Communication device, control method, and program

Abstract

Provided is a communication device compliant with the IEEE 802.11 standard series, the communication device having a transmission means for, by using a first data subcarrier and a second data subcarrier belonging to a first group and a second group, respectively, obtained by dividing, into two groups, a data subcarrier included in one resource unit in which subcarriers are distributed in a distributed bandwidth, modulating and transmitting the same data.

Description

Communication device, control method, and program 【0001】 This disclosure relates to a communication device, a control method, and a program. 【0002】 With the recent increase in the amount of data transmitted, the development of communication technologies such as wireless LAN (Local Area Network) is progressing. The IEEE (Institute of Electrical and Electronics Engineers) 802.11 standard series is known as the main communication standard for wireless LAN. The IEEE 802.11 standard series includes standards such as IEEE 802.11a / b / g / n / ac / ax / be. To further improve the reliability of communication, the IEEE 802.11bn standard is being developed as the successor to the IEEE 802.11be standard. The IEEE 802.11WG (Working Group), which is developing the IEEE 802.11bn standard, will define the objectives and scope of the standard in the UHR SG, and specify the detailed technical content to be included in the standard in TGbn. UHR SG is an abbreviation for Ultra High Reliability Study Group, and TGbn is an abbreviation for Task Group bn. The name UHR was created for convenience, taking into account the objectives to be achieved in the successor standard and the key features of the standard, and may be renamed once the standard is finalized. Similarly, the name IEEE 802.11bn may be renamed once the standard is finalized. On the other hand, this specification and the attached claims are essentially applicable to all successor standards that are successors to the 802.11be standard. 【0003】 Patent Document 1 discloses communication using OFDMA (Orthogonal Frequency Division Multiple Access) (also called OFDMA communication). In OFDMA communication, an access point (AP) allocates a frequency domain (subchannel) to a station (STA) on a resource unit (RU) basis. 【0004】 Here, RU is a division unit of the channel used for communication, and an RU includes a plurality of subcarriers (also called sub-carriers or tones). For channels with frequency bandwidths of 20 MHz, 40 MHz, 80 MHz, 160 MHz, and 320 MHz respectively, the method of division into RUs (the size and range of the RUs) is defined. When the plurality of subcarriers constituting one RU are continuous in the frequency domain, the RU is also referred to as a Regular RU (RRU). 【0005】 Patent Document 2 discloses a communication method using a Distributed tone Resource Unit (DRU) that uses subcarriers distributed as subcarriers constituting a single RU. DRU is an abbreviation of Distributed tone Resource Unit (distributed tone resource unit or distributed resource unit). In this specification and the drawings, DRU is also described as dRU. 【0006】 The RRU is composed of continuous subcarriers. In contrast, the DRU is composed of subcarriers distributed over a wide frequency band. Thereby, the transmission power density can be reduced, so that it is possible to increase the transmission power even in the 6 GHz band where legal regulations on the transmission power density are strict. 【0007】 Japanese Unexamined Patent Application Publication No. 2023 - 47755, Japanese Patent Publication No. 2024 - 516188 【0008】 By the way, in the IEEE802.11ax standard and the IEEE802.11be standard, Dual Carrier Modulation (DCM) is adopted. DCM is a technique for transmitting the same data using two subcarriers. Thereby, it is possible to reduce the data error rate by the diversity effect of combining and decoding on the receiving side. 【0009】 However, the mechanism for applying DCM to DRU has not been established and is not clear. Therefore, unless such a mechanism is clarified, it is not possible to provide advantages such as reduction of the data error rate and extension of the communication distance obtained by the combination of DRU and DCM. 【0010】One aspect of this disclosure, in view of the above, aims to provide a technology for appropriately applying DCM to DRU. 【0011】 A communication device according to one aspect of the present disclosure is a communication device compliant with the IEEE 802.11 standard series, and includes a transmitting means that modulates and transmits the same data using one first data subcarrier and one second data subcarrier belonging to a first group and a second group, respectively, obtained by dividing a data subcarrier contained in a single resource unit in which subcarriers are distributed across a distributed bandwidth into two groups. 【0012】 According to one aspect of this disclosure, DCM can be appropriately applied to DRU. 