JP2011040956A - Radio transmitter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio transmitter for maintaining both high efficiency and distortion suppression. <P>SOLUTION: Amplitude component and phase component of an input high-frequency signal are extracted. Meanwhile, a distributor 8 distributes a carrier signal generated by an oscillator 7 into a plurality of parts, to generate a plurality of signals of a single frequency. The signals are respectively separately subjected to phase shifting, to be input to power amplifiers 101 to 10m so that the signals are amplified separately. Each amplified signal is input to a switch 11, and signals having the phase of a phase component of the high-frequency signal are switched and output. Biases reflecting the amplitude component of the high-frequency signal are respectively set in the respective power amplifiers 101 to 10m. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to, for example, an orthogonal frequency division multiplexing (OFDM) wireless transmission apparatus.

In a wireless communication facility, a large amount of power is consumed in a high-frequency power amplifier provided in a wireless transmission device. In order to improve power efficiency and reduce power consumption, a technique called EER (Envelope Elimination and Restoration) is used. (For example, refer to Patent Document 1).
In a radio transmission apparatus to which EER is applied, a transmission signal is processed by being separated into an amplitude signal and a phase signal. Since the phase signal is a phase-modulated signal, the bandwidth is widened, the bandwidth required for each amplifier up to the high-frequency power amplifier at the final stage is widened, and it is necessary to use a high-cost broadband amplifier. If the available band does not reach the required value, distortion will occur in the output signal of the final high-frequency power amplifier, which becomes a problem.

  In Patent Document 1, output distortion is minimized by limiting the band under certain conditions. However, in this method, it is necessary to mount a low-pass filter on both the amplitude signal and the phase signal, and it is also necessary to change the filter constant according to the modulation signal bandwidth. Therefore, in the mobile phone system in which the modulation signal band changes, it is necessary to change the filter constant, and a circuit for responding to the change is required, and the control is complicated.

JP 2004-320735 A

As described above, in the wireless transmission device to which the existing EER is applied, in order to separate and handle the amplitude component and the phase component, it is necessary to widen the phase processing part, and both the circuit configuration and the control system are complicated. . The provision of technology that can solve this problem is awaited.
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a radio transmission apparatus that achieves both high efficiency maintenance and distortion suppression.

  In order to achieve the above object, according to one aspect of the present invention, in a radio transmission apparatus that generates an output signal by amplifying a high-frequency input signal with a specified amplification degree, the amplitude component and the phase component of the input signal are individually set. A signal processing unit that extracts the carrier signal, a plurality of phase shift units that shift the carrier signal from the oscillator by individual phase shift amounts, and each of these phase shift units. A plurality of power amplifying units for amplifying the output of the phase shift unit; a switch for switching and outputting one of the outputs of the plurality of power amplifying units in a time-sharing manner; and the plurality of power amplifying units based on the amplitude component A gain control unit that individually controls the gain of the output signal, and a switching control unit that switches the switch based on the phase component, and the gain control unit outputs the output of the phase shift unit to the amplification degree. A wireless transmission device, wherein the switch is switched to selectively output an output having a phase corresponding to the phase component of the output of the power amplification unit. Provided.

  By taking such means, the amplitude and phase of the input signal are individually extracted. On the other hand, a carrier wave signal is generated locally by an oscillator, branched into a plurality of systems, and individually given a phase shift. The signals of these systems are each amplified and applied to the switch, and a signal having a phase corresponding to the input signal is switched and output in a time division manner. Thereby, in the output signal, a phase modulation signal reflecting the phase of the input signal is obtained.

  According to the present invention, it is possible to provide a wireless transmission device that achieves both high efficiency maintenance and distortion suppression.

