JP5861558B2 - COMMUNICATION DEVICE AND COMMUNICATION METHOD - Google Patents

Description

  The present invention relates to a communication device and a communication method.

  In OFDM (Orthogonal Frequency-Division Multiplexing) communication, an input signal is subjected to subcarrier modulation, IFFT (Inverse Fast Fourier Transformation) is performed, and a baseband signal is generated. Therefore, when the number of subcarriers increases and the FFT (Fast Fourier Transformation) size increases, a baseband signal with a large peak is generated, and the PAPR (Peak-to-Average Power Ratio) ) Is high. As the PAPR increases, an amplifier having linearity in a wide range is required to transmit a signal without distortion. Therefore, techniques for reducing PAPR have been developed.

  In Patent Document 1, in order to reduce PAPR, the phase of the subcarrier modulation signal is controlled based on the optimum phase calculated by the sequential determination method before performing IFFT.

JP 2006-165781 A

  In OFDM communication, reducing PAPR is an issue. In Patent Document 1, it is necessary to perform iterative calculation processing in order to calculate the optimum phase for reducing the PAPR, and to control the phase for each subcarrier. Further, the technique disclosed in Patent Document 1 cannot control the degree of PAPR reduction.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to reduce PAPR and control the degree of reduction of PAPR in OFDM communication.

In order to achieve the above object, a communication device according to the first aspect of the present invention provides:
A communication device that communicates with other devices by orthogonal frequency division multiplex communication wireless communication,
Modulation means for modulating an input signal by a predetermined modulation method, assigning frequency components to subcarriers orthogonal to each other, and generating a subcarrier modulation signal;
A block diagonal matrix of a predetermined size, wherein the diagonal block is a matrix indicating an inverse discrete Fourier transform, and a block diagonal matrix having the same size as the inverse transform matrix, A plurality of the inverse transformation matrices having the same or different at least one of the diagonal blocks, and the size of the diagonal block using a transformation matrix whose block is a matrix indicating discrete Fourier transform Arithmetic means for generating arithmetic data by multiplying the subcarrier modulation signal by an arithmetic result obtained by multiplying a predetermined number of the transform matrices, which are the same or different from each other, and one less than the inverse transform matrix. When,
Synthesis means for generating a baseband signal based on data obtained by synthesizing the operation data;
Transmitting means for generating and transmitting a transmission signal from the baseband signal;
It is characterized by providing.

The communication device according to the second aspect of the present invention is:
Receiving means for receiving a transmission signal and generating a baseband signal;
Series-parallel means for serial-parallel conversion of the baseband signal to generate a parallel signal;
A block diagonal matrix having a predetermined size, wherein the diagonal block is a matrix indicating a predetermined discrete Fourier transform, and a block diagonal matrix having the same size as the reception side conversion matrix, A plurality of reception-side transformation matrices, each of which has the same or different at least one size of the diagonal blocks, using a reception-side inverse transformation matrix whose diagonal block represents a predetermined inverse discrete Fourier transform. And the parallel result obtained by multiplying the reception block inverse matrixes in a predetermined order by the number of the reception block inverse matrixes, which is one or less than the reception block transformation matrix, having the same or different at least one of the diagonal blocks. Inverse operation means for multiplying the signal to generate a subcarrier modulation signal;
Demodulation means for demodulating the subcarrier modulation signal by a predetermined demodulation method;
It is characterized by providing.

The communication method according to the third aspect of the present invention is:
A modulation step of modulating an input signal with a predetermined modulation method, assigning frequency components to subcarriers orthogonal to each other, and generating a subcarrier modulation signal;
A block diagonal matrix of a predetermined size, wherein the diagonal block is a matrix indicating an inverse discrete Fourier transform, and a block diagonal matrix having the same size as the inverse transform matrix, A plurality of the inverse transformation matrices having the same or different at least one of the diagonal blocks, and the size of the diagonal block using a transformation matrix whose block is a matrix indicating discrete Fourier transform An operation step of generating operation data by multiplying an operation result obtained by multiplying a predetermined number of the transform matrices, which are the same or different from each other, by one less than the inverse transform matrix, by the subcarrier modulation signal. When,
A synthesis step of generating a baseband signal based on data obtained by synthesizing the operation data;
A transmission step of generating and transmitting a transmission signal from the baseband signal;
It is characterized by providing.

