JP5897651B2 - COMMUNICATION METHOD, COMMUNICATION DEVICE, AND BAND SYNTHESIS CIRCUIT - Google Patents

Description

  The present invention relates to a communication apparatus used for wireless communication or wired communication, in which a plurality of different users effectively use a limited frequency band, and a signal transmitted by dividing the frequency band from the transmission apparatus is received by the reception apparatus. The present invention relates to a communication method, a communication apparatus, and a band synthesis circuit that perform band synthesis and perform demodulation processing.

FIG. 5 shows a configuration example of a conventional communication apparatus (see Non-Patent Document 1). FIG. 5 (a) shows a transmitting apparatus, and FIG. 5 (b) shows a receiving apparatus.
In FIG. 5 (a), the transmission apparatus includes a modulator 1, a root roll-off filter 2, and a band dividing circuit 10. The modulator 1 modulates a data signal to be transmitted by a modulation method such as QPSK, and inputs a single carrier modulation signal whose waveform is shaped via a root roll-off filter 2 to the band dividing circuit 10.

The band division circuit 10 includes a series-parallel conversion circuit 12, an FFT (Fast Fourier Transform) circuit 13, division filters 14 _{1 to} 14 _N (N is an integer of 2 or more), a frequency shifter 15 ₁ to 15 _N , an addition circuit 16, and an IFFT. (Fast Inverse Fourier Transform) A circuit 17, a parallel / serial converter circuit 18, and a D / A converter 19 are provided, and a band of a single carrier modulation signal is divided into N, and distributed and transmitted on the frequency axis. An example in which the band of the single carrier modulation signal is divided into three (N = 3) is shown in FIG.

The single carrier modulation signal input to the band dividing circuit 10 is serial-parallel converted and fast Fourier transformed by the FFT circuit 13 to convert from a time domain signal to a frequency domain signal (FIG. 6A). Each of the division filters 14 _{1 to} 14 _N multiplies a single carrier modulation signal converted into the frequency domain by a filter coefficient for dividing the signal band indicated by the broken line in FIG. A sub-modulated signal is generated. The frequency shifters 15 ₁ to 15 _N disperse and arrange the sub-modulated signals in a desired band on the frequency axis, and add them by the adder circuit 16 to generate sub-modulated signals that are dispersed and arranged (FIG. 6 ( c)). The sub-modulated signal after the distributed arrangement is converted from a frequency domain signal to a time domain signal by high-speed inverse Fourier transform in the IFFT circuit 17, and converted into a transmission signal by parallel-serial conversion and D / A conversion.

In FIG. 5 (b), the receiving device includes a band synthesis circuit 20 and a demodulator 6. The band synthesis circuit 20 includes an A / D converter 21, a serial-parallel conversion circuit 22, an FFT circuit 23, extraction filters 24 _{1 to} 24 _N , frequency shifters 25 _{1 to} 25 _N , an adder circuit 26, an IFFT circuit 27, and parallel-serial conversion. The circuit 28 is configured to synthesize a sub-modulated signal whose band is divided into N into a single carrier modulated signal before division. An example of synthesizing a single carrier modulation signal whose band is divided into three (N = 3) is shown in FIG.

The received signal input to the band synthesizing circuit 20 is A / D converted and serial-parallel converted, and fast Fourier transformed by the FFT circuit 23 to convert the time domain signal to the frequency domain received signal (FIG. 7 (a)). . Each of the extraction filters 24 _{1 to} 24 _N multiplies the reception signal converted into the frequency domain by a filter coefficient indicated by a broken line in FIG. Is extracted (FIG. 7 (c)). The frequency shifters 25 _{1 to} 25 _N return the extracted sub-modulated signal to the band before being frequency-shifted on the transmission side, and add them by the adding circuit 26 to generate a synthesized modulated signal (FIG. 7 ( d)). The combined modulation signal is converted from a frequency domain signal to a time domain signal by high-speed inverse Fourier transform in the IFFT circuit 27, and is subjected to parallel-serial conversion and output. The demodulator 6 demodulates the single carrier modulation signal output from the band synthesis circuit 20 and restores the data signal transmitted from the transmission device.

