JP2009049651A - Communication device and peak suppression method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a communication device which enables both the reduction of an operation amount and the improvement of suppression performance. <P>SOLUTION: The communication device separates a complex transmission signal into a real part signal and an imaginary part signal, performs peak suppression processing to the real number signal of the separated signal, and is provided with: a peak search unit 11 which obtains a maximum electric power sample whose electric power value becomes maximum among complex transmission signals; a phase calculation unit 12 which obtains a phase of the maximum electric power sample; a phase discrimination unit 13 which obtains a phase rotation amount based on the phase and a predetermined target phase; a phase rotation unit 14 which carries out the phase rotation of the complex transmission signal based on the phase rotation amount; and a real number peak suppression processing unit 16 which performs real number peak suppression processing to the real part signal and the imaginary part signal of the signal after phase rotation, respectively. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a communication apparatus that performs peak suppression processing on a multicarrier signal.

  Conventionally, as one of peak power suppression methods for multi-carrier signals such as OFDM (Orthogonal Frequency Division Multiplexing), a Tone Reservation (TR) method for transmitting a peak suppression signal on a subcarrier different from an information transmission subcarrier is known. ing.

  In addition, as one method for calculating a TR-type peak suppression signal for a complex baseband signal, there is a method in which a peak suppression signal calculation algorithm for a real baseband signal is independently applied to a real part / imaginary part of a complex baseband signal. Are known. This method has a feature that a simple calculation is sufficient as compared with the case of calculating the peak suppression signal for the complex baseband signal, but the peak suppression performance is inferior.

  As a technique for improving this deterioration, for example, in Non-Patent Document 1 below, a signal in which a plurality of different phase rotation amounts are given to the original complex baseband signal is created, and the real part / imaginary part of each created signal is independently determined. A technique for performing peak suppression and selecting a signal with the best suppression performance is disclosed. In this method, the greater the number of signals given different amounts of phase rotation, the better the suppression characteristics. For example, in Non-Patent Document 1 below, three types of signals are generated by rotating the complex baseband signals by π / 4, π / 2, and 3π / 4 phases, respectively, and the four types of complex signals combined with the original signal are generated. Real number baseband algorithm is applied to real part / imaginary part independently. It is shown that by selecting and outputting the signal having the best suppression performance among these four types of signals, the characteristics are improved as compared with the case where peak suppression is performed only on the original signal.

B. S. Krongold and D. L Jones, “An Active-Set Approach for OFDM PAR Reduction via Tone Reservation”, IEEE Transactions on Signal Processing, Vol. 52, No. 2, Feb. 2004.

  However, according to the conventional peak power suppression technique described in Non-Patent Document 1, the peak suppression processing is performed on a plurality of complex signals in order to improve the suppression characteristics. Therefore, there has been a problem that the amount of calculation increases. For example, when using an original signal and a signal obtained by rotating the phase by π / 4, π / 2, and 3π / 4, the amount of computation is four times as large as when performing peak suppression processing when only the original signal is used. Become.

  The present invention has been made in view of the above, and provides a communication apparatus and a peak suppression method capable of realizing both a reduction in the amount of peak suppression processing for complex baseband signals and an improvement in peak suppression performance. With the goal.

  In order to solve the above-described problems and achieve the object, the present invention separates a complex transmission signal into a real signal and an imaginary signal, and performs a peak suppression process on the real signal for the separated signal. A peak search means for obtaining a maximum power sample having a maximum power value in the complex transmission signal; a phase calculation means for obtaining a phase of the maximum power sample; and the phase and a predetermined target phase. A phase rotation amount calculating step for obtaining a phase rotation amount, phase rotation means for rotating the phase of the complex transmission signal based on the phase rotation amount, and a real part signal and an imaginary part signal of the signal after the phase rotation, Real number peak suppression processing means for performing the real number peak suppression processing, respectively.

  According to the present invention, the phase rotation amount is calculated so that the phase of the maximum power sample of the signal to be peak-suppressed becomes a predetermined target phase, and the signal to be peak-suppressed is rotated by the phase rotation amount, The signal after phase rotation is separated into a real part and an imaginary part, and peak suppression processing for real signals is performed on each signal, so both the amount of calculation of peak suppression processing and the improvement of peak suppression performance are improved. There is an effect that it can be realized.

