensure that the number of bits of the MCS subfield exceeds 5 bits, for example, 6 bits.

[ Table 3]

The EHT-STF 606 next to the EHT-SIG-A605 is an abbreviation for EHT short training field, whose main purpose is to improve automatic gain control in MIMO transmissions. EHT-LTF 607 is an abbreviation for EHT long training field and provides a means to estimate the MIMO channel to the receiver. The data field 608 includes data modulated and encoded using a modulation scheme and a coding rate corresponding to the value of the MCS represented by the MCS subfield of the EHT-SIG-a1 described above. The communication Apparatus (AP) on the transmitting side modulates and encodes the data in the data field 608, stores MCS information (value (level) of MCS) for modulation and encoding in the MCS subfield of the EHT-SIG-a1, and transmits PPDU to the communication apparatus (STA) on the receiving side. The communication device on the reception side may demodulate and decode the reception data in the data field according to MCS information contained in the MCS subfield of the EHT-SIG-a1 of the received PPDU.

As described above, the EHT ER PPDU shown in fig. 7 is a PPDU for extending a communication distance and is used for communication between an AP and a single STA. The EHT ER PPDU includes an L-STF 701, an L-LTF 702, an L-SIG 703, an RL-SIG 704, an EHT-SIG-A705, an EHT-STF 706, an EHT-LTF 707, a data field 708, and a packet extension 709. The RL-SIG 704 may not be present. L-LTF 702 is disposed immediately after L-STF 701, L-SIG 703 is disposed immediately after L-LTF 702, EHT-SIG-A705 is disposed immediately after L-SIG 703, EHT-STF 706 is disposed immediately after EHT-SIG-A705, and EHT-LTF 707 is disposed immediately after EHT-STF 706. Note that fields including L-STF 701, L-LTF 702, L-SIG 703, RL-SIG 704, EHT-SIG-A705, EHT-STF 706, and EHT-LTF 707 are referred to as preambles. The information contained in each field is the same as that in the EHT SU PPDU shown in fig. 6, and a description thereof will be omitted. Note that in EHT-SIG-A705, the value of MCS may be set in the MCS sub-field (B3-B7) of EHT-SIG-A1, as in the EHT SU PPDU shown in FIG. 6.

The EHT MU PPDU shown in fig. 8 is a PPDU used for communication of MUs, as described above. The EHT MU PPDU includes L-STF801, L-LTF 802, L-SIG 803, RL-SIG 804, EHT-SIG-A805, EHT-SIG-B806, EHT-STF 807, EHT-LTF 808, data field 809, and packet extension 810. The RL-SIG 804 may be absent. L-LTF 802 is disposed immediately after L-STF801, L-SIG 803 is disposed immediately after L-LTF 802, EHT-SIG-A805 is disposed immediately after L-SIG 803, EHT-SIG-B806 is disposed immediately after EHT-SIG-A805, EHT-STF 807 is disposed immediately after EHT-SIG-B806, and EHT-LTF 808 is disposed immediately after EHT-STF 807. Note that fields including L-STF801, L-LTF 802, L-SIG 803, RL-SIG 804, EHT-SIG-A805, EHT-SIG-B806, EHT-STF 807, and EHT-LTF 808 are referred to as preambles. In the data field 809, data of a plurality of STAs (users) is transmitted by MIMO or OFDMA (Orthogonal Frequency Division Multiple Access).

EHT-SIG-A805 includes information necessary to receive the PPDU, such as EHT-SIG-A1 and EHT-SIG-A2. The sub-fields constituting the EHT-SIG-A1 and EHT-SIG-A2 included in the EHT-SIG-A805 and descriptions thereof are shown in tables 4 and 5.

[ Table 4]

[ Table 5]

The EHT-SIG-B806 includes information required to receive the PPDU, such as a common field and a user block field. Subfields constituting the common field and the user block field included in the EHT-SIG-B806 and descriptions thereof are shown in tables 6 and 7.

[ Table 6]

[ Table 7]

The EHT-SIG-B806 includes a common field for information common to all STAs (users) and as many user block fields as communicating STAs. Also, the content of the user field in the user block field changes depending on whether the AP performs MIMO communication. Table 8 shows the description of the user field in the case of non-MIMO communication, and table 9 shows the description of the user field in the case of MU-MIMO communication.

[ Table 8]

[ Table 9]

In tables 8 and 9, the modulation scheme and coding rate (i.e., the value (level) of MCS) used for the modulation and coding process of data in the data field of each STA are indicated by 5-bit MCS subfields. An example of the correspondence between the value of the MCS shown in the MCS subfield and the modulation scheme and the coding rate corresponding to the value of the same MCS is the same as shown in table 3.

When the frame structures of the EHT SU PPDU, the EHT ER PPDU, and the EHT MU PPDU, which are PPDUs used in the IEEE802.11EHT standard according to the present embodiment, are used in the above-described manner, data transmission using 2048QAM or 4096QAM modulation schemes may be notified. Note that, in addition to the AP 102 and the STAs 103 to 105 as communication devices, an information processing device (e.g., a radio chip) for generating the above-described PHY preamble may also implement the present invention.

Note that fig. 6 shows that the ieee802.11a/b/g/n/ax standard has a backward compatible frame structure. The fields of the L-STF and L-LTG may be omitted if backward compatibility is not required to be ensured. Instead, EHT-STF and EHT-LTF may be inserted. Note that the respective fields of the respective PPDUs are not necessarily arranged in the order shown in each of fig. 6 to 8, or may include new fields not shown in each of fig. 6 to 8.

(other embodiments)

The present invention can be realized by the following processing: the program for implementing one or more functions of the above-described embodiments is supplied to a system or an apparatus via a network or a storage medium, and causes one or more processors in a computer of the system or the apparatus to read out and execute the program. The present invention may also implement one or more functions via a circuit (e.g., ASIC).

The present invention is not limited to the above-described embodiments, and various changes and modifications can be made within the spirit and scope of the present invention. Therefore, for the public to appreciate the scope of the present invention, the following claims are made.

This application claims priority from japanese patent application No. 2019-036406, filed on 28.2.2019, which is incorporated herein by reference.