The functional block diagram which shows an example of the radio | wireless transmitter which applied EER. 1 is a functional block diagram showing a first embodiment of a wireless transmission device according to the present invention. The functional block diagram which shows 2nd Embodiment of the wireless transmitter concerning this invention. The figure which shows an example of the phase shift parts 91-9m. The functional block diagram which shows 3rd Embodiment of the wireless transmission device concerning this invention. The functional block diagram which shows 4th Embodiment of the radio | wireless transmitter concerning this invention. The functional block diagram which shows 5th Embodiment of the radio | wireless transmitter concerning this invention. The functional block diagram which shows 6th Embodiment of the radio | wireless transmission apparatus concerning this invention. The functional block diagram which shows 7th Embodiment of the radio | wireless transmitter concerning this invention. The functional block diagram which shows 8th Embodiment of the radio | wireless transmitter concerning this invention. The functional block diagram which shows 9th Embodiment of the radio | wireless transmitter concerning this invention. The functional block diagram which shows 10th Embodiment of the radio | wireless transmitter concerning this invention. The functional block diagram which shows 11th Embodiment of the radio | wireless transmitter concerning this invention. The functional block diagram which shows 12th Embodiment of the radio | wireless transmitter concerning this invention. The functional block diagram which shows 13th Embodiment of the radio | wireless transmitter concerning this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, EER will be further described with reference to FIG. FIG. 1 is a functional block diagram illustrating an example of a wireless transmission device to which EER is applied. In FIG. 1, a high-frequency signal given from a signal input terminal 31 is separated into two systems in a hybrid circuit 32, and one of them extracts an amplitude component by an amplitude detector 33 and gives it to a bias controller 37. On the other hand, only the phase component is extracted by the limiter 34, phase-shifted by the delay unit 35, and then applied to the nonlinear high-frequency power amplifier 36. The bias voltage (power supply voltage) of the high frequency power amplifier 36 is controlled by the amplitude component of the input signal extracted by the amplitude detector 33. As a result, the amplitude and phase of the transmission signal are reconstructed, and the high-frequency signal can be amplified with high efficiency. However, since the transmission signal is separated into an amplitude signal and a phase signal, it is necessary to widen the limiter 34, the delay unit 35, and the high-frequency power amplifier 36 that process the phase signal, resulting in an increase in cost. Hereinafter, an embodiment capable of solving such an adverse effect will be disclosed.

[First Embodiment]
FIG. 2 is a functional block diagram showing the first embodiment of the wireless transmission apparatus according to the present invention. In FIG. 2, a carrier wave signal is generated by an oscillator 7. This carrier wave signal is distributed to a plurality of systems (here, m systems) by distributor 8, and individually phase-shifted by phase shift units 91 to 9m, and then power amplified by power amplifiers 101 to 10m. In this embodiment, a phase shift amount that is an integral multiple of a value obtained by dividing 360 ° by m is individually set for each of the phase shift units 91 to 9m. For example, if m = 6, phase shift amounts of 60 °, 120 °, 180 °, 240 °, 300 °, and 360 ° are set for each of the phase shift units 91 to 96.

  On the other hand, the high-frequency signal given from the signal input terminal 1 is given to the signal processing unit 2, and the amplitude component is extracted by the internal amplitude signal generation unit 3 and the phase component is extracted by the phase signal generation unit 4. Among these components, the amplitude component is given to the power amplifier control unit 12 via the delay adjustment unit 5. The power amplifier control unit 12 individually controls the bias in the power amplifiers 101 to 10m based on the extracted amplitude component.

  The outputs of the power amplifiers 101 to 10m are signals having a single frequency based on a carrier wave signal and differing only in phase. These output signals are input to the switch (SW) 11, and one of them is selectively extracted and output from the high-frequency signal output terminal 14. The switch 11 is subjected to switching control by the switching control unit 13 that has received the switching control signal from the switching signal generation unit 6. The switching control signal is generated based on the phase component extracted by the phase signal generation unit 4. That is, the switch 11 is switch-controlled so that a single frequency signal having the same phase as the extracted phase component is output.

  On the other hand, the bias of the power amplifiers 101 to 10m is controlled according to the amplitude signal extracted by the signal processing unit 2 by the power amplifier control unit 12, and the output amplitude of the power amplifiers 101 to 10m changes. As a result, a signal reflecting both the phase component and the amplitude component of the high-frequency signal applied from the signal input terminal 1 is reproduced and output from the high-frequency signal output terminal 14.

  Further, the carrier wave signal distributed by the distributor 8 is input to the signal processing unit 2, and the phase of this reference signal is used as a reference phase for matching the timing for reproducing the amplitude and the phase. The delay amount in the delay adjustment unit 5 is adjusted based on this reference signal, and the power amplifier control unit 12 determines the timing of amplitude change. The switching signal generator 6 also determines the phase signal selection switching timing based on the phase of the reference signal.

