WO2022013994A1 - Multitone signal generation device and multitone signal generation method - Google Patents

Abstract

This multitone signal generation device (100) comprises an initial value calculation unit (1) that calculates an initial value used in a convergence computation for reducing the PAPR of a multitone signal (MS), a waveform data generation unit (2) that generates waveform data (WD) indicating the waveform of the multitone signal (MS) in which the PAPR is reduced by executing the convergence computation using the initial value, and a multitone signal output unit (3) that outputs the multitone signal (MS) in accordance with the waveform data (WD) generated by the waveform data generation unit (2). In the present invention: the initial value includes M initial phases (θ₁ to θ_M) corresponding to M tone signals (TS₁ to TS_M) included in the multitone signal (MS); the initial value calculation unit (1) calculates each of the M initial phases (θ₁ to θ_M) by executing an algebraic calculation using a prescribed numerical expression; and said numerical expression includes a variable corresponding to the tone number (M) of the multitone signal (MS) and a variable corresponding to an integer (r) that is a mutual prime of the tone number (M).

Description

Multitone signal generator and multitone signal generation method

The present disclosure relates to a multitone signal generation device and a multitone signal generation method.

Conventionally, a technique for measuring frequency characteristics (including amplitude characteristics and phase characteristics; the same applies hereinafter) at the RF (Radio Frequency) front end of a wireless communication device has been developed using a multitone signal. Further, a technique for correcting the frequency characteristic in the RF front end by executing digital signal processing according to the result of such measurement has been developed (see, for example, Patent Document 1).

Normally, a multitone signal has a high peak power to average power ratio (hereinafter referred to as "PAPR"). By using a multitone signal with high PAPR, spurious is generated in the non-linear element of the RF front end. The generation of spurious inside the RF front end makes it difficult to accurately measure the frequency characteristics of the RF front end. Therefore, it is preferable to use a multitone signal having a low PAPR. In other words, it is preferable to reduce the PAPR of the multitone signal.

On the other hand, Non-Patent Document 1 discloses a technique for generating a multitone signal having a low crest factor. That is, Non-Patent Document 1 discloses a technique for generating a multitone signal having a low PAPR. In other words, Non-Patent Document 1 discloses a technique for reducing PAPR of a multitone signal.

Hereinafter, a multitone signal with reduced PAPR may be referred to as a "low PAPR multitone signal". That is, the low PAPR multitone signal has a lower PAPR than the PAPR in a normal multitone signal.

International Publication No. 2009/022697

The technique described in Non-Patent Document 1 (hereinafter referred to as "conventional technique") executes a convergence operation in generating a multitone signal having a low crest factor. Where the multitone signal includes a plurality of tone signals, the initial value in the convergence operation includes a plurality of initial phases corresponding to the plurality of tone signals. In the prior art, a Barker code is used as an initial value in the convergence operation.

Here, the maximum value of the code length in the Barker code is 13. Therefore, when the number of tone signals included in the multitone signal (hereinafter referred to as “the number of tones”) is 13 or less, the Barker code can be used as the initial value in the convergence operation. On the other hand, when the number of tones is 14 or more, the Barker code cannot be used as the initial value in the convergence operation. In such a case, PBC (Polyphase Barker Code) is used as the initial value in the convergence operation. PBC is an extension of the Barker code.

However, when PBC is used as the initial value in the convergence operation, a dedicated convergence operation for calculating the PBC is separately required. Then, it is separately required to calculate the initial value in the dedicated convergence operation. Non-Patent Document 1 does not disclose a method for calculating an initial value in such a dedicated convergence operation. Therefore, in the prior art, there is a problem that it is difficult to generate a multitone signal having a low crest factor when the number of tones is 14 or more. In other words, in the prior art, there is a problem that it is difficult to generate a low PAPR multitone signal for an arbitrary number of tones.

The present disclosure has been made to solve the above-mentioned problems, and a multitone signal generation device and a multitone signal generation method capable of generating a low PAPR multitone signal for an arbitrary number of tones are provided. The purpose is to provide.

The multitone signal generator according to the present disclosure includes an initial value calculation unit that calculates an initial value used for a convergence calculation for reducing PAPR of a multitone signal, and a PAPR by executing a convergence calculation using the initial value. It is provided with a waveform data generation unit that generates waveform data indicating the waveform of the multitone signal with reduced multitone signal, and a multitone signal output unit that outputs the multitone signal corresponding to the waveform data generated by the waveform data generation unit. , The initial value includes a plurality of initial phases corresponding to a plurality of tone signals included in the multitone signal, and the initial value calculation unit performs a plurality of initial values by performing an algebraic calculation using a predetermined mathematical formula. Each of the phases is calculated, and the formula includes an algebra corresponding to the number of tones of the multitone signal and an algebra corresponding to an integer that is prime to each other with respect to the number of tones.

In the multitone signal generation method according to the present disclosure, the initial value calculation unit uses a step of calculating the initial value used for the convergence calculation for reducing the PAPR of the multitone signal, and the waveform data generation unit uses the initial value. The step of generating waveform data showing the waveform of the multitone signal whose PAPR is reduced by executing the convergence operation that was performed, and the multitone signal output unit are the multitone corresponding to the waveform data generated by the waveform data generation unit. The initial value includes a plurality of initial phases corresponding to a plurality of tone signals included in the multitone signal, and the initial value calculation unit performs algebraic calculation using a predetermined mathematical formula. Each of the plurality of initial phases is calculated by executing It includes algebra.

According to the present disclosure, since it is configured as described above, it is possible to generate a low PAPR multitone signal for an arbitrary number of tones.

It is a block diagram which shows the main part of the multitone signal generation apparatus which concerns on Embodiment 1. FIG. It is a block diagram which shows the main part of the waveform data generation part in the multitone signal generation apparatus which concerns on Embodiment 1. FIG. It is explanatory drawing which shows the example of the multitone signal in a frequency domain. It is explanatory drawing which shows the example of the multitone signal in the time domain. It is explanatory drawing which shows the example of the error signal in the time domain. It is explanatory drawing which shows the example of the error signal in a frequency domain. It is explanatory drawing which shows the other example of a multitone signal in a frequency domain. It is explanatory drawing which shows the example of PAPR in a normal multitone signal. It is explanatory drawing which shows the example of PAPR in a low PAPR multitone signal. It is a block diagram which shows the hardware composition of the main part of the multitone signal generation apparatus which concerns on Embodiment 1. FIG. It is a block diagram which shows the other hardware configuration of the main part of the multitone signal generation apparatus which concerns on Embodiment 1. FIG. It is a block diagram which shows the other hardware configuration of the main part of the multitone signal generation apparatus which concerns on Embodiment 1. FIG. It is a flowchart which shows the operation of the multitone signal generation apparatus which concerns on Embodiment 1. It is a flowchart which shows the operation of the waveform data generation part in the multitone signal generation apparatus which concerns on Embodiment 1. FIG. It is a flowchart which shows the operation of the waveform data generation part in the multitone signal generation apparatus which concerns on Embodiment 1. FIG. It is a block diagram which shows the main part of the multitone signal generation apparatus which concerns on Embodiment 2. FIG. It is a block diagram which shows the main part of the waveform data generation part in the multitone signal generation apparatus which concerns on Embodiment 2. FIG. It is explanatory drawing which shows the other example of the error signal in a frequency domain. It is explanatory drawing which shows the other example of a multitone signal in a frequency domain. It is a flowchart which shows the operation of the multitone signal generation apparatus which concerns on Embodiment 2. It is a flowchart which shows the operation of the waveform data generation part in the multitone signal generation apparatus which concerns on Embodiment 2. It is a flowchart which shows the operation of the waveform data generation part in the multitone signal generation apparatus which concerns on Embodiment 2. It is a block diagram which shows the main part of the multitone signal generation apparatus which concerns on Embodiment 3. FIG. It is a block diagram which shows the main part of the waveform data generation part in the multitone signal generation apparatus which concerns on Embodiment 3. FIG. It is explanatory drawing which shows the example of the magnification in the 8th processing of each time about the amplitude of each tone signal. It is explanatory drawing which shows the other example of a multitone signal in a frequency domain. It is explanatory drawing which shows the other example of a multitone signal in a frequency domain. It is a flowchart which shows the operation of the multitone signal generation apparatus which concerns on Embodiment 3. It is a flowchart which shows the operation of the waveform data generation part in the multitone signal generation apparatus which concerns on Embodiment 3. FIG. It is a flowchart which shows the operation of the waveform data generation part in the multitone signal generation apparatus which concerns on Embodiment 3. FIG. It is explanatory drawing which shows the other example of the magnification in the 8th processing of each time about the amplitude of each tone signal. It is a block diagram which shows the main part of the multitone signal generation apparatus which concerns on Embodiment 4. FIG. It is a block diagram which shows the main part of the waveform data generation part in the multitone signal generation apparatus which concerns on Embodiment 4. FIG. It is a flowchart which shows the operation of the multitone signal generation apparatus which concerns on Embodiment 4. It is a flowchart which shows the operation of the waveform data generation part in the multitone signal generation apparatus which concerns on Embodiment 4. It is a flowchart which shows the operation of the waveform data generation part in the multitone signal generation apparatus which concerns on Embodiment 4.

Hereinafter, in order to explain this disclosure in more detail, a mode for carrying out this disclosure will be described in accordance with the attached drawings.

Embodiment 1.
FIG. 1 is a block diagram showing a main part of the multitone signal generation device according to the first embodiment. FIG. 2 is a block diagram showing a main part of a waveform data generation unit in the multitone signal generation device according to the first embodiment. The multitone signal generator according to the first embodiment will be described with reference to FIGS. 1 and 2.

As shown in FIG. 1, the multitone signal generation device 100 includes an initial value calculation unit 1, a waveform data generation unit 2, and a multitone signal output unit 3. As shown in FIG. 2, the waveform data generation unit 2 includes a first processing unit 11, a second processing unit 12, a third processing unit 13, a fourth processing unit 14, and a fifth processing unit 15.