  By using such a transmission device and reception device, each sub-modulation signal generated by dividing the occupied band of the single carrier modulation signal can be distributed and arranged at any location on the frequency axis, so that it can be used by different users. A discontinuous free frequency band can be used effectively.

Abe, Yamashita, Kobayashi: "Proposal of spectrum-editing band-dispersed transmission to achieve high frequency utilization efficiency" IEICE Tech. Reports SAT2009-48, Dec 2009. Abe, Yamashita, Nakahira, Kobayashi: “Examination of frequency utilization efficiency improvement of existing satellite communication earth station by spectrum editing type band dispersion transmission” IEICE Technical Report SAT2010-67, Oct 2010.

On the transmission side, as shown in FIG. 6 (c), the filter coefficients of the division filters 14 _{1 to} 14 _N are designed so that each divided sub-modulated signal has a root roll-off characteristic. The characteristics of the division filters 14 ₁ and 14 _N are spectrum-edited asymmetrically.

When the roll-off rate of the single carrier modulation signal shown in FIG. 6A is α and the roll-off rate of the sub-modulation signal after division is β, the filters of the division filters 14 _{1 to} 14 _N shown in FIG. The coefficient Hd _k (f) is expressed by the following equation.

Where f is the frequency and f _{c k} is the center frequency of the divided sub-modulation signal k, B is the half-value width of the roll-off filter, and B _k is the half-value width of the sub-modulation signal k. The root roll-off function H (α, f, B) is expressed by the following equation.

On the receiving side, as shown in FIG. 7 (a), for the sub-modulated signal having the root roll-off characteristic with the roll-off rate β, as the extraction filters 24 _{1 to} 24 _N , the root roll-off with the same roll-off rate β is obtained. The filter is multiplied (FIG. 7 (b)). Thereby, as shown in FIG. 7C, the extracted sub-modulated signal has a full roll-off characteristic with a roll-off rate β.

  Each extracted sub-modulated signal is frequency-shifted to the band before division and synthesized. At this time, since the frequency is reduced by 6 dB in the adjacent sub-modulated signal, that is, the frequencies corresponding to the cutoff frequencies in the filter characteristics of the extraction filter are combined, as shown in FIG. A single carrier modulation signal having a full roll-off characteristic is obtained. Since this signal has a full roll-off characteristic, no intersymbol interference occurs, so that it can be demodulated by the demodulator 6 as it is.

  Here, only the band dividing circuit 10 and the band synthesizing circuit 20 shown in FIG. 5 are taken out, and this is used as a “band distribution adapter” to constitute a wireless communication system as shown in FIG. 8 (Non-Patent Document 2). That is, the wireless station A and the wireless station B insert a band dispersion adapter between the existing modem that transmits and receives an existing single carrier modulation signal and the antenna, and divide the output signal of the existing modem on the frequency axis by the band dispersion adapter. In addition, the frequency utilization efficiency is improved by distributing and transmitting in the unused band.

FIG. 9 shows a circuit configuration example of an existing modem and a bandwidth distribution adapter.
In FIG. 9, the transmission circuit of the existing modem is composed of a modulator 1, a root roll-off filter 2, and a D / A converter 3, and generates and outputs a band-limited single carrier modulated signal. The band dividing circuit 10 of the band distribution adapter has a configuration in which an A / D converter 11 is added to the configuration shown in FIG. 5A, performs A / D conversion and serial-parallel conversion on the output signal of the transmission circuit, and an FFT circuit. 13 converts the signal from the time domain to the frequency domain, generates a plurality of sub-modulated signals having root roll-off characteristics by the division filters 14 _{1 to} 14 _N, and distributes them in the unused band by the frequency shifters 15 ₁ to 15 _N The IFFT circuit 17 converts the signal into a time domain signal, performs parallel-serial conversion and D / A conversion, and outputs a transmission signal.

