Communication device, communication method, and program

Abstract

To provide a communication technique that can increase the number of communication devices to be accommodated.SOLUTION: A communication device comprises: means that maps transmission data to an N-dimensional first vector; means that converts a first vector into a second vector by multiplying the first vector by a first regular matrix in a size N; processing means that generates, on the basis of the second vector, M-dimensional (M≥N) third vectors corresponding to N times according to element information, in which the value of an element corresponding to the n-th time (n is an integer from 1 to N) of the third vector corresponding to the n-th time is the same as the value of an element corresponding to the n-th time of the second vector, and the value of the other elements is 0; means that converts the third vector corresponding to the N-th time into a fourth vector corresponding to the n-th time by multiplying the third vector by a second regular matrix; and transmission means that transmits M numerical value sequences indicated by the fourth vector corresponding to the n-th time from the n-th time.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to communications technology. [Background technology]

[0002] IoT (Internet of Things) devices, which are wireless devices (WDs) used in smart meters and the like, communicate with server devices and the like located in a communication network via access points (APs). An AP is a communication device that accommodates one or more WDs and provides the WDs with wireless access to the communication network, and is also called a base station (BS). Non-Patent Document 1 discloses a communication technology called LoRa that is used in wireless communication between IoT devices and APs that accommodate the IoT devices. [Prior art documents] [Non-patent literature]

[0003] [Non-Patent Document 1] SEMTECH,"AN1200.22 LoRaTM Modulation Basics", May 2015 Summary of the Invention [Problem to be solved by the invention]

[0004] In the communication technology disclosed in Non-Patent Document 1, as the number of IoT devices communicating with an AP increases, the number of packets that the AP can successfully receive is limited due to the effects of interference, etc. For example, if one AP communicates with 500 IoT devices and each IoT device sends 1,500 packets per hour, the number of packets that the AP can successfully receive is approximately 200 packets per IoT device. For this reason, in the communication technology disclosed in Non-Patent Document 1, the number of IoT devices that can be accommodated in an AP (accommodation capacity) is limited.

[0005] The present disclosure provides a communication technology that can increase the number of communication devices that can be accommodated. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, a communication device includes: storage means for storing processing information including time information indicating N times from a first time to an Nth time; frequency information indicating a frequency at each of the N times indicated by the time information; a one-to-one correspondence between the N times indicated by the time information and N elements of an N-dimensional vector; and element information indicating a one-to-one correspondence between the N times indicated by the time information and N elements of an M-dimensional vector, where N is an integer equal to or greater than 2 and M is an integer equal to or greater than N; mapping means for mapping transmission data to an N-dimensional first vector; first conversion means for converting the first vector into an N-dimensional second vector by multiplying the first vector by a first regular matrix of size N; and conversion means for converting the first vector into an N-dimensional second vector according to the element information. the processing means performing a process of generating an M-dimensional third vector corresponding to an n-th time (n is an integer from 1 to N) based on the second vector, wherein a value of an element of the third vector corresponding to the n-th time is the same as a value of an element of the second vector corresponding to the n-th time, and a value of an element of the third vector corresponding to the n-th time that is different from the element corresponding to the n-th time is 0; second conversion means converting the third vector corresponding to the n-th time into an M-dimensional fourth vector corresponding to the n-th time by multiplying the third vector corresponding to the n-th time by a second regular matrix of size M; and transmission means transmitting, from the n-th time, M numerical sequences indicated by the fourth vector corresponding to the n-th time using a signal of a frequency at the n-th time indicated by the frequency information. [Effects of the Invention]

[0007] According to the present disclosure, the number of communication devices that can be accommodated can be increased. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a configuration diagram of a wireless communication system used to explain an embodiment. [Figure 2] FIG. 2 is a diagram showing an example of the configuration of a WD and an AP. [Figure 3] FIG. 10 is a diagram showing an example of mapping information. [Figure 4] FIG. 10 is a diagram showing an example of processing information. [Figure 5] FIG. 10 is a diagram showing an example of a signal transmitted by each WD. [Figure 6] FIG. 10 is an explanatory diagram of downstream communication. [Figure 7] FIG. 1 is a diagram showing an example of a cluster configuration. [Figure 8] FIG. 10 is a diagram showing an example of mapping information. [Figure 9] FIG. 10 is a diagram showing an example of mapping information. [Figure 10] FIG. 10 is a diagram showing an example of conversion information. [Figure 11] FIG. 10 is a diagram showing an example of processing information taking conversion information into consideration. [Figure 12] FIG. 10 is a diagram showing an example of processing information taking conversion information into consideration. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention as claimed, and not all combinations of features described in the embodiments are necessarily essential to the invention. Two or more of the features described in the embodiments may be arbitrarily combined. Furthermore, the same reference numerals are used for the same or similar components, and redundant explanations will be omitted.

[0010] First Embodiment FIG. 1 is a configuration diagram of a wireless communication system used to explain an embodiment. An access point (AP) 2 is a communication device capable of wireless communication with wireless devices (WDs) 1-1 to 1-4 and is also called a base station (BS). WDs 1-1 to 1-4 are communication devices capable of wireless communication with AP 2. As an example, WDs 1-1 to 1-4 are IoT devices. In the following explanation, WDs 1-1 to 1-4 will also be collectively referred to as WD1. In the example shown in FIG. 1, AP 2 accommodates four WDs 1. In the following explanation, the direction from WD 1 to AP 2 will be referred to as the uplink direction, and the direction from AP 2 to WD 1 will be referred to as the downlink direction. AP 2 is connected to a communication network (not shown), and AP 2 has a function of relaying communication between WD 1 and a server of the communication network (not shown).

[0011] 2 is a diagram showing an example of the configuration of WD1 and AP2. WD1 and AP2 include a modulator 3, a demodulator 4, a storage unit 5, and a radio unit 6. The modulator 3 includes a mapping unit 31, a conversion unit 32, a processing unit 33, and a conversion unit 34. The demodulator 4 includes a conversion unit 44, a processing unit 43, a conversion unit 42, and a determination unit 41. The storage unit 5 stores transmission information and reception information. The transmission information is information used on the transmitting side of the modulator 3 and the radio unit 6, and the reception information is information used on the receiving side of the demodulator 4 and the radio unit 6. The transmission information and reception information will be described in detail later, but they are used at N different times t1 to t (N is an integer of 2 or more). N and N times t1 to t N and frequency information indicating the frequency at each of the frequencies.

[0012] U1, U2, V1, and V2 shown in FIG. 2 are all numerical sequences of N complex numbers. Also, W1, W2, S, and R shown in FIG. 2 are all numerical sequences of M complex numbers. N is an integer equal to or greater than 2, and M is an integer equal to or greater than N. In the following explanation, the N numerical sequences correspond to an N-dimensional vector. Also, the N-dimensional vector {e1, e2, e3, . . . , e N}N elements e1 to e NWhen distinguishing between elements, the left element is written as the "first element." Therefore, e2 is the second element, and e N is the Nth element. Furthermore, in the following explanation, it is assumed that an "N-dimensional vector" is also an "N-row, 1-column matrix." Note that the first element of an N-dimensional vector corresponds to the element in the first row (topmost element) of an N-row, 1-column matrix, and the Nth element of an N-dimensional vector corresponds to the element in the N-row (bottommost element) of an N-row, 1-column matrix. The same applies to M number sequences.

[0013] The mapping unit 31 outputs an N-dimensional vector U1 based on the data to be transmitted (transmission data). The conversion unit 32 outputs an N-dimensional vector V1, which is the product of a regular matrix A of size N (N rows and N columns) and the vector U1. The regular matrix A is a complex square matrix, and the inverse matrix A, whose product with the matrix A is a unit matrix, is -1 There exists an inverse matrix A -1 For example, if matrix A is a unitary matrix, then matrix A and its adjoint matrix A are * The product of this and the matrix A is the identity matrix. * is a matrix obtained by taking the complex conjugate of each element (component) of matrix A and transposing it. Naturally, the adjoint matrix A of matrix A is * is also a unitary matrix.

[0014] The processing unit 33 calculates the time t indicated by the transmission information based on the vector V1. n (n is an integer between 1 and N) The corresponding M-dimensional vector W1(t n ) is output. The details of the processing in the processing unit 33 will be described later. The conversion unit 34 converts a regular matrix B of size M (M rows and M columns) and a vector W1(t n ) at time t n M-dimensional vector S(t n ) The radio unit 6 outputs the vector S(t n ) at time t n is converted into a radio signal (transmitted signal) of frequency at time t n Send in order from

[0015] Furthermore, the radio unit 6 receives the time t n A radio signal (received signal) with a frequency at time t n Received in order from time t n M-dimensional vector R(t n The transform unit 44 outputs the inverse matrix B of the regular matrix B used by the transform unit 34 on the transmitting side. -1 and vector R(t n ) at time t n The M-dimensional vector W2(t n ) according to the received information. N ) and outputs an N-dimensional vector V2. The conversion unit 42 generates an inverse matrix A of the regular matrix A used by the conversion unit 32 on the transmitting side. -1 and vector V2, and outputs an N-dimensional vector U2. A determination unit 41 determines the transmitted data based on vector U2.

