Communication device, wireless reception device, and communication method

Abstract

A communication device according to the present invention comprises: a control circuit that generates a coverage extension signal so that a data part included in the coverage extension signal is robustly transmitted; and a transmission circuit that transmits the generated coverage extension signal. In the robust transmission, the data part may be transmitted using tones discretely arranged in a bandwidth.

Description

Communication device, wireless receiving device, and communication method

[0001] The present disclosure relates to a communication device, a wireless receiving device, and a communication method.

[0002] The Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, IEEE 802.11bn (hereinafter referred to as "11bn"), is being developed by a study group (SG) as a successor to IEEE 802.11be (hereinafter referred to as "11be"), which is also known as "Extremely High Throughput (EHT)." 11bn is also known as "Ultra High Reliability (UHR)."

[0003] IEEE 802.11-24 / 875r1, NXPIEEE 802.11-24 / 921r0, AppleIEEE 802.11-24 / 873r0, MediatekIEEE 802.11-24 / 460r1, Cisco SystemsIEEE 802.11-15 / 132r17, Spec Framework

[0004] Wireless communication standards such as wireless LAN require an extension of the coverage area where data can be correctly decoded between transmitter and receiver (also known as enhanced long range (ELR)). However, the appropriate transmission method for coverage extension signals has not been fully explored.

[0005] Non-limiting examples of the present disclosure contribute to providing a communication device, a wireless receiving device, and a communication method that can appropriately transmit and receive a coverage extension signal in wireless communication.

[0006] A communication device according to one embodiment of the present disclosure includes a control circuit that generates a coverage extension signal so that a data portion included in the coverage extension signal is transmitted robustly, and a transmission circuit that transmits the generated coverage extension signal.

[0007] A wireless receiving device according to an embodiment of the present disclosure includes a receiving unit that receives a coverage extension signal including a robustly transmitted data portion, and a control circuit that decodes the data portion.

[0008] A communication method according to an embodiment of the present disclosure generates a coverage extension signal such that a data portion included in the coverage extension signal is transmitted robustly, and transmits the generated coverage extension signal.

[0009] A communication method according to an embodiment of the present disclosure includes receiving a coverage extension signal including a robustly transmitted data portion and decoding the data portion.

[0010] These comprehensive or specific aspects may be realized as a system, an apparatus, a method, an integrated circuit, a computer program, or a recording medium, or may be realized as any combination of a system, an apparatus, a method, an integrated circuit, a computer program, and a recording medium.

[0011] According to an embodiment of the present disclosure, coverage extension signals in wireless communication can be appropriately transmitted and received.

[0012] Further advantages and benefits of one embodiment of the present disclosure will become apparent from the specification and drawings. Such advantages and / or benefits may be provided by some embodiments and features described in the specification and drawings, respectively, but not necessarily all of them may be provided to obtain one or more identical features.

[0013] Diagram showing an example of ELR SU PPDU formatDiagram showing an example of ELR SU PPDU formatDiagram showing an example of Tone allocation when DRU is applied to the data sectionBlock diagram showing an example of the configuration of part of a terminal (communication device)Block diagram showing an example of the configuration of part of an APBlock diagram showing the main configuration of a terminalBlock diagram showing the main configuration of an APDiagram showing the U-SIG fieldDiagram showing the EHT-SIG fieldDiagram showing integrated UHR-SIGDiagram showing the U-SIG fieldDiagram showing the EHT-SIG fieldDiagram showing an example of Tone allocation when DRU and DCM are appliedDiagram showing an example of Tone allocationDiagram showing an example of Tone allocationDiagram showing an example of Tone allocation when coding rate 1 / 8 is applied with BPSK

[0014] Hereinafter, each embodiment of the present disclosure will be described in detail with reference to the drawings.

[0015] In this embodiment, a communication device is described that generates a coverage extension signal so that a data portion included in the coverage extension signal is transmitted robustly, and transmits the generated coverage extension signal. In this embodiment, an ELR (Enhanced Long Range) SU (Single User) PPDU (Physical Layer Protocol Data Unit) is used as an example of the coverage extension signal. Note that an ELR SU PPDU refers to a PPDU that transmits an SU signal by extending one of the fields L-STF, L-LTF, L-SIG, U-SIG, or UHR-SIG, which will be described later. Furthermore, UHR-SIG is the name of a field that includes control information for 11bn (UHR). While the name may be different in versions after 11bn, this field will be referred to as UHR-SIG for convenience in this embodiment.

[0016] First, the above-mentioned extensions will be explained. Improved coverage performance is required for 11bn (see, for example, Non-Patent Documents 1-3). In particular, because access points (also called "APs (Access Points)" or "base stations") have a higher maximum transmission power than terminals (also called "STAs (Stations)" or "non-AP STAs"), UL coverage performance is worse than DL coverage performance, and the need for improving UL coverage performance is being considered.

[0017] IEEE 802.11ax (hereinafter referred to as "11ax") supports HE ER (extended range) SU PPDU to improve coverage performance (see, for example, Non-Patent Document 5).

[0018] In the ELR SU PPDU, the field is extended to improve the coverage performance of the preamble. Field extension refers to power boost, which increases the transmission power by a predetermined amount (e.g., 3 dB) compared to other fields, or repetition, which repeats the signal a predetermined number of symbols in the time domain or frequency domain. Coverage performance is improved by transmitting some fields that are bottlenecks in terms of performance using an extended ELR SU PPDU format.

[0019] For example, the L-STF field and L-LTF field, which are bottlenecks in reception performance, are power-boosted. Also, the L-SIG field and HE-SIG-A field, which contain control information for decoding data, are transmitted in the time domain with repetition.

[0020] Non-Patent Document 4 considers an extended coverage preamble (ELR preamble) for 11bn. With the ELR preamble, it is considered to extend the 11bn field (U-SIG, etc.), which is a bottleneck in reception performance.

[0021] An example of the extended ELR SU PPDU format will be described in detail below. Figures 1 and 2 show an example of the ELR SU PPDU format.

[0022] Each field shown in Figures 1 and 2 will be explained below. The L-STF (Legacy Short Training Field) and L-LTF (Legacy Long Training Field) are located at the beginning of the frame and contain information that allows the receiver to perform frequency offset estimation, timing synchronization, and signal detection. The L-SIG (Legacy Signal Field) provides information that allows the receiver to determine the length and transmission speed (data rate) of the following frame. The U-SIG (Universal Signal Field) and UHR-SIG (Ultra High Reliability Signal Field) provide information for decoding data, such as the length of the following user-specific data section.

[0023] The UHR-STF (Ultra High Reliability - Short Training Field) is used for automatic gain control (AGC) distortion reduction or timing detection. It also provides initial information for estimating channel characteristics. The UHR-LTF (Ultra High Reliability - Long Training Field) provides more detailed channel state information. This allows the receiving terminal to compensate for the channel effects and accurately demodulate the signal. The DATA field stores the data to be transmitted and indicates the data section to be transmitted robustly. The PE (Packet Extension) indicates the end of the frame and is used by the receiving terminal to recognize the end of the frame. It also provides the interval until the start of the next frame (Interframe Space).