【0013】 A diagram showing an example configuration of a wireless communication system according to an embodiment. A diagram showing an example of the functional configuration of a communication device according to an embodiment. A diagram showing an example of the functional configuration of a communication device according to an embodiment. A diagram showing an example of the hardware configuration of a communication device according to an embodiment. A diagram showing the concepts of DRU and distributed bandwidth. A diagram showing the concept of PPDU with a bandwidth of 160 MHz. A diagram showing an example of a set of subcarriers modulated based on the same data according to an embodiment. A diagram showing an example of a DRU constituting a 20 MHz distributed bandwidth and a subcarrier constituting each DRU according to an embodiment. A diagram showing an example of a DRU constituting a 40 MHz distributed bandwidth and a subcarrier constituting each DRU according to an embodiment. A diagram showing an example of a DRU constituting an 80 MHz distributed bandwidth and a subcarrier constituting each DRU according to an embodiment. 【0014】 The embodiments will be described in detail below with reference to the attached drawings. Note that the following embodiments do not limit the scope of the claims. While the embodiments describe multiple features, not all of these features are essential to this disclosure, and the features may be combined in any way. Furthermore, in the attached drawings, identical or similar configurations are given the same reference numerals, and redundant descriptions are omitted. 【0015】<Embodiment> (Network Configuration) Figure 1 is a diagram showing an example configuration of a wireless communication system according to this embodiment. Figure 1 shows an example of a network configuration related to this embodiment. Figure 1 shows a configuration including one AP (Access Point) 102 and three STAs (Stations) 103, 104, and 105 as a (wireless) communication device that performs wireless LAN communication compliant with the IEEE 802.11bn standard. STAs are sometimes called non-AP STAs. 【0016】 As shown in Figure 1, the network formed by AP 102 is indicated by circle 101. STA 103-105 can transmit and receive signals transmitted and received by AP 102. In this embodiment, AP 102 and STA 103-105 are sometimes collectively referred to as the communication device 100. Note that the configuration shown in Figure 1 is just one example, and other communication devices performing wireless LAN communication may exist in a wider area, for example. 【0017】 The communication device 100 may be a communication device that performs wireless LAN communication compliant with the IEEE 802.11bn standard. Alternatively, the communication device 100 may be a so-called legacy device that does not comply with the IEEE 802.11bn standard but only with the IEEE 802.11a / b / g / n / ac / ax / be standards. 【0018】 The communication device 100 can also be configured to support wireless communication based on other communication standards such as Bluetooth®, NFC, and Bluetooth LE (Low Energy). NFC is an abbreviation for Near Field Communication. 【0019】 Furthermore, the communication device 100 can also be configured to support wired communication using Ethernet® cables or wired communication using optical fibers. 【0020】 Furthermore, the communication device 100 can also be configured to support cellular wireless communication such as 5G and LTE (Long Term Evolution). 【0021】Specific examples of AP102 include, but are not limited to, wireless LAN routers and personal computers (PCs). 【0022】 Specific examples of STA103-105 include, but are not limited to, cameras, tablets, smartphones, PCs, mobile phones, video cameras, smart glasses, and wearable devices such as HMDs (head-mounted displays). Furthermore, STA103-105 may also be IoT devices such as Internet of Things (IoT) sensors, smart locks, and smart sensors. IoT sensors may include accelerometers, light sensors, humidity sensors, etc. 【0023】 Furthermore, the communication device 100 may be an information processing device such as a wireless chip capable of performing wireless communication in accordance with IEEE 802.11 standards such as the IEEE 802.11bn standard. Alternatively, the communication device 100 may be an information processing device such as a wireless chip that supports the transmission and reception of Physical Layer Protocol Data Units (PPDUs). In this case, it can be configured to perform various controls by hardware circuits inside the wireless chip. It can also be configured so that various processes are performed by the cooperation of a processor such as an ASIP, memory, and hardware circuits inside the wireless chip. ASIP is an abbreviation for Application-Specific Instruction set Processor. 【0024】 (Configuration of AP and STA) Figures 2A and 2B are block diagrams showing examples of the functional configurations of AP102 and STA103-105. 【0025】 As an example of its functional configuration, AP102 has a RU assignment unit 201, a frame generation and analysis unit 202, and a frame transmission and reception unit 203, as shown in Figure 2A. On the other hand, as an example of its functional configuration, STA103-105 has a frame generation and analysis unit 202 and a frame transmission and reception unit 203, as shown in Figure 2B. In other words, the RU assignment unit 201 is present only in AP102 and not in STA103-105. 