The band synthesizing circuit 20 of the band distribution adapter has a configuration in which a D / A converter 29 is added to the configuration shown in FIG. 5B, and receives a received signal having a route roll-off characteristic to perform A / D conversion and direct conversion. Parallel conversion is performed, the signal is converted from the time domain to the frequency domain by the FFT circuit 23, the sub-modulation signal having the full roll-off characteristic is extracted by the extraction filters 24 _{1 to} 24 _{N, and the} signal is divided by the frequency shifters 25 _{1 to} 25 _N Shift to the band of and combine. The synthesized signal is a single carrier modulation signal having a full roll-off characteristic. This is converted into a signal in the time domain by the IFFT circuit 27, subjected to parallel-serial conversion and D / A conversion, and input to the receiving circuit of the existing modem.

FIG. 10 shows the relationship between the band synthesis example in the band synthesis circuit 20 and the existing modem. FIGS. 10 (a) to 10 (d) are a reprint of FIGS. 7 (a) to 7 (d).
The reception circuit of the existing modem includes an A / D converter 4, a route roll-off filter 5 and a demodulator 6. The output signal of the band synthesis circuit 20 of the band dispersion adapter is A / D converted and the route roll-off filter 5. Is demodulated by the demodulator 6. However, the output signal of the band synthesizing circuit 20 already has a full roll-off characteristic as shown in FIG. Therefore, as shown in FIGS. 10 (e) and 10 (f), if the root roll-off filter 5 is further multiplied in the receiving circuit, the roll-off characteristic is not satisfied and intersymbol interference occurs. Therefore, there is a problem that the signal transmission characteristics deteriorate.

  It is an object of the present invention to provide a communication method, a communication apparatus, and a band synthesis circuit that can prevent the occurrence of intersymbol interference caused by band division of a single carrier modulation signal and improve signal transmission characteristics.

  According to a first aspect of the present invention, a modulation signal is input from a transmission circuit to a band division circuit, and the band division circuit generates sub modulation signals divided into a plurality of bands on the frequency axis from the modulation signal by a plurality of division filters, A transmission signal in which the sub-modulated signal is distributed at any location on the frequency axis is output, and the band synthesis circuit extracts each sub-modulated signal from the received signal corresponding to the transmitted signal using multiple extraction filters. A communication method that outputs a modulated signal that is synthesized by returning the signal band to the band before the distributed arrangement, and that demodulates the modulated signal output from the band synthesizing circuit by inputting it to the demodulator via the root roll-off filter of the receiving circuit The band synthesizer is a spectrum converting means for inputting the synthesized modulated signal, and the frequency characteristic of the transition band of the synthesized modulated signal is set to be equivalent to the root roll-off characteristic of the receiving circuit. Compensates and compensates for missing frequency components outside the transition band, and inputs the modulated signal with the root roll-off characteristic output from the band synthesis circuit to the root roll-off filter of the receiving circuit, thereby modulating with the full roll-off characteristic Demodulate the signal with a demodulator.

  In the communication method of the first invention, the spectrum converting means receives the modulated signal synthesized by the band synthesizing circuit, generates a compensation signal obtained by converting the roll-off rate of the transition band, and also modulates the modulated signal synthesized by the band synthesizing circuit. To the root roll-off characteristic of the receiving circuit, complement the frequency component missing outside the transition region of the synthesized modulation signal, and generate a complementary signal that is phase-compensated so that the phase characteristics match. Compensation signal and complementary signal are added and output.

  A second invention includes a plurality of division filters that generate sub-modulation signals that are divided into a plurality of bands on the frequency axis from the modulation signal, and a transmission signal in which each sub-modulation signal is dispersedly arranged at arbitrary locations on the frequency axis And a plurality of extraction filters for extracting each sub-modulated signal from the received signal corresponding to the transmission signal, and the modulated signal synthesized by returning the band of each sub-modulated signal to the band before the distributed arrangement In a communication device comprising a band synthesizing circuit for outputting and demodulating a modulated signal output from the band synthesizing circuit by inputting to a demodulator via a root roll-off filter of the receiving circuit, the band synthesizing circuit Spectral conversion that compensates for frequency characteristics in the transition region of the synthesized modulation signal and compensates for missing frequency components outside the transition region so that it is equivalent to the root roll-off characteristics of the circuit Includes a stage, receives the modulation signal having the root roll-off characteristic that is output from the band synthesizing circuit in the root roll-off filter of the receiving circuit is demodulated by the demodulator a modulated signal having a full roll-off characteristic.