The multitone signal MS includes M tone signals TS ₁ to TS _M. That is, the number of tones of the multitone signal MS is M. Here, M is an integer of 2 or more. Hereinafter, the reference numeral “k” may be used for the index corresponding to each tone signal TS. That is, the index k can indicate an individual integer value out of M integer values (1 to M).

The initial value calculation unit 1 acquires a value indicating the number of tones M. The initial value calculation unit 1 calculates the initial value used for the convergence calculation for reducing the PAPR of the multitone signal MS by using the acquired value. Such initial values include M initial phases θ ₁ to θ _{M corresponding to M tone signals TS 1} to TS _M.

More specifically, the initial value calculation unit 1 calculates each of the _{M initial phases θ 1} to θ M by executing algebraic calculation using the following equation (1_1). Alternatively, the initial value calculation unit 1 calculates each of the _{M initial phases θ 1} to θ M by executing algebraic calculation using the following equation (1_2). That is, the initial value calculation unit 1 calculates each initial phase θ _k by executing such algebraic calculation.

M in each of the equations (1_1) and (1_2) indicates an algebra corresponding to the number of tones M. Further, r in each of the equations (1_1) and (1_1) indicates an algebra corresponding to the integer r for the integer r which is relatively prime with respect to the tone number M. Further, k in each of the equations (1_1) and (1_2) indicates an algebra corresponding to the index k.

That is, each of the equations (1_1) and (1_2) includes an algebra corresponding to the number of tones M, and also includes an algebra corresponding to the integer r. Further, each of the equations (1_1) and (1_2) includes an algebra corresponding to the index k.

If the number of tones M is an odd number, the integer r is an even number. On the other hand, when the number of tones M is an even number, the integer r is an odd number.

The waveform data generation unit 2 uses the initial value calculated by the initial value calculation unit 1 to execute a convergence operation for reducing the PAPR of the multitone signal MS. As a result, the waveform data generation unit 2 generates data (hereinafter referred to as “waveform data”) WD indicating the waveform of the multitone signal MS with reduced PAPR.

Here, the convergence operation in the waveform data generation unit 2 repeatedly executes a plurality of processes. The plurality of processes are a process executed by the first processing unit 11 (hereinafter referred to as "first processing"), a processing executed by the second processing unit 12 (hereinafter referred to as "second processing"), and a first. 3 A process executed by the processing unit 13 (hereinafter referred to as "third process"), a process executed by the fourth processing unit 14 (hereinafter referred to as "fourth process"), and executed by the fifth processing unit 15. It includes a process (hereinafter referred to as "fifth process").

More specifically, the convergence operation in the waveform data generation unit 2 executes the first process, the second process, the third process, the fourth process, and the fifth process N times. Here, N is an integer of 2 or more. Hereinafter, the first process, the second process, the third process, the fourth process, and the fifth process will be described.

The first process uses the M amplitude _A 1 ~ _{A M} which correspond to the M tone signal _TS 1 ~ TS _M, and, using the M initial phase theta ₁ ~ theta _M, in the frequency domain It includes a process of setting the multitone signal MS_f. As a result, the frequency domain waveform (that is, the frequency spectrum) of the multitone signal MS is set. A Fourier transform is used to set such a frequency spectrum. In the first processing each time of the first process N times, each of the M amplitude A _{1 ~} A _M, a predetermined value (e.g. 1) are used. _{On the other hand, in each of the M initial phases θ 1} to θ M, the values calculated by the initial value calculation unit 1 are used in the first processing of the first of the N first processes.

FIG. 3 shows an example of a multitone signal MS_f in the frequency domain. More specifically, FIG. 3 shows an example of the multitone signal MS_f set in the first first process of the N first processes. In the example shown in FIG. 3, M = 5.

The second process includes a process of converting the multitone signal MS_f set in the first process into the multitone signal MS_t in the time domain. As a result, the frequency domain waveform (that is, the frequency spectrum) of the multitone signal MS is converted into the time domain waveform (more specifically, the power waveform) of the multitone signal MS. An inverse Fourier transform is used for such a transformation.

FIG. 4 shows an example of the multitone signal MS_t in the time domain. More specifically, FIG. 4 shows an example of the multitone signal MS_t converted in the first second process of the N second processes. In the figure, S indicates a predetermined reference value.

The third process includes a process of calculating the difference value between the value of the multitone signal MS_t converted in the second process and the reference value S. Further, the third process includes a process of calculating the error signal ES_t in the time domain based on the difference value. As a result, the time domain waveform (more specifically, the power waveform) of the error signal ES is calculated.

FIG. 5 shows an example of the error signal ES_t in the time domain. More specifically, FIG. 5 shows an example of the error signal ES_t calculated in the first third process of the N third processes.

The fourth process includes a process of converting the error signal ES_t calculated in the third process into the error signal ES_f in the frequency domain. As a result, the time domain waveform (more specifically, the power waveform) of the error signal ES is converted into the frequency domain waveform (that is, the frequency spectrum) of the error signal ES.

FIG. 6 shows an example of the error signal ES_f in the frequency domain. More specifically, FIG. 6 shows an example of the error signal ES_f converted in the first fourth process of the N fourth processes. As shown in FIG. 6, the error signal ES_f includes M error signals ES ₁ to ES _{M corresponding to M tone signals TS 1} to TS _M. The M error signals ES ₁ to ES _M each have _M amplitudes B ₁ to BM. The M error signals ES ₁ to ES _M each have _M phases φ ₁ to φ M. In the example shown in FIG. 6, M = 5.

The fifth process includes a process of updating each of the _{M initial phases θ 1} to θ M by the following equation (2). That is, the fifth process includes a process of updating _{each initial phase θ k.}

θ _k ← θ _k- φ _k (2)

_{Here, in θ k} on the right side of the equation (2), the value of the corresponding initial phase θ _{k among the M initial phases θ 1} to θ M in the multitone signal MS_f set in the first process is used. Used. For example, in the first fifth process of the N fifth processes, the corresponding initial phases θ _k of the _{M initial phases θ 1} to θ M in the multitone signal MS_f shown in FIG. 3 The value is used.

_{On the other hand, for φ k} on the right side of the equation (2), the value of the corresponding phase φ _{k among the M phases φ 1} to φ M in the error signal ES_f converted in the fourth process is used. For example, in the first fifth process of the N fifth processes, the values of the corresponding phases φ _{k among the M phases φ 1} to φ _{M in} the error signal ES_f shown in FIG. 6 are used. Be done.

That is, the fifth process, based on the difference value between the phase components (phi _k) of the phase component (theta _k) and error signal ES_f multitone signal MS_f (θ _k -φ _k), the individual initial phase theta _k It includes the process of updating. More specifically, the fifth process, the difference value between the corresponding phase component of the tone signal TS _k (θ _k) and corresponding error signal ES _k phase components _{(φ k) (θ k -φ} k) Based on this, it includes a process of updating _{each initial phase θ k.}

Hereinafter, in the same manner, the first process, the second process, the third process, the fourth process, and the fifth process are repeatedly executed. However, in the first processing of each of the second and subsequent times, the updated values in the previous fifth processing are used for each of the _{M initial phases θ 1} to θ M. For example, in the first process of the second time, the updated values in the fifth process of the first time are used for each of the _{M initial phases θ 1} to θ M.

FIG. 7 shows an example of the multitone signal MS_f set in the first processing of the second time. In the example shown in FIG. 7, M = 5. _{However, θ 1} to θ ₅ in FIG. 7 indicate _{the initial phases θ 1} to θ ₅ before the update in the first fifth process. That is, θ ₁ to θ ₅ in FIG. 7 correspond to the values calculated by the initial value calculation unit 1.

By executing such a convergence operation, the PAPR of the multitone signal MS is reduced. _{More specifically, the individual initial phases θ k} converge to a value such that the PAPR of the multitone signal MS is reduced. As a result, a low PAPR multitone signal is realized.

FIG. 8 shows an example of PAPR in the multitone signal MS_t corresponding to _{the initial phases θ 1} to θ _M calculated by the initial value calculation unit 1. On the other hand, FIG. 9 shows an example of PAPR in the multitone signal MS_t corresponding to _{the initial phases θ 1} to θ _M after the update in the fifth process of the Nth time. As shown in FIGS. 8 and 9, the PAPR of the multitone signal MS after the execution of the convergence operation is reduced as compared with the PAPR of the multitone signal MS before the execution of the convergence operation.

When the convergence calculation is completed, the waveform data generation unit 2 executes the same process as the first process by using the _{updated initial phases θ 1} to θ _{M in the fifth process of the Nth time.} Next, the waveform data generation unit 2 executes the same processing as the second processing. As a result, the time domain waveform of the multitone signal MS corresponding to _{the initial phases θ 1} to θ _M after the update in the fifth process of the Nth time is generated. The waveform data generation unit 2 generates data (that is, waveform data) WD indicating the time domain waveform.

The multitone signal output unit 3 acquires the waveform data WD generated by the waveform data generation unit 2. The multitone signal output unit 3 outputs the multitone signal MS corresponding to the acquired waveform data WD. As a result, a low PAPR multitone signal is output.

Here, the waveform data WD generated by the waveform data generation unit 2 is digital data. On the other hand, the multitone signal MS output by the multitone signal output unit 3 is an analog signal. That is, the multitone signal output unit 3 receives the input of digital data and outputs the analog signal corresponding to the input digital data.

In this way, the main part of the multitone signal generation device 100 is configured.

Hereinafter, the functions of the initial value calculation unit 1 may be collectively referred to as "initial value calculation function". Further, the reference numeral of "F1" may be used for the initial value calculation function. Further, the functions of the waveform data generation unit 2 may be collectively referred to as a "waveform data generation function". Further, the reference numeral of "F2" may be used for the waveform data generation function. Further, the functions of the multitone signal output unit 3 may be collectively referred to as "multitone signal output function". Further, the reference numeral of "F3" may be used for the multitone signal output function.

Next, the hardware configuration of the main part of the multitone signal generator 100 will be described with reference to FIGS. 10 to 12.