【0026】These functions can be realized, for example, by the control unit 302 (described later) executing a program stored in the storage unit 301 (described later), or by the processing function unit in the communication unit 306 (described later). Figures 2A and 2B illustrate the main functions in this embodiment, and other functions are omitted. For this reason, AP 102 and STA 103-105 may naturally have functions for establishing a connection between AP and STA and control for communication, as well as functions that communication devices generally have. In addition, the multiple function blocks shown in Figures 2A and 2B may be integrated into one function block, or one function block may be divided into multiple function blocks. Furthermore, the names of the function blocks shown in Figures 2A and 2B are merely examples and may be changed. 【0027】 The RU allocation unit 201 determines the multiple access method to be used for communication with STA 103-105. The multiple access method includes OFDMA. If the RU allocation unit 201 determines that OFDMA should be used, it determines whether to use RRU or DRU and allocates either RRU or DRU to STA 103-105. The RU allocation unit 201 makes these decisions based on the number of STAs connected to AP 102, the traffic between one or more connected STAs, the frequency band being used, the distance to the STAs, etc. For example, the RU allocation unit 201 determines that OFDMA should be used if the number of STAs is large (e.g., more than a predetermined number) and the traffic between each STA is small (e.g., less than or equal to a predetermined value). Furthermore, the RU allocation unit 201 determines that DRU should be used if the 6GHz band is being used or if the distance to the STAs is long (e.g., more than a predetermined value). 【0028】 Furthermore, the RU allocation unit 201 may decide to apply DCM if the STA's communication environment is poor. A poor STA communication environment is, for example, when the STA's communication quality is below a threshold. The STA's communication quality may be represented by at least one of the following parameters: communication distance, interference amount, SNR (Signal-to-Noise Ratio), error rate, etc. 【0029】The frame generation and analysis unit 202 generates frames to be output to the frame transmission / reception unit 203 according to the multiple access scheme determined by the RU assignment unit 201, and analyzes the frames input from the frame transmission / reception unit 203. 【0030】 The frame transmission / reception unit 203 encodes the frame input from the frame generation / analysis unit 202 according to the multiple access scheme determined by the RU assignment unit 201, modulates the encoded frame, and transmits the modulated frame as radio waves to the wireless medium. The frame transmission / reception unit 203 also demodulates the radio waves (including frame information) received from the wireless medium, decodes the received frame, and outputs the decoded frame to the frame generation / analysis unit 202. The frame transmission / reception unit 203 is an example of a transmission means, receiving means, transmission / reception means, or communication means. 【0031】 Figure 3 shows an example of the hardware configuration of AP102 and STA103-105 (communication device 100). 【0032】 AP102 and STA103-105, as an example of their hardware configuration, include 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 a wireless antenna 307. 【0033】 The storage unit 301 is composed of one or more memories, such as both ROM and RAM, or either one of them, and stores various information such as programs for performing various operations described later, and communication parameters (setting information) for wireless communication. In addition to memories such as ROM and RAM, storage media such as flexible disks, hard disks, SSDs, optical disks, magneto-optical disks, CD-ROMs, CD-Rs, magnetic tapes, non-volatile memory cards, and DVDs may be used as the storage unit 301. SSD is an abbreviation for Solid State Drive. CD-ROM is an abbreviation for Compact Disc Read Only Memory, CD-R is an abbreviation for Compact Disc Recordable, and DVD is an abbreviation for Digital Versatile Disc. 【0034】The control unit 302 is composed of, for example, one or more processors such as a CPU and MPU, an ASIC (Application-Specific Integrated Circuit), a DSP (Digital Signal Processor), an FPGA (Field-Programmable Gate Array), etc. CPU is an abbreviation for Central Processing Unit, and MPU is an abbreviation for Micro Processing Unit. The control unit 302 controls the entire device by executing a program stored in the storage unit 301. Alternatively, the control unit 302 may control the device in cooperation with the OS (Operating System) and the program stored in the storage unit 301. 