[0024] Based on the above, an example of an ELR SU PPDU format shown in Figures 1 and 2 will be described. The example of the ELR SU PPDU format shown in Figure 1 shows an ELR SU PPDU format in which L-STF and L-LTF are power-boosted and L-SIG and U-SIG (a field consisting of two OFDM (Orthogonal Frequency Division Multiplexing) symbols, U-SIG-1 and U-SIG-2) are repeated.

[0025] Figure 2 shows an ELR SU PPDU format in which a UHR-SIG (a field consisting of two OFDM symbols, UHR-SIG-1 and UHR-SIG-2) containing UHR version-specific control information is added to the example ELR SU PPDU format in Figure 1 and then repeated.

[0026] Note that the preamble in this embodiment refers to the signal before UHR-STF in the example ELR SU PPDU format shown in Figures 1 and 2 (from L-STF to U-SIG in Figure 1, and from L-STF to UHR-SIG in Figure 2). Note that in the example ELR SU PPDU format shown in Figures 1 and 2, U-SIG and UHR-SIG are repetitively repeated twice in the time direction, but this is not limited to this, and repetition more than twice (for example, four times) may be applied. Furthermore, repetition in the frequency direction may be applied, in which signals are repeatedly allocated to frequency resources. Furthermore, the number of repetitions for U-SIG and UHR-SIG may be different.

[0027] As described above, in this embodiment, the frame is extended as specified in 11ax or the like, and then the data portion is robustly transmitted. This embodiment includes an embodiment (referred to as a "first embodiment") in which robust transmission is performed by applying a Distributed-tone RU (hereinafter referred to as a "DRU") to the data portion, and an embodiment (referred to as a "second embodiment") in which transmission is performed using the entire PPDU band using low-rate coding. The first embodiment will be described.

[0028] <First embodiment> DRU refers to an RU in which tones that allocate data in a predetermined bandwidth (e.g., PPDU BW) are discretely (or dispersedly or spreadly) arranged. Fig. 3 is a diagram showing an example of tone arrangement when DRU is applied to a data section. The application example shown in Fig. 3 is an example in which 26 tones of data are dispersedly arranged at 9-tone intervals in a 20 MHz PPDU BW. The data section may be transmitted using tones that are discretely arranged in the bandwidth in this way.

[0029] In contrast to this DRU, the conventional 11ax HE ER SU PPDU uses a Regular RU (hereinafter referred to as "RRU"), which arranges tones consecutively in the bandwidth, i.e., allocates data to multiple consecutive tones. In this embodiment, a form in which a DRU is applied as described above will be described, but an example in which an RRU is partially applied will also be described. Note that, since the RRU is subject to PSD limitations, in this embodiment, only an MCS that is more robust than that of the DRU is used (for example, the RRU uses only MCS0+DCM).

[0030] In wireless LANs, there are regulations that limit the transmission power density (PSD: Power Spectrum Density) to a specified value. For example, in the 2.4 GHz and 5 GHz bands, regulations in Japan, Europe, and China limit PSD to 10 dBm / MHz or less. In addition, there are regulations that limit PSD to -1 dBm / MHz for LPI (Low Power Indoor) terminals in the 6 GHz band.

[0031] The smaller the number of tones, the higher the SNR (Signal to Noise Ratio) per tone, which is expected to improve coverage performance. However, when an RRU with a small number of tones is used in an environment with PSD regulations, the transmission power is limited, which limits coverage performance.

[0032] For example, when transmitting 52 tones using an RRU (with a bandwidth of approximately 4 MHz), in an environment with a PSD regulation of 10 dBm / MHz or less, the transmission power is limited to approximately 16 dBm or less. If this transmission power is smaller than the maximum transmission power of the terminal, the coverage performance will be limited.

[0033] Therefore, in this embodiment, by applying DRU to the data section of the ELR SU PPDU, the tones to which data is assigned are distributed, reducing the number of tones per 1 MHz, thereby improving the SNR per tone even when the number of tones is small. This DRU power boost gain (the increase in transmission power when DRU is applied relative to the transmission power when RRU is applied) can improve coverage performance.

[0034] [Configuration of Wireless Communication System] The wireless communication system according to this embodiment may include, for example, a terminal 100 (e.g., a communication device) and an AP 200 (e.g., a wireless receiving device). In the wireless communication system, there may be two or more terminals 100.

[0035] 4 is a block diagram illustrating an example configuration of a portion of a terminal 100 according to an embodiment of the present disclosure. In the terminal 100 illustrated in FIG. 4, a communication unit (e.g., corresponding to a transmission circuit) transmits an ELR SU PPDU. A control unit 101 (e.g., corresponding to a control circuit) generates the ELR SU PPDU so that a data portion included in the ELR SU PPDU is robustly transmitted by the communication unit.

[0036] 5 is a block diagram illustrating a partial configuration example of an AP 200 according to an embodiment of the present disclosure. As described above, the terminal 100 transmits an ELR SU PPDU to the AP 200, and the communication unit 200 (e.g., corresponding to a receiving circuit) of the AP 200 receives the coverage extension signal including the robustly transmitted data portion. The control unit 200 (e.g., corresponding to a control circuit) then decodes the data portion. This improves UL coverage performance and ensures data reliability.

[0037] The transmitting and receiving sides may be interchanged, with the receiving side being the terminal and the transmitting side being the AP. For example, an AP having the configuration of terminal 100 may transmit an ELR SU PPDU to a terminal having the configuration of AP 200, and the terminal may receive the ELR SU PPDU. This improves DL coverage performance. The ELR SU PPDU applies DRU to frequency resource allocation for the data section, and includes DRU frequency resource information in the preamble.

[0038] 6 is a block diagram showing the main configuration of the terminal 100 according to this embodiment. The terminal 100 generates an ELR SU PPDU for the AP 200 and transmits the generated ELR SU PPDU to the AP 200.

[0039] The control unit 101 performs control for generating a PPDU to be transmitted to the AP 200. For example, the control unit 101 determines a coding method (e.g., BCC (Binary Convolutional Coding) or LDPC (Low Density Parity Check)), a coding rate, a modulation method (e.g., BPSK, QPSK, 16QAM), and a transmission resource (e.g., an allocated frequency) for the data of the ELR SU PPDU to be transmitted to the AP 200, and outputs the determined data to the error correction coding unit 102, the modulation unit 103, and the Tone mapping unit 104.

[0040] The control unit 101 determines the coding rate and modulation method from an MCS table (a table that defines the coding rate and modulation method for each MCS number) defined in the specifications. The control unit 101 also outputs control information required for the AP 200 to decode the ELR SU PPDU to the preamble generation unit 105.