As shown in FIG. 10, the multitone signal generator 100 includes a processor 21, a memory 22, and a digital-to-analog conversion circuit (hereinafter referred to as “DAC”) 23. The memory 22 stores programs corresponding to a plurality of functions (including an initial value calculation function and a waveform data generation function) F1 and F2. The processor 21 reads and executes the program stored in the memory 22. As a result, a plurality of functions F1 and F2 are realized. Further, the multitone signal output function F3 is realized by the DAC23.

Alternatively, as shown in FIG. 11, the multitone signal generation device 100 includes a processing circuit 24 and a DAC 23. The processing circuit 24 executes processing corresponding to a plurality of functions F1 and F2. As a result, a plurality of functions F1 and F2 are realized. Further, the multitone signal output function F3 is realized by the DAC23.

Alternatively, as shown in FIG. 12, the multitone signal generator 100 includes a processor 21, a memory 22, a processing circuit 24, and a DAC 23. A program corresponding to a part of the plurality of functions F1 and F2 is stored in the memory 22. The processor 21 reads and executes the program stored in the memory 22. As a result, some of these functions are realized. Further, the processing circuit 24 executes processing corresponding to the remaining functions of the plurality of functions F1 and F2. As a result, such residual functions are realized. Further, the multitone signal output function F3 is realized by the DAC23.

The processor 21 is composed of one or more processors. As the individual processor, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), a microprocessor, a microprocessor, or a DSP (Digital Signal Processor) is used.

The memory 22 is composed of one or more non-volatile memories. Alternatively, the memory 22 is composed of one or more non-volatile memories and one or more volatile memories. That is, the memory 22 is composed of one or more memories. The individual memory uses, for example, a semiconductor memory, a magnetic disk, an optical disk, a magneto-optical disk, a magnetic tape, or a magnetic drum. More specifically, each volatile memory uses, for example, a RAM (Random Access Memory). The individual non-volatile memories include, for example, a ROM (Read Only Memory), a flash memory, an EPROM (Erasable Programmable Read Only Memory), an EEPROM (Electrically Erasable Primory) drive, a hard disk drive A compact disc, a DVD (Digital Versaille Disc), a Blu-ray disc, or a mini disc is used.

The processing circuit 24 is composed of one or more digital circuits. Alternatively, the processing circuit 24 is composed of one or more digital circuits and one or more analog circuits. That is, the processing circuit 24 is composed of one or more processing circuits. The individual processing circuits are, for example, ASIC (Application Specific Integrated Circuit), PLD (Programmable Logic Device), FPGA (Field Programmable Gate Array), System LSI (Sy), and System (Sy). Is.

Here, when the processor 21 is composed of a plurality of processors, the correspondence between the plurality of functions F1 and F2 and the plurality of processors is arbitrary. That is, each of the plurality of processors may read and execute a program corresponding to one or more corresponding functions among the plurality of functions F1 and F2. Alternatively, the processor 21 may include a dedicated processor corresponding to each of the plurality of functions F1 and F2.

Further, when the memory 22 is composed of a plurality of memories, the correspondence between the plurality of functions F1 and F2 and the plurality of memories is arbitrary. That is, each of the plurality of memories may store a program corresponding to one or more corresponding functions among the plurality of functions F1 and F2. Alternatively, the memory 22 may include a dedicated memory corresponding to each of the plurality of functions F1 and F2.

Further, when the processing circuit 24 is composed of a plurality of processing circuits, the correspondence between the plurality of functions F1 and F2 and the plurality of processing circuits is arbitrary. That is, each of the plurality of processing circuits may execute the processing corresponding to one or more corresponding functions among the plurality of functions F1 and F2. Alternatively, the processing circuit 24 may include a dedicated processing circuit corresponding to each of the plurality of functions F1 and F2.

Next, the operation of the multitone signal generation device 100 will be described with reference to the flowchart shown in FIG.

First, the initial value calculation unit 1 calculates each of the _{M initial phases θ 1} to θ M by executing an algebraic calculation using the equation (1_1) or the equation (1_2). That is, the initial value calculation unit 1 calculates each initial phase θ _k (step ST1).

Next, the waveform data generation unit 2 executes a convergence operation for reducing the PAPR of the multitone signal MS by using _{the initial phases θ 1} to θ _{M calculated by the initial value calculation unit 1.} As a result, the waveform data generation unit 2 generates the waveform data WD corresponding to the multitone signal MS with reduced PAPR (step ST2). That is, the waveform data generation unit 2 generates the waveform data WD corresponding to the low PAPR multitone signal.

Next, the multitone signal output unit 3 outputs the multitone signal MS corresponding to the waveform data WD generated by the waveform data generation unit 2 (step ST3). As a result, a low PAPR multitone signal is output.

Next, the operation of the waveform data generation unit 2 will be described with reference to the flowchart shown in FIG. That is, the process executed in step ST2 will be described.

As described above, the waveform data generation unit 2 executes the convergence operation. The convergence operation in the waveform data generation unit 2 executes the first process, the second process, the third process, the fourth process, and the fifth process N times (step ST11).

First, the first processing unit 11 executes the first processing (step ST21). That is, the first processing unit 11 sets the multitone signal MS_f in the frequency domain using _{the initial phases θ 1} to θ _{M calculated by the initial value calculation unit 1.} At this time, each of the M amplitude _A 1 ~ _{A M,} a predetermined value (e.g. 1) are used.

Next, the second processing unit 12 executes the second processing (step ST22). As a result, the multitone signal MS_f set in step ST11 is converted into the multitone signal MS_t in the time domain.

Next, the third processing unit 13 executes the third processing (step ST23). As a result, the error signal ES_t in the time domain is calculated. The error signal ES_t is based on the difference value between the value of the multitone signal MS_t converted in step ST22 and the reference value S.

Next, the fourth processing unit 14 executes the fourth processing (step ST24). As a result, the error signal ES_t calculated in step ST23 is converted into the error signal ES_f in the frequency domain.

Next, the fifth processing unit 15 executes the fifth processing (step ST25). That is, the fifth processing unit 15 updates _{each initial phase θ k according to the equation (2).} As a result, each of the M initial phases θ ₁ to θ _M is updated.

When these processes are executed N times, the convergence operation ends. Next, the waveform data generation unit 2 generates waveform data WD (step ST12). The generated waveform data WD shows the time domain waveform of the multitone signal MS corresponding to _{the initial phases θ 1} to θ _M after the update in the fifth process (step ST25) of the Nth time.

Next, the effect of using the multitone signal generation device 100 will be described.

First, in the multitone signal generation device 100, each initial phase θ _k is calculated by algebraic calculation. Further, the mathematical formula (that is, the formula (1_1) or the formula (1_2)) used in the algebraic calculation includes an algebra corresponding to the tone number M. This makes it possible to easily calculate the _{individual initial phase θ k} regardless of the number of tones M. Further, by using the calculated initial phase θ _k in the convergence calculation, a low PAPR multitone signal can be generated regardless of the number of tones M. That is, a low PAPR multitone signal can be generated for an arbitrary number of tones M.

Secondly, the mathematical formula used for the algebraic calculation in the initial value calculation unit 1 includes the algebra corresponding to the integer r. As a result, not only a value different from PBC _{can be used for the initial phases θ 1} to θ _M , but also a value different from the Newman phase can be used for the initial phases θ ₁ to θ _M. That is, it is possible to use a δk different values in the following references 1 to the individual initial phase theta _k.

[Reference 1]
Japanese Unexamined Patent Publication No. 2000-254118

Next, a modification of the multitone signal generation device 100 will be described.

As described above, the convergence operation in the waveform data generation unit 2 executes the first process, the second process, the third process, the fourth process, and the fifth process N times. The waveform data generation unit 2 may execute the convergence operation once. Alternatively, the waveform data generation unit 2 may execute the convergence operation L times. Here, L is an integer of 2 or more.

When the waveform data generation unit 2 executes the convergence operation L times, the first process, the second process, the third process, the fourth process, and the fifth process are executed N × L times. In this case, in the first first process of each of the second and subsequent convergence operations, the updated initial phases θ ₁ to θ _M in the Nth fifth process of the previous convergence operation are used. Further, the waveform data generation unit 2 generates the waveform data WD when the Lth convergence calculation is completed. The generated waveform data WD shows the time domain waveform of the multitone signal MS corresponding to the _{updated initial phases θ 1} to θ _M in the Nth fifth process in the Lth convergence operation. ..

As described above, the multitone signal generation device 100 according to the first embodiment uses the initial value calculation unit 1 for calculating the initial value used for the convergence calculation for reducing the PAPR of the multitone signal MS, and the initial value. Corresponds to the waveform data generation unit 2 that generates the waveform data WD showing the waveform of the multitone signal MS whose PAPR is reduced by executing the convergence calculation used, and the waveform data WD generated by the waveform data generation unit 2. A multi-tone signal output unit 3 that outputs a multi-tone signal MS is provided, and the initial value is M initial phases θ ₁ to _{corresponding to M tone signals TS 1} to TS _{M included in the multi-tone signal MS.} Including θ _{M , the initial value calculation unit 1 calculates each of the M initial phases θ 1} to θ M by executing an algebraic calculation using a predetermined mathematical formula, and the mathematical formula is a multitone signal. Includes an algebra corresponding to the MS tone number M. This makes it possible to easily calculate the individual initial phase θ _k. Further, a low PAPR multitone signal can be generated for an arbitrary number of tones M.

Further, the mathematical formula includes an algebra corresponding to an integer r that is relatively prime with respect to the number of tones M. As a result, not only a value different from PBC _{can be used for the initial phases θ 1} to θ _M , but also a value different from the Newman phase can be used for the initial phases θ ₁ to θ _M.

Further, the formula is a _{θ k = (2π / M)} * {(k-1) 2/2} * r. Thereby, each initial phase θ _k can be calculated using the equation (1_1).

The mathematical formula is θ _k = (2π / M) * {k (k-1) / 2} * r. Thereby, each initial phase θ _k can be calculated using the equation (1_2).

Further, the convergence operation repeatedly executes a plurality of processes, and the plurality of processes include a process of updating each of the _{M initial phases θ 1} to θ M. Thereby, for example, the convergence operation in the waveform data generation unit 2 can be realized based on the flowchart shown in FIG. That is, the reduction of PAPR in the multitone signal MS can be realized by the convergence of the values of the individual initial phases θ _k.