【0035】 Furthermore, the control unit 302 controls the functional unit 303 to perform predetermined processes such as imaging, printing, and projection. The functional unit 303 is hardware for the AP or STA to perform predetermined processes. For example, if the AP or STA is a camera, the functional unit 303 is the imaging unit and performs imaging processing. Also, for example, if the AP or STA is a printer, the functional unit 303 is the printing unit and performs printing processing. Also, for example, if the AP or STA is a projector, the functional unit 303 is the projection unit and performs projection processing. The data processed by the functional unit 303 may be data stored in the storage unit 301, or data communicated with other communication devices via the communication unit 306, which will be described later. 【0036】 The input unit 304 accepts various operations from the user. The output unit 305 provides various outputs to the user. Here, the output from the output unit 305 includes at least one of the following: display on the screen, audio output from a speaker, vibration output, etc. Note that both the input unit 304 and the output unit 305 may be implemented in a single module, such as a touch panel. Furthermore, the input unit 304 and the output unit 305 may be integrated with the AP or STA, respectively, or they may be separate components. 【0037】The communication unit 306 includes a so-called wireless LAN chip and performs control of wireless communication compliant with the IEEE 802.11 standard series, control of IP (Internet Protocol) communication, etc. In this embodiment, the communication unit 306 can perform processing compliant with at least the IEEE 802.11bn standard. The communication unit 306 is a processing device that generates UHR PPDU (Ultra High Reliability Physical Layer Protocol Data Unit) as defined in the IEEE 802.11bn standard. The communication unit 306 may also have the function of generating types of PPDUs defined in standards prior to the IEEE 802.11bn standard. Furthermore, the communication unit 306 controls the wireless antenna 307 to transmit and receive wireless signals for wireless communication. The communication device 100 communicates content such as image data, document data, and video data with other communication devices via the communication unit 306. 【0038】 The wireless antenna 307 may be physically composed of two or more antennas in order to realize MIMO (Multi-Input and Multi-Output) transmission and reception. The wireless antenna 307 may be configured separately from the communication unit 306, or it may be configured as a single module together with the communication unit 306. The wireless antenna 307 is an antenna capable of communication in the 2.4 GHz band, 5 GHz band, 6 GHz band, 45 GHz band, and 60 GHz band. In Figure 3, the communication device 100 is shown to have one antenna, but it may have two or more antennas. Alternatively, the communication device 100 may have different antennas for each frequency band. 【0039】 In the example shown in Figure 3, the communication device 100 is configured to have only one communication unit 306, but it is also possible to provide a separate communication unit for each of the multiple wireless antennas. 【0040】 Furthermore, AP102 and STA103-105 may be any communication device having the configurations shown in Figures 2A, 2B, and 3, and are not limited to the examples of equipment mentioned above. 【0041】(Concepts of DRU and Distributed Bandwidth) Next, the concepts of DRU and distributed bandwidth will be described using FIG. 4. 【0042】 In FIG. 4, the bandwidth 400 of the PPDU is shown. The bandwidth of the bandwidth 400 of the PPDU can be 20 MHz, 40 MHz, 80 MHz, 160 MHz, or 320 MHz. 【0043】 In FIG. 4, the distributed bandwidths 401 - 403 are also shown. The bandwidth of each of the distributed bandwidths 401 - 403 can be 20 MHz, 40 MHz, or 80 MHz. Alternatively, the bandwidth of the distributed bandwidths 401 - 403 is not limited to the above-mentioned values and may be an integer multiple or one over an integer of 20 MHz. The bandwidths of the distributed bandwidths 401 - 403 may all be the same, some may be different, or all may be different. 【0044】 The bandwidth of one PPDU may include one or more distributed bandwidths. FIG. 4 shows an example where the bandwidth 400 of one PPDU includes three distributed bandwidths 401 - 403. When the bandwidth of one PPDU includes only one distributed bandwidth, the bandwidth of the PPDU and the bandwidth of the distributed bandwidth may coincide. 【0045】 In FIG. 4, for example, when the bandwidth of the bandwidth 400 of the PPDU is 80 MHz, the bandwidths of the distributed bandwidth 401, the distributed bandwidth 402, and the distributed bandwidth 403 can be 20 MHz, 20 MHz, and 40 MHz, respectively. 【0046】 One distributed bandwidth may include one or more DRUs. In the case of the distributed bandwidth 401, the distributed bandwidth 401 includes four DRUs, DRU1 - DRU4. The subcarriers constituting each DRU are arranged discontinuously across the entire distributed bandwidth 401. That is, from the lower frequency to the higher frequency, the subcarriers of DRU1, the subcarriers of DRU2, the subcarriers of DRU3, and the subcarriers of DRU4 are repeatedly arranged. The subcarriers constituting the DRU may include data subcarriers and pilot subcarriers. 