JP2002228694A - Strain phase measuring apparatus, down converter, low strain power amplifier, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately measure the phase shift quantity of a strain component with a strain phase measuring apparatus in the case where the sizes of strain components are different from each other. SOLUTION: The strain measuring apparatus is provided with a frequency range conversion means 105 for converting digital signals having a strain component by using Fourier transform, and a phase calculation means 106 for calculating the phase shift of the strain component based on the result of the transform with the frequency range conversion means 105.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a distortion phase measuring apparatus, a down converter, a low distortion power amplifier, and a program for measuring a phase shift amount of a distortion component of a signal generated from a power amplifier, for example.

[0002]

2. Description of the Related Art First, in order to explain the phase of distortion (ie, the amount of phase shift of a distortion component), an output voltage V when two waves having different frequencies are input to a power amplifier is expressed by the following equation.

[0003]

V (t) = A (cos [ω ₁ t] + cos [ω ₂
t]) + BLcos [(2ω ₁ −ω ₂ ) t + φ _3L ] + BU
_{cos [(2ω 2 -ω 1)} t + φ 3U] Here, omega _1, omega ₂ is the angular frequency of the input signal, A is the amplitude component of the voltage of ₁ the angular frequency of the output voltage omega, an omega ₂ signal, BL and BU are amplitude components of the voltage of the third-order intermodulation distortion generated on the low frequency side and the high frequency side, respectively. Φ _3L and φ _3U are phase components of third-order intermodulation distortion generated on the low frequency side and the high frequency side, respectively, that is, the amount of phase shift of the distortion component.

Next, the configuration of a conventional distortion phase measuring device will be described with reference to FIG. 7, which is a configuration diagram of a conventional distortion phase measuring device. This distortion phase measuring device is a device for inspecting in advance characteristics related to distortion of the power amplifier 704 used in various systems for performing power amplification.

A CW (Continuous) signal having a different signal frequency input from an input terminal 701 as an input signal.
The two waves (Wave, continuous wave) are distributed to two paths by a distribution circuit 703.

One of them is input to a delay circuit 706. The other is input to a power amplifier 704 for measuring the phase of the distortion, and the output is input to a vector adjustment circuit 705 for adjusting the magnitude and phase of the signal. The output from the vector adjustment circuit 705 is
The output of the delay circuit 706 and the synthesis circuit 707 are synthesized.

Initially, the input signal is supplied to the power amplifier 70
4 has small enough power to not distort,
The vector adjustment circuit 705 is adjusted so that the frequency component of the input signal is suppressed.

Thereafter, when the input signal is increased, an output signal having the same frequency ω ₁ and ω ₂ as the two input signals described above and having a phase shift appears from the output terminal 702 due to the nonlinearity of the power amplifier 704. Come. Therefore, by measuring the passing phases of these output signals, the amount of phase shift of the distortion component has been measured.

[0009]

However, such a conventional distortion phase measuring method using the distortion phase measuring apparatus uses two distortions IM3LO and IM3UP (a low-frequency component of the third-order intermodulation distortion is IM3LO, and a frequency of the third-order intermodulation distortion is IM3LO). It is effective when the magnitude of the higher component is called IM3UP), that is, when the above-mentioned amplitude components BL and BU are equal,
If they are different, it is difficult to apply.

The present invention has been made in consideration of the above-described conventional problems, and for example, a distortion phase measuring apparatus capable of accurately measuring a phase shift amount of a distortion component even when the magnitudes of the distortion components are different from each other. It is an object to provide a down converter, a low distortion power amplifier, and a program.

[0011]

Means for Solving the Problems The first invention (claim 1)
A) a conversion unit for performing a conversion using a Fourier transform on a digital signal having a distortion component, and calculating a phase shift amount of the distortion component based on a result of the conversion by the conversion unit. This is a distortion phase measurement device provided with calculation means for performing the calculation.

According to a second aspect of the present invention (corresponding to claim 2), in the digital signal having the distortion component, a time domain waveform of an input signal having a distortion component input from the outside is detected as an analog signal, The analog signal is analog /
It is a distortion phase measuring device of the first invention which is a digital signal obtained by digital conversion.

According to a third aspect of the present invention (corresponding to claim 3), the conversion using a Fourier transform for a digital signal having a distortion component is defined as a Fourier transform for a time-domain waveform analog / digital converted to the digital signal. The distortion phase measuring apparatus according to the second aspect of the present invention, which is a conversion into a frequency domain waveform using the conversion.

According to a fourth aspect of the present invention (corresponding to claim 4), the input signal having a distortion component inputted from the outside has four signal components having equal frequency intervals, and the distortion component is Of the four signal components, the signal component having the lowest frequency and the signal component having the highest frequency. To calculate the phase shift amount of the distortion component means that the four signal components are calculated using the waveform in the frequency domain. Calculate the instantaneous phase of
(1) The amount of phase shift of the lowest frequency signal component is calculated from the sum of the calculated instantaneous phase of the lowest frequency signal component and the calculated instantaneous phase of the second highest frequency signal component. , Calculated as a value obtained by subtracting twice the instantaneous phase of the second lowest signal component of the calculated frequency,
(2) The amount of phase shift of the highest frequency signal component is calculated from the sum of the calculated instantaneous phase of the highest frequency signal component and the calculated instantaneous phase of the second lowest signal component. The third aspect of the present invention is a distortion phase measuring apparatus according to the third aspect of the present invention, which calculates a value obtained by subtracting twice the instantaneous phase of the second highest signal component of the calculated frequency.