Further, the convergence operation executes the first process, the second process, the third process, the fourth process, and the fifth process N times, and the first process performs M initial phases θ ₁ to θ _M. The second process includes the process of converting the multitone signal MS_f in the frequency domain into the multitone signal MS_t in the time domain, and the third process includes the process of converting the multitone signal MS_f in the frequency domain into the time domain. Including the process of calculating the error signal ES_t in the time domain by calculating the difference value between the value of the multitone signal MS_t and the predetermined reference value S in the fourth process, the fourth process is the error signal ES_t in the time domain in the frequency domain. The fifth process includes a process of converting to the error signal ES_f, and the fifth process is a difference value (θ _{k ) between the phase component (θ k ) of the multitone signal MS_f in the frequency domain and the phase component (φ k} ) of the error signal ES_f in the frequency domain. It includes a process of updating each of the _M initial phases θ ₁ to θ _{M based on −φ k).} As a result, the convergence operation in the waveform data generation unit 2 can be realized based on the flowchart shown in FIG.

Further, in the multitone signal generation method according to the first embodiment, the initial value calculation unit 1 calculates the initial value used for the convergence calculation for reducing the PAPR of the multitone signal MS, and the waveform data generation. The step ST2 in which the unit 2 generates the waveform data WD showing the waveform of the multitone signal MS whose PAPR is reduced by executing the convergence operation using the initial value, and the multitone signal output unit 3 generate the waveform data. The step ST3 for outputting the multitone signal MS corresponding to the waveform data WD generated by the unit 2 is provided, and the initial value corresponds to the _{M tone signals TS 1} to TS M included in the multitone signal MS. includes M initial phase theta _{1 ~} theta _M, initial value calculating section 1 is for computing the each of the M initial phase theta _{1 ~} theta _M by performing the algebraic calculation using a predetermined formula Yes, the formula includes an algebra corresponding to the tone number M of the multitone signal MS. This makes it possible to easily calculate the individual initial phase θ _k. Further, a low PAPR multitone signal can be generated for an arbitrary number of tones M.

Embodiment 2.
FIG. 15 is a block diagram showing a main part of the multitone signal generation device according to the second embodiment. FIG. 16 is a block diagram showing a main part of a waveform data generation unit in the multitone signal generation device according to the second embodiment. The multitone signal generation apparatus according to the second embodiment will be described with reference to FIGS. 15 and 16.

In FIG. 15, the same blocks as those shown in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted. Further, in FIG. 16, the same blocks as those shown in FIG. 2 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 15, the multitone signal generation device 100a includes an initial value calculation unit 1, a waveform data generation unit 2a, and a multitone signal output unit 3. As shown in FIG. 16, the waveform data generation unit 2a includes a first processing unit 11, a second processing unit 12, a third processing unit 13, a fourth processing unit 14, and a fifth processing unit 15a. In addition to this, the waveform data generation unit 2a includes the sixth processing unit 16 and the seventh processing unit 17.

That is, the convergence operation in the waveform data generation unit 2a includes a first process, a second process, a third process, a fourth process, and a fifth process. In addition to this, the convergence operation in the waveform data generation unit 2a is a process executed by the sixth processing unit 16 (hereinafter referred to as “sixth processing”) and a processing executed by the seventh processing unit 17 (hereinafter referred to as “the sixth processing”). 7 processing ") is included. Hereinafter, the convergence operation in the waveform data generation unit 2a will be described focusing on a portion different from the convergence operation in the waveform data generation unit 2.

The sixth processing unit 16 executes the sixth process when the fourth process of each of the N fourth processes is executed. The sixth process includes a process of generating a pseudo-random number x. Further, the sixth process includes a process of comparing the generated pseudo-random number x with a predetermined threshold value α.

The pseudo-random number x is generated based on a uniform distribution or a standard normal distribution, for example, within the range of the closed interval [0,1]. In this case, the threshold value α is preferably set to a value within the range of 0.5 or more and less than 1. Further, it is more preferable that the threshold value α is set to a value within the range of 0.9 or more and less than 1. The reason for this will be described later.

When the generated pseudo-random number x is a value less than the threshold value α, the fifth processing unit 15a executes the same fifth processing as the fifth processing executed by the fifth processing unit 15. That is, the fifth processing unit 15a updates each of the _{M initial phases θ 1} to θ M by the equation (2) described in the first embodiment.

The seventh processing unit 17 executes the seventh processing when the generated pseudo-random number x has a value equal to or higher than the threshold value α. The seventh process includes a process of updating each of the _{M initial phases θ 1} to θ M by the following equation (3).

θ _k ← θ _k- βφ _k (3)

Here, β is a predetermined constant. β is set to a non-zero value and is set to a non-one value (β ≠ 0, β ≠ 1). That is, the seventh process, the difference value between the phase component of the multi-tone signal MS_f (θ _k) and error signal ES_f phase components (phi _k) is constant multiple values _{(βφ k) (θ k -βφ} k) It includes a process of updating each initial phase θ _{k based on.} More specifically, the seventh process, the corresponding tone signal TS _k phase components (theta _k) and a phase component (phi _k) is a constant multiplied by the value of the corresponding error signal ES _k (βφ _k) It includes a process of updating each initial phase θ _k based on the difference value (θ _{k −} β φ _k).

As described above, the convergence operation in the waveform data generation unit 2a repeatedly executes a plurality of processes. More specifically, in the convergence operation in the waveform data generation unit 2a, the first process, the second process, the third process, the fourth process and the sixth process are executed N times, and the fifth process or the seventh process is performed. It is selectively executed N times. In other words, the convergence operation in the waveform data generation unit 2a executes the first process, the second process, the third process, the fourth process, the sixth process, the fifth process, or the seventh process N times. In the first processing of each of the second and subsequent times, the updated values in the previous fifth processing or seventh processing are used for each of the _{M initial phases θ 1} to θ M. Further, the waveform data WD shows the time domain waveform of the multitone signal MS corresponding to _{the initial phases θ 1} to θ _M after the update in the fifth process or the seventh process of the Nth time.

Note that the threshold value α may be a value preset by the user. Further, a value preset by the user may be used for the constant β. In this case, the waveform data generation unit 2a may acquire the set threshold value α and also acquire the set constant β (see FIG. 15).

FIG. 17 shows an example of the error signal ES_f corresponding to the constant-multiplied phase (βφ _k). In the example shown in FIG. 17, M = 5.

FIG. 18 shows an example of the multitone signal MS_f corresponding to the updated initial phases θ ₁ to θ _{M in the seventh process.} In the example shown in FIG. 18, M = 5. _{However, θ 1} to θ ₅ in FIG. 18 indicate _{the initial phases θ 1} to θ ₅ before the update in the seventh process. That is, θ ₁ to θ ₅ in FIG. 18 correspond to the values calculated by the initial value calculation unit 1.

In this way, the main part of the multitone signal generation device 100a is configured.

Hereinafter, the functions of the waveform data generation unit 2a may be collectively referred to as "waveform data generation function". Further, the reference numeral of "F2a" may be used for the waveform data generation function.

The hardware configuration of the main part of the multitone signal generation device 100a is the same as that described with reference to FIGS. 10 to 12 in the first embodiment. Therefore, detailed description thereof will be omitted.

That is, the multitone signal generation device 100a has a plurality of functions (including an initial value calculation function and a waveform data generation function) F1 and F2a, and also has a multitone signal output function F3. .. Each of the plurality of functions F1 and F2a may be realized by the processor 21 and the memory 22, or may be realized by the processing circuit 24. Further, the multitone signal output function F3 may be realized by the DAC23.

Here, the processor 21 may include a dedicated processor corresponding to each of the plurality of functions F1 and F2a. Further, the memory 22 may include a dedicated memory corresponding to each of the plurality of functions F1 and F2a. Further, the processing circuit 24 may include a dedicated processing circuit corresponding to each of the plurality of functions F1 and F2a.

Next, the operation of the multitone signal generation device 100a will be described with reference to the flowchart shown in FIG. In FIG. 19, the same steps as those shown in FIG. 13 are designated by the same reference numerals and the description thereof will be omitted.

First, the process of step ST1 is executed.

Next, the waveform data generation unit 2a executes a convergence operation for reducing the PAPR of the multitone signal MS by using _{the initial phases θ 1} to θ _{M calculated by the initial value calculation unit 1.} As a result, the waveform data generation unit 2a generates the waveform data WD corresponding to the multitone signal MS with reduced PAPR (step ST2a).

Next, the process of step ST3 is executed.

Next, the operation of the waveform data generation unit 2a will be described with reference to the flowchart shown in FIG. That is, the process executed in step ST2a will be described. In FIG. 20, the same steps as those shown in FIG. 14 are designated by the same reference numerals and the description thereof will be omitted.

As described above, the waveform data generation unit 2a executes the convergence operation. The convergence operation in the waveform data generation unit 2a executes the first process, the second process, the third process, the fourth process, the sixth process, the fifth process, or the seventh process N times (step ST11a).

First, the first processing unit 11 executes the first processing (step ST21). Next, the second processing unit 12 executes the second processing (step ST22). Next, the third processing unit 13 executes the third processing (step ST23). Next, the fourth processing unit 14 executes the fourth processing (step ST24).

Next, the sixth processing unit 16 executes the sixth processing (steps ST26_1 and ST26_2). As a result, a pseudo-random number x is generated (step ST26_1). Further, the generated pseudo-random number x is compared with the threshold value α (step ST26_2).

When the pseudo-random number x is a value less than the threshold value α (step ST26_2 “YES”), the fifth processing unit 15a executes the fifth processing (step ST25a). That is, the fifth processing unit 15a updates _{each initial phase θ k according to the equation (2).} As a result, each of the M initial phases θ ₁ to θ _M is updated.

On the other hand, when the pseudo-random number x is a value equal to or higher than the threshold value α (step ST26_2 “NO”), the seventh processing unit 17 executes the seventh processing (step ST27). That is, the seventh processing unit 17 updates _{each initial phase θ k by the equation (3).} As a result, each of the M initial phases θ ₁ to θ _M is updated.