【0047】Each dispersed band may include unused subcarriers that do not belong to any DRU. The unused subcarriers may include guard subcarriers, DC (Direct Current) subcarriers, etc. The unused subcarriers may exist between the subcarriers that constitute the DRU. 【0048】 Similar to the dispersed band 401, the dispersed band 402 and the dispersed band 403 may also include one or more DRUs. 【0049】 Each dispersed band may include one or more RRUs. The RRU is a RU first defined in IEEE 802.11ax. The subcarriers that constitute the RRU are arranged continuously on the frequency axis. The subcarriers that constitute the RRU may include data subcarriers and pilot subcarriers. Even if the dispersed band includes an RRU, the dispersed band may include unused subcarriers that do not belong to any RRU. The unused subcarriers may include guard subcarriers, DC subcarriers, etc. The unused subcarriers may exist between the subcarriers that constitute the RRU. 【0050】 Note that a DRU and an RRU do not coexist in one dispersed band. Also, in the dispersed band including an RRU, the subcarriers that constitute the RU are not arranged dispersedly. Therefore, the dispersed band including an RRU may be called by another name such as a partial band, a normal band, etc. 【0051】 (Concept of PPDU with a bandwidth of 160 MHz) When the bandwidth of the band of the PPDU is 160 MHz or 320 MHz, the relationship between the band, the dispersed bands that can be arranged in the band, and further the DRUs that can be arranged in the dispersed bands may be a repetition on the frequency axis of the relationship regarding the 80 MHz band. 【0052】Figure 5 shows a conceptual diagram of a PPDU with a bandwidth of 160 MHz. In Figure 5, the PPDU bandwidth 500 is shown. As shown in Figure 5, the bandwidth of the PPDU bandwidth 500 is 160 MHz. In Figure 5, bandwidths 501 and 502, which have a bandwidth of 80 MHz, are also shown. As shown in Figure 5, when the PPDU bandwidth is 160 MHz, the 80 MHz bandwidth is repeated twice on the frequency axis. If the PPDU bandwidth is 320 MHz, the 80 MHz bandwidth will be repeated four times on the frequency axis. 【0053】 (Example of a set of subcarriers modulated based on the same data) Next, a method for constructing a set of subcarriers modulated based on the same data, that is, a set of subcarriers to which Dual Carrier Modulation (DCM) is applied, will be explained using Figure 6. 【0054】 Figure 6 shows an example of a set of subcarriers modulated based on the same data. In Figure 6, an exemplary dispersed bandwidth 401 is shown. 【0055】 A subcarrier pair is composed of two data subcarriers, obtained by dividing a single dispersed bandwidth data subcarrier into two groups: a high-frequency group and a low-frequency group, and selecting one data subcarrier from each group. For example, if one subcarrier is the i-th data subcarrier from the lower frequencies that make up the DRU, then the other subcarrier will be the i + (number of data subcarriers making up the DRU / 2)-th data subcarrier from the lower frequencies. i is a natural number less than (number of data subcarriers / 2) + 1. By composing a subcarrier pair with subcarriers that are far apart in frequency, resistance to frequency-selective fading can be strengthened. 【0056】 Figures 7, 8, and 9 show examples of DRUs that constitute the 20 MHz, 40 MHz, and 80 MHz dispersion bands, respectively, and the subcarriers that make up each DRU. 【0057】The configuration of the DRU is defined for each dispersion band. Each DRU is assigned an index. In each DRU, the arrangement of subcarriers is indicated using the subcarrier index. The subcarrier index is a sequence of integers assigned to the subcarriers included in the dispersion band, starting from the lowest frequency subcarrier. For example, the indices are assigned as follows: for the 20 MHz bandwidth, indices -121 to 121 are assigned; for the 40 MHz bandwidth, indices -244 to 244 are assigned; for the 80 MHz bandwidth, indices -500 to 500 are assigned; and for the 160 MHz bandwidth, indices -1012 to 1012 are assigned. 【0058】 Like RRUs, DRUs are composed of multiple subcarriers, and the number of subcarriers constituting a DRU is the same as that of an RRU. That is, DRU patterns include 26-tone DRUs, 52-tone DRUs, 106-tone DRUs, 242-tone DRUs, and 484-tone DRUs. The number of subcarriers in the 26-tone DRUs, 52-tone DRUs, 106-tone DRUs, 242-tone DRUs, and 484-tone DRUs are 26, 52, 106, 242, and 484, respectively. 【0059】 The [S1, S2, ...] shown in Figures 5 to 7 represent that the DRU is composed of subcarriers of a set of indices corresponding to S1, S2, ... Each of S1 and S2 represents an index of a single subcarrier, a set of indices of multiple subcarriers, or a set of indices that constitute the DRU. Furthermore, the [s1:d:s2] shown in Figures 5 to 7 represents the set of indices of index s1, all indices that satisfy index s1+d (where d is a natural number and s1+d < s2), and the set of indices of index s2. 【0060】For example, in the case of a 26-tone DRU7 [-120:9:-12,6:9:114] in a 20MHz bandwidth as shown in Figure 7, this DRU is composed of 26 subcarriers. The 26 subcarriers can be represented by the following subcarrier indices: -120, -111, -102, -93, -84, -75, -66, -57, -48, -39, -30, -21, -12, 6, 15, 24, 33, 42, 51, 60, 69, 78, 87, 96, 105, 114. In this case, the sets of subcarriers to which DCM is applied are, for example, (-120 and 6), (-111 and 15), ..., (-12 and 114). 