[0041] The transmission resource information may include, for example, information indicating the RU type (e.g., information indicating either a DRU or an RRU) and information indicating the RU size (number of tones). For example, a Tone allocation (Tone start position, Tone interval, Tone end position) uniquely determined from the RU type and number of tones is defined in advance in a specification. As a result, the terminal 100 (transmitter) notifies the AP 200 (receiving side) of the RU type and number of tones, allowing the AP 200 to acquire data transmission resources. Note that, when the PPDU BW is limited to a predetermined value or less (e.g., 20 MHz or less) in the ELR SU PPDU, the distribution bandwidth in which the DRU tones are allocated may be the same as the PPDU BW. In other words, the bandwidth in which tones are allocated when a DRU is applied to the data section may be limited to a predetermined bandwidth or less.

[0042] The error correction coding unit 102 receives the transmission data from the terminal 100 and the coding method and coding rate from the control unit 101, performs error correction coding on the transmission data using the input coding method and coding rate, and outputs the coded signal to the modulation unit 103.

[0043] The modulation section 103 performs modulation processing on the signal input from the error correction coding section 102 based on the modulation method input from the control section 101 , and outputs the modulated data signal to the tone mapping section 104 .

[0044] The STF / LTF generating unit 106 generates a UHR-STF signal (reference signal for AGC (Automatic Gain Control) control) and a UHR-LTF signal (reference signal for data demodulation) using a predetermined data sequence, and outputs the generated UHR-STF / UHR-LTF signal to the Tone mapping unit 104. Note that, although "UHR" refers to STF / LTF for 11bn in this embodiment, the names may be different for versions after 11bn.

[0045] Based on the transmission resource information input from the control unit 101, the Tone mapping unit 104 maps the modulated signal input from the modulation unit 103 and the UHR-STF / UHR-LTF signal input from the STF / LTF generation unit 106 to predetermined Tone positions and outputs them to the OFDM modulation unit 107.

[0046] For example, when RRU is specified as the transmission resource information, data is allocated to consecutive tones, and when DRU is specified as the transmission resource information, data is allocated to discrete tones.

[0047] The rules for the transmission resources (tone allocation) of UHR-LTF and UHR-STF are defined in advance in the specifications. In other words, the position at which tones are allocated when DRU is applied to the data section may be a fixed value. For example, the transmission resources (tone allocation) of UHR-LTF and UHR-STF may be the same as the tone allocation of data. Alternatively, they may be allocated within the PPDU BW at a specified tone interval in an arrangement different from the tone allocation of data (an arrangement that includes tones where no data is allocated). Furthermore, UHR-LTF may have the same tone allocation as data, while UHR-STF may have a different tone allocation from data.

[0048] The OFDM modulation unit 107 performs an inverse fast Fourier transform (IFFT) process on the modulated signal after mapping from the tone mapping unit 104, and adds a cyclic prefix (CP) to form an OFDM signal, and outputs the OFDM signal to the radio transmission / reception unit 108.

[0049] The preamble generation unit 105 generates signals other than the data portion, PE (packet extension), UHR-STF, and UHR-LTF (reference signals for data decoding) in the ELR SU PPDU. For example, in the example of Fig. 1, the preamble generation unit 105 generates signals from L-STF to U-SIG, and in the example of Fig. 2, the preamble generation unit 105 generates signals from L-STF to UHR-SIG.

[0050] Preamble generation section 105 receives control information required for data decoding from control section 101, converts the control information into a predetermined format (for example, the ELR SU PPDU format example shown in FIGS. 1 and 2), and generates a preamble signal. Preamble generation section 105 outputs the generated preamble signal to radio transmission / reception section 108.

[0051] The wireless transceiver 108 combines the preamble signal input from the preamble generator 105 and the OFDM signal input from the OFDM modulator 107 to generate an ELR SU PPDU signal. The wireless transceiver 108 then performs predetermined wireless transmission processing, such as D / A (digital-to-analog) conversion and upconversion to a carrier frequency, on the generated ERL SU PPDU signal, and transmits the signal after wireless transmission processing to the AP 200 via an antenna. The wireless transceiver 108 robustly transmits the data portion, and further, when applying power boost to some fields of the preamble (e.g., L-STF, L-LTF), increases the transmission power of those fields by a predetermined value (e.g., 3 dB) before transmission.

[0052] [AP Configuration] Fig. 7 is a block diagram showing the main configuration of AP 200 according to this embodiment. In Fig. 7, wireless transmission / reception section 201 receives a signal via an antenna, performs wireless reception processing such as down-conversion and A / D conversion on the received signal, extracts a preamble portion from the obtained received signal (ELR SU PPDU from terminal 100), and outputs the extracted preamble portion to preamble decoding section 202. Wireless transmission / reception section 201 also outputs signals other than the preamble portion (UHR-STF, UHR-LTF, Data, PE, etc.) to OFDM demodulation section 203.

[0053] The preamble decoding unit 202 decodes the control information required for data decoding from the preamble signal generated in a predetermined format, and outputs the decoded control information to the tone demapping unit 204, the demodulation unit 205, and the error correction decoding unit 206.

[0054] The OFDM demodulation unit 203 performs, for example, OFDM demodulation processing on the signal input from the wireless transmission / reception unit 201, and executes received signal processing related to OFDM. The OFDM demodulation unit 203 performs, for example, CP removal processing and Fast Fourier Transform (FFT) processing, and outputs the processed signal to the Tone demapping unit 204.

[0055] Based on the control information (such as transmission resource information) input from the preamble decoding unit 202, the tone demapping unit 204 acquires the received signal at a predetermined tone position where data is allocated from the received signal input from the OFDM demodulation unit 203, and outputs the signal to the demodulation unit 205.

[0056] Based on the control information (modulation method, etc.) input from the preamble decoding unit 202, the demodulation unit 205 performs corresponding demodulation processing (channel estimation, frequency domain equalization processing, etc.) on the received signal input from the tone demapping unit 204, and outputs the result of the demodulation processing to the error correction decoding unit 206.

[0057] The error correction decoding unit 206 performs error correction decoding on the received signal input from the demodulation unit 205 based on the control information (encoding method, encoding rate, etc.) input from the preamble decoding unit 202, and outputs the decoded signal as received data.

[0058] [Specific Example of ELR SU PPDU Format] Next, a description will be given of an example of the format of the ELR SU PPDU transmitted from the terminal 100 to the AP 200 in the case of robust transmission in this embodiment.

[0059] [Specific Example 1 of ELR SU PPDU Format] First, the format defined in IEEE 802.11be (hereinafter referred to as "11be") will be described. In the EHT MU PPDU format defined in 11be (EHT), a U-SIG field and an EHT-SIG field are defined as fields containing control information for decoding data. Fig. 8 is a diagram showing the U-SIG field. Fig. 9 is a diagram showing the EHT-SIG field.