When these processes are executed N times, the convergence operation ends. Next, the waveform data generation unit 2a generates the waveform data WD (step ST12). The generated waveform data WD is the time domain waveform of the multitone signal MS corresponding to the _{updated initial phases θ 1} to θ _M in the fifth process or the seventh process (step ST25a or step ST27) of the Nth time. It shows.

Next, the effect of using the multitone signal generation device 100a will be described.

In the multitone signal generation device 100, the individual initial phase θ _k is updated N times by the convergence operation, and the update method in the N times update is constant. That is, each of the N updates is due to the fifth process. Therefore, when the values of the individual initial phases θ _k converge, the converged values may become the values corresponding to the local solution. In other words, the convergence operation can fall into a local solution.

On the other hand, in the multitone signal generation device 100a, the update method in each update of the N times is changed with a probability corresponding to the threshold value α. That is, the update method can change from the fifth process to the seventh process with a probability corresponding to the threshold value α. As a result, when the values of the individual initial phases θ _k converge, it is possible to prevent the converged values from becoming the values corresponding to the local solution. In other words, it is possible to avoid the occurrence of such a local solution.

Here, when the threshold value α is set to a small value (for example, a value less than 0.5), the probability that the seventh process is executed is higher than the probability that the fifth process is executed in each update. It gets higher. In other words, in each update, the probability that the fifth process is executed is lower than the probability that the seventh process is executed. This reduces the effect of avoiding the occurrence of local solutions. Therefore, as described above, it is preferable that the threshold value α is set to a value within the range of, for example, 0.5 or more and less than 1.

Then, by reducing the probability that the seventh process is executed at each update to 10% or less, the effect of avoiding the occurrence of a local solution can be improved. This is a rule of thumb. Therefore, as described above, it is more preferable that the threshold value α is set to a value within the range of, for example, 0.9 or more and less than 1.

Next, a modified example of the multitone signal generation device 100a will be described.

As the multitone signal generation device 100a, various modifications similar to those described in the first embodiment can be adopted. For example, the waveform data generation unit 2a may execute the convergence operation shown in FIG. 20 L times.

When the waveform data generation unit 2a executes the convergence operation L times, the first process, the second process, the third process, the fourth process, and the sixth process are executed N × L times, and the fifth process or the fifth process is performed. 7 The process is selectively executed N × L times. In this case, in the first first process of each of the second and subsequent convergence operations, the initial phase after the update in the Nth fifth process or the seventh process in the previous convergence operation θ ₁ to θ _M. Is used. Further, the waveform data generation unit 2a generates the waveform data WD when the Lth convergence calculation is completed. The generated waveform data WD is the time domain waveform of the multitone signal MS corresponding to the _{updated initial phases θ 1} to θ _M in the Nth fifth process or the seventh process in the Lth convergence operation. It shows.

As described above, in the multitone signal generation device 100a according to the second embodiment, the convergence operation repeatedly executes a plurality of processes, and the plurality of processes include a process of generating a pseudo-random number x. The plurality of processes include a process of updating each of the _{M initial phases θ 1} to θ M by different update methods according to the pseudo-random number x. This makes it possible to avoid the occurrence of a local solution in the convergence operation. In other words, when the values of the individual initial phases θ _k converge, the converged values can be set to the values corresponding to the global solution. As a result, the PAPR of the multitone signal MS can be further reduced.

Further, the convergence operation executes the first process, the second process, the third process, the fourth process, the sixth process, the fifth process, or the seventh process N times, and the first process is M pieces. The process of setting the multitone signal MS_f in the frequency domain using the initial phases θ ₁ to θ _M is included, and the second process includes the process of converting the multitone signal MS_f in the frequency domain into the multitone signal MS_t in the time domain. The third process includes a process of calculating the error signal ES_t in the time domain by calculating the difference value between the value of the multitone signal MS_t in the time domain and the predetermined reference value S, and the fourth process is the process of calculating the error signal ES_t in the time domain. The sixth process includes a process of converting the error signal ES_t in the frequency domain into an error signal ES_f in the frequency domain, the sixth process includes a process of generating a pseudo random number x, and a process of comparing the pseudo random number x with a predetermined threshold value α, and the fifth process includes a process of comparing the pseudo random number x with a predetermined threshold value α. When the pseudo random number x is a value less than the threshold value α, the difference value (θ _k − _{) between the phase component (θ k ) of the multitone signal MS_f in the frequency domain and the phase component (φ k} ) of the error signal ES_f in the frequency domain. _{The seventh process includes the process of updating each of the M} initial phases θ ₁ to θ M based on φ _k ), and the seventh process is the multitone signal MS in the frequency domain when the pseudo random number x is a value equal to or greater than the threshold α. phase component (theta _k) and the difference value (θ _k -βφ _k) M-number of initial phase theta ₁ based on the phase component of the error signal ES_f in the frequency domain (phi _k) is a constant multiple values (βφ _k) It includes a process of updating each of ~ θ _M. Thereby, the convergence operation in the waveform data generation unit 2a can be realized based on the flowchart shown in FIG.

Embodiment 3.
FIG. 21 is a block diagram showing a main part of the multitone signal generation device according to the third embodiment. FIG. 22 is a block diagram showing a main part of a waveform data generation unit in the multitone signal generation device according to the third embodiment. The multitone signal generation device according to the third embodiment will be described with reference to FIGS. 21 and 22.

In FIG. 21, the same blocks as those shown in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted. Further, in FIG. 22, the same blocks as those shown in FIG. 2 are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 21, the multitone signal generation device 100b includes an initial value calculation unit 1, a waveform data generation unit 2b, and a multitone signal output unit 3. As shown in FIG. 22, the waveform data generation unit 2b includes a first processing unit 11, a second processing unit 12, a third processing unit 13, a fourth processing unit 14, and a fifth processing unit 15. In addition to this, the waveform data generation unit 2b includes the eighth processing unit 18.

That is, the convergence operation in the waveform data generation unit 2b includes a first process, a second process, a third process, a fourth process, and a fifth process. In addition to this, the convergence operation in the waveform data generation unit 2b includes a process executed by the eighth process unit 18 (hereinafter referred to as “eighth process”). Hereinafter, the convergence operation in the waveform data generation unit 2b will be described focusing on a portion different from the convergence operation in the waveform data generation unit 2.

Hereinafter, the sign of "i" may be used for the index corresponding to each of the N times of processing in the convergence operation. That is, the index i can indicate an individual integer value out of N integer values (1 to N).

In the eighth process, N × M values (hereinafter referred to as “magnification values”) corresponding to N × M _{magnifications (1 + γ 1,1} ) to (1 + γ _{N, M ) γ 1,1} to γ _{N, M} is used. The individual magnification values γ _{i and k correspond to the kth} tone signal TS _{k of the M} tone signals TS ₁ to TS M, and the i-th of the N times eighth processing. It corresponds to the eighth process of the times. That is, each magnification value gamma _{i, k} is intended to correspond to any one of the tone signal TS _k of the M tone signal _TS 1 ~ TS _M, and the eighth process N times It corresponds to any one of the eighth processes.

Here, it is preferable that the magnification values γ _{i, k} of each of the N × M magnification values γ _1,1 to γ _{N, M} are set to different values. However, N × M pieces of the part of the magnification value gamma _{i, k} of the magnification value γ _{1,1 ~} γ _{N, M,} the two magnifications of such part of the magnification value gamma _{i, k} The values γ _{i and k} may be set to the same value. The individual magnification values γ _{i and k} are set to non--1 values (γ _{i, k} ≠ -1). This is because the corresponding magnification (1 + γ _{i, k} ) is set to a non-zero value for each magnification value γ _{i, k.}

The eighth processing unit 18 has a data table showing _{N × M magnification values γ 1,1} to γ _{N, M.} Alternatively, when the eighth processing unit 18 executes the eighth processing each time, the eighth processing unit 18 generates M pseudo-random numbers corresponding to the M _{tone signals TS 1} to TS _{M, and corresponds to the generated pseudo-random numbers.} It is used for the magnification values γ _{i and k.}

In the first time the first process of the first processing N times, each of the M amplitude A _{1 ~} A _M, a predetermined value (e.g. 1) are used. Therefore, in the multi-tone signal MS_f set by the 1st first process, an individual amplitude A _k is 1 (see FIG. 3).

The eighth processing unit 18 executes the eighth processing when the first processing of each time is executed. Eighth processing each time using the corresponding magnification value gamma _{i, k} of the N × M pieces of magnification values gamma _{1, 1} ~ gamma _{N, M,} and each of the M amplitude _A 1 ~ _{A M} It includes the process of updating. That is, the eighth process each time is intended to include processing for updating the individual amplitudes A _k according to the following equation (4).

_Ak ← (1 + γ _{i, k} ) _Ak (4)

Further, an eighth process each time are those which comprise a process for generating a multi-tone signal MS_f corresponding to the amplitude A _{1 ~} A _M which is the update. That is, the eighth process each time, for a corresponding first processing multitone signal MS_f set by, is intended to include the processing of the individual amplitude A _k to (1 + γ _{i, k)} times. Thus, for multi-tone signal MS_f set by the corresponding first process, the individual amplitude _{A k} is (1 + γ _{i, k)} multiplied multitone signal MS_f is generated.

FIG. 23 shows an example of individual magnifications (1 + γ _{i, k) in each eighth process.} In the example shown in FIG. 23, N = 3 and M = 5.

FIG. 24 shows an example of the multitone signal MS_f generated in the first eighth process of the N eighth processes. In the example shown in FIG. 24, M = 5. _{However, A 1} to A ₅ in FIG. 24 indicate _{the amplitudes A 1} to A ₅ before the update in the first eighth process. That is, A ₁ to A ₅ in FIG. 24 correspond to 1.

Following the eighth process each time, the second process is executed. In each second process, the multitone signal MS_f generated in the corresponding eighth process is converted into a multitone signal MS_t in the time domain. Then, the third process, the fourth process, and the fifth process are sequentially executed. By executing the fifth process, each initial phase θ _k is updated. Then, the next first process is executed using the initial phases θ ₁ to θ _{M after the update.} However, in the first process each time after the second time, each of the M amplitude A _{1 ~} A _M, the updated value in the eighth process of the previous time is used.