[0016] Any regular matrix can be used as the regular matrices A and B used in the transform unit 32 and the transform unit 34. In the following, as a specific example, the regular matrix A used in the transform unit 32 is expressed as a discrete Fourier transform (DFT) matrix M DFT The regular matrix B used in the transform unit 34 is defined as an inverse discrete Fourier transform (IDFT) matrix M IDFT Therefore, the inverse matrix B used in the conversion unit 44 is -1 is the discrete Fourier transform (DFT) matrix M DFT The inverse matrix A used in the conversion unit 42 is -1 is the inverse discrete Fourier transform (IDFT) matrix M IDFTIn this case, the processing performed by the transform units 32 and 44 is discrete Fourier transform processing, and the processing performed by the transform units 34 and 42 is inverse discrete Fourier transform processing. The modulator 3 has a configuration in which a mapping unit 31 and a processing unit 33 are added to a configuration in which an IDFT is performed after a DFT, which is used in a normal DFT spread-OFDM demodulator. Similarly, the demodulator 4 has a configuration in which a processing unit 43 and a determination unit 41 are added to a configuration in which an IDFT is performed after a DFT, which is used in a normal DFT spread-OFDM demodulator.

[0017] [When M=N] In the following description, it is assumed that M=N in order to facilitate understanding of the embodiment.

[0018] DFT matrix M of size N DFT and IDFT matrix M IDFT is ω=e -j2π / N Then, the equation is as follows: Note that coefficients that are commonly multiplied by each element are omitted.

[0019]

number

[0020] In the following, for the sake of simplicity, when specific numerical values ​​are exemplified, N=4 (hence, M=4 in this example) is used. However, the value of N can be any value equal to or greater than 2, and the value of M can be any value equal to or greater than N. When N=4, the DFT matrix M DFT and IDFT matrix M IDFT becomes as follows:

[0021]

number

[0022] The mapping unit 31 of the modulator 3 and the decision unit 41 of the demodulator 4 have mapping information. The mapping information is information indicating the correspondence between data and N-dimensional reference vectors. In this embodiment, the reference vector is a vector in which one of N elements has a complex value "α" different from 0, and the other (N-1) elements have values ​​of "0". Therefore, the total number of reference vectors is N. In the following description, a reference vector whose nth element (n is an integer from 1 to N) has the value α will be referred to as the "nth reference vector". Since the total number of reference vectors is N, the number of data bits P mapped to one reference vector is log2N or less.

[0023] Fig. 3 shows an example of mapping information when N=4. According to the mapping information in Fig. 3, data "00" is mapped to the first reference vector, i.e., {α, 0, 0, 0}. Note that the mapping information shown in Fig. 3 is an example, and a reference vector different from the first reference vector can be associated with data "00". In this embodiment, the non-zero element positions of the reference vector indicate data.

[0024] <Upstream communication> First, upstream communication will be described. In the following description, it is assumed that the transmission information shown in FIG. 4(A) is stored in the storage unit 5 of WD1-1, the transmission information shown in FIG. 4(B) is stored in the storage unit 5 of WD1-2, the transmission information shown in FIG. 4(C) is stored in the storage unit 5 of WD1-3, and the transmission information shown in FIG. 4(D) is stored in the storage unit 5 of WD1-4. On the other hand, it is assumed that the reception information shown in FIG. 4(A) is stored in association with WD1-1, the reception information shown in FIG. 4(B) is stored in association with WD1-2, the reception information shown in FIG. 4(C) is stored in association with WD1-3, and the reception information shown in FIG. 4(D) is stored in association with WD1-4 in the storage unit 5 of AP2. Note that the transmission information used on the transmitting side and the reception information used on the receiving side are the same information, so in the following description, "transmission information" and "reception information" will be collectively referred to as "processing information."

[0025] The processing information is from the first time t1 to the Nth time tN 4A to 4D is for the case where N=4, so the time information indicates four times, the first time t1 to the fourth time t4, the frequency information indicates the frequency at each of the four times, and the element information indicates a one-to-one correspondence between each of the first time t1 to the fourth time t4 and the four elements of the four-dimensional vector.

[0026] Each time indicated by the time information is the elapsed time from a periodic reference time. In other words, the first time t1 to the fourth time t4 are periodic times. In this example, the first time t1 is earlier than the second time t2, the second time t2 is earlier than the third time t3, and the third time t3 is earlier than the fourth time t4. However, the relationship between the first time t1 to the fourth time t4 is not limited to the above relationship. For example, the first time t1 may be the second earliest time, the third earliest time, or the latest time of the four times. The same applies to the other times. More generally, the first time t1 to the Nth time t N The "1st" to "Nth" are used to distinguish the N times, and do not indicate the order on the time axis.

[0027] Furthermore, in the frequency information of the processing information shown in Figures 4(A) to 4(D), the frequencies at the four times are different, but the frequencies at at least two of the four times may be the same.

[0028] When N = 4, the element information is obtained by cyclically shifting the order of the "first" to the "fourth" elements within the range of shift amounts from 0 to 3. Specifically, for the element information in Fig. 4(A), in the order of the first time t1 to the fourth time t4, the elements corresponding to the times are in the order of the first element to the fourth element. Then, the element information in Fig. 4(B), Fig. 4(C), and Fig. 4(D) is obtained by cyclically shifting the order of the element positions shown in the element information of Fig. 4(A) to the right by shift amounts of "1", "2", and "3", respectively.

[0029] In the following description, the element information in which the element corresponding to the first time is the first element is also referred to as the first element information, the element information in which the element corresponding to the second time is the first element is also referred to as the second element information, the element information in which the element corresponding to the third time is the first element is also referred to as the third element information, and the element information in which the element corresponding to the fourth time is the first element is also referred to as the fourth element information. Also, as shown in Figs. 4(A) to 4(D), the processing information including the first element information is also referred to as the first processing information, the processing information including the second element information is also referred to as the second processing information, the processing information including the third element information is also referred to as the third processing information, and the processing information including the fourth element information is also referred to as the fourth processing information.

[0030] Generally speaking, it is possible to create N different processing information including the same time information and frequency information but different element information, that is, the first processing information to the Nth processing information. The kth processing information (k is an integer from 1 to N) includes the kth element information, and the kth element information indicates the xth element of the N-dimensional vector as an element of the N-dimensional vector corresponding to the nth time, where x is the value obtained by adding 1 to the remainder of dividing (N + n - k) by N. That is, x = {(N + n - k) mod N} + 1. Here, "mod" indicates the remainder operation.

[0031] <Upward communication by WD1-1> The following describes a case where WD1-1 transmits data "10" to AP2. In the following description, for simplicity of notation, it is assumed that "α" in the mapping information in FIG. 3 is 1. In this embodiment, the mapping unit 31 outputs the reference vector corresponding to the data as vector U1. That is, in this example, since the data is "10", the mapping unit 31 of WD1-1 outputs the third reference vector {0,0,1,0} as vector U1. The conversion unit 32 of WD1-1 performs a discrete Fourier transform on this vector U1 and outputs vector V1. Vector V1 is as follows:

[0032]

number

[0033] The processing unit 33 of the WD1-1 refers to the first processing information (FIG. 4A) stored in the storage unit 5 of the WD1-1, and calculates the time t n Vector W1(t n ) is output. According to the processing information shown in FIG. 4(A), the first element corresponds to time t1. In this case, the processing unit 33 of WD1-1 extracts only the first element of the four elements of vector V1 and outputs vector W1(t1) by setting the remaining elements to 0. The same applies to vectors W1(t2) to W1(t4). Therefore, W1(t1) = {1, 0, 0, 0}, W1(t2) = {0, -1, 0, 0}, W1(t3) = {0, 0, 1, 0}, and W1(t4) = {0, 0, 0, -1}.

[0034] The conversion unit 34 of WD1-1 converts the vector W1(t n ) and calculate the time t n Vector S(t n ) is output. The vectors S(t1) to S(t4) are shown below.

[0035]

number

[0036] From time t1 to time t4, the radio unit 6 of WD1-1 converts the vectors S(t1) to S(t4) output by the conversion unit 34 into radio signals having the frequencies for the corresponding times indicated by the frequency information, and transmits them to the AP 2. In FIG. 4A, the frequencies from time t1 to t4 are frequencies f1 to f4. Therefore, in accordance with the first processing information, the radio unit 6 transmits a radio signal corresponding to the numerical sequence indicated by the vector S(t1) at frequency f1 from time t1 to time t1+3, transmits a radio signal corresponding to the numerical sequence indicated by the vector S(t2) at frequency f2 from time t2 to time t2+3, transmits a radio signal corresponding to the numerical sequence indicated by the vector S(t3) at frequency f3 from time t3 to time t3+3, and transmits a radio signal corresponding to the numerical sequence indicated by the vector S(t4) at frequency f4 from time t4 to time t4+3. Note that the period during which one complex value of the vector S is transmitted is defined as "1." The radio signal corresponding to the vector S can be generated by associating the complex values ​​indicated by each element of the vector S with a constellation of quadrature amplitude modulation (QAM). Fig. 5 shows the signal transmitted by WD1-1. Note that in this embodiment, the numerical sequence indicated by the vector S is transmitted in ascending order of the element numbers, but it can also be transmitted in descending order.

[0037] The wireless unit 6 of the AP 2 performs the first process according to the first process information shown in FIG. n ~t n +3 between vector S(t n ) and receives a radio signal corresponding to time t n Vector R(t n ) is output from the conversion unit 44 of the AP2. n ) and calculate the time t n Vector W2(t n ) is output. Assuming that there is no influence of interference or noise in the wireless section, R(t n )=S(t n ) The matrix B used by the conversion unit 44 *is the inverse matrix of matrix B used by conversion unit 34. Therefore, vectors W2(t1) to W2(t4) output by conversion unit 44 are the same as W1(t1) to W1(t4). That is, W2(t1)={1,0,0,0}, W2(t2)={0,-1,0,0}, W2(t3)={0,0,1,0}, and W2(t4)={0,0,0,-1}.