[0060] In FIG. 8, "Two Parts of U-SIG" indicates U-SIG-1 and U-SIG-2. In FIG. 9, "UHR-SIG" indicates Common (U-SIG overflow bis) and User field, etc. In FIG. 8 and FIG. 9, "Bit" indicates the bit number assigned to the field. "Field" indicates the field name. "Number of bits" indicates the number of bits assigned to the field.

[0061] 8 and 9 indicate fields to be deleted (hereinafter referred to as "fields to be deleted") when applying the EHT MU PPDU format defined in 11be (EHT) to this embodiment. In specific example 1, the fields to be deleted are deleted and the remaining fields are integrated.

[0062] Fig. 10 is a diagram showing an integrated UHR-SIG in which the remaining fields have been integrated. The shaded areas in Fig. 10 are fields that have been integrated into the empty fields that were created by deleting the shaded areas in Fig. 8. The integrated fields are fields other than the fields to be deleted shown in Fig. 9.

[0063] In Example 1, the fields to be deleted can be deleted by setting a fixed value to the field. For example, the bandwidth of the ELR SU PPDU (PPDU BW) is limited to 20 MHz. This allows the Punctured Channel Indication field (information indicating non-transmission bands in 20 MHz channel units) shown in Figure 8 to be deleted.

[0064] The wider the bandwidth, the lower the transmission power per tone, which leads to a decrease in coverage performance. Therefore, for ELR SU PPDUs, which are intended to improve coverage performance, limiting the bandwidth to the minimum value (20 MHz) has little impact on performance.

[0065] Furthermore, by limiting to SU (Single User) PPDU and not supporting OFDMA multiplexing, it is possible to delete the PPDU type & Compression Mode field (information indicating the PPDU type, such as whether or not OFDMA is present) shown in FIG. 8 and the Number Of Non-OFDMA Users field (information indicating the number of spatially multiplexed users) shown in FIG. 9.

[0066] Similarly, by limiting the data to a single user, the MAC address of the receiving party is notified in the RA (Receiver Address) field of the MAC header of the data, so the STA-ID (terminal association ID) in FIG. 9 can be deleted.

[0067] Furthermore, by limiting the MCS patterns applicable to the ELR SU PPDU, the size of the MCS field can be reduced. For example, 4 bits are allocated to the MCS field (B31-B34) shown in Fig. 9, but in Example 1, as shown in Fig. 10, the MCS field (B7-B9) after aggregation is reduced to 3 bits.

[0068] Furthermore, by limiting the number of spatial streams applicable to the ELR SU PPDU to one, the NSS field (information indicating the number of spatial streams) in Fig. 9 can be deleted. When the reception quality of data is low, using two or more spatial streams becomes difficult in terms of performance. Since the reception quality is low in the environment in which the ELR SU PPDU is used, limiting the number of spatial streams to one has little impact on performance.

[0069] Furthermore, as shown in Figure 10, by integrating into one U-SIG field and deleting the EHT-SIG field, it is possible to delete the EHT-SIG MCS field (information indicating the MCS to be applied to the data in the EHT-SIG field) and the Number of EHT-SIG symbols (information indicating the number of OFDM symbols in the EHT-SIG field) shown in Figure 8.

[0070] Next, an example of parameters (values) set in the integrated U-SIG field shown in Fig. 10 will be described. In the following description, parameters will be described using the expression X:Y, where X indicates the parameter and Y indicates the content corresponding to parameter X. For example, 0:EHT indicates that when the parameter is 0, it is EHT.

[0071] The Version Identifier field may define a parameter indicating the PHY version after EHT as follows: set to 0 for EHT or UHR set to 1 for UHR ELR Values ​​2-7 are Validate

[0072] In the above definition, a value of 0 indicates EHT or UHR (indicating that the same format is applied to both EHT and UHR), and a value of 1 may indicate UHR ELR. As in the case of a value of 1, the PHY version (UHR) and PPDU format type (ELR) may be combined to indicate this. In this way, the PHY Version Identifier field included in the ELR SU PPDU is used to indicate that the PPDU is for ELR.

[0073] Alternatively, if the Version Identifier is 0, the parameters can be defined as follows, separating EHT and UHR. In this case, if the value is other than 0, the EHT terminal can stop subsequent reception processing, thereby reducing terminal power consumption. set to 0 for EHT set to 1 for UHR set to 2 for UHR ELR Values ​​3-7 are Validate

[0074] In the Bandwidth field, the parameter indicating the data frequency resource allocation information may be defined as follows: set to 0 for 242-tone RU set to 1 for 106-tone RRU set to 2 for 52-tone RRU set to 3 for 26-tone RRU set to 4 for 106-tone DRU set to 5 for 52-tone DRU set to 6 for 26-tone DRU Values ​​7 is Validate

[0075] In the above definition, values ​​0-3 indicate RRU, and values ​​4-6 indicate DRU. Defining the Tone placement for each Tone number in the specifications makes further notification unnecessary. Also, by limiting it to Single User, OFDMA is not supported, so notification of the Tone start position (also called Tone offset) assuming User multiplexing is unnecessary. Also, limiting the PPDU BW to 20 MHz makes further notification of Distribution bandwidth, etc. unnecessary.

[0076] In the MCS field, if UHR ELR is indicated in the PHY Version Identifier field, the parameter indicating the MCS to be applied to data may be defined as follows: set to 0 for MCS 0 (BPSK 1 / 2) + DCM set to 1 for MCS 0 (BPSK 1 / 2) set to 2 for MCS 1 (QPSK 1 / 2) + DCM set to 3 for MCS 1 (QPSK 1 / 2) set to 4 for MCS 2 (QPSK 3 / 4) + DCM set to 5 for MCS 2 (QPSK 3 / 4) Values ​​6-7 are Validate

[0077] In the above definition, the modulation method is limited to BPSK and QPSK, which have strong error tolerance. Furthermore, values ​​of 0, 2, and 4 apply DCM (Dual Carrier Modulation). DCM is a process in which the same data is replicated across two bands and placed in the frequency domain. This has the advantage of improving communication reliability, as even if communication quality deteriorates in one band due to interference, it can still be received correctly in the other band. In this way, robust transmission can use tones that are discretely placed across the bandwidth, and the data portion can be transmitted using DCM.

[0078] Next, a coverage extension example applied to the ELR SU PPDU format shown in Figure 1 when specific example 1 is applied will be described. As explained in Figure 1 and other figures, a power boost of a predetermined value (e.g., 3 dB) is applied to the L-STF field and L-LTF field. Furthermore, time domain repetition is applied to the L-SIG field. In Figure 1, two symbols are transmitted with repetition, but this is not limiting, and the number of repetitions may be increased, for example, to four symbols.