【0061】 Furthermore, the 52-tone DRU and 106-tone DRU shown in Figure 7 are based on a combination of 26-tone DRUs. For example, the 52-tone DRU3 in a 20MHz bandwidth consists of 26-tone DRU7 and 26-tone DRU8. In this case, the DRU is composed of 52 subcarriers. The 52 subcarriers, when represented by subcarrier indices, include the following: -120, -116, -111, -107, -102, -98, -93, -89, -84, -80, -75, -71, -66, -62, -57, -53, -48, -44, -39, -35, -30, -26, -21, -17, -12, -8. The 52 subcarriers, when expressed by subcarrier index, further include the following: 6, 10, 15, 19, 24, 28, 33, 37, 42, 46, 51, 55, 60, 64, 69, 73, 78, 82, 87, 91, 96, 100, 105, 109, 114, 118. In this case, the sets of subcarriers to which DCM is applied are, for example, (-120 and 6), (-116 and 10), ..., (-12 and 114), (-8 and 118). 【0062】In this embodiment, the DRU is configured such that the same number of subcarriers as the RRU are regularly arranged across the entire bandwidth. However, the number and arrangement of subcarriers constituting the DRU are not limited to this. For example, the DRU may consist of fewer or more subcarriers than the RRU, or the subcarriers may be arranged irregularly. However, it is necessary to distribute the subcarriers across the entire communication bandwidth and reduce the power density compared to conventional RRUs. 【0063】 Furthermore, the bandwidths for communication using DRUs are 20 MHz, 40 MHz, and 80 MHz, and the supported DRU sizes for each of these bandwidths are as follows: For the 20 MHz bandwidth, the supported DRU sizes are 26-tone DRU, 52-tone DRU, and 106-tone DRU. For the 40 MHz bandwidth, the supported DRU sizes are 26-tone DRU, 52-tone DRU, 106-tone DRU, and 242-tone DRU. For the 80 MHz bandwidth, the supported DRU sizes are 52-tone DRU, 106-tone DRU, 242-tone DRU, and 484-tone DRU. 【0064】 However, this disclosure is not limited to the foregoing, and a 26-tone DRU may be used in an 80 MHz bandwidth, or communication using a DRU may be performed in a 160 MHz bandwidth. When a 26-tone DRU is used in an 80 MHz bandwidth, the 26-tone DRU can be newly allocated to 37 STAs, so DRU1 to DRU70 will be used as DRU indexes. 【0065】Furthermore, the subcarrier to which DCM is applied is modulated with BPSK and coded with BCC or LDPC at a coding rate of 1 / 2. BPSK is an abbreviation for Binary Phase Shift Keying, BCC is an abbreviation for Binary Convolutional Code, and LDPC is an abbreviation for Low Density Party Check. This makes it possible to provide a combination of modulation and coding schemes that is more noise-resistant than any data rate or MCS that does not apply DCM in the IEEE 802.11 standard series. MCS is an abbreviation for Modulation and Coding Scheme. 【0066】 However, other primary modulation schemes and encoding schemes may be applied in DCM. For example, any of MCS0 to 4 may be applied. Alternatively, any of MCS0, 1, 3, and 4 may be applied. Furthermore, for example, a modulation scheme with a modulation level of less than or equal to a predetermined value and an encoding scheme with a coding rate of less than or equal to a predetermined value may be applied. Specifically, modulation schemes and encoding schemes such as QPSK with a coding rate of 1 / 2, 16QAM with a coding rate of 1 / 2, and 16QAM with a coding rate of 3 / 4 may be applied. QPSK is an abbreviation for Quadrature Phase Shift Keying, and QAM is an abbreviation for Quadrature Amplitude Modulation. This allows for a more flexible selection of combinations of modulation schemes and encoding schemes according to the required data rate, the noise environment of the transmission line, etc. 【0067】 Furthermore, the number of spatial streams may be limited in DCM. For example, the number of spatial streams may be set to 1 or 2. Also, DCM and STBC (Space-Time Block Coding) do not necessarily have to be applied in combination. 【0068】According to the embodiment described above, on the transmitting side, the data subcarrier contained in a single RU (i.e., DRU) in which subcarriers are distributed across a distributed bandwidth is divided into two groups: a first group and a second group. The same data is then modulated and transmitted using one first data subcarrier and one second data subcarrier belonging to each of the first and second groups obtained by this division. On the receiving side, the same data that has been modulated and transmitted using the first and second data subcarriers in this manner is received and demodulated. This makes it possible to apply DCM to the DRU, and it becomes possible to achieve a reduction in data error rate, an increase in communication distance, etc., which can be obtained by combining DRU and DCM. 【0069】 <Other Embodiments> In the above embodiment, an example was described in which the data subcarriers constituting one dispersion band are divided into two groups, consisting of a high-frequency group and a low-frequency group, and one data subcarrier is selected from each group to form a set of subcarriers. However, the disclosure is not limited to this example. For example, the data subcarriers constituting one dispersion band may be divided into a group with an odd subcarrier index and a group with an even subcarrier index, and one data subcarrier is selected from each group to form a set of subcarriers. 