[0038] The processing unit 43 of AP2 outputs vector V2 based on vectors W2(t1) to W2(t4) in accordance with the first processing information. Specifically, because the element corresponding to time t1 is the first element, the processing unit 43 of AP2 extracts the first element of vector W2(t1) corresponding to time t1 and sets it as the first element of vector V2. Similarly, because the elements corresponding to times t2, t3, and t4 are the "second element," "third element," and "fourth element," the processing unit 43 of AP2 extracts the second element of vector W2(t2) corresponding to time t2, the third element of vector W2(t3) corresponding to time t3, and the fourth element of vector W2(t4) corresponding to time t4 and sets them as the second, third, and fourth elements of vector V2. Therefore, the processing unit 43 of AP2 outputs {1, -1, 1, -1}, the same as vector V1, as vector V2.

[0039] The transform unit 42 of AP2 performs an inverse discrete Fourier transform on the vector V2 and outputs a vector U2. Therefore, the vector U2 output by the transform unit 42 is as follows:

[0040]

number

[0041] The determination unit 41 of AP2 determines which reference vector was used on the transmission side based on the element position with the maximum absolute value among the four elements of the vector U2 and the mapping information shown in FIG. 3, and determines the data transmitted by WD1-1 based on the determined reference vector. Since the element with the maximum absolute value among the four elements of the vector U2 is the third element, the determination unit 41 of AP2 determines that the third reference vector was used on the transmission side based on the mapping information, and thus can determine that WD1-1 transmitted the data "10".

[0042] <Upward communication by WD1-2> Subsequently, the case where WD1-2 transmits the data "11" to AP2 will be described. Since it is the data "11", the mapping unit 31 of WD1-2 outputs the fourth reference vector as the vector U1. That is, the vector U1 output by the mapping unit 31 of WD1-2 is {0, 0, 0, 1}. The conversion unit 32 of WD1-2 performs a discrete Fourier transform on this vector U1 and outputs a vector V1. The vector V1 is as follows.

[0043] [Number]

[0044] According to the second processing information (FIG. 4(B)) that WD1-2 has, the fourth element corresponds to the time t1. In this case, the processing unit 33 of WD1-2 extracts only the fourth element among the four elements of the vector V1 and outputs a vector W1(t1) with the remaining elements set to 0. The same applies to the vectors W1(t2), W1(t3), and W1(t4). Therefore, W1(t1) = {0, 0, 0, -j}, W1(t2) = {1, 0, 0, 0}, W1(t3) = {0, j, 0, 0}, and W1(t4) = {0, 0, -1, 0}.

[0045] The conversion unit 34 of WD1-2 performs an inverse discrete Fourier transform on the vector W1(t n ) and obtains a vector S(t n) is output. The vectors S(t1) to S(t4) are shown below.

[0046]

number

[0047] Therefore, the signal transmitted by the radio unit 6 of WD1-2 is as shown in FIG.

[0048] The wireless unit 6 of the AP2 calculates the vector S(t n ) and receive the radio signal corresponding to the vector R(t n ) is output. Assuming there is no interference or noise in the wireless section, R(t n )=S(t n ). Therefore, the vectors W2(t1) to W2(t4) output by the conversion unit 44 are the same as W1(t1) to W1(t4). That is, W2(t1)={0,0,0,-j}, W2(t2)={1,0,0,0}, W2(t3)={0,j,0,0}, and W2(t4)={0,0,-1,0}.

[0049] The processing unit 43 of AP2 outputs vector V2 based on vectors W2(t1) to W2(t4) in accordance with the second processing information. Specifically, because the fourth element corresponds to time t1, the processing unit 43 of AP2 extracts the fourth element of vector W2(t1) and sets it as the fourth element of vector V2. Similarly, because the "first element," "second element," and "third element" correspond to times t2, t3, and t4, the processing unit 43 of AP2 extracts the first element of vector W2(t2), the second element of vector W2(t3), and the third element of vector W2(t4), and sets them as the first, second, and third elements of vector V2. Therefore, the processing unit 43 outputs {1, j, -1, -j}, the same as vector V1, as vector V2.

[0050] The conversion unit 42 of AP2 performs an inverse discrete Fourier transform on the vector V2 and outputs the vector U2. Therefore, the vector U2 output by the conversion unit 42 is as follows.

[0051] [Number]

[0052] Since the absolute value of the fourth element among the four elements of the vector U2 is the largest, the determination unit 41 of AP2 determines that WD1-2 has transmitted the data "11" based on the mapping information.

[0053] <Upward communication by WD1-3 and WD1-4> The upward communication by WD1-3 and WD1-4 is the same as the upward communication by WD1-1 and WD1-2. For example, although the calculation formula is omitted, if both WD1-3 and WD1-4 transmit the data "00", the signals transmitted by WD1-3 and WD1-4 to AP2 are as shown in FIG. 5. Note that the processing in AP2 is the same as that described for the upward communication by WD1-1 and WD1-2, so it is omitted.

[0054] <Downward communication> Next, downstream communication by AP2 will be described. As in the upstream communication, the storage unit 5 of AP2 stores the processing information shown in Figures 4(A) to 4(D) as transmission information in association with WD1-1 to WD1-4, the storage unit 5 of WD1-1 stores the processing information shown in Figure 4(A) as reception information, the storage unit 5 of WD1-2 stores the processing information shown in Figure 4(B) as reception information, the storage unit 5 of WD1-3 stores the processing information shown in Figure 4(C) as reception information, and the storage unit 5 of WD1-4 stores the processing information shown in Figure 4(D) as reception information. As in the upstream communication, it is assumed that data "10" is transmitted to WD1-1, data "11" is transmitted to WD1-2, data "00" is transmitted to WD1-3, and data "00" is transmitted to WD1-4. That is, in the description of upstream communication, the case where AP2 transmits the same data to each WD1 as that transmitted from each WD1 to AP2 will be described below as an example.

[0055] Furthermore, in the following description, vectors U1, V1, and W1 generated within AP2 based on data sent to WD1-1 will be referred to as U 1-1 , V 1-1 and W 1-1 The vectors U1, V1, and W1 generated within AP2 based on the data sent to WD1-2 are denoted as U 1-2 , V 1-2 and W 1-2 The vectors U1, V1, and W1 generated in AP2 based on the data sent to WD1-3 are denoted as U 1-3 , V 1-3 and W 1-3 The vectors U1, V1, and W1 generated in AP2 based on the data sent to WD1-4 are denoted as U 1-4 , V 1-4 and W 1-4 It is written as follows.

[0056] From the mapping information shown in Figure 3, the vector U 1-1 ={0,0,1,0}, and the vector U 1-2 ={0,0,0,1}, and the vector U 1-3={1,0,0,0}, and the vector U 1-4 ={1,0,0,0}. Vector U 1-1 ={0,0,1,0} to vector V 1-1 The formula for calculating the vector U is as shown in Equation 1. 1-2 ={0,0,0,1} to vector V 1-2 The formula for calculating the vector U is as shown in Equation 7. 1-3 ={1,0,0,0} to vector V 1-3 The formula for calculating the vector U 1-4 ={1,0,0,0} to vector V 1-4 The formula for calculating the vector V is omitted. 1-1 ~V 1-4 is as shown in Figure 6.

[0057] The processing unit 33 of AP2 calculates the vector V based on the first processing information (FIG. 4A) associated with WD1-1. 1-1 Processing W 1-1 (t1)~W 1-1 Generate (t4). W 1-1 (t n ) is the time t based on the data sent to WD1-1. n is the vector corresponding to W 1-1 (t n ) is the vector W1(t n Similarly, the processing unit 33 of AP2 calculates the vector V based on the second processing information (FIG. 4B) associated with WD1-2. 1-2 Processing W 1-2 (t1)~W 1-2 Generate (t4). W 1-2 (t n ) is the vector W1(t n ) is the same.

[0058] Similarly, the processing unit 33 of AP2 calculates the vector V based on the third processing information (FIG. 4C) associated with WD1-WD3. 1-3 Processing W 1-3(t n ) is generated by using the third processing information shown in FIG. 4(C) and the vector V 1-3 As is clear from the above, the vector W 1-3 (t n ) is as shown in Figure 6. Note that the vector W 1-3 (t n ) is the vector W1(t n ) is the same as the vector V 1-4 Processing W 1-4 (t n ) is generated by using the fourth processing information shown in FIG. 4(D) and the vector V 1-4 As is clear from the above, the vector W 1-4 (t n ) is as shown in Figure 6. Note that the vector W 1-4 (t n ) is the vector W1(t n ) is the same.

[0059] The processing unit 33 of the AP2 further 1-1 (t1)~W 1-4 (t1) is added to the vector and output as vector W1(t1), and W 1-1 (t2)~W 1-4 (t2) is added to the vector W1(t2) and output as W 1-1 (t3)~W 1-4 (t3) is added to the vector W1(t3) and output as W 1-1 (t4)~W 1-4 The vector to which W1(t1) and W1(t4) have been added is output as vector W1(t4). W1(t1) to W1(t4) are also shown in FIG.

[0060] The transformation unit 34 of AP2 transforms the vector W1(t n ) to obtain the vector S(t n ) is output. The vectors S(t1) to S(t4) are shown below.

[0061]

number

[0062] The vectors S(t1) to S(t4) transmitted by AP2 from times t1 to t4 respectively correspond to the signals transmitted by WD1-1 to WD1-4 from S(t1) to S(t4) as described in the upstream communication, i.e., the sum of the signals shown in Figure 5.

[0063] Assuming that there is no influence of interference or noise in the wireless section, the vector R(t n )=S(t n ) Therefore, the vectors W2(t1) to W2(t4) output by the conversion unit 44 of each WD1 are the same as W1(t1) to W1(t4) shown in FIG.