  Embodiments of a peak suppression method and a communication apparatus according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a diagram illustrating a functional configuration example of a communication device according to a first embodiment of the present invention. As shown in FIG. 1, a communication apparatus according to the present embodiment includes a transmission data generation unit 1 that generates a transmission data sequence, and a modulation unit 2 that maps the transmission data sequence to each subcarrier and performs symbol mapping for each subcarrier. An IFFT (Inverse Fast Fourier Transform) unit 3 that performs inverse fast Fourier transform on the symbol-mapped transmission data sequence, a complex peak suppression unit 4 that performs peak suppression processing on the data after IFFT, and a CP for the peak suppression signal CP addition unit 5 for adding (Cyclic Prefix), D / A (digital-analog) conversion unit 6 for analog conversion of the signal after CP addition, and frequency conversion and power amplification for the converted analog signal An RF (Radio Frequency) unit 7 and an antenna 8 that transmits an output signal of the RF unit as a radio signal are configured.

  Moreover, FIG. 2 is a figure which shows the function structural example of the complex peak suppression part 4 of this Embodiment. As shown in FIG. 2, the complex peak suppressing unit 4 of the present embodiment includes a control unit 9 that controls peak suppression repetition processing, a selection unit 10 that selects a signal to be processed for peak suppression processing, and processing A peak search unit 11 that searches for a sample with the maximum power from the target signal, a phase calculation unit 12 that calculates the phase of the searched power maximum sample, and a phase rotation amount based on the calculated phase. A phase determination unit 13 that outputs an initialization signal for performing initialization of peak suppression processing, a phase rotation unit 14 that performs phase rotation of the phase rotation amount calculated for all sample points of the processing target signal, An I / Q separation unit 15 that separates a signal after phase rotation into a real part / imaginary part, and a real number peak suppression unit that performs peak suppression processing on the real number signal with respect to the real part signal separated by the I / Q separation unit 15 16-1 and I A real number peak suppression unit 16-2 that performs peak suppression processing on the imaginary part signal with respect to the real part signal separated by the Q separation unit 15, and a real part signal and a real number peak that are peak-suppressed by the real number peak suppression unit 16-1. And an I / Q combining unit 17 that performs I / Q combining with the imaginary part signal whose peak is suppressed by the suppressing unit 16-2.

  Next, the operation of the present embodiment will be described. First, the transmission data generation unit 1 generates a transmission data sequence, and the modulation unit 2 maps the transmission data sequence to each subcarrier, and then performs symbol mapping for each subcarrier. Then, IFFT unit 3 performs inverse fast Fourier transform on the symbol-mapped transmission data sequence and outputs the result to complex peak suppression unit 4 as a complex signal. The complex peak suppression unit 4 performs peak suppression processing described later on the inverse fast Fourier transform signal, and the CP addition unit 5 performs CP (cyclic prefix) addition, filtering processing, etc. on the peak suppressed signal. . The D / A converter 6 converts the signal after the CP addition into an analog signal, the RF unit 7 performs frequency conversion, power amplification, and the like, and the antenna 8 transmits the output signal of the RF unit 7.

  Next, the peak suppression process of this embodiment will be described. The complex signal for one inverse fast Fourier transform output from the IFFT unit 3 is input to the selection unit 10 of the complex peak suppression unit 4. The control unit 9 monitors the input to the selection unit 10, and when the selection unit 10 receives an input from the IFFT unit 3, the selection unit 10 receives the complex signal input as the first processing target signal. A signal is selected and output to the peak search unit 11 and the phase rotation unit 14.

  The peak search unit 11 searches for a sample having the maximum power among the signals to be processed. The phase calculation unit 12 calculates the phase of the searched power maximum sample and outputs it to the phase determination unit 13. Then, the phase determination unit 13 calculates a phase rotation amount instructed to the phase rotation unit 14 based on the calculated phase of the maximum power sample and outputs the phase rotation amount to the phase rotation unit 14, and the real number peak suppression unit 16-1, The initialization signal to 16-2 is output to the real number peak suppression units 16-1 and 16-2. The phase rotation amount calculated at this time is a rotation amount such that the phase of the maximum power sample becomes the target phase (a value included in a predetermined range centered on “0”). For example, when the target phase is “0” and the phase of the maximum power sample is X, the calculated phase rotation amount is calculated as “0” −X = −X. The target phase is not limited to “0”, and may be set to a numerical value within a predetermined range so as to satisfy a desired required value of peak suppression performance in consideration of an error and other conditions.