【0070】 In the above embodiment, an example was described in which the set of subcarriers to which DCM is applied is provided as one pattern for each DRU. However, the disclosure is not limited to this example. For example, multiple patterns of data subcarrier sets to which DCM is applied may be provided for DRUs consisting of the same subcarriers in the same bandwidth. The AP may also notify the STA of the pattern by deciding which of the multiple patterns to use and transmitting information about the decided pattern to the STA. 【0071】The above embodiment describes an example in which two groups obtained by splitting the DRU are predetermined. However, the disclosure is not limited to this example. For example, the AP may adaptively or dynamically determine the two groups after splitting, and may notify the STA of the two groups by storing information about the two determined groups in a field (new or existing) related to resource allocation and sending it. 【0072】 The above embodiment describes an example in which the same data is modulated and transmitted using one subcarrier selected from each of two groups obtained by dividing the DRU. However, this disclosure is not limited to this example. For example, the same data may be modulated and transmitted using one subcarrier selected from each of three or more groups obtained by dividing the DRU. The three or more groups may be predetermined, or determined adaptively or dynamically. In addition, the set of data subcarriers when divided into two groups, the set of data subcarriers when divided into three groups, etc., may be predetermined. In this case, the AP may decide how many groups to use according to the communication quality of the STA, etc., and notify the STA of how many groups to use by transmitting information about the determined number of groups. 【0073】 A storage medium containing program code for software that implements the above-described functions may be supplied to a system or device, and the computer (CPU, MPU) of the system or device may read and execute the program code stored on the storage medium. In this case, the program code read from the storage medium itself implements the functions of the above-described embodiment, and the storage medium containing that program code constitutes the above-described device. 【0074】 For supplying program code, storage media such as flexible disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, CD-Rs, magnetic tapes, non-volatile memory cards, ROMs, DVDs, etc., can be used. 【0075】Furthermore, the above-mentioned functions may be realized not only by the computer executing the program code it reads, but also by the operating system running on the computer performing some or all of the actual processing based on the instructions of that program code. 【0076】 Furthermore, the program code read from the storage medium is written to the memory of a function expansion board inserted into the computer or a function expansion unit connected to the computer. Then, based on the instructions of that program code, the CPU of the function expansion board or function expansion unit may perform some or all of the actual processing to realize the above-mentioned functions. 【0077】 This disclosure can also be implemented by supplying a program that implements one or more of the functions of the embodiments described above to a system or device via a network or storage medium, and by having one or more processors in the computer of that system or device read and execute the program. Furthermore, this disclosure can also be implemented by a circuit (e.g., ASIC) that implements one or more functions. 【0078】 Furthermore, some of the processes described in this disclosure with reference to the flowchart may be implemented in hardware. For example, a dedicated circuit can be automatically generated on the FPGA from a program to implement each step by using a predetermined compiler. Alternatively, a Gate Array circuit may be formed in the same way as the FPGA and implemented in hardware. 【0079】 The names of the functional units, messages, parameters, fields, etc., described in the embodiments described above may be changed to other names. 【0080】 The order of the processing procedures, sequences, flowcharts, etc., in the embodiments described above is not limited to the specific order presented, and may be rearranged or additional steps may be added, as long as they do not contradict each other. 【0081】 The present invention is not limited to the embodiments described above, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, the following claims are attached to make the scope of the invention public. 【0082】 This application claims priority based on Japanese Patent Application No. 2024-218385, filed on December 13, 2024, and all of its contents are incorporated herein by reference. 【0083】 102 Communication device (AP) 103, 104, 105 Communication device (STA)