[0064] The processing unit 43 of WD1-1 outputs a vector V2 based on the vectors W2(t1) to W2(t4) in accordance with the first processing information shown in FIG. 4(A). Specifically, since the first element corresponds to time t1, the processing unit 43 of WD1-1 extracts the first element of vector W2(t1) and sets it as the first element of vector V2. Similarly, since the second element, third element, and fourth element correspond to times t2, t3, and t4, respectively, the processing unit 43 of WD1-1 extracts the second element of vector W2(t2), the third element of vector W2(t3), and the fourth element of vector W2(t4), and sets them as the second, third, and fourth elements of vector V2. In other words, the processing unit 43 of WD1-1 outputs vector V2 based on the vectors W2(t1) to W2(t4). 1-1 will output the same {1,-1,1,-1}.

[0065] The transformation unit 42 of WD1-1 performs an inverse discrete Fourier transform on the vector V2 and outputs the vector U2. The vector U2 output by the transformation unit 42 of WD1-1 is as shown in Equation 6. Therefore, the determination unit 41 of WD1-1 determines that the third reference vector was used on the transmitting side based on the mapping information, and can therefore determine that AP2 transmitted data "10".

[0066] The processing unit 43 of WD1-2 outputs vector V2 based on vectors W2(t1) to W2(t4) in accordance with the second processing information shown in Fig. 4(B). Specifically, since the fourth, first, second, and third elements correspond to times t1, t2, t3, and t4, respectively, the processing unit 43 of WD1-2 extracts the fourth element of vector W2(t1), the first element of vector W2(t2), the second element of vector W2(t3), and the third element of vector W2(t4) to set them as the fourth, first, second, and third elements of vector V2. In other words, the processing unit 43 of WD1-2 outputs vector V2 based on vectors W2(t1) to W2(t4). 1-2 will output the same {1,j,-1,j}.

[0067] The transformation unit 42 of WD1-2 performs an inverse discrete Fourier transform on the vector V2 and outputs the vector U2. The vector U2 output by the transformation unit 42 of WD1-2 is as shown in Equation 12. Therefore, the determination unit 41 of WD1-2 determines that the fourth reference vector was used on the transmitting side based on the mapping information, and can therefore determine that AP2 transmitted data "11."

[0068] The processing unit 43 of WD1-3 outputs the vector V2 based on the vectors W2(t1) to W2(t4) in accordance with the third processing information shown in Fig. 4(C). Although a detailed description will be omitted, the vector V2 output by the processing unit 43 of WD1-3 is 1-3It becomes {1, 1, 1, 1} which is the same as [the previous one]. The conversion unit 42 of WD1-3 performs the inverse discrete Fourier transform of the vector V2 and outputs the vector U2. Although the calculation formula is omitted, the vector U2 output by the conversion unit 42 of WD1-3 becomes {4, 0, 0, 0}. Therefore, the determination unit 41 of WD1-3 determines that the first reference vector is used on the transmission side based on the mapping information, and thus can determine that AP2 has transmitted the data "00".

[0069] The processing unit 43 of WD1-4 outputs the vector V2 based on the vectors W2(t1) to W2(t4) according to the fourth processing information shown in FIG. 4(D). Although detailed explanation is omitted, the vector V2 output by the processing unit 43 of WD1-4 is the vector V 1-4 It becomes {1, 1, 1, 1} which is the same as [the previous one]. The conversion unit 42 of WD1-4 performs the inverse discrete Fourier transform of the vector V2 and outputs the vector U2. Although the calculation formula is omitted, the vector U2 output by the conversion unit 42 of WD1-4 becomes {4, 0, 0, 0}. Therefore, the determination unit 41 of WD1-4 determines that the first reference vector is used on the transmission side based on the mapping information, and thus can determine that AP2 has transmitted the data "00".

[0070] <Summary when M = N> As shown in FIG. 5, the vector S(t1) transmitted by WD1-1 from time t1, the vector S(t2) transmitted from time t2, the vector S(t3) transmitted from time t3, and the vector S(t4) transmitted from time t4 are the first column, the second column, the third column, and the fourth column vectors of the IDFT matrix M IDFT correspond to those obtained by circularly shifting the vectors of the first column, the second column, the third column, and the fourth column of the IDFT matrix M to the right (downward when regarded as a matrix of N rows and 1 column) by 2. The reason for corresponding to those circularly shifted to the right by 2 is that in the mapping information, the position of the value "α" in the third reference vector corresponding to the data "10" is the third element shifted 2 to the right from the first element. Also, the vectors S(t1), S(t2), S(t3), and S(t4) are the IDFT matrix M IDFTThe reason why they correspond to the first, second, third and fourth columns is that in the first processing information used by WD1-1, the "first element", "second element", "third element" and "fourth element" correspond to times t1, t2, t3 and t4, respectively.

[0071] Similarly, as shown in FIG. 5, the vector S(t1) transmitted by WD1-2 from time t1, the vector S(t2) transmitted from time t2, the vector S(t3) transmitted from time t3, and the vector S(t4) transmitted from time t4 are expressed as the IDFT matrix M IDFT The reason why it corresponds to a cyclic shift of 3 to the right (downward when considered as an N-row, 1-column matrix) is that in the mapping information, the position of the value "α" in the fourth reference vector corresponding to the data "11" is the fourth element, shifted three positions to the right from the first element. Also, the vectors S(t1), S(t2), S(t3), and S(t4) correspond to a cyclic shift of 3 to the right of the IDFT matrix M IDFT The reason why they correspond to the fourth, first, second and third columns is that in the second processing information used by WD1-2, the "fourth element", "first element", "second element" and "third element" correspond to times t1, t2, t3 and t4, respectively.

[0072] Similarly, as shown in FIG. 5, the vector S(t1) transmitted by WD1-3 from time t1, the vector S(t2) transmitted from time t2, the vector S(t3) transmitted from time t3, and the vector S(t4) transmitted from time t4 are expressed as the IDFT matrix M IDFT The reason why it corresponds to a cyclic shift by 0 to the right (downward when considered as a matrix with N rows and 1 column) of the vectors in the third, fourth, first and second columns of the above is that in the mapping information, the position of the value "α" in the first reference vector corresponding to the data "00" is the first position, that is, the amount of shift to the right is 0. Also, the vectors S(t1), S(t2), S(t3) and S(t4) correspond to a cyclic shift by 0 to the right (downward when considered as a matrix with N rows and 1 column). IDFTThe reason why the third, fourth, first and second columns correspond to the times t1, t2, t3 and t4 in the third processing information used by WD1-3 is that the "third element", "fourth element", "first element" and "second element" correspond to the times t1, t2, t3 and t4, respectively. The same applies to the vectors S(t1), S(t2), S(t3) and S(t4) sent by WD1-4.

[0073] 5, WD1-1 to WD1-4 transmit vector S(t1) at the same frequency f1 from time t1 to time t1+3, transmit vector S(t2) at the same frequency f2 from time t2 to time t2+3, transmit vector S(t3) at the same frequency f3 from time t3 to time t3+3, and transmit vector S(t4) at the same frequency f4 from time t4 to time t4+3. Therefore, AP2 receives a signal that combines the wireless signals from WD1-1 to WD1-4. This signal corresponds to the signal transmitted by AP2 in the description of the downlink direction. As described in the description of the downlink direction, WD1-1 can determine the data value transmitted by AP2 to WD1-1 from the signal that combines signals addressed to other WD1s by using the first processing information shown in FIG. 4(A). Similarly, by using the second processing information shown in Fig. 4(B), WD1-2 can determine the data value transmitted by AP2 to WD1-2 from a signal that is a composite of signals addressed to other WD1s. The same is true for WD1-3 and WD1-4. Therefore, in upstream communications, AP2 also receives a wireless signal that is a composite of signals from WD1-1 to WD1-4, but by using the processing information associated with each WD1, it can correctly determine the data transmitted by each WD1.

[0074] In this way, AP2 can perform uplink communication and downlink communication with N WD1s using the same time and frequency resources. In the above description, for simplicity, the processing information used by WD1 and AP2 in uplink communication and the processing information used by WD1 and AP2 in downlink communication are the same. However, the processing information used by WD1 and AP2 in uplink communication and the processing information used by WD1 and AP2 in downlink communication are different. In other words, the processing information used in uplink communication and the processing information used in downlink communication are configured to have a frequency division duplex (FDD) configuration in which the frequencies used in uplink communication and the frequencies used in downlink communication are different, or a time division duplex (TDD) configuration in which the time periods for uplink communication and the time periods for downlink communication are alternately provided.

[0075] In the above explanation, it was assumed that there was no influence of interference, noise, etc. in the wireless section. If the influence of interference, noise, etc. in the wireless section were taken into consideration, the vectors R(t1) = S(t1), R(t2) = S(t2), R(t3) = S(t3), and R(t4) = S(t4) would not hold. In this case, vector V2 and vector U2 would also deviate from the values ​​used in the above explanation. For example, in the case of uplink communication via WD1-1, vector U2 shown in equation 6 is {0,0,4,0}, but due to interference, noise, etc., the first, second, and fourth elements could have values ​​other than "0," and the third element could have a value other than "4."

[0076] The greater the interference and noise, the greater the amount of change from "0" of the values ​​of the first, second, and fourth elements, and the greater the amount of change from "4" of the value of the third element. However, as long as the absolute value of the third element is greater than the absolute values ​​of the other elements, the data transmitted by the transmitting side can be correctly determined by the receiving side. For example, in the processing information of FIG. 4, the transmission start time of each vector S and the frequency used to transmit each vector S are different. Therefore, the probability that all four vectors S are strongly affected by interference and noise is reduced. Therefore, the probability that the absolute value of the element position corresponding to data in vector U2 is smaller than the absolute values ​​of the other element positions can be reduced, and the probability of bit errors occurring can be reduced.