[0079] Here, as with 11ax, the value of the L-SIG LENGTH field (whether the LENGTH value mod 3 is 0 or not) determines whether the field following the L-SIG field is a U-SIG or an HE-SIG-A (field for 11ax). In the ELR SU PPDU for 11bn, the value of the LENGTH field is controlled to indicate that the field following the L-SIG field is a U-SIG field. The U-SIG field consists of two symbols, the U-SIG-1 field and the U-SIG-2 field, and time domain repetition is applied to each. As mentioned above, there is no limit on the number of repetitions.

[0080] Here, the transmitting side implicitly notifies the receiving side whether or not repetition is applied to the U-SIG field by changing the mapping method to the IQ axis of the U-SIG-1 field in the first symbol and the U-SIG-1-R field in the second symbol. For example, as with 11ax, the application of repetition to the U-SIG field can be indicated by setting the mapping method for the first and second symbols to BPSK and QBPSK.

[0081] The receiving side determines how to decode the U-SIG field by determining the mapping method (BPSK or QBPSK) for the second symbol. For example, if the mapping method for the second symbol is QBPSK, it is determined to be a U-SIG field with repetition (ELR SU PPDU format) and decoding is performed. If the mapping method for the second symbol is BPSK, it is determined to be a U-SIG field without repetition (for example, a UHR MU PPDU format that is not ELR) and decoding is performed. Note that, as mentioned above, U-SIG repetition transmission is not limited to two times.

[0082] [ELR SU PPDU Format: Modification of Specific Example 1] In Specific Example 1, whether or not the PPDU is ELR is notified as a PPDU format type in the PHY Version Identifier field of FIG. 10 , but the information on whether or not the PPDU is ELR may be indicated in association with the repetition number in the U-SIG field. For example, a repetition number greater than 1 (repeated transmission of 2 or more symbols) indicates an ELR (UHR ELR SU PPDU) format, and a repetition number of 1 (no repeated transmission) indicates a format other than ELR (e.g., UHR MU PPDU). In this way, if the repetition number in the U-SIG field is greater than 1, it can indicate an ELR format, making the information on whether or not the PPDU is ELR unnecessary in the PHY Version Identifier field. In this case, the PHY Version Identifier field in FIG. 7 may be defined, for example, as follows: set to 0 for EHT set to 1 for UHR Values ​​2-7 are Validate

[0083] If the repetition count in the U-SIG field indicates the format for ELR, the U-SIG field may be defined for ELR. In this case, all field information in the U-SIG field is defined for ELR, and there is no need to condition whether it is ELR or not.

[0084] Also, when specifying whether the format is for ELR or not by the repetition number of the U-SIG field, the definition of the PHY Version Identifier field may be different for ELR and non-ELR. For example, the PHY Version Identifier field for ELR is defined as follows: set to 1 for UHR Values ​​0, 2-7 are Validate

[0085] The EHT version does not define the PPDU format for ELR (for extended coverage performance). Therefore, if a value other than UHR with a value of 1 is specified (if Validate is specified), the UHR terminal may determine that the format is unknown (for example, a format for a future standard (standard after UHR)) and stop receiving the PPDU.

[0086] The PHY Version Identifier field for non-ELR is defined as follows: set to 0 for EHT set to 1 for UHR Values ​​2-7 are Validate

[0087] UHR terminals are able to receive UHR and earlier EHT versions because they understand the PPDU format. Therefore, UHR terminals determine that a value of 0 indicates an EHT version PPDU format and a value of 1 indicates a UHR version PPDU format other than that for ELR, and perform reception processing accordingly.

[0088] [Specific example 2 of ELR SU PPDU format] In specific example 1, some fields of the EHT MU PPDU format specified in 11be (EHT) were deleted and integrated, but in specific example 2, the EHT MU PPDU format specified in 11be (EHT) is reused and some of the U-SIG field and EHT-SIG field are defined again.

[0089] Fig. 11 is a diagram showing a U-SIG field in specific example 2. The shaded portion in Fig. 11 indicates a field newly defined from the U-SIG field shown in Fig. 8. Fig. 12 is a diagram showing an EHT-SIG field in specific example 2. The shaded portion in Fig. 12 indicates a field newly defined from the EHT-SIG field shown in Fig. 9.

[0090] The PHY Version Identifier field in FIG. 11 may be defined, for example, as follows: set to 0 for EHT set to 1 for UHR Values ​​2-7 are Validate

[0091] The PPDU type & Compression Mode field in Fig. 11 may be defined, for example, as follows: A value of 3 indicates that the PPDU type is ELR, set to 0 for OFDMA, set to 1 for SU, or sounding NDP, set to 2 for non-OFDMA, and set to 3 for ELR.

[0092] 12 may be defined as follows, for example, in the same way as in Example 1, when the PPDU type is ELR SU: set to 0 for MCS 0 (BPSK 1 / 2) + DCM set to 1 for MCS 0 (BPSK 1 / 2) set to 2 for MCS 1 (QPSK 1 / 2) + DCM set to 3 for MCS 1 (QPSK 1 / 2) set to 4 for MCS 2 (QPSK 3 / 4) + DCM set to 5 for MCS 2 (QPSK 3 / 4) Values ​​6-15 are Validate Considering cases where the PPDU type is other than ELR, the MCS field cannot be reduced to 3 bits as in Example 1, but the number of testing man-hours can be reduced by limiting the MCS patterns in the case of ELR.

[0093] In the NSS field in Fig. 12, when the PPDU type is ELR SU, the number of spatial streams may be limited to 1, for example, as in Example 1. For types other than ELR, the same number of SSs as in 11be may be applied. set to 0 for 1 Values ​​1-15 are Validate Considering cases where the PPDU type is other than ELR, the NSS field cannot be deleted as in Example 1, but the number of test steps can be reduced.

[0094] Next, we will explain coverage extension control applied to the ELR SU PPDU format in Figure 2 when Example 2 is applied. As with Example 1, a power boost of a predetermined value (e.g., 3 dB) is applied to the L-STF field and L-LTF field, and time domain repetition is applied to the L-SIG field. The value of the LENGTH field of the L-SIG indicates that the field following the L-SIG field is a U-SIG field. In addition, the repetition number of the U-SIG field is indicated by changing the mapping method to the IQ axis of the U-SIG-1 field in the first symbol and the U-SIG-1-R field in the second symbol.

[0095] In specific example 2, the repetition in the time domain is also applied to the UHR-SIG field. The number of repetitions of the UHR-SIG is notified, for example, in the Number of EHT-SIG symbols field of the U-SIG field.

[0096] In addition, in specific example 2, the STA-ID field is indicated in the UHR-SIG. By notifying the STA-ID, the receiving side can immediately determine whether a packet is addressed to itself by decoding the preamble without decoding the MAC header. For example, in the case of a non-STR (Simultaneous Transmit and Receive) terminal with multiple links (a terminal that cannot transmit and receive simultaneously on multiple links), if it can immediately determine that a packet is not addressed to itself on link A, for example, carrier sense on link B can be immediately performed, thereby improving performance over multiple links.