Claims

1. A communication device compliant with the IEEE 802.11 standard series, comprising a transmitting means for modulating and transmitting the same data using one first data subcarrier and one second data subcarrier belonging to a first group and a second group, respectively, obtained by dividing a data subcarrier contained in a single resource unit in which subcarriers are distributed across a distributed bandwidth into two groups.

2. The communication device according to claim 1, wherein the frequency of the subcarrier constituting the second group is higher than the frequency of any of the subcarriers constituting the first group.

3. The communication device according to claim 1 or 2, wherein the first data subcarrier and the second data subcarrier are, respectively, the i-th data subcarrier (where i is a natural number less than (number of data subcarriers / 2) + 1) and the i + (number of data subcarriers / 2)-th data subcarrier, counting from the lowest frequency of the data subcarriers.

4. The communication device according to any one of claims 1 to 3, wherein the same data is modulated using a predetermined modulation scheme.

5. The communication device according to claim 4, wherein the predetermined modulation scheme is the BPSK (Binary Phase Shift Keying) scheme.

6. The communication device according to claim 4 or 5, wherein the same data is encoded at a predetermined coding rate.

7. The communication device according to claim 6, wherein the predetermined coding rate is 1 / 2.

8. The communication device according to claim 7, wherein the same data is encoded using BCC (Binary Convolutional Code) or LDPC (Low Density Partity Check).

9. A communication device conforming to the IEEE 802.11 standard series, comprising a receiving means for receiving and modulating the same data that has been modulated and transmitted using one first data subcarrier and one second data subcarrier belonging to each of a first and second group, obtained by dividing a data subcarrier contained in a single resource unit in which subcarriers are distributed across a distributed bandwidth into two groups.

10. The communication device according to claim 9, wherein the frequency of the subcarrier constituting the second group is higher than the frequency of any of the subcarriers constituting the first group.

11. The communication device according to claim 9 or 10, wherein the first data subcarrier and the second data subcarrier are, respectively, the i-th data subcarrier (where i is a natural number less than (number of data subcarriers / 2) + 1) and the i + (number of data subcarriers / 2)-th data subcarrier, counting from the lowest frequency of the data subcarriers.

12. The communication device according to any one of claims 9 to 11, wherein the same data is modulated using a predetermined modulation scheme.

13. The communication device according to claim 12, wherein the predetermined modulation scheme is the BPSK (Binary Phase Shift Keying) scheme.

14. The communication device according to claim 12 or 13, wherein the same data is encoded at a predetermined coding rate.

15. The communication device according to claim 14, wherein the predetermined coding rate is 1 / 2.

16. The communication device according to claim 15, wherein the same data is encoded using BCC (Binary Convolutional Code) or LDPC (Low Density Partity Check).

17. A control method for a communication device conforming to the IEEE 802.11 standard series, comprising the step of modulating and transmitting the same data using a first data subcarrier and a second data subcarrier, each belonging to a first group and a second group, obtained by dividing a data subcarrier contained in a single resource unit in which subcarriers are distributed across a distributed bandwidth into two groups.

18. A control method for a communication device conforming to the IEEE 802.11 standard series, comprising the step of receiving and demodulating the same data that has been modulated and transmitted using one first data subcarrier and one second data subcarrier each belonging to a first group and a second group, respectively, obtained by dividing a data subcarrier contained in a single resource unit in which subcarriers are distributed across a distributed bandwidth into two groups.

19. A program for causing a computer to execute the control method described in claim 17 or 18.

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