That is, in the first process of the first of the N times of the first process, a predetermined value (for example, 1) is _{used for each amplitude Ak,} and the value calculated by the initial value calculation unit 1 is individually used. Used for the initial phase θ _{k of.} On the other hand, in the first processing of each of the second and subsequent times of the first processing of N times, the updated value in the previous eighth processing is _{used for each amplitude Ak} , and the previous fifth processing. The updated value in is used for _{each initial phase θ k.}

FIG. 25 shows an example of the multitone signal MS_f set in the first processing of the second time. In the example shown in FIG. 25, M = 5. _{However, A 1} to A ₅ in FIG. 25 indicate _{the amplitudes A 1} to A ₅ before the update in the first eighth process. That is, A ₁ to A ₅ in FIG. 25 correspond to 1. _{Further, θ 1} to θ ₅ in FIG. 25 indicate _{the initial phases θ 1} to θ ₅ before the update in the first fifth process. That is, θ ₁ to θ ₅ in FIG. 25 correspond to the values calculated by the initial value calculation unit 1.

As described above, the convergence operation in the waveform data generation unit 2b repeatedly executes a plurality of processes. More specifically, the convergence operation in the waveform data generation unit 2b executes the first process, the eighth process, the second process, the third process, the fourth process, and the fifth process N times.

In this way, the main part of the multitone signal generation device 100b is configured.

Hereinafter, the functions of the waveform data generation unit 2b may be collectively referred to as "waveform data generation function". Further, the reference numeral of "F2b" may be used for the waveform data generation function.

The hardware configuration of the main part of the multitone signal generation device 100b is the same as that described with reference to FIGS. 10 to 12 in the first embodiment. Therefore, detailed description thereof will be omitted.

That is, the multitone signal generation device 100b has a plurality of functions (including an initial value calculation function and a waveform data generation function) F1 and F2b, and also has a multitone signal output function F3. .. Each of the plurality of functions F1 and F2b may be realized by the processor 21 and the memory 22, or may be realized by the processing circuit 24. Further, the multitone signal output function F3 may be realized by the DAC23.

Here, the processor 21 may include a dedicated processor corresponding to each of the plurality of functions F1 and F2b. Further, the memory 22 may include a dedicated memory corresponding to each of the plurality of functions F1 and F2b. Further, the processing circuit 24 may include a dedicated processing circuit corresponding to each of the plurality of functions F1 and F2b.

Next, the operation of the multitone signal generation device 100b will be described with reference to the flowchart shown in FIG. In FIG. 26, the same steps as those shown in FIG. 13 are designated by the same reference numerals and the description thereof will be omitted.

First, the process of step ST1 is executed.

Next, the waveform data generation unit 2b executes a convergence operation for reducing the PAPR of the multitone signal MS by using _{the initial phases θ 1} to θ _{M calculated by the initial value calculation unit 1.} As a result, the waveform data generation unit 2b generates the waveform data WD corresponding to the multitone signal MS with reduced PAPR (step ST2b).

Next, the process of step ST3 is executed.

Next, the operation of the waveform data generation unit 2b will be described with reference to the flowchart shown in FIG. 27. That is, the process executed in step ST2b will be described. In FIG. 27, the same steps as those shown in FIG. 14 are designated by the same reference numerals and the description thereof will be omitted.

As described above, the waveform data generation unit 2b executes the convergence operation. The convergence operation in the waveform data generation unit 2b executes the first process, the eighth process, the second process, the third process, the fourth process, and the fifth process N times (step ST11b).

First, the first processing unit 11 executes the first processing (step ST21). Next, the eighth processing unit 18 executes the eighth processing (step ST28). As a result, the individual amplitudes _Ak are updated by the equation (4). The multi-tone signal MS_f corresponding to the amplitude _A 1 ~ _{A M} which is the update is generated. That is, the individual amplitudes _Ak are multiplied by (1 + γ _{i, k).}

Next, the second processing unit 12 executes the second processing for the multitone signal MS_f generated in step ST28 (step ST22). Next, the third processing unit 13 executes the third processing (step ST23). Next, the fourth processing unit 14 executes the fourth processing (step ST24). Next, the fifth processing unit 15 executes the fifth processing (step ST25).

When these processes are executed N times, the convergence operation ends. Next, the waveform data generation unit 2b generates waveform data WD (step ST12). Waveform data WD which the generated is a multi-tone signal MS corresponding to the amplitude A _{1 ~} A _M updated in the eighth process of the N times (step ST28), the N times of the fifth process (step It shows the time domain waveform of the multitone signal MS corresponding to _{the initial phase θ 1} to θ _M after the update in ST25).

Next, the effect of using the multitone signal generation device 100b will be described.

As described above, the convergence operation in the waveform data generation unit 2b includes _{a process of updating the individual amplitude Ak} (that is, the eighth process) _{in addition to the process of updating the individual initial phase θ k} (that is, the fifth process). It includes. By increasing the types of parameters to be updated in the convergence operation, the effect of reducing PAPR can be improved.

Next, a modification of the multitone signal generation device 100b will be described.

As the multitone signal generation device 100b, various modifications similar to those described in the first embodiment can be adopted. For example, the waveform data generation unit 2b may execute the convergence operation shown in FIG. 27 L times. Hereinafter, the sign of "j" may be used for the index corresponding to each of the L times of convergence operations. That is, the index j can indicate an individual integer value out of L integer values (1 to L).

When the waveform data generation unit 2b executes the convergence operation L times, the first process, the eighth process, the second process, the third process, the fourth process, and the fifth process are executed N × L times. In this case, in the first time first process in each round of convergence calculation after the 2nd, the amplitude A _{1 ~} A _M updated in the eighth process of the N times is used in the preceding convergence calculation, _{The initial phases θ 1} to θ _M after the update in the Nth fifth process in the previous convergence operation are used. Further, the waveform data generation unit 2b generates the waveform data WD when the Lth convergence operation is completed. The generated waveform data WD is a multi-tone signal MS corresponding to the amplitude A _{1 ~} A _M updated in the eighth process of the N times in the convergence calculation of the L times, the L-time convergence calculation The time domain waveform of the multitone signal MS corresponding to _{the initial phase θ 1} to θ _M after the update in the fifth process of the Nth time is shown.

Here, different values may be used for the individual magnification values γ _{i and k for each convergence operation.} In other words, the eighth processing unit 18 has L × N × M _{magnification values γ 1} corresponding to L × N × M _{magnifications (1 + γ 1,1,1} ) to (1 + γ _{L, N, M). , 1, 1} to γ _{L, N, M} may be used. The individual magnification values γ _{j, i, and k correspond to the kth} tone signal TS k of the M tone signals TS ₁ to TS _{M, and} are among the N eighth processes. It corresponds to the eighth process of the i-th time, and corresponds to the j-th convergence operation of the L times of convergence operations. That is, the individual magnification values γ _{j, i, and k} correspond to any one of the _M tone signals TS ₁ to TS M, and the Nth time _{signal TS k.} It corresponds to any one of the eighth processes, and corresponds to any one of the L times of convergence operations.

In the 8th processing of each time in each convergence operation, the 8th processing unit 18 has L × N × M magnification values γ _1,1,1 to γ corresponding magnification values γ _{j among L, N, and M. , i,} with _k, updating each of the M amplitude _a 1 ~ _{a M.} That is, the eighth processing unit 18 updates the individual amplitudes _{A k} according to the following equation (5).

_Ak ← (1 + γ _{j, i, k} ) _Ak (5)

Further, in the eighth process each time at each time of the convergence calculation, the eighth processing unit 18 generates a multi-tone signal MS_f corresponding to the amplitude A _{1 ~} A _M which is the update. That is, the eighth processing unit 18, the multi-tone signal MS_f set by the corresponding first process, the individual amplitude _{A k (1 + γ j,} i, k) is doubled. Thus, for the corresponding multi-tone signal set by the first process of MS_f, individual amplitude _{A k} is _{(1 + γ j, i,} k) multiplied multitone signal MS_f is generated.

FIG. 28 shows an example _{of individual magnifications (1 + γ j, i, k} ) in the eighth process of each time in each convergence operation. In the example shown in FIG. 28, L = 3, N = 3, and M = 5.

Next, another modification of the multitone signal generator 100b will be described.

Eighth processing unit 18, in the eighth processing each time, instead of updating the individual amplitudes A _k by equation (4), be one that updates the individual amplitudes A _k according to the following equation (6) May be. That is, the eighth processing unit 18 may multiply _{each amplitude Ak} by (1-γ _{i, k) in each eighth processing.} In this case, it is preferable that the individual magnification values γ _{i, k} are set to non- _{unique values (γ i, k} ≠ 1).

_Ak ← (1-γ _{i, k} ) _Ak (6)

Or, the eighth processing unit 18, in the eighth process each time at each time of the convergence calculation, instead of the equation (5) to update individual amplitude A _k, each according to the following equation (7) the amplitude A It may be the one that updates _k. That is, the eighth processing unit 18 may multiply _{the individual amplitude Ak} by (1-γ _{j, i, k) in each eighth processing in each convergence operation.} In this case, the individual magnification values γ _{j, i, k} are preferably set to non-unique values (γ _{j, i, k} ≠ 1).

_Ak ← (1-γ _{j, i, k} ) _Ak (7)

As described above, in the multitone signal generation device 100b according to the third embodiment, the convergence operation repeatedly executes a plurality of processes, and the plurality of processes are performed by M tone signals TS ₁ to TS. for M amplitude a _{1 ~} a _M which correspond to _M, comprises the process of updating each of a plurality of amplitude a _{1 ~} a _M, a plurality of process, updates the respective plurality of initial phase theta _k Includes processing to do. This makes it possible to increase the types of parameters to be updated in the convergence operation. As a result, the effect of reducing PAPR can be improved.