[0077] In the processing information shown in FIG. 4, each vector S is transmitted at a different frequency, but two or more vectors S can also be transmitted at the same frequency. For example, all of the vectors S can be transmitted at the same frequency. However, time information is set so that the transmission periods of two or more vectors S transmitted at the same frequency do not overlap. Conversely, the transmission periods of two or more vectors transmitted at different frequencies may overlap. In other words, N vectors S are transmitted using different resources. Different resources means that at least one of the time and frequency is different.

[0078] As described above, the AP2 can communicate with N WD1s by using N pieces of processing information including the same time information and frequency information, but one WD1 can also use two or more pieces of processing information. In this case, the processing performed by the WD1 using two or more pieces of processing information is the same as the processing performed by the AP2 described above. However, in the processing performed by the AP2 described above, the AP2 communicates with multiple WD1s using multiple pieces of processing information, but a WD1 using two or more pieces of processing information communicates with the same AP2 using two or more pieces of processing information.

[0079] Furthermore, one AP2 can communicate with more than N WDs1. For example, a set of N WDs1 using N pieces of processing information with the same time information and frequency information is defined as a "cluster." Here, the nth WD1 (n is an integer from 1 to N) in a cluster uses the nth processing information. The more than N WDs1 are classified into multiple clusters. For example, if two clusters, cluster #1 and cluster #2, are provided, the AP2 can communicate with a maximum of 2×N WDs1. Here, the time information and frequency information of the processing information used by the WDs belonging to cluster #1 are the same, and the time information and frequency information of the processing information used by the WDs belonging to cluster #2 are the same. However, at least one of the time information and frequency information included in the processing information used by the WDs belonging to cluster #1 is made different from that included in the processing information used by the WDs belonging to cluster #2. Specifically, the processing information used by WD1 in cluster #1 and the processing information used by WD1 in cluster #2 are set so that WD1 in cluster #1 and WD1 in cluster #2 do not transmit vector S using the same frequency at the same time.

[0080] As an example, clusters can be configured as shown in Fig. 7. In Fig. 7, a total of G x H clusters are configured from cluster #1-1 to cluster #GH. Here, G and H are integers equal to or greater than 1. The H clusters from cluster #g-1 to cluster #gH are configured at a frequency f g Only time information #h is used, where g is an integer between 1 and G. Furthermore, G clusters #1-h to #Gh use the same time information #h. Here, h is an integer between 1 and H. The sets of N times (start timings of transmission and reception) indicated by each of the time information #1 to #H are different. Note that different time information means that at least one of the N times indicated by the time information is different. The value of H is determined based on the amount of interference caused by signals transmitted at the same frequency by multiple WD1s belonging to different clusters. Note that the same WD1 can also belong to different clusters simultaneously using the processing information of each cluster.

[0081] The processing information is stored in advance in the storage unit 5 of the AP2 and the WD1 by any method. For example, the processing information may be stored in the storage unit 5 of the WD1 when the WD1 is sold or when the WD1, which is an IoT device, is installed. An operator who operates the AP2 may store the processing information to be used in communication with a newly installed or sold WD1 in the storage unit 5 of the AP2 via a control interface of the AP2 (not shown). Alternatively, all processing information to be used by the AP2 in the future may be stored in advance in the storage unit 5 of the AP2, and when the WD1 is installed or sold, the operator who operates the AP2 may notify the AP2 of the processing information to be used in communication with the newly installed or sold WD1 via the control interface.

[0082] Furthermore, in a configuration in which all processing information to be used by AP2 in the future is stored in advance in the storage unit 5 of AP2, WD1 can obtain the processing information to be used by WD1 from AP2. Specifically, the configuration is such that WD1 and AP2 can communicate with each other via control signaling (not shown). Note that communication via control signaling uses any existing communication method. When powered on, WD1, which does not have processing information stored in the storage unit 5, accesses AP2 via control signaling to request processing information. AP2 can select processing information to be used by WD1 from unused processing information and transmit the selected processing information to WD1 via control signaling.

[0083] [If M is greater than N] In the following, a case where M is greater than N will be described. When M is greater than N, the processing unit 33 calculates an M-dimensional vector W1(t n ), and the processing unit 43 outputs the M-dimensional vector W2(t n ) and outputs an N-dimensional vector V2. In the following explanation, N=4 and M=8, and the four-dimensional vector W1(t n ) and W2(t n ) into vector W1´(t n ) and W2´(t n) is written as

[0084] If M is greater than N, the storage unit 5 stores the conversion information. FIG. 10(A) shows an example of the conversion information. The conversion information is information indicating a one-to-one correspondence between four elements of a four-dimensional vector and four of the eight elements of an eight-dimensional vector. The processing unit 33 converts the four-dimensional vector W1'(t n ) into an 8-dimensional vector W1(t n ) and outputs it to the conversion unit 34. n ) that are not indicated in the conversion information, the processing unit 43 outputs the value of 0 to the conversion unit 34. Similarly, the processing unit 43 converts the eight-dimensional vector W2(t n ) into a four-dimensional vector W2´(t n ) and convert it into vector W2´(t n ) and outputs the vector V2 to the conversion unit 42.

[0085] According to Figure 10(A), the four-dimensional vector W1'(t n ) the first to fourth elements are the eight-dimensional vector W1(t n ) corresponds to the first to fourth elements. As explained in the upstream communication, when WD1-1 transmits data "10" to AP2, W1'(t1)={1,0,0,0}. Therefore, in the case of the conversion information of FIG. 10(A), the processing unit 33 of WD1-1 outputs W1(t1)={1,0,0,0,0,0,0,0} to the conversion unit 34.

[0086] Matrix B used by the conversion unit 34 of WD1-1 and matrix B used by the conversion unit 44 of AP2 * Since the product of is a unit matrix, ignoring the influence of the wireless section, the vector W2(t n ) is the vector W1(t n ) based on the conversion information shown in FIG. 10(A). n ) and extract the first to fourth elements of the vector W2´(t n) are the first to fourth elements. That is, W2'(t1) = {1,0,0,0}. The subsequent processing is the same as that explained for the case of N = M = 4.

[0087] The same applies to the downstream direction. For example, as described in the description of the downstream direction when N=M=4, assume that AP2 transmits data "10" to WD1-1, data "11" to WD1-2, and data "00" to WD1-3 and WD1-4. In this case, as shown in Figure 6, W1'(t1) = {1, 1, 1, -j}. When AP2 uses the conversion information of Figure 10(A), the processing unit 33 of AP2 outputs W1(t1) = {1, 1, 1, -j, 0, 0, 0, 0} to the conversion unit 34.

[0088] Ignoring the influence of the wireless section, the vector W2(t n ) is the vector W1(t n ) The processing unit 43 of each WD1 calculates the vector W2(t n ) and extract the first to fourth elements of the vector W2´(t n ) are the first to fourth elements. That is, W2'(t1) = {1,1,1,-j}. The subsequent processing is the same as that explained for the case of N = M = 4.

[0089] FIG. 10(B) shows another example of the transformation information. According to FIG. 10(B), the four-dimensional vector W1′(t n ) are the 8-dimensional vector W1(t n ) corresponds to the 1st, 3rd, 5th, and 7th elements of t. Therefore, when W1′(t)={1, 1, 1, -j}, the processing unit 33 outputs W1(t)={1, 0, 1, 0, 1, 0, -j, 0} to the conversion unit 34.

[0090] When M=N, the maximum number of WD1s in one cluster was N. On the other hand, when M is greater than N and the value obtained by dividing M by N is 2 or greater, the maximum number of WD1s in one cluster can be greater than N. Specifically, if the value obtained by dividing M by N and rounding down the decimal point is Z, the maximum number of WD1s in one cluster can be Z×N. In this example, M=8 and N=4, so Z is 2. Therefore, in this example, the maximum number of WD1s in one cluster can be 8.

[0091] In this case, one cluster includes two subclusters, subcluster #1 and subcluster #2. More generally, one cluster includes Z subclusters, subcluster #1 to subcluster #Z. When M=N, Z=1, so one cluster has only one subcluster, and the cluster and the subcluster are the same. Therefore, the cluster described when M=N is actually a description of a subcluster.

[0092] Sub-cluster #1 and sub-cluster #2 each include a maximum of four WD1s. The four WD1s in sub-cluster #1 use one of the first to fourth processing information shown in FIG. 4. The processing information used by the four WD1s in sub-cluster #1 is different from the processing information used by the other WD1s in sub-cluster #1. The same is true for sub-cluster #2. However, the four WD1s in sub-cluster #1 use the conversion information shown in FIG. 10(B), and the four WD1s in sub-cluster #2 use the conversion information shown in FIG. 10(C).

[0093] The conversion information shown in Fig. 10(B) associates four elements of a four-dimensional vector with odd-numbered elements of eight elements of an eight-dimensional vector, while the conversion information shown in Fig. 10(C) associates four elements of a four-dimensional vector with even-numbered elements of an eight-dimensional vector that are not used in the conversion information shown in Fig. 10(B).