[0097] As described in the modified example of the first specific example, whether or not there is an ELR may be indicated in association with the repetition number of the U-SIG field. In this case, the PPDU type & Compression Mode field in Fig. 11 may be defined as follows, for example. Since the ELR can be notified by the repetition number of the U-SIG field, there is no need to notify in this field. set to 0 for OFDMA set to 1 for SU or sounding NDP set to 2 for non-OFDMA set to 3 for Validate

[0098] By defining the above-mentioned ELR SU PPDU format and applying DRU to robustly transmit the data portion, coverage performance can be improved even when a small number of tones is used. Furthermore, allocating a small number of tones can improve the SNR per tone. This allows the use of DRU to increase transmission power and improve coverage performance even in environments where PSD is specified. Furthermore, overhead can be reduced by restricting some transmission parameters (such as PPDU BW and frequency lease allocation pattern) in the ELR SU PPDU.

[0099] [Example of Application of DRU and DCM] Next, a specific example will be described in which DRU is applied to the data section in the ELR SU PPDU format, and DCM is also applied.

[0100] Fig. 13 is a diagram showing an example of Tone arrangement when DRU and DCM are applied. In Fig. 13, the horizontal axis represents frequency and the vertical axis represents PSD. The same applies to the vertical and horizontal axes of the graphs in Figs. 14 to 17 described below.

[0101] The arrangement example shown in Fig. 13 shows a tone arrangement of data in which DCM is applied to 26 tone data, resulting in 52 tones. Data for each tone is arranged (copied) to adjacent tones, with different modulation mapping methods applied.

[0102] For example, in the case of BPSK modulated data, data with the sign of the IQ axis data inverted is copied to an adjacent tone. In this way, by changing the modulation mapping method of the copied data, it is possible to reduce the PAPR (Peak to Average Power Ratio) when DCM is applied to the DRU. In addition, the UHR-LTF, which is a reference signal for data demodulation, is placed in the same tone as the data shown in Figure 13.

[0103] In this way, allocating one piece of data to multiple tones improves data reception performance. Furthermore, by arranging UHR-LTF tones contiguously, the reference signals between the tones can be averaged, improving channel estimation accuracy. Because channel estimation accuracy significantly affects reception performance, especially in low SNR regions, improving channel estimation accuracy can also improve coverage performance.

[0104] [Example of DRU Application] Next, we will explain a specific example of tone allocation when applying DRU to data in the ELR SU PPDU format. For example, as with the DRU of the TB PPDU (Trigger frame response PPDU), assuming OFDMA multiplexing among multiple terminals, it is possible to define an equally spaced tone allocation excluding the DC tones (multiple tones in the center) that have significant interference, in order to reduce unused tones as much as possible and define the tone allocation for each terminal.

[0105] Figure 14 shows an example of tones allocation excluding the central tones. In Figure 14, data is allocated at intervals of 9 tones, excluding the DC tone (the central 7 tones in the figure). In this case, as shown in Figure 14, there are some locations where the tones are physically spaced 9 tones and some where they are spaced 16 tones apart, so the tones are not physically spaced equally.

[0106] Figure 15 shows an example of how DRU tones are arranged in an ELR SU PPDU. As shown in Figure 15, tones are allocated at equal intervals, including the DC tone. For example, in the case of a PPDU BW = 20 MHz and a 26-tone DRU, the RU tone definition is arranged as [-112, 9, 113] or [-113, 9, 112]. Here, the numbers in parentheses indicate the [start tone number, tone interval, and end tone number], respectively.

[0107] Only two patterns can be defined for a 26-tone DRU that is not allocated to the central seven tones and is physically spaced equally, but this does not pose a problem if it is limited to a single-user PPDU that does not assume OFDMA multiplexing. Similarly, a 52-tone DRU in an ELR SU PPDU uses a tone arrangement that allocates tones at intervals of four tones, and does not allocate the central three tones (DC tones). In this way, the PAPR can be reduced by physically allocating DRU tones at equal intervals in an ELR SU PPDU.

[0108] [Specific Example of Preamble] Next, a specific example of a preamble when applying RRU or DRU to the data section in the ELR SU PPDU format will be described.

[0109] The control information (such as the control range) notified in the preamble may be changed depending on whether a DRU is applied to the data section or an RRU is applied. For example, the upper limit on the number of UHR-STF and UHR-LTF symbols may be changed. Since the average number between consecutive tones is smaller for a DRU than for an RRU, it is conceivable that the channel estimation accuracy may be worse. Therefore, the upper limit on the number of UHR-STF / LTF symbols when a DRU is applied may be increased.

[0110] For example, the Number Of EHT-LTF Symbols field in the U-SIG of the ELR SU PPDU shown in Fig. 10 indicates the number of UHR-LTF symbols, but when a UHR ELR is indicated, it may be defined as follows, for example: - When the EHT SU PPDU is an RRU, the number of EHT-LTF symbols is 1, 2, 4, 6, 8, 10, 12, or 14. - When the EHT SU PPDU is a DRU, the number of EHT-LTF symbols is 1, 2, 4, 6, 8, 12, 16, or 20.

[0111] When instructing an RRU, the upper limit of the number of EHT-LTF symbols is 14. When instructing a DRU, the upper limit of the number of EHT-LTF symbols is 20. In this way, the coverage performance can be improved because the appropriate transmission method can be instructed depending on the RRU and DRU. In addition, overhead does not increase.

[0112] Second Embodiment As a transmission example when a data portion is robustly transmitted, an example of an ELR SU PPDU transmission method will be described, in which coverage performance is improved by transmitting the data portion across the entire PPDU band using coding at a lower rate than the coding rate of the MCS used for other PPDU types (e.g., HE PPDU, etc.). In this way, an MCS using a coding rate lower than a predetermined coding rate (the coding rate of the MCS used for other PPDU types) may be applied to the data portion.

[0113] [Configuration of Wireless Communication System] A wireless communication system using low-rate encoding may include, for example, a terminal 100 (e.g., a communication device) and an AP 200 (e.g., a wireless receiving device), similar to the wireless communication system described above. Two or more terminals 100 may be present in the wireless communication system.

[0114] [Terminal Configuration] The block diagram of the terminal 100 when using low-rate coding is the same as that shown in FIG. 6, but the operations of the error correction coding unit 102 and the Tone mapping unit 104 are different. The operation of the error correction coding unit 102 differs in the coding rate used for the ELR SU PPDU. When using low-rate coding, the coding rate used for the ELR SU PPDU is lower than that of other switchable PPDU types (for example, PPDU types other than ELR (UHR MU PPDU, etc.)).