A communication method according to a fourth aspect of the present invention is:
A reception step of receiving a transmission signal and generating a baseband signal;
A serial-parallel step of serial-parallel conversion of the baseband signal to generate a parallel signal;
A block diagonal matrix having a predetermined size, wherein the diagonal block is a matrix indicating a predetermined discrete Fourier transform, and a block diagonal matrix having the same size as the reception side conversion matrix, A plurality of reception-side transformation matrices, each of which has the same or different at least one size of the diagonal blocks, using a reception-side inverse transformation matrix whose diagonal block represents a predetermined inverse discrete Fourier transform. And the parallel result obtained by multiplying the reception block inverse matrixes in a predetermined order by the number of the reception block inverse matrixes, which is one or less than the reception block transformation matrix, having the same or different at least one of the diagonal blocks. An inverse operation step of multiplying the signal to generate a subcarrier modulation signal;
A demodulation step for demodulating the subcarrier modulation signal by a predetermined demodulation method;
It is characterized by providing.

  According to the present invention, it is possible to reduce PAPR and further control the degree of PAPR reduction in OFDM communication.

It is a block diagram which shows the structural example of the communication apparatus which concerns on embodiment of this invention. It is a block diagram which shows the example of a different structure of the communication apparatus which concerns on embodiment. It is a figure which shows the example of the arithmetic processing which the calculating part which concerns on embodiment performs. It is a figure which shows the example of the arithmetic processing which the calculating part which concerns on embodiment performs. It is a flowchart which shows an example of the operation | movement of transmission control which the communication apparatus which concerns on embodiment performs. It is a flowchart which shows an example of the operation | movement of reception control which the communication apparatus which concerns on embodiment performs. It is a figure which shows the characteristic of simulated CCDF. It is a figure which shows the characteristic of simulated BER. It is a figure which shows the characteristic of simulated CCDF. It is a figure which shows the characteristic of simulated CCDF. It is a figure which shows the characteristic of simulated CCDF.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or equivalent parts are denoted by the same reference numerals.

  FIG. 1 is a block diagram illustrating a configuration example of a communication device according to an embodiment of the present invention. The communication device 1 communicates with other devices by OFDM (Orthogonal Frequency-Division Multiplexing) wireless communication. The communication device 1 includes an antenna 10, a modulation unit 11, a serial / parallel conversion unit 12, a calculation unit 13, a synthesis unit 14, a transmission unit 15, and a controller 20.

  The controller 20 includes a CPU (Central Processing Unit) 21, a RAM (Random Access Memory) 23, and a ROM (Read-Only Memory) 24. In order to avoid complication and to facilitate understanding, signal lines from the controller 20 to each part are omitted, but the controller 20 is connected to each part of the communication device 1 via an I / O (Input / Output) 22. The start and end of these processes and the control of the process contents are performed.

  In the RAM 23, for example, data for generating a transmission frame is stored. The ROM 24 stores a control program for the controller 20 to control the operation of the communication device 1. The controller 20 controls the communication device 1 based on the control program.

  FIG. 2 is a block diagram illustrating a different configuration example of the communication device according to the embodiment. In order to provide the above-described communication device 1 with a reception function, the communication device 1 shown in FIG. 2 further includes a demodulation unit 31, a parallel / serial conversion unit 32, an inverse operation unit 33, a serial / parallel conversion unit 34, a reception unit 35, and a transmission / reception switching unit. 36. A communication method performed by the communication device 1 using the communication device 1 shown in FIG. 2 having a transmission function and a reception function will be described below.

  The modulation unit 11 modulates the input signal using a predetermined modulation method, generates a modulation signal, and sends the modulated signal to the serial-parallel conversion unit 12. For example, QPSK (Quadrature Phase-Shift Keying) is used as the modulation method. The serial / parallel conversion unit 12 performs serial / parallel conversion on the modulated signal, assigns the frequency components to subcarriers orthogonal to each other, and generates a subcarrier modulated signal. Then, the subcarrier modulation signal is sent to the calculation unit 13.