  In the communication apparatus of the second invention, the spectrum conversion means inputs the modulation signal synthesized by the band synthesis circuit, and synthesizes the spectrum conversion filter for generating a compensation signal obtained by converting the roll-off rate of the transition band, and the band synthesis circuit. Is input to the root roll-off characteristic of the receiving circuit, and the complementary frequency signal that compensates for the missing frequency component outside the transition range of the synthesized modulation signal and compensates the phase to match the phase characteristics. Complementary signal generating means for generating, and an adding circuit for adding and outputting the compensation signal and the complementary signal.

A third invention includes a plurality of division filters that generate sub-modulation signals that are divided into a plurality of bands on the frequency axis from the modulation signal , and a transmission signal in which each sub-modulation signal is dispersedly arranged at arbitrary locations on the frequency axis And a plurality of extraction filters for extracting each sub-modulated signal from the received signal corresponding to the transmission signal, and the modulated signal synthesized by returning the band of each sub-modulated signal to the band before the distributed arrangement In the band synthesizing circuit of the communication apparatus, the receiving circuit includes a band synthesizing circuit that outputs the modulated signal output from the band synthesizing circuit to the demodulator through a root roll-off filter of the receiving circuit. The spectrum conversion method compensates for the frequency characteristics in the transition region of the synthesized modulation signal and complements the missing frequency components outside the transition region so that it is equivalent to the root roll-off characteristics of Including the.

  In the band synthesizing circuit of the third invention, the spectrum converting means receives the modulation signal synthesized by the band synthesizing circuit, generates a compensation signal obtained by converting the roll-off rate of the transition band, and the band synthesizing circuit. Complementary signal that is input the synthesized modulation signal, complements the root roll-off characteristics of the receiver circuit with the missing frequency components outside the transition range of the synthesized modulation signal, and compensates the phase so that the phase characteristics match. Complementary signal generating means, and an addition circuit that adds and outputs the compensation signal and the complementary signal.

  The present invention compensates the frequency characteristic of the combined modulated signal in the band synthesis circuit on the receiving side so as to be equal to the root roll-off characteristic of the receiving circuit, and converts the modulated signal having the root roll-off characteristic to the root roll-off characteristic of the receiving circuit. By inputting to the off filter, a modulated signal having a full roll-off characteristic is generated. As a result, the demodulator can demodulate the modulated signal having the full roll-off characteristic, prevent the occurrence of intersymbol interference, and improve the transmission characteristic.

  Further, the band dividing circuit and the band synthesizing circuit can be used as a band distribution adapter by being connected to a transmission circuit and a reception circuit of an existing modem.

It is a figure which shows the Example structure of the communication apparatus of this invention. It is a figure which shows the relationship between the synthetic | combination modulated signal and a root roll-off filter. It is a figure which shows the relationship between the band composition example in the band composition circuit 20A, and the existing modem. It is a figure which shows the example of a complementary signal in 20 A of band synthetic | combination circuits. It is a figure which shows the structural example of the conventional communication apparatus. It is a figure which shows the example of a band division in the conventional band division circuit. It is a figure which shows the band synthetic | combination example in the conventional band synthetic | combination circuit 20. FIG. It is a figure which shows the structural example of the radio | wireless communications system using a band dispersion | distribution adapter. It is a figure which shows the circuit structural example of the existing modem and a band distribution adapter. It is a figure which shows the relationship between the band composition example in the band composition circuit 20, and the existing modem.

FIG. 1 shows an embodiment of a communication apparatus according to the present invention.
In FIG. 1, the band distribution adapter of the communication apparatus is composed of a band division circuit 10 connected to a transmission circuit of an existing modem and a band synthesis circuit 20A connected to a reception circuit of the existing modem. The transmission circuit and reception circuit of the existing modem and the band division circuit 10 of the band distribution adapter shown here have the same configuration as the conventional configuration shown in FIG.

  The band synthesizing circuit 20A, which is a feature of the present invention, has a configuration in which a spectrum conversion circuit 30 is inserted between an adder circuit 26 and an IFFT circuit 27 of the conventional band synthesizing circuit 20 shown in FIG. is there. The spectrum conversion circuit 30 includes a spectrum conversion filter 31, complementary signal generation circuits 32 and 33, complementary signal phase compensation circuits 34 and 35, and an addition circuit 36.