In the above configuration, the phase-modulated signal is generated only in the subsequent stage of the switch 11, and the signal from the switch 11 is output without passing through a device that limits the band. Accordingly, it is possible to obtain a high frequency signal output without distortion deterioration.
Furthermore, since a single carrier frequency is input to the power amplifiers 101 to 10m, the bandwidth requirement is minimized. Therefore, signal degradation with respect to the band, that is, occurrence of distortion degradation can be minimized. Moreover, since the demand for the bandwidth of the power amplifiers 101 to 10m is greatly relaxed, the efficiency of each of the power amplifiers 101 to 10m can be increased. The decrease in efficiency is generally caused by an increase in bandwidth. Conversely, if the bandwidth can be minimized, the efficiency can be increased accordingly.

  Increasing the bandwidth of the input / output matching circuit as in the existing technology deviates from the efficient matching condition. However, according to the configuration of FIG. 2, the input has a matching condition for a single frequency. It is only necessary to satisfy this condition, and the output only needs to satisfy the matching condition for the band increase due to the intensity modulation signal. Therefore, it is possible to set a matching condition that places importance on efficiency.

  Note that all of the power amplifiers 101 to 10m may be operated in the same manner, or only a power amplifier having a necessary phase component may be operated. Such control is executed under the control of the power amplifier control unit 12. If only a power amplifier having a necessary phase component is operated, an efficient wireless transmission device can be realized.

  As described above, in this embodiment, the amplitude component and phase component of the input high-frequency signal are extracted. On the other hand, the carrier wave signal generated by the oscillator 7 is distributed into a plurality by the distributor 8 to generate a plurality of single frequency signals. These signals are individually phase-shifted and input to the power amplifiers 101 to 10m to be individually amplified. Each amplified signal is input to the switch 11, and a signal having the phase of the phase component of the high-frequency signal is switched and output. Each of the power amplifiers 101 to 10m is set with a bias reflecting the amplitude component of the high frequency signal. Since it did in this way, the restriction | limiting of the zone | band with respect to each device can be suppressed to the minimum, and it becomes possible to implement | achieve a highly efficient and broadband radio | wireless transmitter.

[Second Embodiment]
FIG. 3 is a functional block diagram showing a second embodiment of the wireless transmission apparatus according to the present invention. 3, parts that are the same as those in FIG. 2 are given the same reference numerals, and only different parts will be described here. The wireless transmission device of FIG. 3 is obtained by replacing the power amplifiers 101 to 10m of FIG. 2 with power amplification units A1 to Am. The power amplifiers A1 to Am distribute the output of the phase shift unit into a plurality of parts by the distributor 15, and amplify them by the plurality of power amplifiers 101 to 10n and combine the signals by the multiplexer 16 to the switch 11. . With such a configuration, each of the power amplifiers 101 to 10n can be replaced with one having a smaller and smaller output than the power amplifiers 101 to 10m of FIG.

  In the above configuration, each of the power amplifiers 101 to 10n is driven only by a power amplifier necessary for determining the amplitude by the power amplifier control unit 12. That is, the number of operating power amplifiers is determined according to the desired amplitude, the number of operating power amplifiers can be kept to a minimum, power consumption of unnecessary power amplifiers can be reduced, and efficiency can be increased.

  Furthermore, with the above configuration, both the amplitude and phase can be controlled with discrete values. That is, since the amplitude can be controlled by discretely switching the number of driving of the power amplifiers 101 to 10n for each phase, a configuration suitable for IC (Integrated Circuit) can be realized. As described above, according to this embodiment, all analog signals of the main signal system to be amplified can be handled at a single frequency, and all control signals can be realized by control with digital signals. Therefore, high integration of devices can be promoted. In addition, the signal processing unit 2 is more suitably configured by digital processing. In such a case, an analog / digital converter or a digital / analog converter may be provided at the interface with the analog signal.

  FIG. 4 is a diagram illustrating an example of the phase shift units 91 to 9m. The phase shifters 91 to 9m give a fixed phase shift to the carrier wave signal distributed by the distributor 8, and the function can be realized by wiring members having different wiring lengths, for example. As shown in FIG. 4, it is possible to bend the shape of the wiring pattern of the substrate and change the phase with respect to the output from the difference between the inner pattern length and the outer pattern length.