[0094] The processing unit 33 of WD1 belonging to the sub-cluster #1 calculates the four-dimensional vector W1'(tn ) based on the transformation information in Figure 10(B), the 8-dimensional vector W1(t n ) The processing unit 33 of WD1 belonging to the sub-cluster #2 converts it into a four-dimensional vector W1'(t n ) based on the transformation information of Figure 10(C), the 8-dimensional vector W1(t n ) to receive data from WD1 belonging to sub-cluster #1. The processing unit 42 of AP2 uses the conversion information of FIG. 10(B) to convert the data into an eight-dimensional vector W2(t n ) into a four-dimensional vector W2´(t n ) to receive data from WD1 belonging to sub-cluster #2, the processing unit 42 of AP2 uses the conversion information of FIG. 10(C) to convert the data into an eight-dimensional vector W2(t n ) into a four-dimensional vector W2´(t n )

[0095] Furthermore, the processing unit 33 of the AP2 generates a four-dimensional vector W1'(t n ) based on the transformation information in Figure 10(B) and the 8-dimensional vector W 11 (t n ) and converts it into a four-dimensional vector W1'(t n ) based on the transformation information in Figure 10(C), the 8-dimensional vector W 12 (t n ) and the processing unit 33 of AP2 converts it into an eight-dimensional vector W 11 (t n ) and the eight-dimensional vector W 12 (t n ) and the vector obtained by adding them is the 8-dimensional vector W1(t n ) to the conversion unit 34.

[0096] For example, let us say that the processing unit 33 of AP2 generates W1'(t1)={1,1,1,-j} based on the data to be sent to the four WD1s of sub-cluster #1, and generates W1'(t1)={1,1,1,1} based on the data to be sent to the four WD1s of sub-cluster #2. In this case, the vector W 11 (t1)={1,0,1,0,1,0,-j,0}, and the vector W 12 (t1)={0,1,0,1,0,1,0,1}. Therefore, the vector W1(t1)={1,1,1,1,1,1,-j,1}.

[0097] Ignoring noise and the like in the wireless section, vector W1(t1) = vector W2(t1). Based on the conversion information shown in FIG. 10(B), processing unit 43 of WD1 belonging to subcluster #1 generates vector W2'(t1) = {1,1,1,-j}, which takes the first, third, fifth, and seventh elements of vector W2(t1) as the first, second, third, and fourth elements. Based on the conversion information shown in FIG. 10(C), processing unit 43 of WD1 belonging to subcluster #2 generates vector W2'(t1) = {1,1,1,1}, which takes the second, fourth, sixth, and eighth elements of vector W2(t1) as the first, second, third, and fourth elements. Subsequent processing is as already described, and the signals of subcluster #1 and subcluster #2 do not interfere with each other.

[0098] The processing unit 33 converts the N-dimensional vector V1 into the N-dimensional vector W1'(t n ) is generated, and then an N-dimensional vector W1'(t n ) into an M-dimensional vector W1(t n ), but by using element information that takes the conversion information into consideration, the processing unit 33 can convert the N-dimensional vector V1 into the M-dimensional vector W1(t n Similarly, the processing unit 43 can generate an M-dimensional vector W2(t n ) to generate an N-dimensional vector V1.

[0099] FIG. 11 shows element information after correction in which the element information of the first to fourth processing information shown in FIG. 4 is corrected in consideration of the conversion information shown in FIG. 10(B). According to FIG. 11, the element information is information indicating a one-to-one correspondence between the N times indicated by the time information and the N elements of the N-dimensional vector, and a one-to-one correspondence between the N times indicated by the time information and the N elements of the M-dimensional vector. In this example, since M=8 and N=4, "4" in the element information in FIG. 11 indicates an element of a four-dimensional vector, and "8" indicates an element of an eight-dimensional vector. The element information is also information indicating a one-to-one correspondence between elements of the N-dimensional vector and elements of the M-dimensional vector. The correspondence between elements of the N-dimensional vector and elements of the M-dimensional vector corresponding to the same time indicated by the time information is the same as the correspondence indicated by the conversion information shown in FIG. 10(B).

[0100] Fig. 12 shows corrected element information obtained by correcting the element information of the first to fourth processing information shown in Fig. 4 in consideration of the conversion information shown in Fig. 10(C). The only difference from the element information shown in Fig. 11 is the correspondence between the elements of the N-dimensional vector and the elements of the M-dimensional vector. The N elements of the M-dimensional vector indicated by the element information shown in Fig. 12 are all different from the N elements of the M-dimensional vector indicated by the element information shown in Fig. 11.

[0101] The time information and frequency information of the total eight pieces of processing information shown in Figures 11 and 12 are the same. On the other hand, the eight pieces of element information of the total eight pieces of processing information shown in Figures 11 and 12 are different. More specifically, the elements of the four-dimensional vector corresponding to each of the N times indicated by the element information in Figures 11(A) and 12(A) are the same, but the elements of the eight-dimensional vector corresponding to each of the N times are different. The same is true for the element information in Figures 11(B) and 12(B), the element information in Figures 11(C) and 12(C), and the element information in Figures 11(D) and 12(D).

[0102] 11 and 12, the kth processing information is a name based on the elements of the N-dimensional vector corresponding to each of the N time points. In other words, when x={(N+nk) mod N}+1, the kth processing information is processing information having element information indicating the xth element of the N-dimensional vector as the element of the N-dimensional vector corresponding to the nth time point. As shown in FIGS. 11 and 12, each sub-cluster has 1st to Nth processing information, but the N elements of the M-dimensional vector corresponding to each of the N time points indicated by the element information differ for each sub-cluster.

[0103] For example, when the first processing information in FIG. 11A is used for WD1-1 of sub-cluster #1, in the downstream direction, the processing unit 33 of AP2 processes a vector W whose first element is the first element of vector V1 and whose remaining elements are 0. 1-1 (t1), and the third element is the second element of vector V1, and the rest is 0. 1-1 (t2) and output a vector W whose fifth element is the third element of vector V1 and the rest are 0. 1-1 (t3) and output a vector W whose seventh element is the first element of vector V1 and the rest are 0. 1-1 Output (t4).

[0104] 12A is used for WD1-1 of sub-cluster #2, the processing unit 33 of AP2 in the downstream direction performs the processing for the vector W 1-1 (t1), and the fourth element is the second element of vector V1, and the rest are 0. 1-1 (t2) and output a vector W whose sixth element is the third element of vector V1 and the rest are 0. 1-1 (t3) and output a vector W whose 8th element is the 1st element of vector V1 and the rest are 0. 1-1 Output (t4).

[0105] Then, the processing unit 33 of AP2 calculates a total of eight vectors W generated for WD1-1 to WD1-4 of sub-cluster #1 and WD1-1 to WD1-4 of sub-cluster #2. 1-n (t n ) to obtain the vector W1(t n ) and outputs it to the conversion unit 34.

[0106] The processing unit 43 of WD1-1 in sub-cluster #1 using the first processing information of FIG. 11(A) outputs a vector V2 in which the first element of vector W2(t1) is the first element, the third element of vector W2(t2) is the second element, the fifth element of vector W2(t3) is the third element, and the seventh element of vector W2(t4) is the fourth element. The processing unit 43 of WD1-1 in sub-cluster #2 using the first processing information of FIG. 12(A) outputs a vector V2 in which the second element of vector W2(t1) is the first element, the fourth element of vector W2(t2) is the second element, the sixth element of vector W2(t3) is the third element, and the eighth element of vector W2(t4) is the fourth element. While only the downstream direction has been described, those skilled in the art will understand the upstream direction processing based on the above description, and therefore, a description thereof will be omitted.

[0107] 4, the n-th element of vector V1 is also the n-th element of vector W1, but as is clear from the above explanation, the n-th element of vector V1 can also be an element different from the n-th element of vector W1. Also, in the above specific example, the conversion unit 32 and the conversion unit 44 convert the discrete Fourier transform (DFT) matrix M DFT and the transform units 34 and 42 use an inverse discrete Fourier transform (IDFT) matrix M IDFT However, the inverse matrix A of the regular matrix A used by the transform unit 32 on the transmitting side is ―1 is used by the transform unit 42 on the receiving side, and the inverse matrix B of the regular matrix B used by the transform unit 34 on the transmitting side ―1As long as the transform unit 44 on the receiving side uses the above matrix A and matrix B, the matrices A and B are independent, and any type of regular matrix can be used as the matrices A and B.

[0108] As described above, according to this embodiment, it is possible to increase the number of wireless devices that can be accommodated in an AP.

[0109] Second Embodiment Next, the second embodiment will be described, focusing on the differences from the first embodiment. In the first embodiment, data is mapped to one of N reference vectors, and the mapped reference vector is defined as vector U1. Therefore, the number of bits P carried by vector U1 is log2N or less. In this embodiment, the number of bits carried by vector U1 is set to be more than log2N bits.

[0110] FIG. 8 shows an example of mapping information when N=4. In FIG. 8, the correspondence between the combination of the second and third bits of the three-bit data and one reference vector is the same as that of the mapping information of the first embodiment shown in FIG. 3. In this embodiment, the value of the first bit of the three-bit data is associated with a "multiplier." The mapping unit 31 generates a vector U1 by multiplying a reference vector determined based on the combination of the second and third bits by a multiplier determined based on the value of the first bit. In FIG. 8, as an example, if the first bit is "0," the multiplier is set to "1," and if the first bit is "1," the multiplier is set to "2."

[0111] For example, when WD1-1 transmits data "010" with α=1 as in the first embodiment, the multiplier is 1, and therefore the vector U2 at AP2 is {0,0,4,0}, the same as in equation 6. On the other hand, when WD1-1 transmits data "110", the multiplier is 2, and therefore the vector U2 at AP2 is {0,0,8,0}. The determination unit 41 of AP2 determines a reference vector based on the position of the element of vector U2 whose absolute value is maximum, and determines the multiplier based on the actual value of the element with the maximum absolute value. Then, the determination unit 41 determines the first bit of the 3-bit data based on the determined multiplier, and determines the second and third bits of the 3-bit data based on the determined reference vector.