  In the band synthesizing circuit 20A, as in the conventional band synthesizing circuit 20, the sub-modulation signal is extracted from the received signal and synthesized by the adding circuit 26. This synthesized modulated signal has a smaller occupied bandwidth than the root roll-off characteristic of the receiving circuit of the existing modem indicated by the broken line in FIG. 10 (e), and the signal components on the low frequency side and high frequency side of the spectrum are lost. ing. Specifically, the relationship between the frequency characteristics when the roll-off rate of the root roll-off filter 5 of the receiving circuit of the existing modem is α and the roll-off rate of the received signal (modulated signal synthesized by the adding circuit 26) is β is illustrated. It is shown in 2. The solid line indicates the frequency characteristic of the synthesized modulation signal, and the broken line indicates the root roll-off characteristic of the receiving circuit.

  The synthesized modulated signal has a full roll-off characteristic, and transition regions (− (1 + β) B / 2 to − (1−α) B / 2, (1−α) B / 2 to (1 + β) B The characteristics of / 2) are different from the root roll-off characteristics of the receiving circuit. In particular, the band outside the transition range of the synthesized modulation signal (-(1 + α) B / 2 to-(1 + β) B / 2, (1 + β) B / 2 to (1 + α) B / 2) is missing. . The frequency component a1 (-(1 + α) B / 2 to-(1 + β) B / 2) and the frequency component a2 ((1 + β) B / 2 to (1 + α) B / 2) lost in this way are lost on the transmission side. However, since the frequency component in the transition region is a return of the component in the pass region, the frequency component b1 ((1-α) B / 2˜ ((1−α) B / 2˜ ( 1-β) B / 2) and frequency component b2 (-(1-β) B / 2 to-(1-α) B / 2) can be complemented.

  Therefore, in the spectrum conversion circuit 30, a compensation signal obtained by converting the roll-off rate of the frequency component in the transition region so that the frequency characteristic of the synthesized modulation signal is equivalent to the root roll-off characteristic of the reception circuit, and a missing signal are obtained. The complementary signals of the frequency components b1 and b2 that complement the frequency components a1 and a2 that have been generated are generated, added, and output. This will be described in detail below.

  FIG. 3 shows an example of synthesizing a modulation signal whose band is divided into three (N = 3) in the band synthesizing circuit 20A. FIGS. 3 (a) to 3 (d) are a reprint of FIGS. 10 (a) to (d).

  The spectrum conversion filter 31 of the spectrum conversion circuit 30 inputs the modulation signal synthesized by the adder circuit 26, and the frequency characteristics of the half-value width band and the transition band are received by the receiving circuit by the filter characteristics shown by the broken line in FIG. A compensation signal in which the roll-off rate is converted so as to be equivalent to the root roll-off characteristic is output. The filter coefficient Hc (f) of the spectrum conversion filter 31 is expressed by the following equation.

  The complementary signal generation circuits 32 and 33 receive the modulated signal synthesized by the adder circuit 26 and, as shown in FIGS. 2 and 3 (f), the missing frequency component a1 on the low frequency side and high frequency side of the spectrum. , A2 to generate complementary signals extracted from the frequency components b1, b2. The complementary signal phase compensation circuits 34 and 35 compensate the phase of the complementary signal using the modulation signal synthesized by the adder circuit 26. Details will be described again with reference to FIG. The adder circuit 36 adds and synthesizes the compensation signal output from the spectrum conversion filter 31 and each of the phase-compensated complementary signals output from the complementary signal phase compensation circuits 34 and 35, thereby improving the root roll-off characteristic of the receiving circuit. The modulation signal having the same is output (FIG. 3 (g)).

  The modulation signal having the root roll-off characteristic output from the spectrum conversion circuit 30 is converted into a time-domain signal by the IFFT circuit 27, and subjected to serial / parallel conversion and D / A conversion, and input to the reception circuit of the existing modem.