  The calculation unit 13 is a block diagonal matrix of a predetermined size, and the diagonal block is an inverse transformation matrix in which the diagonal block indicates an IDFT (Inverse Discrete Fourier Transformation), A plurality of inverse transformation matrices having the same size or different at least one of them are prepared. A block diagonal matrix is obtained by dividing a square matrix into a predetermined number of sub-matrices having the same number of rows and columns, and elements other than diagonal blocks that are sub-matrices located at the diagonal of the square matrix. It is a matrix with a value of 0. The block diagonal matrix used in the present invention includes a case where a small matrix matches a square matrix before division, that is, an inverse transformation matrix may match a matrix indicating IDFT.

  The calculation unit 13 is a block diagonal matrix having the same size as the inverse transformation matrix, and the diagonal block is a matrix indicating DFT (Discrete Fourier Transformation). A number of transformation matrices that is one less than the inverse transformation matrix and having the same size or different at least one of them is prepared. Similar to the inverse transformation matrix, the transformation matrix may match a matrix indicating DFT.

  The calculation unit 13 generates calculation data by multiplying the calculation result obtained by multiplying the inverse transformation matrix and the conversion matrix in a predetermined order by the subcarrier modulation signal, and sends the calculation data to the synthesis unit 14.

  The calculation unit 13 performs calculation processing as follows, for example. Here, the display format of the matrix operation is defined. The Kronecker product of the matrix A and the matrix B expressed by the following equation (1) is expressed by the following equation (2).

  From the above equations (1) and (2), each element of the Kronecker product of the matrix A and the matrix B is expressed by the following equation (3).

The numbers of rows and columns of the block diagonal matrix is N, and the number of rows and the number of columns in the matrix indicating the IDFT or DFT and N _i, N is expressed by the following equation (4). In the equation, k _i is a natural number. i is a number for uniquely specifying the inverse transformation matrix and the transformation matrix.

The inverse transformation matrix Kronecker product of matrices F _i ^-1 showing an IDFT below (5) unit matrix I _i and the number of rows and columns is the number of rows and columns is k _i represented by the formula is N _i The transformation matrix is represented by a Kronecker product of a unit matrix I _i having the number of rows and columns k _i and a matrix F _i indicating a DFT having the number of rows and columns N _i . The inverse transformation matrix G _i ⁻¹ and the transformation matrix G _i are expressed by the following equation (6).

For example, the arithmetic unit 13 alternately multiplies the inverse transformation matrix and the transformation matrix, each having a different value of k _i , so that the computation result does not become a unit matrix or a matrix indicating IDFT with N rows and columns. Calculation data is generated by multiplying the calculation result by the subcarrier modulation signal. Assuming that the subcarrier modulation signal is d and m number of inverse transformation matrices and transformation matrices are prepared, the operation data u is expressed by the following equation (7).

3 and 4 are diagrams illustrating an example of the arithmetic processing performed by the arithmetic unit according to the embodiment. FIG. 3A is a signal point arrangement diagram of the subcarrier modulation signal. The calculation unit 13 sets N = 2048, k ₁ = 512, inverse transformation matrix G ₁ ⁻¹ , k ₂ = 64 transformation matrix G ₂ , k ₃ = 128 inverse transformation matrix G ₃ ⁻¹ , k ₄ = 8 transformation matrix G ₄ , k ₅ = 1 inverse transformation matrix G ₅ ⁻¹ , k ₆ = 2 transformation matrix G ₆ , k ₇ = 16 inverse transformation matrix G ₇ ⁻¹ To do. 3B is a result of multiplying G ₁ ⁻¹ by a subcarrier modulation signal, FIG. 3C is a result of multiplying G ₁ ⁻¹ · G ₂ by a subcarrier modulation signal, and FIG. As a result of multiplying ₁ ⁻¹ · G ₂ · G ₃ ⁻¹ by the subcarrier modulation signal, FIG. 4A is obtained by multiplying G ₁ ⁻¹ · G ₂ · G ₃ ⁻¹ · G ₄ by the subcarrier modulation signal. As a result, FIG. 4B shows the result of multiplying G ₁ ⁻¹ · G ₂ · G ₃ ⁻¹ · G ₄ · G ₅ ⁻¹ by the subcarrier modulation signal, and FIG. 4C shows G ₁ ⁻¹ · G. As a result of multiplying ₂ · G ₃ ⁻¹ · G ₄ · G ₅ ⁻¹ · G ₆ by the subcarrier modulation signal, FIG. 4 (d) shows G ₁ ⁻¹ · G ₂ · G ₃ ⁻¹ · G ₄ · G. _This is operation data generated by multiplying ₅ ⁻¹ · G ₆ · G ₇ ⁻¹ by the subcarrier modulation signal.