  The phase determining unit 13 does not output an initialization signal when the calculated phase rotation amount is “0”. Therefore, in this case, the real number peak suppression units 16-1 and 16-2 are not initialized. When the calculated phase rotation amount is a value other than “0”, the phase determination unit 13 outputs an initialization signal, and the real number peak suppression units 16-1 and 16-2 are initialized.

  The phase rotation unit 14 performs phase rotation of the phase rotation amount for all samples of the processing target signal based on the phase rotation amount output from the phase determination unit 13, and the signal after the phase rotation is an I / Q separation unit 15. Output to. The I / Q separation unit 15 divides the input phase-rotated signal into a real part and an imaginary part, the real part signal into the real number peak suppressing part 16-1, and the imaginary part signal into the real number peak suppressing part 16-2. , Respectively.

  The real number peak suppression units 16-1 and 16-2 perform peak suppression processing on the real number signal on the real part signal and the imaginary part signal, respectively. At this time, when the phase determination unit 13 outputs the initialization signal, the peak suppression process is initialized. As a peak suppression processing method, here, for example, a case where the method described in “B. S. Krongold and D. L Jones,“ An Active-Set Approach for OFDM PAR Reduction via Tone Reservation ”” will be described. In this method, the peak power is reduced by repeating the peak suppression processing for the maximum power sample, but it is assumed that the signal phase is constant regardless of the number of repetitions. On the other hand, when the phase rotation processing of the phase rotation amount other than “0” is performed in the phase rotation unit 14, the iteration processing of the previous number of repetitions and the phase processed in the real number peak suppression units 16-1 and 16-2 are It will be different. Therefore, in the present embodiment, when the calculated phase rotation amount is a value other than “0”, the phase determination unit 13 outputs an initialization signal to the real number peak suppression units 16-1 and 16-2, and the real number Initialize peak suppressors 16-1 and 16-2 (initialize parameters used in processing of real number peak suppressors 16-1 and 16-2, and initialize the number of repetitions of peak suppression processing for real number signals. I decided to.

  The real number peak suppression units 16-1 and 16-2 each output an output signal to the I / Q combining unit 17, and the I / Q combining unit 17 combines these output signals as complex signals, and sends them to the selection unit 10. The control unit 9 is notified that the combined complex signal has been output. With the processing so far, the first overall processing of the complex peak suppressing unit 4 is completed.

  Next, when the control unit 9 detects that the selection unit 10 receives the input of the complex signal synthesized from the I / Q synthesis unit, the control unit 9 outputs the output of the I / Q synthesis unit 17 to the selection unit 10 as a second overall process. Instructs the signal to be selected as a signal to be processed. Subsequent selection unit 10, peak search unit 11, phase calculation unit 12, phase determination unit 13, phase rotation unit 14, I / Q separation unit 15, real number peak suppression units 16-1, 16-2, I / Q synthesis The processing of the unit 17 is the same as the initial processing except that the processing target signal is a complex signal synthesized. When the processing of the I / Q combining unit 17 is completed, the processing from the selecting unit 10 is started again. Thereafter, the selecting unit 10, the peak searching unit 11, the phase calculating unit 12, the phase determining unit 13, and the phase rotating unit 14 are started. , I / Q separator 15, real peak suppressor 16-1, 16-2, I / Q synthesizer 17 repeats the total number of processes, or the peak suppression level is a predetermined reference. The process is repeated until it is satisfied. The number of repetitions is counted when the selection unit 10 processes the complex signal input from the IFFT unit 3 for the first time, and thereafter the count is incremented every time the selection unit 10 receives an output from the I / Q combining unit 17. The number of repetitions. That is, the number of repetitions managed by the control unit 9 apart from the number of repetitions initialized when the real number peak suppression units 16-1 and 16-2 receive the initialization signal (the number of repetitions of peak suppression processing for the real number signal). (Hereinafter referred to as the number of repetitions of the entire process).