  As described above, the output signal of the band synthesizing circuit 20A of the band dispersion adapter has the root roll-off characteristic, so that the modulation signal having the full roll-off characteristic is obtained by multiplying the root roll-off filter 5 by the receiving circuit of the existing modem. (FIG. 3 (h)), it is possible to prevent the occurrence of intersymbol interference and improve the transmission characteristics.

  Here, complementation and phase compensation of the missing frequency component a1 on the low frequency side of the modulation signal synthesized by the adder circuit 26 will be described with reference to FIG.

  As a complementary signal of the frequency component a1, the frequency component b1 ((1−α) B / 2 to (1−β) B / 2) in the pass band is extracted, but the center frequency of the synthesized modulation signal is extracted. When 0, the synthesized modulation signal is multiplied by a filter indicated by the following filter coefficient Hcomp (f).

  The complement signal of the frequency component b1 generated here is supplemented by adding it to the band of the missing frequency component a1 (-(1 + α) B / 2 to-(1 + β) B / 2).

  However, when the received signal has a phase gradient due to transmission, a phase difference occurs between the received signal and the complementary signal. Therefore, even if the complementary signal of the frequency component b1 is added to the band of the frequency component a1 as it is, the phase characteristic is obtained. Is not straight and the phase is distorted.

  Therefore, in the complementary signal phase compensation circuit 34, the phase θ of the frequency component c1 (− (1 + β) B / 2 to −B / 2) in the transition region that remains in the received signal spectrum without being removed by the filter, and The phase difference ψ = φ−θ is calculated between the phase φ of the frequency component d1 ((1−β) B / 2 to B / 2) that is the same as the frequency component c1. Using this phase difference ψ, the phase of the complementary signal (frequency component b1) output from the complementary signal generation circuit 32 is compensated. By using the complementary signal that has been phase-compensated in this way and adding and synthesizing the signal output from the spectrum conversion filter 31 by the adder circuit 36, a synthesized signal in which the signal component in the transition region is compensated can be obtained.

  In the embodiment described with reference to FIGS. 1 to 4, the complementary signal generation circuit in the complementary signal phase compensation circuits 34 and 35 is based on the frequency components c1 and c2 of the modulation signal synthesized by the adder circuit 26. Although the phase of the complementary signal generated in 32 and 33 is compensated, the phase of the complementary signal may be compensated based on the frequency components c1 and c2 of the compensation signal output from the spectrum conversion filter 31. .

DESCRIPTION OF SYMBOLS 1 Modulator 2 Root roll-off filter 3 D / A converter 4 A / D converter 5 Root roll-off filter 6 Demodulator 10 Band division circuit 11 A / D converter 12 Serial parallel conversion circuit 13 FFT (fast Fourier transform) Circuit 14 _{1 to} 14 _N division filter 15 ₁ to 15 _N frequency shifter 16 Adder circuit 17 IFFT (Fast Inverse Fourier Transform) circuit 18 Parallel-serial conversion circuit 19 D / A converter 20, 20A Band synthesis circuit 21 A / D converter 22 serial-parallel conversion circuit 23 FFT (fast Fourier transform) circuit 24 _{1 to} 24 _N extraction filter 25 _{1 to} 25 _N frequency shifter 26 addition circuit 27 IFFT (fast inverse Fourier transform) circuit 28 parallel-serial conversion circuit 29 D / A converter 30 Spectrum conversion circuit 31 Spectrum conversion filter 32, 33 Complementary signal generation circuit 34, 35 Complement Signal phase compensation circuit 36 addition circuit

Claims (6)