[0112] The multiplier may be a negative value other than 0, or may be a complex value. For example, in FIG. 8, the multiplier is 2 when the first bit is 1, but the multiplier can also be −1 when the first bit is 1. In this case, the vector U2 corresponding to the data “110” is {0, 0, −4, 0}. Therefore, the determination unit 41 can determine whether the multiplier is 1 or −1. Furthermore, in FIG. 8, the multiplier is determined based on one bit, but a configuration is possible in which the multiplier is determined based on multiple bits. For example, the multiplier can be “1+j”, “−1+j”, “−1−j”, or “1−j” based on a combination of two-bit values.

[0113] In summary, in the first embodiment, a reference vector is determined based on P bits of data (P is an integer equal to or greater than 1), and the reference vector is directly used as vector U1, thereby transmitting P bits of data in one communication. Note that P is an integer equal to or less than log2N. On the other hand, in this embodiment, (P+Q) bits of data (Q is an integer equal to or greater than 1) are transmitted in one communication. The mapping unit 31 determines the reference vector based on P bits of data out of the (P+Q) bits of data. Furthermore, the mapping unit 31 determines a non-zero multiplier β based on Q bits of data out of the (P+Q) bits of data. Note that the number of multipliers β is 2 QThen, the mapping unit 31 generates a vector U1 by multiplying the reference vector determined based on the P bits by a multiplier β determined based on the Q bits. Therefore, the number of values ​​that the non-zero elements of the vector U1 can take is 2 Q It should be noted that, among the first to (P+Q)th bits constituting the (P+Q) bits, how to select the Q bits used to determine the multiplier and the P bits used to determine the reference vector can be arbitrarily selected, and is not limited to the configuration in which the multiplier is determined by the first Q bits.

[0114] Meanwhile, the determination unit 41 determines P-bit data based on the element position of the vector U2 with the largest absolute value. The determination unit 41 also determines a multiplier based on the actual value of the element position of the vector U2 with the largest absolute value, and determines Q-bit data based on the determined multiplier. This configuration allows the amount of data transmitted in one communication to be greater than in the first embodiment.

[0115] Third Embodiment Next, the third embodiment will be described, focusing on the differences from the above embodiments. In the first and second embodiments, the reference vector has N elements in which only one is α different from 0, and the remaining (N-1) elements are 0. In this embodiment, a reference vector is used in which γ elements (γ is an integer from 2 to (N-1)) out of N elements have α values ​​different from 0, and the remaining elements have 0 values.

[0116] FIG. 9 shows an example of mapping information when γ=2. For example, as in the first embodiment, if α=1 and vector U1 is the same as the reference vector, when WD1-1 transmits data "10," vector U1 is {0,0,1,1}. As is clear from the description of the first embodiment, assuming there is no noise or interference in the wireless section, vector U2 generated by AP2 is {0,0,4,4}. The determination unit 41 of AP2 can determine that WD1-1 transmitted data "10" because the two elements with the highest absolute value are the third and fourth elements. In other words, while the first embodiment maps data to one nonzero element of the reference vector, this embodiment maps data to a combination of γ nonzero elements among the N elements of the reference vector.

[0117] When N=4, if γ=2, the maximum number of reference vectors is 4C2=6, and when γ=3, the maximum number of reference vectors is 4C3=4. Therefore, the number of bits that can be mapped to one reference vector is 2 or less, as in the first embodiment. However, when N is greater than 4, the number of bits that can be mapped to one reference vector can be greater than log2N. As an example, when N=6, if γ=3, the maximum number of reference vectors can be 6C3=20. Therefore, in the first embodiment, even when N=6, the number of bits that can be mapped to one reference vector is 2, but in this embodiment, by setting γ=3, the number of bits that can be mapped to one reference vector can be increased to 4.

[0118] Thus, in this embodiment, the reference vector is a vector in which γ elements out of N elements are α and the remaining (N-γ) elements are 0. The mapping unit 31 determines the reference vector based on P-bit data and outputs the reference vector as vector U1. Therefore, the combination of the positions of elements whose values ​​in vector U1 are different from 0 indicates P-bit data. Here, the value of P is expressed as log2( N C γ) or less. Then, the decision unit 41 decides the P-bit data based on the combination of the positions of γ elements in the vector U2 in descending order of absolute value.

[0119] This embodiment can be combined with the second embodiment. In this case, the mapping unit 31 determines a reference vector based on P-bit data of the (P+Q)-bit data, and determines a non-zero multiplier β based on Q-bit data. The number of multipliers β is 2 Q Then, the mapping unit 31 generates a vector U1 by multiplying the reference vector determined based on the P bits by a multiplier β determined based on the Q bits. Therefore, the combination of the positions of elements whose values ​​in vector U1 are different from 0 indicates P-bit data, and the values ​​of elements of vector U1 that are different from 0 indicate Q-bit data. Here, the value of P is expressed as log2( N C γ ) or less. The determination unit 41 then determines P-bit data based on the combination of the positions of γ elements in vector U2 in descending order of absolute value, determines a multiplier based on the values ​​of γ elements in vector U2 in descending order of absolute value, and determines Q-bit data based on the determined multiplier. Note that the multiplier can be determined using a value calculated by a predetermined operation based on the actual values ​​of the γ elements, such as the average value of the γ elements with the highest absolute values. This makes it possible to carry more than log2N bits using an N-dimensional vector.

[0120] <Other> In each of the above embodiments, a configuration may be adopted in which a cyclic prefix (CP) is added to the vector S transmitted by WD1 or AP2, that is, a configuration in which a CP based on the vector S is transmitted immediately before or immediately after the vector S. As an example, the CP is the last C (C is an integer equal to or less than N) numerical sequence of the M numerical sequence of vector S. In this case, the CP is added immediately before vector S. In other words, WD1 and AP2 generate and transmit a CP-added vector S by adding a CP immediately before vector S. For example, if vector S is {-1, -j, 1, j} and C=2, the CP-added vector S becomes {1, j, -1, -j, 1, j}. As another example, the CP is the first C numerical sequence of the M numerical sequence of vector S. In this case, WD1 transmits the CP immediately after vector S. In other words, WD1 and AP2 generate and transmit a CP-added vector S by adding a CP immediately after vector S. For example, if vector S is {-1,-j,1,j} and C=2, vector S with CP becomes {-1,-j,1,j,-1,-j}. By adding CP, information can be demodulated accurately even in a multipath environment.

[0121] Furthermore, in each of the above embodiments, the WD1 and AP2 communicate wirelessly. However, the present invention is applicable to communication using, for example, sound waves or light, in addition to communication using radio signals in the radio frequency band. Furthermore, the communication methods and communication systems described in each of the above embodiments are provided.

[0122] Furthermore, a computer program is provided that causes an apparatus having one or more processors to function as the WD1 or AP2 described in each of the above embodiments. The computer program is stored in one or more memory devices of the apparatus, and includes program instructions that, when executed by one or more processors of the apparatus, cause the apparatus to function as the WD1 or AP2 described in each of the above embodiments. Furthermore, a computer program is provided that causes an apparatus having one or more processors to execute the communication method performed by the WD1 or AP2 described in each of the above embodiments. Furthermore, a non-transitory computer-readable storage medium storing these computer programs is provided.

[0123] The invention is not limited to the above-described embodiment, and various modifications and variations are possible within the scope of the gist of the invention. [Explanation of symbols]

[0124] 31: Mapping unit, 32, 33, 43, 44: Conversion units, 33, 43: Processing unit, 5: Storage unit, 6: Radio unit

Claims

1. A communication device, a storage means for storing processing information including time information indicating N times from a first time to an Nth time, frequency information indicating a frequency at each of the N times indicated by the time information, a one-to-one correspondence between the N times indicated by the time information and N elements of an N-dimensional vector, and element information indicating a one-to-one correspondence between the N times indicated by the time information and N elements of an M-dimensional vector, wherein N is an integer equal to or greater than 2 and M is an integer equal to or greater than N; mapping means for mapping the transmission data into an N-dimensional first vector; a first transformation means for transforming the first vector into an N-dimensional second vector by multiplying the first vector by a first regular matrix of size N; a processing means for performing processing to generate M-dimensional third vectors corresponding to the N time points based on the second vector in accordance with the element information, wherein a value of an element of the third vector corresponding to an n-th time point (n is an integer from 1 to N) is the same as a value of an element of the second vector corresponding to the n-th time point, and a value of an element of the third vector corresponding to the n-th time point that is different from the element corresponding to the n-th time point is 0; second conversion means for converting the third vector corresponding to the n time instant into an M-dimensional fourth vector corresponding to the n time instant by multiplying the third vector corresponding to the n time instant by a second regular matrix having a size M; a transmitting means for transmitting, from the nth time, M numerical sequences indicated by the fourth vector corresponding to the nth time using a signal having a frequency at the nth time indicated by the frequency information; A communication device comprising:

2. 2. The communication device according to claim 1, wherein the time information and the frequency information are set so that transmission periods of multiple fourth vectors transmitted at the same frequency, among the fourth vectors transmitted from the nth time, do not overlap.

3. The communication device according to claim 1, wherein the first vector is a vector in which the values ​​of γ elements (γ is an integer greater than or equal to 1 and less than or equal to (N-1)) out of N elements are different from 0, and the values ​​of (N-γ) elements are 0.

4. The value of γ is 1, the transmission data is P-bit data, The position of an element in the first vector that is different from 0 indicates the P bits of data; The value of P is log ２ The communication device according to claim 3 , wherein the number of the plurality of nodes is N or less.