[Third Embodiment]
FIG. 5 is a functional block diagram showing a third embodiment of the wireless transmission apparatus according to the present invention. 3, parts that are the same as those in FIG. 2 are given the same reference numerals, and only different parts will be described here. The wireless transmission device of FIG. 5 includes PLL circuits 181 to 18m instead of the phase shift units 91 to 9m of FIG. By controlling the reference voltage for the phase comparison value provided in the PLL (Phase Lock Loop) circuit, the output phase can be set to an arbitrary phase. As a result, finer phase control can be realized.

[Fourth Embodiment]
FIG. 6 is a functional block diagram showing a fourth embodiment of the wireless transmission apparatus according to the present invention. In FIG. 6, parts common to FIG. 5 are given the same reference numerals, and only different parts will be described here. In the wireless transmission device of FIG. 6, a part of the output signal is branched by a distributor 19 provided on the output side of the switch 11 and input to the phase control unit 20. The phase control unit 20 detects the phase of the output signal and compares the switching control signal from the switching signal generation unit 6 to determine the path of the phase signal to be controlled. Based on the result, the phase control unit 20 performs control to adjust the output phase of the PLL circuit to be controlled to a predetermined phase.

  In FIG. 6, when the output phases of the power amplifiers 101 to 10m are combined in the switch 11, if the data path of the signal from the PLL circuit to the switch 11 is different, a signal having the intended phase cannot be obtained, and as a result, the output signal The waveform deteriorates. Such a delay difference occurs when the delay time of a signal differs due to a delay error due to the arrangement of each circuit or a change in conditions such as environmental temperature and power supply voltage. According to this embodiment, it becomes possible to correct such a phase delay difference, and further suppress the deterioration of the signal waveform.

[Fifth Embodiment]
FIG. 7 is a functional block diagram showing a fifth embodiment of the wireless transmission apparatus according to the present invention. In FIG. 7, parts that are the same as those in FIG. 6 are given the same reference numerals, and only different parts will be described here. The wireless transmission device of FIG. 7 is obtained by replacing the power amplifiers 101 to 10m of FIG. 6 with power amplification units A1 to Am. With such a configuration, the output amplitude can be controlled by controlling the number of operations of the power amplifier as in the second embodiment, and the control can be simplified and the efficiency can be further increased.

[Sixth Embodiment]
FIG. 8 is a functional block diagram showing a sixth embodiment of the wireless transmission apparatus according to the present invention. In FIG. 8, parts that are the same as those in FIG. 5 are given the same reference numerals, and only different parts will be described here. In the wireless transmission device of FIG. 8, a part of the output signal is branched by a distributor 19 provided on the output side of the switch 11 and input to the gain control unit 21. The gain control unit 21 detects the level of the output signal and passes the result to the power amplifier control unit 12. The power amplifier control unit 12 compensates the gain deviation of the target power amplifier based on the level of the output signal. There is a method of multiplying the signal amplitude by the deviation for compensation of the gain deviation, which can be easily realized.

  When variations in loss occur for each signal path, an amplitude error occurs in the output of the switch 11, which also causes signal degradation. Therefore, in this embodiment, a distributor 19 is provided at the output of the switch 11, and the distributed output is input to the gain control unit 21 to compensate for the gain deviation of the outputs of the power amplifiers 101 to 10m. By doing so, it is also possible to prevent distortion of the output signal waveform.

[Seventh Embodiment]
FIG. 9 is a functional block diagram showing a seventh embodiment of the wireless transmission apparatus according to the present invention. In FIG. 9, parts that are the same as those in FIG. 8 are given the same reference numerals, and only different parts will be described here. The wireless transmission device of FIG. 9 is obtained by replacing the power amplifiers 101 to 10m of FIG. 8 with power amplification units A1 to Am. With such a configuration, the output amplitude can be controlled by controlling the number of operations of the power amplifier as in the fifth embodiment, so that the control can be simplified and the efficiency can be further increased.