  It can be seen that the signal point constellation diagram of the operation data generated by performing the above-described arithmetic operation is more dispersed than the signal point constellation diagram of the subcarrier modulation signal shown in FIG. Thereby, PAPR (Peak-to-Average Power Ratio) can be reduced.

  The synthesizer 14 synthesizes the operation data and generates a baseband signal based on the synthesized data. The synthesizer 14 sends the baseband signal to the transmitter 15. The transmission unit 15 generates a transmission signal from the baseband signal, and sends the transmission signal to another device via the transmission / reception switching unit 36 and the antenna 10.

  FIG. 5 is a flowchart illustrating an example of a transmission control operation performed by the communication device according to the embodiment. The modulation unit 11 modulates the input signal with a predetermined modulation method to generate a modulation signal, and the serial / parallel conversion unit 12 performs serial / parallel conversion on the modulation signal and assigns the frequency components to subcarriers orthogonal to each other. A modulation signal is generated (step S110).

  The calculation unit 13 generates calculation data by multiplying the calculation result obtained by multiplying the inverse transformation matrix and the conversion matrix in a predetermined order by the subcarrier modulation signal (step S120). The synthesizer 14 synthesizes the operation data and generates a baseband signal based on the synthesized data (step S130). The transmission unit 15 generates a transmission signal from the baseband signal, and transmits the transmission signal to another device via the transmission / reception switching unit 36 and the antenna 10 (step S140). When the transmission process in step S140 is completed, the process ends.

  Processing on the receiving side will be described below. The receiving unit 35 receives a transmission signal via the antenna 10 and the transmission / reception switching unit 36, generates a baseband signal, and sends the baseband signal to the serial-parallel conversion unit 34. The serial / parallel converter 34 performs serial / parallel conversion on the baseband signal, generates a parallel signal, and sends the parallel signal to the inverse operation unit 33.

  The inverse operation unit 33 is a reception-side transformation matrix that is a block diagonal matrix having a predetermined size, where the diagonal blocks indicate a predetermined DFT, and the sizes of the diagonal blocks are the same or at least A plurality of receiving side transformation matrices, each one of which is different, are prepared. The matrix indicating the predetermined DFT is an inverse matrix of a matrix indicating IDFT, which is a diagonal block of the inverse conversion matrix used in the transmission side arithmetic unit 13 corresponding to the reception side conversion matrix, and the reception side conversion matrix is Each is an inverse matrix of each inverse transform matrix used in the computation unit 13 on the transmission side.

  The inverse operation unit 33 is a block diagonal matrix having the same size as the reception side transformation matrix, and the reception side inverse transformation matrix in which the diagonal block indicates a predetermined IDFT, and the size of the diagonal block Are equal to each other or at least one of them is different from the reception-side transformation matrix, which is one less than the reception-side transformation matrices. The matrix indicating the predetermined IDFT is an inverse matrix of a matrix indicating DFT, which is a diagonal block of the conversion matrix used in the transmission-side arithmetic unit 13 and corresponds to the reception-side inverse conversion matrix. Are the inverse matrices of the transformation matrices used in the computation unit 13 on the transmission side.

  The inverse operation unit 33 generates a subcarrier modulation signal by multiplying the operation result obtained by multiplying the reception-side transformation matrix and the reception-side inverse transformation matrix in a predetermined order by the parallel signal. The inverse computing unit 33 is a reverse side of the order of multiplying the inverse transformation matrix and the transformation matrix when the computation unit 13 on the transmission side generates computation data, The parallel signal is multiplied by the operation result obtained by multiplying the receiving side inverse transformation matrix which is the inverse matrix of the transformation matrix. When the parallel signal is r, the parallel signal r matches the operation data u. From the above equation (7), s, which is the result of multiplying the calculation result by the parallel signal, matches the subcarrier modulation signal d as represented by the following equation (8). The inverse operation unit 33 sends the subcarrier modulation signal to the parallel / serial conversion unit 32.