  The control unit 9 monitors whether the number of repetitions of the entire process reaches a predetermined number, or whether the peak suppression level of the complex signal output from the I / Q combining unit 17 satisfies a predetermined standard. When the number of repetitions of the entire process reaches a predetermined number, or when the peak suppression level of the complex signal output from the I / Q combining unit 17 satisfies a predetermined criterion, the inverse of one inverse fast Fourier transform is performed. It is determined that the peak suppression processing for the fast Fourier transform signal is finished, and instructs the I / Q combining unit 17 to output the combined complex signal to the CP adding unit 5. Further, the control unit 9 transmits an initialization signal to the real number peak suppressing units 16-1 and 16-2, and the real number peak suppressing units 16-1 and 16-2 are initialized. Then, the inverse fast Fourier transform signal for the next inverse fast Fourier transform is input from the IFFT unit 3 and the above-described peak suppression processing is performed.

  In the present embodiment, the control unit 9 monitors the input of the selection unit 10 and controls the repetition of the entire process. However, the present invention is not limited to this, and the selection unit 10 has the function of the control unit 9. The control unit 9 may be deleted.

  As described above, in the present embodiment, the phase of the maximum power sample of the signal that is the target of peak suppression is obtained, the phase rotation amount is obtained so that the phase of the maximum power sample becomes the target phase, and the target of peak suppression is determined. Is rotated by the amount of phase rotation, and the signal after phase rotation is separated into a real part and an imaginary part, and peak suppression processing for the real number signal is performed on each signal. For this reason, it is possible to improve the deterioration of the suppression performance, which becomes a problem when the real number peak suppression is performed on the real part and the imaginary part of the signal, respectively. Compared to the conventional method of performing peak suppression processing on a plurality of signals given different phase rotation amounts and selecting a signal with good peak suppression performance, the amount of calculation can be greatly reduced.

Embodiment 2. FIG.
FIG. 3 is a diagram illustrating a functional configuration example of the complex peak suppressing unit 4a according to the second embodiment of the present invention. As shown in FIG. 3, the complex peak suppressing unit 4a of the present embodiment is the same as the complex peak suppressing unit 4 of the first embodiment, except that the real number peak suppressing unit 16-2 is deleted. The configuration of the communication apparatus according to the present embodiment is the same as that of the communication apparatus according to the first embodiment, except that the complex peak suppressing unit 4 is replaced with the complex peak suppressing unit 4a. Components having the same functions as those in the first embodiment are given the same reference numerals and description thereof is omitted. Only the parts different from the first embodiment will be described below.

  Next, the peak suppression process of this embodiment will be described. Only the parts different from the first embodiment will be described below. The processes of the control unit 9, the selection unit 10, the peak search unit 11, the phase calculation unit 12, the phase determination unit 13, the phase rotation unit 14, and the I / Q separation unit 15 are the same as those in the first embodiment. However, the phase determination unit 13 outputs only the real number peak suppression unit 16-1 when transmitting the initialization signal. Further, the I / Q separation unit 15 outputs the real part signal only to the real number peak suppression unit 16-1 as in the first embodiment, and outputs the imaginary part signal to the I / Q synthesis unit 17.

  Real number peak suppression section 16-1 performs the same processing as in the first embodiment, and outputs the peak-suppressed output signal to I / Q combining section 17 as in the first embodiment. The I / Q combining unit 17 combines the real part signal after the peak suppression processing output from the real number peak suppressing unit 16-1 and the imaginary part signal output from the I / Q separation unit 15 to select as a complex signal. 10 is output. The other peak suppression processing of the present embodiment is the same as that of the first embodiment. The operations other than the peak suppression processing of the present embodiment are the same as those of the first embodiment.

  As described above, in the present embodiment, the phase of the maximum power sample of the signal that is the target of peak suppression is obtained, the phase rotation amount is obtained so that the phase of the maximum power sample becomes the target phase, and the target of peak suppression is determined. Is rotated by the amount of phase rotation, and the signal after phase rotation is separated into a real part and an imaginary part, and peak suppression processing is performed on the real number signal only for the real part signal. For this reason, the amount of calculation can be further reduced as compared with the first embodiment. In the present embodiment, the peak suppression performance close to the peak suppression performance of the first embodiment can be obtained by setting the target phase in the vicinity of “0”.