[0115] The operation of the Tone mapping unit 104 differs depending on the frequency domain repetition number used for the ELR SU PPDU. When low-rate coding is used, the frequency domain repetition number used for the ELR SU PPDU is greater than that used for other PPDU types to allocate data.

[0116] [AP Configuration] The block diagram of AP 200 when low-rate coding is used is the same as that shown in Figure 7, but the operations of error correction decoding unit 206 and Tone demapping unit 204 are different. The operation of error correction decoding unit 206 differs depending on the coding rate used for ELR SU PPDU. When low-rate coding is used, data is decoded using a coding rate that is lower for ELR SU PPDU than for other PPDU types.

[0117] The operation of the tone demapping unit 204 differs depending on the frequency domain repetition number used for the ELR SU PPDU. When low-rate coding is used, data using a frequency domain repetition number greater than that used for other PPDU types is extracted and combined.

[0118] [Example of ELR SU PPDU format] Each field in the PPDU format is explained in detail below. When the Version Identifier is ELR PPDU, the Bandwidth field in U-SIG-1 may be defined as follows, for example: set to 0 for 242-tone RU set to 1 for 106-tone RRU set to 2 for 52-tone RRU set to 3 for 26-tone RRU set to 4 for 106-tone + 2 repetition set to 5 for 52-tone + 4 repetition set to 6 for 26-tone + 9 repetition Values ​​7 is Validate

[0119] If the PPDU type is other than ELR, DCM (equivalent to transmitting twice in the frequency domain) supported by 11ax and 11be can be applied. On the other hand, if the PPDU type is ELR, a repetition greater than 2 is allowed in the data frequency domain allocation, such as the above values ​​of 5 and 6. Note that the above repetition number corresponds to the repetition number for allocating data to the entire bandwidth of the PPDU BW (assumed to be 20 MHz). Note that the PPDU type may be notified, for example, in the PHY Version Identifier field.

[0120] FIG. 16 is a diagram showing an example of tones allocation when the value is 5 (52-tone + 4 repetition). In the example allocation shown in FIG. 16, the 52-tone data modulated at a coding rate of 1 / 2 is copied four times in the frequency domain and allocated to the entire PPDU BW. Furthermore, when copying, the PAPR is reduced by using different modulation mapping methods for the data. Note that the repetition data is not limited to using different modulation mapping methods. For example, repetition may be achieved by applying interleaving, which changes the order of the data. In this case, the PAPR can also be reduced. On the receiving side, the 52-tone data for four times is demodulated and combined to improve reception performance.

[0121] Furthermore, the MCS field of U-SIG-2 may be defined as follows for ELR PPDU: set to 0 for MCS 16 (BPSK 1 / 8), set to 1 for MCS 17 (BPSK 1 / 4), set to 2 for MCS 18 (QPSK 1 / 8), set to 3 for MCS 19 (QPSK 1 / 4), set to 4 for MCS 0 (BPSK 1 / 2), set to 5 for MCS 1 (QPSK 1 / 2). Values ​​6-7 are valid.

[0122] If the PPDU type is other than ELR, the lowest coding rate among the MCS patterns defined in the MCS field is 1 / 2. On the other hand, if the PPDU type is ELR, the lowest coding rate among the MCS patterns defined in the MCS field is 1 / 8.

[0123] Fig. 17 is a diagram showing an example of allocation when a coding rate of 1 / 8 is applied to BPSK. In the example shown in Fig. 13, 242 tone data coded at a coding rate of 1 / 8 and BPSK modulated is allocated to the entire PPDU BW. On the receiving side, reception performance can be improved by error correction decoding of data coded at a low rate.

[0124] In this way, by using a lower MCS rate for ELR SU PPDU data and transmitting it across the entire PPDU bandwidth than the MCS used for other PPDU types, the reception quality of the data section improves and coverage performance can be improved. Furthermore, by transmitting data across the entire PPDU BW, the maximum transmission power of the terminal can be applied even when PSD restrictions are in place. By using the tones across the entire PPDU BW, the SNR per tone decreases, but combining gain and coding gain can be obtained.

[0125] <Modifications> Modifications applicable to the above-described embodiments will now be described. When DRU is applied, the Tone start position may be changed for each AP (each BSS). For example, the Tone start position may be determined according to the BSS color (a unique value for each BSS). This allows the Tone positions to differ between BSSs, randomizing interference between BSSs and improving coverage performance.

[0126] In the above embodiment, a form using the ELR SU PPDU has been described, but it is not limited to the ELR SU PPDU, and other PPDUs (for example, TB PPDU (a response PPDU to a Trigger frame)) may also be used. For example, it may be applied to the following PPDUs: - When the PPDU including the Trigger frame is an ELR SU PPDU, the PPDU (TB PPDU) that serves as a response to that PPDU - When the notification information of the Trigger frame instructs transmission of a PPDU for the ELR, the PPDU (TB PPDU) that serves as a response to that

[0127] In the above embodiment, the BW of the ELR SU PPDU is 20 MHz, but this is not limited to 20 MHz and transmission may be performed with a BW of, for example, 320 MHz. As shown in Fig. 16 and other figures, reception quality can be improved by repeating RUs with small Tone counts multiple times in the frequency direction.

[0128] If a UHR terminal obtains a value defined as "Validate" after decoding each field of the ELR SU PPDU for UHR, it may determine that the format is unknown to the UHR terminal (for example, a format of a future standard (a standard after UHR)) and terminate the PPDU reception process.

[0129] In the above-described embodiment, the field (or subfield) used for notifying the control information is an example, and other fields or subfields may be used. Furthermore, the number of bits used for notifying the control information in each field or subfield is an example, and other numbers of bits may be used.

[0130] Furthermore, the signal format described in the above-mentioned embodiment is an example, and other configurations may be used in which at least one of other fields is added and some fields is deleted, and other configurations may be used in which at least one of other subfields is added and some subfields are deleted in each of the above-mentioned fields.

[0131] Furthermore, in the above embodiment, as an example, a case based on the format defined in IEEE 802.11 has been described, but the format to which an embodiment of the present disclosure is applied is not limited to the IEEE 802.11 format.

[0132] The present disclosure can be realized by software, hardware, or software in conjunction with hardware. Each functional block used in the description of the above embodiments may be partially or entirely realized as an LSI, which is an integrated circuit, and each process described in the above embodiments may be partially or entirely controlled by a single LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of a single chip that includes some or all of the functional blocks. The LSI may have data input and output. Depending on the degree of integration, the LSI may also be called an IC, system LSI, super LSI, or ultra LSI.

[0133] The integrated circuit method is not limited to LSI, and may be realized by a dedicated circuit, a general-purpose processor, or a dedicated processor. Also, a field programmable gate array (FPGA) that can be programmed after LSI manufacturing, or a reconfigurable processor that can reconfigure the connections and settings of circuit cells within the LSI, may be used. The present disclosure may be realized as digital processing or analog processing.