  The parallel / serial converter 32 performs parallel / serial conversion on the subcarrier modulation signal, generates a serial signal, and sends the serial signal to the demodulator 31. The demodulator 31 demodulates the serial signal using a predetermined demodulation method. For example, the demodulator 31 performs QPSK demodulation of the serial signal. Thus, the input signal modulated by the modulation unit 11 can be demodulated by the demodulation unit 31 and output.

  FIG. 6 is a flowchart illustrating an example of a reception control operation performed by the communication device according to the embodiment. The receiving unit 35 receives a transmission signal via the antenna 10 and the transmission / reception switching unit 36, and generates a baseband signal (step S210). The serial / parallel converter 34 performs serial / parallel conversion on the baseband signal to generate a parallel signal (step S220).

  The inverse operation unit 33 multiplies the operation result obtained by multiplying the reception-side transformation matrix and the reception-side inverse transformation matrix in a predetermined order by the parallel signal to generate a subcarrier modulation signal (step S230). The parallel / serial converter 32 performs parallel / serial conversion on the subcarrier modulation signal to generate a serial signal, and the demodulator 31 demodulates the serial signal using a predetermined demodulation method (step S240). When the demodulation process in step S240 is completed, the process ends.

  As described above, according to the communication device 1 according to the embodiment of the present invention, a baseband signal is generated by synthesizing operation data generated by performing a predetermined operation on a subcarrier modulation signal in an OFDM communication system. By doing so, it becomes possible to reduce PAPR. As will be described later, it is possible to reduce PAPR and control the degree of reduction of PAPR.

(Concrete example)
Next, effects of the invention according to the embodiment will be described by simulation. The modulation method is QPSK, N = 2048, and the characteristics of PAPR CCDF (Complementary Cumulative Distribution Function), that is, the probability of occurrence of PAPR, are compared. FIG. 7 is a diagram showing the characteristics of the simulated CCDF. The horizontal axis is PAPR (unit: dB), and the vertical axis is PAPR CCDF. The prior art is a method of generating a baseband signal by performing IFFT of a subcarrier modulation signal with an FFT size of 2048 without adding the above-described calculation. In the present embodiment, the subcarrier modulation signal is applied to G ₁ ⁻¹ · G ₂ · G ₃ ⁻¹ · G ₄ · G ₅ ⁻¹ · G ₆ · G ₇ ⁻¹ as in FIG. Operation data was generated by multiplication.

  The CCDF characteristic of the PAPR of the prior art is a thick solid line graph, and the CCDF characteristic of the invention according to the present embodiment is a thin solid line graph. In the range shown in the figure, the PAPR of the invention according to the present embodiment is reduced as compared with the prior art. The PAPR when the simulation is performed using the same signal in which the phase of each element of the subcarrier modulation signal is the same as the input signal is 33.1 dB in the prior art, whereas the PAPR of the invention according to the present embodiment is The PAPR was greatly improved to 3.01 dB.

  Similarly, a simulation for BER was performed. FIG. 8 is a diagram showing simulated BER characteristics. The horizontal axis represents Eb / No (Energy per Bit to NOise power spectral density ratio), and the vertical axis represents BER. The unit of Eb / No is dB. The BER of the prior art is a graph in which plot points are represented by squares, and the BER of the invention according to the present embodiment is a graph in which plot points are represented by triangles. It can be seen that the BER of the prior art and the invention according to the present embodiment are substantially the same. Similar results were obtained even when the inverse transformation matrix and transformation matrix used to generate the operation data were changed.

  9, FIG. 10, and FIG. 11 are diagrams showing the characteristics of the simulated CCDF. In this embodiment, the simulation is performed by changing the inverse transformation matrix and the transformation matrix, assuming that the modulation method is QPSK and N = 2048. In each figure, the CCDF characteristic of the PAPR of the prior art is a thick solid line graph, and the CCDF characteristic of the invention according to the present embodiment is a thin solid line graph.