[Eighth Embodiment]
FIG. 10 is a functional block diagram showing an eighth embodiment of the wireless transmission apparatus according to the present invention. 10 includes the phase control unit 20 in FIG. 8 and the gain control unit 21 in FIG. 9, and a part of the output signal branched by the distributor 19 is supplied to both the phase control unit 20 and the gain control unit 21. It comes to input. That is, the phase value of the output signal is detected by the phase controller 20, and the amplitude value of the output signal is detected by the gain controller 21. Then, based on the result, the PLL circuits 181 to 18m are controlled so as to realize predetermined phase values and amplitude values, respectively, and a correction value is passed to the power amplifier control unit 12. With the above configuration, both the phase and the amplitude can be corrected, and deterioration of the output high-frequency signal due to the phase shift due to the delay time difference or the amplitude shift due to the loss difference can be suppressed.

[Ninth Embodiment]
FIG. 11 is a functional block diagram showing a ninth embodiment of a wireless transmission apparatus according to the present invention. In FIG. 11, parts common to FIG. 10 are denoted by the same reference numerals, and only different parts will be described here. The wireless transmission device of FIG. 11 is obtained by replacing the power amplifiers 101 to 10m of FIG. 10 with power amplification units A1 to Am. With such a configuration, the output amplitude can be controlled by controlling the number of operations of the power amplifier as in the fifth embodiment, so that the control can be simplified and the efficiency can be further increased.

[Tenth embodiment]
FIG. 12 is a functional block diagram showing a tenth embodiment of the wireless transmission apparatus according to the present invention. In FIG. 12, parts that are the same as those in FIG. 2 are given the same reference numerals, and only different parts will be described here. The wireless transmission device of FIG. 12 is obtained by replacing the phase shift units 91 to 9m of FIG. 2 with phase signal generation units 221 to 22m and digital / analog converters 231 to 23m. The phase signal generation units 221 to 22m generate and output m signals having different phases based on the carrier frequency from the oscillator 7, respectively. The output is converted into an analog waveform by the digital / analog converters 231 to 23m and then input to the power amplifiers 101 to 10m. If carrier waves having different phases are digitally generated in this way, a configuration that is more suitable for IC implementation can be achieved.

[Eleventh embodiment]
FIG. 13 is a functional block diagram showing an eleventh embodiment of the radio transmitting apparatus according to the present invention. In FIG. 13, parts common to FIG. 12 are denoted by the same reference numerals, and only different parts will be described here. The wireless transmission device of FIG. 13 is obtained by replacing the power amplifiers 101 to 10m of FIG. 12 with power amplification units A1 to Am. With such a configuration, the output amplitude can be controlled by controlling the number of operations of the power amplifier as in the second embodiment, and the control can be simplified and the efficiency can be further increased.

[Twelfth embodiment]
FIG. 14 is a functional block diagram showing a twelfth embodiment of the wireless transmission apparatus according to the present invention. 14, parts that are the same as those in FIG. 13 are given the same reference numerals, and only different parts will be described here. In FIG. 14, the outputs of the phase signal generators 221 to 22m in FIG. 13 are first input to the distortion compensators (phase distortion compensators) 241 to 24m. The output is converted into an analog waveform by the digital / analog converters 231 to 23m and then input to the power amplifiers 101 to 10m. Thereafter, the high-frequency signal output through the switch 11 is branched by the distributor 19, digitally converted by the analog / digital converter 27, and given to the distortion compensation correction calculation unit 26.

  The distortion compensation correction calculation unit 26 compares the input signal and the output signal, and extracts the degree of signal degradation. Then, the signal degradation component is divided into a phase component and an amplitude component, and each correction value is calculated. This is used as a distortion compensation unit 241 to 24m that compensates for phase distortion, and a distortion compensation unit that compensates for amplitude distortion (amplitude distortion compensation). Part) 25 to compensate each distortion. By doing so, it is possible to output a high-frequency signal with little signal degradation even if a power amplifier with a small bandwidth is used.

  In the above configuration, the output signal is taken out by the distributor 19, and the amplitude value and the phase value are detected and fed back, so that the phase distortion and the amplitude distortion are individually eliminated to suppress the output signal deterioration. . Even in this way, it is possible to realize a high-efficiency and wide-band wireless transmission device.