5. The value of γ is 1, the transmission data is (P+Q)-bit data, The position of an element different from 0 in the first vector indicates P bits of data among the (P+Q) bits; The value of an element of the first vector that is different from 0 indicates Q bits of data among the (P+Q) bits, The value of P is log ２ The communication device according to claim 3 , wherein the number of the plurality of nodes is N or less.

6. the value of γ is 2 or more, the transmission data is P-bit data, a combination of positions of elements different from 0 in the first vector indicates the P bits of data; The value of P is log ２ ( Ｎ C γ 4. The communication device according to claim 3, wherein:

7. the value of γ is 2 or more, the transmission data is (P+Q)-bit data, A combination of positions of elements different from 0 in the first vector indicates P bits of data among the (P+Q) bits; The value of an element of the first vector that is different from 0 indicates Q bits of data among the (P+Q) bits, The value of P is log ２ ( Ｎ C γ 4. The communication device according to claim 3, wherein:

8. The communication device according to claim 1 , wherein the transmitting means transmits a cyclic prefix based on the M number of numerical sequences immediately before or after the M number of numerical sequences indicated by the fourth vector.

9. the storage means stores a plurality of pieces of processing information in which at least one of the time information and the frequency information is different, First processing information among the plurality of pieces of processing information is used to transmit first transmission data; The communication device according to claim 1 , wherein second processing information of the plurality of pieces of processing information is used for transmitting second transmission data.

10. the storage means stores a plurality of pieces of processing information in which the time information and the frequency information are the same but the element information is different, First processing information among the plurality of pieces of processing information is used to transmit first transmission data; The communication device according to claim 1 , wherein second processing information of the plurality of pieces of processing information is used for transmitting second transmission data.

11. The communication device according to claim 10 , wherein the N elements of the M-dimensional vector indicated by the first processing information are the same as the N elements of the M-dimensional vector indicated by the second processing information.

12. The communication device according to claim 10 , wherein the N elements of the M-dimensional vector indicated by the first processing information do not include the N elements of the M-dimensional vector indicated by the second processing information.

13. When transmitting the first transmission data and the second transmission data, the mapping means generates the first vector based on the first transmission data and the first vector based on the second transmission data; the first conversion means converts the first vector based on the first transmission data into the second vector based on the first transmission data, and converts the first vector based on the second transmission data into the second vector based on the second transmission data; the processing means generates the third vector corresponding to the n time based on the first transmission data from the second vector based on the first transmission data in accordance with the element information included in the first processing information, and generates the third vector corresponding to the n time based on the second transmission data from the second vector based on the second transmission data in accordance with the element information included in the second processing information; 11. The communication device according to claim 10, wherein the second conversion means converts the fifth vector corresponding to the n time into the fourth vector corresponding to the n time by multiplying the fifth vector corresponding to the n time obtained by adding the third vector corresponding to the n time based on the first transmission data and the third vector corresponding to the n time based on the second transmission data by the second regular matrix.

14. The communication device according to claim 13 , wherein the first transmission data and the second transmission data are transmitted to different devices.

15. The communication device according to claim 13 , wherein the first transmission data and the second transmission data are transmitted to the same device.

16. A communication device, a storage means for storing processing information including time information indicating N times from a first time to an Nth time, frequency information indicating a frequency at each of the N times indicated by the time information, element information indicating a one-to-one correspondence between the N times indicated by the time information and N elements of an N-dimensional vector, and a one-to-one correspondence between the N times indicated by the time information and N elements of an M-dimensional vector, wherein N is an integer equal to or greater than 2 and M is an integer equal to or greater than N; a receiving means for receiving, from an n-th time (n is an integer from 1 to N) indicated by the time information, a signal having a frequency at the n-th time indicated by the frequency information, and outputting an M-dimensional fourth vector corresponding to the n-th time including M numerical sequence; a first conversion means for converting the fourth vector corresponding to the n time instant into an M-dimensional third vector corresponding to the n time instant by multiplying the fourth vector corresponding to the n time instant by a first regular matrix having a size M; a processing means for performing a process of generating an N-dimensional second vector from the third vector corresponding to each of the N time points according to the element information, wherein a value of an element of the second vector corresponding to the n-th time point is the same as a value of an element of the third vector corresponding to the n-th time point; second conversion means for converting the second vector into a first vector by multiplying the second vector by a second regular matrix of size N; a determination means for determining received data based on the first vector; A communication device comprising:

17. The communication device according to claim 16 , wherein the time information and the frequency information are set so that reception periods of signals received at the same frequency from the first time to the Nth time do not overlap.

18. the received data is P-bit data, the determination means determines the received data based on the position of the element with the largest absolute value among the N elements of the first vector; The value of P is log ２ 17. The communication device of claim 16, wherein the number of the plurality of nodes is N or less.

19. The received data is (P+Q)-bit data, the determining means determines P-bit data of the (P+Q) bits based on the position of an element having a maximum absolute value among the N elements of the first vector, and determines Q-bit data of the (P+Q) bits based on the value of the element having the maximum absolute value; The value of P is log ２ 17. The communication device of claim 16, wherein the number of the plurality of nodes is N or less.

20. the received data is P-bit data, the determining means determines the P-bit data based on a combination of positions of the top γ elements in descending order of absolute values ​​of the N elements of the first vector; The value of γ is 2 or more, The value of P is log ２ ( Ｎ C γ 17. The communication device of claim 16, wherein:

21. The received data is (P+Q)-bit data, the determination means determines data of P bits among the (P+Q) bits based on a combination of positions of the most significant γ elements in descending order of absolute values ​​of the N elements of the first vector, and determines data of Q bits among the (P+Q) bits based on values ​​of the most significant γ elements; The value of γ is 2 or more, The value of P is log ２ ( Ｎ C γ 17. The communication device of claim 16, wherein:

22. the storage means stores a plurality of pieces of processing information in which at least one of the time information and the frequency information is different, First processing information among the plurality of pieces of processing information is used to receive first reception data; The communication device according to claim 16 , wherein second processing information of the plurality of pieces of processing information is used to receive second received data.

23. the storage means stores a plurality of pieces of processing information in which the time information and the frequency information are the same but the element information is different, First processing information among the plurality of pieces of processing information is used to receive first reception data; The communication device according to claim 16 , wherein second processing information of the plurality of pieces of processing information is used to receive second received data.

24. When the first received data and the second received data are received, the processing means generates the second vector corresponding to the first received data from the third vector corresponding to each of the N time points in accordance with the element information included in the first processing information, and generates the second vector corresponding to the second received data from the third vector corresponding to each of the N time points in accordance with the element information included in the second processing information; the second conversion means converts the second vector corresponding to the first received data into the first vector corresponding to the first received data, and converts the second vector corresponding to the second received data into the first vector corresponding to the second received data, using the second regular matrix; 24. The communication device according to claim 23, wherein the determination means determines the first received data based on the first vector corresponding to the first received data, and determines the second received data based on the second vector corresponding to the second received data.

25. The communication device according to claim 24 , wherein the first received data and the second received data are transmitted from different devices.

26. The communication device according to claim 24 , wherein the first received data and the second received data are transmitted from the same device.

27. A computer program product which, when executed on one or more processors of a device having said one or more processors, causes said device to function as a communications device according to any one of claims 1 to 26.

28. A communication method for a communication device having processing information including: time information indicating N times from a first time to an Nth time; frequency information indicating a frequency at each of the N times indicated by the time information; a one-to-one correspondence between the N times indicated by the time information and N elements of an N-dimensional vector; and element information indicating a one-to-one correspondence between the N times indicated by the time information and N elements of an M-dimensional vector, N is an integer equal to or greater than 2, and M is an integer equal to or greater than N, and the communication method includes: Mapping the transmit data into an N-dimensional first vector; transforming the first vector into an N-dimensional second vector by multiplying the first vector by a first regular matrix of size N; generating, based on the second vector, M-dimensional third vectors corresponding to the N time instants in accordance with the element information, wherein a value of an element of the third vector corresponding to an n-th time instant (n is an integer from 1 to N) is the same as a value of an element of the second vector corresponding to the n-th time instant, and a value of an element of the third vector corresponding to the n-th time instant that is different from the element corresponding to the n-th time instant is 0; multiplying the third vector corresponding to the n time by a second regular matrix of size M, thereby converting the third vector corresponding to the n time into an M-dimensional fourth vector corresponding to the n time; transmitting, from the n time instant, M numerical sequence numbers indicated by the fourth vector corresponding to the n time instant using a signal having a frequency at the n time instant indicated by the frequency information; A communication method, including:

29. A communication method for a communication device having processing information including: time information indicating N times from a first time to an Nth time; frequency information indicating a frequency at each of the N times indicated by the time information; element information indicating a one-to-one correspondence between the N times indicated by the time information and N elements of an N-dimensional vector; and element information indicating a one-to-one correspondence between the N times indicated by the time information and N elements of an M-dimensional vector, N is an integer equal to or greater than 2, and M is an integer equal to or greater than N, and the communication method includes: receiving a signal having a frequency at the nth time indicated by the frequency information from an nth time indicated by the time information (n is an integer from 1 to N), and outputting an M-dimensional fourth vector corresponding to the nth time including M numerical sequence; converting the fourth vector corresponding to the n time instant into an M-dimensional third vector corresponding to the n time instant by multiplying the fourth vector corresponding to the n time instant by a first regular matrix having a size M; generating an N-dimensional second vector from the third vector corresponding to each of the N time points according to the element information, wherein a value of an element of the second vector corresponding to the n time point is the same as a value of an element of the third vector corresponding to the n time point; transforming the second vector into a first vector by multiplying the second vector by a second regular matrix of size N; determining received data based on the first vector; A communication method, including:

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