9, in this _embodiment, k 1 = 512 inverse transformation matrix _G ¹ -1 _a, k 2 = 256 conversion matrix _{G 2,} k 3 = 128 inverse transformation matrix _G ³ -1 is, k ₄ = 2 is the transformation matrix _{G 4, k} 5 = 1 inverse transformation matrix _G ⁵ -1 _is, using an inverse transformation matrix _G ^{7 -1} a _k 6 = a 4 transformation matrix _{G 6,} k 7 = 32 , G ₁ ⁻¹ • G ₂ • G ₃ ⁻¹ • G ₄ • G ₅ ⁻¹ • G ₆ • G ₇ ⁻¹ are multiplied by the subcarrier modulation signal to generate operation data. When the simulation was performed using the same signal as an input signal, the PAPR of the invention according to the present embodiment was 3.01 dB.

10, in this _embodiment, with k 1 = 1024 inverse transformation matrix _G ¹ -1 _{a, k} 2 = 2 a is the transformation matrix _{G 2, k} 3 = inverse transformation matrix _G ^{3 -1} 1 , G ₁ ⁻¹ · G ₂ · G ₃ ⁻¹ are multiplied by the subcarrier modulation signal to generate operation data. The PAPR of the invention according to the present embodiment when a simulation was performed using the same signal as an input signal was 6.02 dB.

11, in this _embodiment, k 1 = 1024 inverse transformation matrix _G ¹ -1 _a, k 2 = 512 a transformation matrix _{G 2,} k 3 = inverse transformation matrix _G ³ -1 is 256, k using ₄ = 128 a is the transformation matrix _{G 4,} k 5 = 64 inverse transformation matrix _G ⁵ -1 _is, k 6 = 32 a is a transformation matrix _{G 6, k} 7 = inverse transformation matrix _G ^{7 -1} 1 , G ₁ ⁻¹ • G ₂ • G ₃ ⁻¹ • G ₄ • G ₅ ⁻¹ • G ₆ • G ₇ ⁻¹ are multiplied by the subcarrier modulation signal to generate operation data.

  9 and 10, the PAPR is reduced as compared with the prior art, but FIG. 11 shows the PAPR characteristics almost the same as those of the prior art. Therefore, it can be seen that the PAPR changes based on the inverse transformation matrix, the transformation matrix, and the order of multiplication of the inverse transformation matrix and the transformation matrix. What is necessary is just to comprise so that calculation data may be produced | generated based on the order which multiplies a suitable inverse transformation matrix, a transformation matrix, and an inverse transformation matrix, and a transformation matrix.

  From the above simulation, it has been found that PAPR can be reduced by synthesizing calculation data generated by performing a predetermined calculation on the subcarrier modulation signal to generate a baseband signal. It was also found that the degree of PAPR reduction can be controlled by changing the inverse transformation matrix, the transformation matrix, and the order of multiplication of the inverse transformation matrix and the transformation matrix.

  The embodiment of the present invention is not limited to the above-described embodiment. The modulation method of the modulation unit 11 is not limited to QPSK, and PSK (Phase Shift Keying) other than QPSK, Quadrature Amplitude Modulation (QAM), or the like can be used. The order of the modulation unit 11 and the serial / parallel conversion unit 12 may be changed, the input signal may be serial / parallel converted and assigned to the subcarrier signal, and each data of the parallel signal may be modulated by a predetermined modulation method. In that case, the receiving side performs demodulation processing by changing the order of the demodulator 31 and the parallel-serial converter 32.

The arithmetic processing performed by the arithmetic unit 13 is not limited to the above-described embodiment. For example, G ₁ ⁻¹ · G ₂ ⁻¹ · G ₃ may be multiplied by the subcarrier modulation signal to generate operation data without alternately calculating the inverse transformation matrix and the transformation matrix. In this case, the inverse operation unit 33 multiplies G ₃ ⁻¹ · G ₂ · G ₁ by the parallel signal to generate a subcarrier modulation signal. Further, the arithmetic unit 13 uses, for example, a plurality of inverse transformation matrices or transformation matrices having the same diagonal block size, and multiplies G ₁ ⁻¹ · G ₁ ⁻¹ · G ₂ by a subcarrier modulation signal, for example. Data may be generated. In this case, the inverse operation unit 33 multiplies G ₂ ⁻¹ · G ₁ · G ₁ by the parallel signal to generate a subcarrier modulation signal.