Further, the convergence operation executes the first process, the eighth process, the second process, the third process, the fourth process, and the fifth process N times, and the first process is the M tone signal TS ₁ The eighth process includes a process of setting the multitone signal MS_f in the frequency domain using _M amplitudes A ₁ to AM corresponding to ~ TS _M and M initial phases θ ₁ to θ _{M, and the eighth process is N ×.} Of the M magnification values γ _1,1 to γ _{N, M} , the corresponding magnification values γ _{i, k} or L × N × M magnification values γ _1,1,1 to γ _{L, N, M} corresponding magnification value gamma _j, wherein _i, the process of updating each of the M amplitude a _{1 ~} a _M with _k, the second process, a multi-tone multi-tone signal MS_f in the frequency domain in the time domain The third process includes the process of converting to the signal MS_t, and the third process includes the process of calculating the error signal ES_t in the time domain by calculating the difference value between the value of the multitone signal MS_t in the time domain and the predetermined reference value S. The fourth process includes the process of converting the error signal ES_t in the time domain into the error signal ES_f in the frequency domain, and the fifth process includes the phase component (θ _k ) of the multitone signal MS_f in the frequency domain and the error in the frequency domain. including a process of updating each of the M initial phase theta ₁ ~ theta _M based on the difference value between the phase component of the signal _{ES_f (φ k) (θ k} -φ k). Thereby, the convergence operation in the waveform data generation unit 2b can be realized based on the flowchart shown in FIG. 27.

Further, each of the N × M magnification values γ _1,1 to γ _{N, M} or each of the L × N × M magnification values γ _1,1,1 to γ _{L, N, M} is M. It corresponds to the tone signal TS _{k of any one of the} tone signals TS 1 to TS _M , and corresponds to any one of the 8th processes of N times. be. Thus, the eighth process N times, it is possible to occupy different magnification according to the individual amplitude A _k to the 8 per treatment.

Further, the waveform data generation unit 2b executes the convergence operation L times, and each of the magnification values γ _1,1,1 to γ _{L, N, M} of L × N × M converges L times. It corresponds to any one of the operations, the convergence operation. Thus, for L times convergence calculation can be made different magnification according to the individual amplitude A _k for each convergence calculation.

Embodiment 4.
FIG. 29 is a block diagram showing a main part of the multitone signal generation device according to the fourth embodiment. FIG. 30 is a block diagram showing a main part of a waveform data generation unit in the multitone signal generation device according to the fourth embodiment. The multitone signal generation device according to the fourth embodiment will be described with reference to FIGS. 29 and 30.

In FIG. 29, the same blocks as those shown in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted. Further, in FIG. 30, the same blocks as those shown in FIG. 16 are designated by the same reference numerals and the description thereof will be omitted. Further, in FIG. 30, the same blocks as those shown in FIG. 22 are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 29, the multitone signal generation device 100c includes an initial value calculation unit 1, a waveform data generation unit 2c, and a multitone signal output unit 3. As shown in FIG. 30, the waveform data generation unit 2c includes a first processing unit 11, a second processing unit 12, a third processing unit 13, a fourth processing unit 14, and a fifth processing unit 15a. In addition to this, the waveform data generation unit 2c includes the sixth processing unit 16 and the seventh processing unit 17. Further, the waveform data generation unit 2c includes the eighth processing unit 18.

That is, the waveform data generation unit 2c is formed by combining the waveform data generation unit 2a and the waveform data generation unit 2b. The convergence operation in the waveform data generation unit 2c repeatedly executes a plurality of processes. More specifically, in the convergence operation in the waveform data generation unit 2c, the first process, the eighth process, the second process, the third process, the fourth process, and the sixth process are executed N times, and the fifth process or the fifth process is performed. The seventh process is selectively executed N times. In other words, the convergence operation in the waveform data generation unit 2c executes the first process, the eighth process, the second process, the third process, the fourth process, the sixth process, and the fifth process or the seventh process N times. It is a thing.

In this way, the main part of the multitone signal generation device 100c is configured.

Hereinafter, the functions of the waveform data generation unit 2c may be collectively referred to as "waveform data generation function". Further, the reference numeral of "F2c" may be used for the waveform data generation function.

The hardware configuration of the main part of the multitone signal generation device 100c is the same as that described with reference to FIGS. 10 to 12 in the first embodiment. Therefore, detailed description thereof will be omitted.

That is, the multitone signal generation device 100c has a plurality of functions (including an initial value calculation function and a waveform data generation function) F1 and F2c, and also has a multitone signal output function F3. .. Each of the plurality of functions F1 and F2c may be realized by the processor 21 and the memory 22, or may be realized by the processing circuit 24. Further, the multitone signal output function F3 may be realized by the DAC23.

Here, the processor 21 may include a dedicated processor corresponding to each of the plurality of functions F1 and F2c. Further, the memory 22 may include a dedicated memory corresponding to each of the plurality of functions F1 and F2c. Further, the processing circuit 24 may include a dedicated processing circuit corresponding to each of the plurality of functions F1 and F2c.

Next, the operation of the multitone signal generation device 100c will be described with reference to the flowchart shown in FIG. In FIG. 31, the same steps as those shown in FIG. 13 are designated by the same reference numerals and the description thereof will be omitted.

First, the process of step ST1 is executed.

Next, the waveform data generation unit 2c executes a convergence operation for reducing the PAPR of the multitone signal MS by using _{the initial phases θ 1} to θ _{M calculated by the initial value calculation unit 1.} As a result, the waveform data generation unit 2c generates the waveform data WD corresponding to the multitone signal MS with reduced PAPR (step ST2c).

Next, the process of step ST3 is executed.

Next, the operation of the waveform data generation unit 2c will be described with reference to the flowchart shown in FIG. That is, the process executed in step ST2c will be described. In FIG. 32, the same steps as those shown in FIG. 20 are designated by the same reference numerals and the description thereof will be omitted. Further, in FIG. 32, the same steps as those shown in FIG. 27 are designated by the same reference numerals and the description thereof will be omitted.

As described above, the waveform data generation unit 2c executes the convergence operation. The convergence operation in the waveform data generation unit 2c executes the first process, the eighth process, the second process, the third process, the fourth process, the sixth process, the fifth process, or the seventh process N times (. Step ST11c).

First, the first processing unit 11 executes the first processing (step ST21). Next, the eighth processing unit 18 executes the eighth processing (step ST28). Next, the second processing unit 12 executes the second processing (step ST22). Next, the third processing unit 13 executes the third processing (step ST23). Next, the fourth processing unit 14 executes the fourth processing (step ST24). Next, the sixth processing unit 16 executes the sixth processing (steps ST26_1 and ST26_2). When the pseudo-random number x is a value less than the threshold value α (step ST26_2 “YES”), the fifth processing unit 15a executes the fifth processing (step ST25a). On the other hand, when the pseudo-random number x is a value equal to or higher than the threshold value α (step ST26_2 “NO”), the seventh processing unit 17 executes the seventh processing (step ST27).

When these processes are executed N times, the convergence operation ends. Next, the waveform data generation unit 2 generates waveform data WD (step ST12). Waveform data WD which the generated is a multi-tone signal MS corresponding to the amplitude A _{1 ~} A _M updated in the eighth process of the N times (step ST28), the fifth processing or the N-th time It shows the time domain waveform of the multitone signal MS corresponding to _{the initial phase θ 1} to θ _M after the update in 7 processing (step ST25a or step ST27).

As the multitone signal generation device 100c, various modifications similar to those described in the first embodiment can be adopted. Further, as the multitone signal generation device 100c, various modifications similar to those described in the second embodiment can be adopted. Further, as the multitone signal generation device 100c, various modifications similar to those described in the third embodiment can be adopted.

As described above, in the multitone signal generation device 100c according to the fourth embodiment, the convergence operation repeatedly executes a plurality of processes, and the plurality of processes are performed by M tone signals TS ₁ to TS. for M amplitude a _{1 ~} a _M which correspond to _M, comprises the process of updating each of the M amplitude a _{1 ~} a _M, a plurality of processing may include processing for generating a pseudo-random number x, a plurality The processing includes a process of updating each of the _{M initial phases θ 1} to θ M by different update methods according to the pseudo-random number x. Thereby, the PAPR of the multitone signal MS can be further reduced. In addition, the effect of reducing PAPR can be improved.

Further, the convergence operation executes the first process, the eighth process, the second process, the third process, the fourth process, the sixth process and the fifth process or the seventh process N times, and the first process is includes a process of setting a multi-tone signal MS_f in the frequency domain using the M amplitude _a 1 ~ _{a M} and M number of initial phase theta ₁ ~ theta _M corresponding to the M tone signal _TS 1 ~ TS _M In the eighth process, the corresponding magnification values γ _{i, k} or L × N × M magnification values γ _1,1,1 among N × M magnification values γ _1,1 to γ _{N, M are performed.} includes a processing for updating each of the M amplitude a _{1 ~} a _M using gamma _{L, N,} corresponding magnification value gamma _j of _{M, i,} the _k, the second process, the multi-tone in the frequency domain The third process includes a process of converting the signal MS_f into a multitone signal MS_t in the time domain, and the third process is an error in the time domain by calculating the difference value between the value of the multitone signal MS_t in the time domain and the predetermined reference value S. The fourth process includes a process of calculating the signal ES_t, the fourth process includes a process of converting the error signal ES_t in the time domain into the error signal ES_f in the frequency domain, and the sixth process includes a process of generating a pseudo random number x and a pseudo random number x. _{The fifth process includes the phase component (θ k} ) of the multitone signal MS_f in the frequency domain and the error signal in the frequency domain when the pseudo random number x is a value less than the threshold α. includes a processing for updating each of the M initial phase theta ₁ ~ theta _M based on the difference value (θ _k -φ _k) with ES_f phase components (phi _k), seventh process, a pseudo-random number x is the threshold If it is α or more values, the difference value between the multi-tone signal MS_f phase components (theta _k) the value phase component of the error signal ES_f in the frequency domain (phi _k) is a constant multiple (βφ _k) in the frequency domain It includes a process of updating each of the _M initial phases θ ₁ to θ M based on (θ _{k −} β φ _k). As a result, the convergence operation in the waveform data generation unit 2c can be realized based on the flowchart shown in FIG.