Embodiment 3 FIG.
FIG. 4 is a diagram illustrating a functional configuration example of the phase determination unit 13a according to the third embodiment of the present invention. As illustrated in FIG. 4, the phase determination unit 13 a according to the present embodiment includes a comparison value generation unit 18, a comparison unit 19, a selection unit 20, and a zero generation unit 21. The configuration of the communication apparatus according to the present embodiment is the same as that of the communication apparatus according to the first or second embodiment, except that the phase determination unit 13 is replaced with the phase determination unit 13a. Components having the same functions as those in the first embodiment or the second embodiment are denoted by the same reference numerals and description thereof is omitted. Only the parts different from the first embodiment or the second embodiment will be described below.

  It continues and demonstrates operation | movement of the phase determination part 13a of this Embodiment. First, the phase (θ) of the maximum power sample input from the phase calculation unit 12 is input to the comparison unit 19 and the selection unit 20. Further, the zero generation unit 21 generates “0” and outputs it to the selection unit 20. The comparison value generation unit 18 holds the phase allowable value Δθ and outputs Δθ to the comparison unit 19. However, in the present embodiment, the phase allowable value Δθ is a numerical value other than “0”.

  The comparison unit 19 compares the input θ and Δθ, and controls the selection unit 20 based on the comparison result. Specifically, if | θ | <| Δθ |, the selection unit 20 is instructed to select and output “0” input from the zero generation unit 21; otherwise, θ is selected. And instruct it to output. Then, the selection unit 20 selects an input value based on an instruction from the comparison unit 19 and outputs the selection result to the phase rotation unit 14. Further, when the comparison unit 19 instructs to select and output θ, the comparison unit 19 outputs the initialization signal to the real number peak suppression units 16-1 and 16-2 (in the case of the configuration of the second embodiment, a real number). Output only to the peak suppressor 16-1. The operations other than the phase determination unit 13a in the present embodiment are the same as those in the first or second embodiment.

  In this embodiment, the phase allowable value Δθ is compared as a single value. However, the comparison method is not limited to this, and instead of Δθ, the phase allowable value is defined as a range of Δθ1 to Δθ2, and the comparison unit 19 In the case of Δθ1 <θ <Δθ1, it may be instructed to select and output “0”, and in other cases to instruct to select and output θ.

  As described above, in the present embodiment, when the phase allowable value is set in advance and the phase change before and after the peak suppression processing is equal to or smaller than the absolute value of the phase allowable value, the real number peak suppressing units 16-1 and 16- 2 was not initialized. For this reason, when there is a minute change due to an error or the like, the real number peak suppression units 16-1 and 16-2 are not initialized, and therefore, more peaks than in the first and second embodiments. Suppression performance is improved.

  Note that the phase allowable value Δθ held by the comparison value generation unit 18 may be changed according to the number of repetitions of the entire process, instead of a constant value. For example, when Δθ = 0 is set for the first process and the value is gradually increased according to the number of repetitions, the value is determined according to the operating characteristics of the real number peak suppression units 16-1 and 16-2 at the subsequent stage. The peak suppression performance is further improved.

Embodiment 4 FIG.
FIG. 5 is a diagram illustrating a functional configuration example of the phase determination unit 13b according to the fourth embodiment of the present invention. As shown in FIG. 5, the phase determination unit 13b of the present embodiment is the same as the phase determination unit 13b of the third embodiment, except that a counter 22 is added to the phase determination unit 13a of the third embodiment. The configuration of the communication apparatus according to the present embodiment is the same as that of the communication apparatus according to the first embodiment or the second embodiment except that the phase determination unit 13 is replaced with the phase determination unit 13b. Components having the same functions as those in the first embodiment or the second embodiment are denoted by the same reference numerals and description thereof is omitted. Hereinafter, only parts different from the first embodiment, the second embodiment, or the third embodiment will be described.

  Subsequently, the operation of the phase determination unit 13b of the present embodiment will be described. First, the phase θ of the maximum power sample input from the phase calculation unit 12 is input to the comparison unit 19 and the selection unit 20. Further, the zero generation unit 21 generates “0” and outputs it to the selection unit 20. The comparison value generation unit 18 holds the phase allowable value Δθ as in the third embodiment, and outputs Δθ to the comparison unit 19. In the present embodiment, the phase allowable value Δθ is set to a numerical value other than “0” as in the third embodiment.