[0134] Furthermore, if an integrated circuit technology that can replace LSI emerges due to advances in semiconductor technology or other derivative technologies, it is natural that such technology may be used to integrate functional blocks. The application of biotechnology, etc. is also a possibility.

[0135] The present disclosure may be implemented in any type of apparatus, device, or system (collectively referred to as a communications apparatus) that has a communications function. The communications apparatus may include a radio transceiver and processing / control circuitry. The radio transceiver may include a receiver and a transmitter, or both functions. The radio transceiver (transmitter and receiver) may include a radio frequency (RF) module and one or more antennas. The RF module may include an amplifier, an RF modulator / demodulator, or the like. Non-limiting examples of communication devices include telephones (e.g., cell phones, smartphones), tablets, personal computers (PCs) (e.g., laptops, desktops, notebooks), cameras (e.g., digital still / video cameras), digital players (e.g., digital audio / video players), wearable devices (e.g., wearable cameras, smartwatches, tracking devices), game consoles, digital book readers, telehealth / telemedicine devices, communication-enabled vehicles or mobile transportation (e.g., cars, airplanes, ships), and combinations of the above devices.

[0136] The communication devices are not limited to portable or mobile devices, but also include any kind of non-portable or fixed equipment, devices, and systems, such as smart home devices (such as home appliances, lighting equipment, smart meters or measuring devices, control panels, etc.), vending machines, and any other "things" that may exist on an IoT (Internet of Things) network.

[0137] Communications include data communications via cellular systems, wireless LAN systems, communication satellite systems, and the like, as well as data communications via combinations of these.

[0138] A communications apparatus also includes devices such as controllers and sensors connected or coupled to a communications device that performs the communications functions described in this disclosure, such as controllers and sensors that generate control and data signals used by the communications device to perform the communications functions of the communications apparatus.

[0139] The communication apparatus also includes infrastructure facilities, such as base stations, access points, and any other apparatus, device, or system that communicates with or controls the various apparatuses listed above, but are not limited to these.

[0140] A communication device according to one embodiment of the present disclosure includes a transmission circuit that transmits an ELR (Enhanced long range) SU (Single User) PPDU (Physical layer Protocol Data Unit), and a control circuit that generates the ELR SU PPDU so that a data portion included in the ELR SU PPDU is robustly transmitted by the transmission circuit.

[0141] In one embodiment of the present disclosure, the control circuit applies a distributed-tone resource unit (DRU) to the data portion.

[0142] In one embodiment of the present disclosure, the bandwidth in which tones are allocated when the DRU is applied to the data portion is limited to a predetermined bandwidth or less.

[0143] In one embodiment of the present disclosure, the tones are equally spaced, including a direct current component (DC) tone.

[0144] In one embodiment of the present disclosure, the position at which a tone is placed when the DRU is applied to the data portion is a fixed value.

[0145] In one embodiment of the present disclosure, the control circuit applies dual carrier modulation (DCM) to the DRU.

[0146] In one embodiment of the present disclosure, the control information notified in the preamble included in the ELR SU PPDU is changed depending on whether the DRU is applied to the data section or whether an RRU (Regular Resource Unit) is applied.

[0147] In one embodiment of the present disclosure, a Modulation and Coding Scheme (MCS) using a coding rate lower than a predetermined coding rate is applied to the data portion.

[0148] In one embodiment of the present disclosure, the control circuit indicates that the PPDU is for ELR using a PHY Version Identifier field included in the ELR SU PPDU.

[0149] In a communication method according to one embodiment of the present disclosure, an Enhanced long range (ELR) Single User (SU) Physical layer Protocol Data Unit (PPDU) is generated so that a data portion included in the ELR SU PPDU is robustly transmitted by a transmitting circuit, and the generated ELR SU PPDU is transmitted.

[0150] The disclosures of the specification, drawings and abstract contained in Japanese Patent Application No. 2024-123158, filed on July 30, 2024, are incorporated herein by reference in their entirety.

[0151] One embodiment of the present disclosure is useful in wireless communication systems.

[0152] 100 Terminal 101 Control unit 102 Error correction coding unit 103 Modulation unit 104 Tone mapping unit 105 Preamble generation unit 106 STF / LTF generation unit 107 OFDM modulation unit 108, 201 Radio transmission / reception unit 200 AP 202 Preamble decoding unit 203 OFDM demodulation unit 204 Tone demapping unit 205 Demodulation unit 206 Error correction decoding unit

Claims

1. A communication device comprising: a control circuit that generates a coverage extension signal so that a data portion included in the coverage extension signal is transmitted robustly; and a transmission circuit that transmits the generated coverage extension signal.

2. The communication device according to claim 1, wherein the robust transmission applies an MCS (Modulation and Coding Scheme) using a coding rate lower than a predetermined coding rate to the data portion.

3. The communication device according to claim 1, wherein the robust transmission allocates the data portion to the frequency domain by copying the data portion for a predetermined number of repetitions.

4. The communication device according to claim 3, wherein the coverage extension signal is a coverage extension PPDU (Physical layer Protocol Data Unit), and in the robust transmission, the number of repetitions used in the data section of the coverage extension PPDU is greater than the number of repetitions used for other types of PPDU.

5. The communication device according to claim 4, wherein the number of repetitions applicable to the other type of PPDU is 2, and the number of repetitions applicable to the data portion of the coverage extension PPDU is greater than 2.

6. The communication device according to claim 5, wherein the number of repetitions used in the data section of the coverage extension PPDU is 4.

7. The communication device according to claim 3, wherein in said robust transmission, a modulation mapping method used for said data portion is made different from a modulation mapping method used for a copy of said data portion.

8. The communication device according to claim 7, wherein in said robust transmission, said data portion is modulated to 52 tones.

9. The communication device according to claim 1, wherein the coverage extension signal is a coverage extension PPDU (Physical layer Protocol Data Unit), and the control circuit indicates that the PPDU to be transmitted is a coverage extension PPDU using a PPDU type & Compression Mode field included in the PPDU to be transmitted.

10. The communication device according to claim 9, wherein the control circuit uses a PHY Version Identifier field included in the PPDU to be transmitted to indicate that the PPDU to be transmitted is a PPDU for UHR.

11. The communication device according to claim 10, wherein the PPDU includes a U-SIG-1 field and a U-SIG-2 field, the PHY Version Identifier field is included in the U-SIG-1 field, and the PPDU type & Compression Mode field is included in the U-SIG-2 field.

12. A wireless receiving device comprising: a receiving unit that receives a coverage extension signal including a robustly transmitted data portion; and a control circuit that decodes the data portion.

13. A communication method comprising: generating a coverage extension signal so that a data portion included in the coverage extension signal is transmitted robustly; and transmitting the generated coverage extension signal.

14. A communication method comprising receiving a coverage extension signal including a robustly transmitted data portion, and decoding the data portion.

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