The modulation signal is input from the transmission circuit to the band division circuit,
The band dividing circuit generates a sub modulation signal that is divided into a plurality of bands on the frequency axis from the modulation signal by a plurality of division filters, and a transmission signal in which each sub modulation signal is dispersedly arranged at an arbitrary place on the frequency axis Output
The band synthesizing circuit extracts each sub-modulated signal from the received signal corresponding to the transmission signal by a plurality of extraction filters, returns the band of each sub-modulated signal to the band before the dispersion arrangement, and combines the modulated signal Output,
In the communication method of demodulating the modulation signal output from the band synthesis circuit by inputting to the demodulator via the root roll-off filter of the reception circuit,
The band synthesizing circuit is a spectrum converting means for inputting the synthesized modulation signal, and compensates for the frequency characteristics of the transition area of the synthesized modulation signal so as to be equivalent to the root roll-off characteristics of the receiving circuit. To compensate for missing frequency components outside the region,
A modulation signal having a root roll-off characteristic output from the band synthesis circuit is input to a root roll-off filter of the receiving circuit, and the modulation signal having a full roll-off characteristic is demodulated by the demodulator. Method. The communication method according to claim 1,
The spectrum conversion means includes
The modulation signal synthesized by the band synthesizing circuit is input, and a compensation signal obtained by converting the roll-off rate of the transition band is generated.
The modulation signal synthesized by the band synthesizing circuit is input, and the root roll-off characteristic of the receiving circuit is supplemented with the frequency component missing outside the transition range of the synthesized modulation signal, and the phase characteristics match. To generate a complementary signal with phase compensation
The communication method, wherein the compensation signal and the complementary signal are added and output. A band division circuit that includes a plurality of division filters that generate sub-modulation signals that are divided into a plurality of bands on the frequency axis from the modulation signal, and that outputs a transmission signal in which each sub-modulation signal is distributed and arranged at arbitrary locations on the frequency axis When,
Band synthesis that includes a plurality of extraction filters that extract each sub-modulated signal from the received signal corresponding to the transmission signal, and outputs a modulated signal that is synthesized by returning the band of each sub-modulated signal to the band before the dispersion arrangement A communication device configured to input and demodulate a modulation signal output from the band synthesis circuit to a demodulator via a root roll-off filter of a reception circuit,
The band synthesizing circuit compensates for the frequency characteristic of the synthesized modulation signal in the transition region so as to be equivalent to the root roll-off characteristic of the receiving circuit, and compensates for the frequency component missing outside the transition region. Including means,
A modulation signal having a root roll-off characteristic output from the band synthesis circuit is input to a root roll-off filter of the receiving circuit, and the modulation signal having a full roll-off characteristic is demodulated by the demodulator. apparatus. The communication device according to claim 3.
The spectrum conversion means includes
A spectrum conversion filter that inputs a modulation signal synthesized by the band synthesizing circuit and generates a compensation signal obtained by converting a roll-off rate of a transition band;
The modulation signal synthesized by the band synthesizing circuit is input, and the root roll-off characteristic of the receiving circuit is supplemented with the frequency component missing outside the transition range of the synthesized modulation signal, and the phase characteristics match. Complementary signal generation means for generating a complementary signal phase-compensated as described above,
An adder circuit that adds and outputs the compensation signal and the complementary signal. A band division circuit that includes a plurality of division filters that generate sub-modulation signals that are divided into a plurality of bands on the frequency axis from the modulation signal, and that outputs a transmission signal in which each sub-modulation signal is distributed and arranged at arbitrary locations on the frequency axis When,
Band synthesis that includes a plurality of extraction filters that extract each sub-modulated signal from the received signal corresponding to the transmission signal, and outputs a modulated signal that is synthesized by returning the band of each sub-modulated signal to the band before the dispersion arrangement Circuit and
In the band synthesizing circuit of the communication device, the modulation signal output from the band synthesizing circuit is input to the demodulator through the root roll-off filter of the receiving circuit and demodulated.
Comprising spectrum conversion means that compensates for the frequency characteristics of the transition region of the synthesized modulation signal and complements the missing frequency components outside the transition region so as to be equivalent to the root roll-off characteristics of the receiving circuit. A band synthesis circuit. The band synthesis circuit according to claim 5, wherein
The spectrum conversion means includes
A spectrum conversion filter that inputs a modulation signal synthesized by the band synthesizing circuit and generates a compensation signal obtained by converting a roll-off rate of a transition band;
The modulation signal synthesized by the band synthesizing circuit is input, and the root roll-off characteristic of the receiving circuit is supplemented with the frequency component missing outside the transition range of the synthesized modulation signal, and the phase characteristics match. Complementary signal generation means for generating a complementary signal phase-compensated as described above,
A band synthesizing circuit comprising: an adder circuit that adds and outputs the compensation signal and the complementary signal.

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