1 communication equipment
10 Antenna
11 Modulator
12 Series-parallel converter
13 Calculation unit
14 Synthesizer
15 Transmitter
20 controller
21 CPU
22 I / O
23 RAM
24 ROM
31 Demodulator
32 Parallel to serial converter
33 Inverse operation part
34 Series-parallel converter
35 Receiver
36 Transmission / reception switching unit

Claims (4)

A communication device that communicates with other devices by orthogonal frequency division multiplex communication wireless communication,
Modulation means for modulating an input signal by a predetermined modulation method, assigning frequency components to subcarriers orthogonal to each other, and generating a subcarrier modulation signal;
A block diagonal matrix of a predetermined size, wherein the diagonal block is a matrix indicating an inverse discrete Fourier transform, and a block diagonal matrix having the same size as the inverse transform matrix, A plurality of the inverse transformation matrices having the same or different at least one of the diagonal blocks, and the size of the diagonal block using a transformation matrix whose block is a matrix indicating discrete Fourier transform Arithmetic means for generating arithmetic data by multiplying the subcarrier modulation signal by an arithmetic result obtained by multiplying a predetermined number of the transform matrices, which are the same or different from each other, and one less than the inverse transform matrix. When,
Synthesis means for generating a baseband signal based on data obtained by synthesizing the operation data;
Transmitting means for generating and transmitting a transmission signal from the baseband signal;
A communication device comprising: A communication device that communicates with other devices by orthogonal frequency division multiplex communication wireless communication,
Receiving means for receiving a transmission signal and generating a baseband signal;
Series-parallel means for serial-parallel conversion of the baseband signal to generate a parallel signal;
A block diagonal matrix having a predetermined size, wherein the diagonal block is a matrix indicating a predetermined discrete Fourier transform, and a block diagonal matrix having the same size as the reception side conversion matrix, A plurality of reception-side transformation matrices, each of which has the same or different at least one size of the diagonal blocks, using a reception-side inverse transformation matrix whose diagonal block represents a predetermined inverse discrete Fourier transform. And the parallel result obtained by multiplying the reception block inverse matrixes in a predetermined order by the number of the reception block inverse matrixes, which is one or less than the reception block transformation matrix, having the same or different at least one of the diagonal blocks. Inverse operation means for multiplying the signal to generate a subcarrier modulation signal;
Demodulation means for demodulating the subcarrier modulation signal by a predetermined demodulation method;
A communication device comprising: A communication method performed by a communication device that communicates with other devices by wireless communication of an orthogonal frequency division multiplex communication method,
A modulation step of modulating an input signal with a predetermined modulation method, assigning frequency components to subcarriers orthogonal to each other, and generating a subcarrier modulation signal;
A block diagonal matrix of a predetermined size, wherein the diagonal block is a matrix indicating an inverse discrete Fourier transform, and a block diagonal matrix having the same size as the inverse transform matrix, A plurality of the inverse transformation matrices having the same or different at least one of the diagonal blocks, and the size of the diagonal block using a transformation matrix whose block is a matrix indicating discrete Fourier transform An operation step of generating operation data by multiplying an operation result obtained by multiplying a predetermined number of the transform matrices, which are the same or different from each other, by one less than the inverse transform matrix, by the subcarrier modulation signal. When,
A synthesis step of generating a baseband signal based on data obtained by synthesizing the operation data;
A transmission step of generating and transmitting a transmission signal from the baseband signal;
A communication method comprising: A communication method performed by a communication device that communicates with other devices by wireless communication of an orthogonal frequency division multiplex communication method,
A reception step of receiving a transmission signal and generating a baseband signal;
A serial-parallel step of serial-parallel conversion of the baseband signal to generate a parallel signal;
A block diagonal matrix having a predetermined size, wherein the diagonal block is a matrix indicating a predetermined discrete Fourier transform, and a block diagonal matrix having the same size as the reception side conversion matrix, A plurality of reception-side transformation matrices, each of which has the same or different at least one size of the diagonal blocks, using a reception-side inverse transformation matrix whose diagonal block represents a predetermined inverse discrete Fourier transform. And the parallel result obtained by multiplying the reception block inverse matrixes in a predetermined order by the number of the reception block inverse matrixes, which is one or less than the reception block transformation matrix, having the same or different at least one of the diagonal blocks. An inverse operation step of multiplying the signal to generate a subcarrier modulation signal;
A demodulation step for demodulating the subcarrier modulation signal by a predetermined demodulation method;
A communication method comprising:

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