[Thirteenth embodiment]
FIG. 15 is a functional block diagram showing a thirteenth embodiment of the wireless transmission apparatus according to the present invention. In FIG. 15, parts that are the same as those in FIG. 14 are given the same reference numerals, and only different parts will be described here. The wireless transmission device of FIG. 15 is obtained by replacing the power amplifiers 101 to 10m of FIG. 14 with power amplification units A1 to Am. With such a configuration, the output amplitude can be controlled by controlling the number of operations of the power amplifier as in the second embodiment, and the control can be simplified and the efficiency can be further increased.

  In addition, this invention is not limited to the said embodiment, In an implementation stage, a component can be deform | transformed and embodied in the range which does not deviate from the summary. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

  DESCRIPTION OF SYMBOLS 1 ... Signal input terminal, 2 ... Signal processing part, 3 ... Amplitude signal generation part, 4 ... Phase signal generation part, 5 ... Delay adjustment part, 6 ... Switching signal generation part, 7 ... Oscillator, 8 ... Distributor, 91- DESCRIPTION OF SYMBOLS 9m ... Phase shift part, 101-10m ... Power amplifier, 11 ... Switch (SW), 12 ... Power amplifier control part, 13 ... Switching control part, 14 ... High frequency signal output terminal, A1-Am ... Power amplification part, 15 ... Distributor, 16 ... multiplexer, 181 to 18m ... PLL circuit, 19 ... distributor, A1 to Am ... power amplifier, 20 ... phase controller, 21 ... gain controller, 221-22m ... phase signal generator, 231 to 23m: Digital / analog converter, 241 to 24m: Distortion compensation unit, 25: Distortion compensation unit, 26: Distortion compensation correction calculation unit, 27 ... Analog / digital converter,

Claims (8)

In a wireless transmission device that generates an output signal by amplifying a high-frequency input signal with a specified amplification factor,
A signal processing unit for individually extracting the amplitude component and the phase component of the input signal;
An oscillator for generating a carrier wave signal;
A plurality of phase shift units for shifting the carrier signal from the oscillator by individual phase shift amounts;
A plurality of power amplifying units that are provided for each of these phase shift units and amplify the output of each phase shift unit,
A switch that switches and outputs one of the outputs of the plurality of power amplifiers in a time-sharing manner;
A gain control unit for individually controlling the gains of the plurality of power amplification units based on the amplitude component;
A switching control unit that switches the switch based on the phase component;
The gain control unit amplifies the output of the phase shift unit with a gain corresponding to the amplification degree,
The wireless transmission apparatus, wherein the switching control unit switches the switch so as to selectively output an output having a phase corresponding to the phase component among outputs of a power amplification unit. Each of the plurality of power amplification units is
A distributor that distributes the output of the input phase shift unit to a plurality of;
A plurality of power amplifiers for individually amplifying the distributed signals;
A multiplexer for multiplexing the outputs of the plurality of power amplifiers,
The gain controller is
The radio transmission apparatus according to claim 1, wherein a bias of the power amplifier is controlled based on the amplitude component, and an operation of the power amplifier is driven or stopped based on the amplitude component. The wireless transmission device according to claim 1, wherein the plurality of phase shift units are wiring members having different line lengths. The wireless transmission device according to claim 1, wherein the plurality of phase shift units are PLL (Phase Lock Loop) circuits. Furthermore, a distribution means for distributing and outputting a part of the output of the switch;
A phase control unit that controls a phase value of the phase shift unit based on the distribution output and the phase component;
The radio transmission apparatus according to claim 1, wherein the phase control unit maintains a phase value of the distribution output at a constant value. Furthermore, it comprises a distribution means for distributing and outputting a part of the output of the switch,
The radio transmission apparatus according to claim 1, wherein the gain control unit maintains a gain of the output signal at a specified value based on the distributed output. The phase shift unit includes:
A phase signal generator for digitally generating a phase signal;
The radio transmission apparatus according to claim 1, further comprising a digital / analog converter that converts the phase signal generated by the phase signal generation unit into an analog signal. Furthermore, a distribution means for distributing and outputting a part of the output of the switch;
An analog / digital converter for converting the distributed output into a digital signal;
A distortion compensation calculation unit for calculating a control value for compensating for distortion of the output signal from the output of the analog / digital converter;
A phase distortion compensator for correcting the phase signal based on the control value;
The radio transmission apparatus according to claim 7, further comprising an amplitude distortion compensation unit that performs distortion compensation on the amplitude component based on the control value.

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