  The comparison unit 19 compares the input θ and Δθ, and outputs a control signal to the counter 22 based on the comparison result. Specifically, in the case of | θ | <| Δθ |, the control signal that instructs the selection unit 20 to select and output “0” input from the zero generation unit 21 (hereinafter referred to as “0” selection). In other cases, a control signal instructing to select and output θ is output.

  The counter 22 monitors the control signal input from the comparison unit 19 and counts the number of times the “0” selection signal has been continuously received. When the number of consecutive receptions reaches a predetermined number set in advance, the initialization signal is converted into real number peak suppression units 16-1 and 16-2 (real numbers in the case of the configuration of the second embodiment). Output only to the peak suppressor 16-1) and initialize the count value. The counter 22 outputs the control signal input from the comparison unit 19 to the selection unit 20, and the selection unit 20 performs selection based on the control signal and outputs the selection result to the moving rotation unit 14. The operations other than the phase determination unit 13b in the present embodiment are the same as those in the first or second embodiment. Further, when the counter 22 selects and outputs θ, the counter 22 outputs the initialization signal to the real number peak suppression units 16-1 and 16-2 (in the case of the configuration of the second embodiment, the real number peak). To the suppression unit 16-1 only).

  Depending on how the real number peak suppression units 16-1 and 16-2 are implemented, if peak suppression processing is continued without being initialized in the middle of one OFDM symbol, the amount of calculation increases due to an increase in inverse matrix size or the like. Problems may occur. In this case, it may be necessary to constrain the maximum inverse matrix size. In the present embodiment, it is possible to set an upper limit on the number of continuous executions of the peak suppression processing in consideration of such restrictions, and thus the amount of calculation can be further reduced.

  Note that the phase tolerance is determined as a range of Δθ1 to Δθ2 as described in the third embodiment, and the comparison unit 19 instructs to select and output “0” when Δθ1 <θ <Δθ1. In other cases, a control signal instructing to select and output θ may be output.

  As described above, in the present embodiment, the counter 22 counts the number of times the “0” selection signal is continuously received, and the real number peak suppression unit when the number of times the counter 22 is continuously received exceeds a predetermined number. An initialization signal is transmitted to 16-1 and 16-2. Therefore, it is possible to limit the number of times that the real number peak suppression units 16-1 and 16-2 are repeatedly performed without being initialized, and to further improve the peak suppression performance as compared with the first to third embodiments. Can do.

  As described above, the communication apparatus and the peak suppression method according to the present invention are useful for a communication apparatus that transmits a multicarrier signal, and are particularly suitable for a communication apparatus that achieves both a reduction in the amount of computation and an improvement in peak suppression performance. ing.

It is a figure which shows the function structural example of Embodiment 1 of the communication apparatus concerning this invention. 3 is a diagram illustrating a functional configuration example of a complex peak suppressing unit according to Embodiment 1. FIG. FIG. 10 is a diagram illustrating a functional configuration example of a complex peak suppressing unit according to a second embodiment. FIG. 10 is a diagram illustrating a functional configuration example of a phase determination unit according to a third embodiment. FIG. 10 is a diagram illustrating a functional configuration example of a phase determination unit according to a fourth embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transmission data generation part 2 Modulation part 3 IFFT part 4, 4a Complex peak suppression part 5 CP addition part 6 D / A conversion part 7 RF part 8 Antenna 9 Control part 10 Selection part 11 Peak search part 12 Phase calculation part 13, 13a , 13b Phase determination unit 14 Phase rotation unit 15 I / Q separation unit 16-1, 16-2 Real number peak suppression unit 17 I / Q combination unit 18 Comparison value generation unit 19 Comparison unit 20 Selection unit 21 Zero generation unit 22 Counter

Claims (9)