Further, each of the N × M magnification values γ _1,1 to γ _{N, M} or each of the L × N × M magnification values γ _1,1,1 to γ _{L, N, M} is M. It corresponds to the tone signal TS _{k of any one of the} tone signals TS 1 to TS _M , and corresponds to any one of the 8th processes of N times. be. Thus, the eighth process N times, it is possible to occupy different magnification according to the individual amplitude A _k to the 8 per treatment.

Further, the waveform data generation unit 2c executes the convergence operation L times, and each of the magnification values γ _1,1,1 to γ _{L, N, M} of L × N × M converges L times. It corresponds to any one of the operations, the convergence operation. Thus, for L times convergence calculation can be made different magnification according to the individual amplitude A _k for each convergence calculation.

It should be noted that, within the scope of the disclosure of the present application, it is possible to freely combine each embodiment, modify any component of each embodiment, or omit any component in each embodiment. ..

The multitone signal generation device and the multitone signal generation method according to the present disclosure can be used, for example, for measuring frequency characteristics at the RF front end of a wireless communication device.

1 Initial value calculation unit, 2, 2a, 2b, 2c Waveform data generation unit, 3 Multitone signal output unit, 11 1st processing unit, 12 2nd processing unit, 13 3rd processing unit, 14 4th processing unit, 15 , 15a 5th processing unit, 16 6th processing unit, 17 7th processing unit, 18 8th processing unit, 21 processor, 22 memory, 23 digital-to-analog conversion circuit (DAC), 24 processing circuit, 100, 100a, 100b , 100c Multitone signal generator.

Claims (17)

1. An initial value calculation unit that calculates the initial value used for the convergence calculation to reduce the PAPR of the multitone signal,
   A waveform data generation unit that generates waveform data indicating the waveform of the multitone signal in which the PAPR is reduced by executing the convergence operation using the initial value.
   A multi-tone signal output unit that outputs the multi-tone signal corresponding to the waveform data generated by the waveform data generation unit is provided.
   _{The initial value includes a plurality of initial phases θ k} corresponding to the plurality of tone signals included in the multitone signal.
   The initial value calculation unit calculates each of the _{plurality of initial phases θ k} by executing algebraic calculation using a predetermined mathematical formula.
   The mathematical expression includes an algebra corresponding to the tone number M of the multitone signal, and includes an algebra corresponding to an integer r that is relatively prime to the tone number M. ..
2. The _{equation, θ k = (2π / M} ) * {(k-1) 2/2} * multitone signal generator according to claim 1, characterized in that the r.
3. The multitone signal generation device according to claim 1, wherein the mathematical formula is θ _k = (2π / M) * {k (k-1) / 2} * r.
4. The convergence operation repeatedly executes a plurality of processes.
   The multitone signal generation device according to any one of claims 1 to 3, wherein the plurality of _{processes include a process of updating each of the plurality of initial phases θ k.}
5. The convergence operation executes the first process, the second process, the third process, the fourth process, and the fifth process a plurality of times.
   The first process includes a process of setting the multitone signal in the frequency domain using the plurality of initial phases θ _k.
   The second process includes a process of converting the multitone signal in the frequency domain into the multitone signal in the time domain.
   The third process includes a process of calculating an error signal in the time domain by calculating a difference value between the value of the multitone signal in the time domain and a predetermined reference value.
   The fourth process includes a process of converting the error signal in the time domain into the error signal in the frequency domain.
   The fifth process includes a process of updating each of the _{plurality of initial phases θ k} based on the difference value between the phase component of the multitone signal in the frequency domain and the phase component of the error signal in the frequency domain. The multitone signal generation device according to any one of claims 1 to 3, wherein the multitone signal generation device is characterized.
6. When the number of tones M is an odd number, the integer r is an even number, and the integer r is an even number.
   The multitone signal generator according to any one of claims 1 to 3, wherein when the number of tones M is an even number, the integer r is an odd number.
7. The convergence operation repeatedly executes a plurality of processes.
   The plurality of processes include a process of generating a pseudo-random number.
   Any one of claims 1 to 3, wherein the plurality of processes include a process of updating each of the _{plurality of initial phases θ k} by different update methods according to the pseudo-random number. The multitone signal generator according to claim 1.
8. The convergence operation executes the first process, the second process, the third process, the fourth process, the sixth process, the fifth process, or the seventh process a plurality of times.
   The first process includes a process of setting the multitone signal in the frequency domain using the plurality of initial phases θ _k.
   The second process includes a process of converting the multitone signal in the frequency domain into the multitone signal in the time domain.
   The third process includes a process of calculating an error signal in the time domain by calculating a difference value between the value of the multitone signal in the time domain and a predetermined reference value.
   The fourth process includes a process of converting the error signal in the time domain into the error signal in the frequency domain.
   The sixth process includes a process of generating a pseudo-random number and a process of comparing the pseudo-random number with a predetermined threshold value.
   When the pseudo-random number is less than the threshold value, the fifth process is performed on the basis of the difference value between the phase component of the multitone signal in the frequency domain and the phase component of the error signal in the frequency domain. Including the process of updating each of the initial phases θ _{k of}
   In the seventh process, when the pseudo-random number is a value equal to or higher than the threshold value, the difference between the phase component of the multitone signal in the frequency domain and the value obtained by multiplying the phase component of the error signal in the frequency domain by a constant. The multitone signal generation device according to any one of claims 1 to 3, further comprising a process of updating each of the plurality of initial phases θ _{k based on a value.}
9. The convergence operation repeatedly executes a plurality of processes.
   The plurality of processes include a process of updating each of the plurality of amplitudes with respect to the plurality of amplitudes corresponding to the plurality of tone signals.
   The multitone signal generation device according to any one of claims 1 to 3, wherein the plurality of _{processes include a process of updating each of the plurality of initial phases θ k.}
10. The convergence operation executes the first process, the eighth process, the second process, the third process, the fourth process, and the fifth process a plurality of times.
    The first process includes a process of setting the multitone signal in the frequency domain using a plurality of amplitudes corresponding to the plurality of tone signals and the plurality of initial phases θ _k.
    The eighth process includes a process of updating each of the plurality of amplitudes using the corresponding magnification value among the plurality of magnification values.
    The second process includes a process of converting the multitone signal in the frequency domain into the multitone signal in the time domain.
    The third process includes a process of calculating an error signal in the time domain by calculating a difference value between the value of the multitone signal in the time domain and a predetermined reference value.
    The fourth process includes a process of converting the error signal in the time domain into the error signal in the frequency domain.
    The fifth process includes a process of updating each of the _{plurality of initial phases θ k} based on the difference value between the phase component of the multitone signal in the frequency domain and the phase component of the error signal in the frequency domain. The multitone signal generation device according to any one of claims 1 to 3, wherein the multitone signal generation device is characterized.
11. Each of the plurality of magnification values corresponds to any one of the plurality of tone signals, and any one of the plurality of times of the eighth process. The multitone signal generation device according to claim 10, wherein the multitone signal generation device corresponds to the eighth process.
12. The waveform data generation unit executes the convergence operation a plurality of times.
    The multitone signal generation device according to claim 11, wherein each of the plurality of magnification values corresponds to one of the plurality of convergence operations.
13. The convergence operation repeatedly executes a plurality of processes.
    The plurality of processes include a process of updating each of the plurality of amplitudes with respect to the plurality of amplitudes corresponding to the plurality of tone signals.
    The plurality of processes include a process of generating a pseudo-random number.
    Any one of claims 1 to 3, wherein the plurality of processes include a process of updating each of the _{plurality of initial phases θ k} by different update methods according to the pseudo-random number. The multitone signal generator according to claim 1.
14. The convergence operation executes the first process, the eighth process, the second process, the third process, the fourth process, the sixth process, the fifth process, or the seventh process a plurality of times.
    The first process includes a process of setting the multitone signal in the frequency domain using a plurality of amplitudes corresponding to the plurality of tone signals and the plurality of initial phases θ _k.
    The eighth process includes a process of updating each of the plurality of amplitudes using the corresponding magnification value among the plurality of magnification values.
    The second process includes a process of converting the multitone signal in the frequency domain into the multitone signal in the time domain.
    The third process includes a process of calculating an error signal in the time domain by calculating a difference value between the value of the multitone signal in the time domain and a predetermined reference value.
    The fourth process includes a process of converting the error signal in the time domain into the error signal in the frequency domain.
    The sixth process includes a process of generating a pseudo-random number and a process of comparing the pseudo-random number with a predetermined threshold value.
    When the pseudo-random number is less than the threshold value, the fifth process is performed on the basis of the difference value between the phase component of the multitone signal in the frequency domain and the phase component of the error signal in the frequency domain. Including the process of updating each of the initial phases θ _{k of}
    In the seventh process, when the pseudo-random number is a value equal to or higher than the threshold value, the difference between the phase component of the multitone signal in the frequency domain and the value obtained by multiplying the phase component of the error signal in the frequency domain by a constant. The multitone signal generation device according to any one of claims 1 to 3, further comprising a process of updating each of the plurality of initial phases θ _{k based on a value.}
15. Each of the plurality of magnification values corresponds to any one of the plurality of tone signals, and any one of the plurality of times of the eighth process. The multitone signal generation device according to claim 14, wherein the multi-tone signal generation device corresponds to the eighth process.
16. The waveform data generation unit executes the convergence operation a plurality of times.
    The multitone signal generation device according to claim 15, wherein each of the plurality of magnification values corresponds to one of the plurality of convergence operations.
17. The step in which the initial value calculation unit calculates the initial value used in the convergence calculation for reducing the PAPR of the multitone signal, and
    A step in which the waveform data generation unit generates waveform data indicating the waveform of the multitone signal in which the PAPR is reduced by executing the convergence operation using the initial value.
    The multitone signal output unit comprises a step of outputting the multitone signal corresponding to the waveform data generated by the waveform data generation unit.
    _{The initial value includes a plurality of initial phases θ k} corresponding to the plurality of tone signals included in the multitone signal.
    The initial value calculation unit calculates each of the _{plurality of initial phases θ k} by executing algebraic calculation using a predetermined mathematical formula.
    The mathematical expression includes an algebra corresponding to the tone number M of the multitone signal, and includes an algebra corresponding to an integer r that is relatively prime to the tone number M. ..

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