A communication device that separates a complex transmission signal into a real part signal and an imaginary part signal, and performs peak suppression processing on the real signal for the separated signal,
Peak search means for obtaining a maximum power sample having a maximum power value among the complex transmission signals;
A phase calculation means for determining a phase of the maximum power sample;
A phase rotation amount calculating means for obtaining a phase rotation amount based on the phase and a predetermined target phase;
Phase rotation means for rotating the phase of the complex transmission signal based on the amount of phase rotation;
Real number peak suppression processing means for performing the real number peak suppression processing on the real part signal and the imaginary part signal of the signal after the phase rotation,
A communication apparatus comprising: A communication device that separates a complex transmission signal into a real part signal and an imaginary part signal, and performs peak suppression processing on the real signal for the separated signal,
Peak search means for obtaining a maximum power sample having a maximum power value among the complex transmission signals;
A phase calculation means for determining a phase of the maximum power sample;
A phase rotation amount calculating means for obtaining a phase rotation amount based on the phase and a predetermined target phase;
Phase rotation means for rotating the phase of the complex transmission signal based on the amount of phase rotation;
Real number peak suppression processing means for performing the real number peak suppression processing on the real part signal of the signal after the phase rotation;
A communication apparatus comprising:   The communication apparatus according to claim 1, wherein the predetermined target phase is set to zero. Peak suppression complex signal generation means for generating a complex signal after peak suppression processing based on the signal after the real number peak suppression processing;
Further comprising
The peak search means, the phase calculation means, the phase rotation amount calculation means, the phase rotation means, the real peak suppression processing means, and the peak suppression complex signal generation means are processed as a set of peak suppression processing, and the peak suppression The process is repeated a predetermined number of times,
The second or subsequent peak suppression processing uses the complex signal generated by the peak-suppressed complex signal generation unit of the previous iteration number as the complex transmission signal. The communication device described. Peak suppression complex signal generation means for generating a complex signal after peak suppression processing based on the signal after the real number peak suppression processing;
Peak suppression criterion determination means for determining whether or not the complex signal satisfies a predetermined peak suppression criterion;
Further comprising
The processing by the peak search means, the phase calculation means, the phase rotation amount calculation means, the phase rotation means, the real number peak suppression processing means, the peak suppression complex signal generation means, and the peak suppression reference determination means is a set of peaks. It is assumed that the peak suppression process is repeated until the peak suppression criterion determination unit determines that the complex signal satisfies a predetermined peak suppression criterion,
The second or subsequent peak suppression processing uses the complex signal generated by the peak-suppressed complex signal generation unit of the previous iteration number as the complex transmission signal. The communication device described. Tolerance value comparing means for judging whether or not the phase rotation amount exceeds a predetermined tolerance range;
Further comprising
6. The communication according to claim 4, wherein when the phase rotation amount exceeds a predetermined allowable range, processing by the phase rotation amount calculation unit is executed and initialization of the real number peak suppression processing is performed. apparatus. Counting means for counting the number of times the phase rotation amount is determined to be within a predetermined range;
Further comprising
The communication apparatus according to claim 6, wherein the real number peak suppression process is initialized when the counted number exceeds a predetermined limit number. A peak suppression method that separates a complex transmission signal into a real part signal and an imaginary part signal, and performs a real number peak suppression process, which is a peak suppression process for a real number signal, on the separated signal,
A peak search step for obtaining a maximum power sample having a maximum power value among the complex transmission signals;
A phase calculating step for determining a phase of the maximum power sample;
A phase rotation amount calculating step for obtaining a phase rotation amount based on the phase and a predetermined target phase;
A phase rotation step for rotating the phase of the complex transmission signal based on the amount of phase rotation;
Real number peak suppression processing step for performing the real number peak suppression processing on the real part signal and the imaginary part signal of the signal after the phase rotation,
A peak suppression method characterized by comprising: A peak suppression method that separates a complex transmission signal into a real part signal and an imaginary part signal, and performs a real number peak suppression process, which is a peak suppression process for a real number signal, on the separated signal,
A peak search step for obtaining a maximum power sample having a maximum power value among the complex transmission signals;
A phase calculating step for determining a phase of the maximum power sample;
A phase rotation amount calculating step for obtaining a phase rotation amount based on the phase and a predetermined target phase;
A phase rotation step for rotating the phase of the complex transmission signal based on the amount of phase rotation;
Real number peak suppression processing step for performing the real number peak suppression processing on the real part signal of the signal after the phase rotation;
A peak suppression method characterized by comprising:

Images