According to a fifth aspect of the present invention (corresponding to claim 5), the calculated phase shift of the signal component having the lowest frequency is the instantaneous phase of the signal component having the second lowest frequency. And the instantaneous phase of the calculated lowest frequency signal component and the instantaneous value of the calculated second lowest signal component when the calculated instantaneous phase of the second highest signal component of the frequency are equal. Phase difference, the calculated phase shift amount of the highest frequency signal component is the instantaneous phase of the second lowest signal component of the calculated frequency and the second phase of the calculated frequency. A fourth book which is a difference between the calculated instantaneous phase of the highest frequency signal component and the calculated instantaneous phase of the second highest signal component when the instantaneous phase of the high signal component is equal. Invented distortion phase measurement It is the location.

According to a sixth aspect of the present invention (corresponding to claim 6), in order to generate a digital signal having the distortion component, the frequency of the signal component of the input signal input from the outside is down-converted in advance. It is a distortion phase measuring device of the second invention having a down converter.

A seventh aspect of the present invention (corresponding to claim 7) is provided with training means for performing training for correcting a group delay time difference of a path through which a signal component of the input signal input from the outside passes. It is the sixth distortion phase measuring apparatus of the present invention.

An eighth aspect of the present invention (corresponding to claim 8) is a conversion means for performing a conversion using a Fourier transform on a digital signal having a distortion component, and the distortion component based on a result of the conversion. A digital signal subjected to the conversion in the distortion phase measurement apparatus having a calculation means for calculating the amount of phase shift of the input signal is converted into a time domain waveform of an input signal having a distortion component input from the outside as an analog signal. This is a down-converter that down-converts the frequency of the signal component of the input signal input from the outside in advance in order to detect the analog signal and generate the analog signal by analog-to-digital conversion.

A ninth aspect of the present invention (corresponding to claim 9) is that the first to fourth mixer circuits and the first to fourth band circuits for inputting signals from the first to fourth mixer circuits, respectively. The input signal having a distortion component input from the outside has four signal components having equal frequency intervals, and among the four signal components, (1) the signal component having the lowest frequency is After being down-converted by the first mixer circuit, filtered by the first band-pass filter, and (2) the signal component having the second lowest frequency is down-converted by the second mixer circuit. (3) The signal component having the second highest frequency is down-converted by the third mixer circuit, and then filtered by the third band-pass filter. 4) Signal components higher frequency, after being down-converted by the fourth mixer circuit, an eighth down converter of the present invention which is filtered by the fourth band pass filter.

A tenth aspect of the present invention (corresponding to claim 10) is that the first to fourth bandpass filters and the first to fourth bandpass filters for inputting signals from the first to fourth bandpass filters, respectively. Mixer circuit, and a fifth to an eighth band-pass filter for respectively inputting signals from the first to fourth mixer circuits, the input signal having a distortion component input from the outside, the frequency interval , And among the four signal components, (1) the signal component with the lowest frequency is filtered by the first band-pass filter and then down-converted by the first mixer circuit. The signal is converted and the unnecessary wave is removed by the fifth band-pass filter. (2) The signal component having the second lowest frequency is filtered by the second band-pass filter, and then is filtered by the second mixer circuit. Dow The signal is converted, unnecessary waves are removed by the sixth band-pass filter, and (3) the signal component having the second highest frequency is filtered by the third band-pass filter, and then filtered by the third mixer circuit. The signal is down-converted, unnecessary waves are removed by the seventh band-pass filter, and (4) the signal component having the highest frequency is filtered by the fourth band-pass filter and then down-converted by the fourth mixer circuit. An eighth aspect of the present invention is the downconverter of the present invention, which is converted and unnecessary waves are removed by the eighth bandpass filter.

The eleventh invention (corresponding to claim 11) provides:
It is a low distortion power amplifier using any one of the first to seventh distortion phase measuring devices of the present invention.

The twelfth invention (corresponding to claim 12) provides:
A conversion unit for performing a conversion using a Fourier transform on a digital signal having a distortion component of the distortion phase measurement apparatus according to the first aspect of the present invention, and the distortion component based on a result of the conversion by the conversion unit. This is a program for causing a computer to function as all or a part of the calculation means for calculating the amount of phase shift.

[0023]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) First, the configuration of a distortion phase measuring apparatus according to the present embodiment will be described with reference to FIG. 1, which is a configuration diagram of the distortion phase measuring apparatus according to the first embodiment.

The distortion phase measuring apparatus according to the present embodiment has a time waveform detecting means 103 for detecting a time waveform of a signal.
And an analog-to-digital converter 104 connected to the output of the time waveform detector 103 for converting the detected time waveform from an analog signal to a digital signal, and connected to the output of the analog-to-digital converter 104 to perform Fourier transform. A frequency domain conversion unit 105 for converting a time domain waveform into a frequency domain waveform, and a frequency conversion unit 1
And a phase calculating means 106 for calculating the phase of the distortion.

In the present embodiment, signals input to a power amplifier (not shown) have different frequencies f ₁ , f _1
2 (f ₁ <f ₂ ).

However, since the output signal from the power amplifier becomes a signal including a distortion signal (third-order intermodulation distortion), the signal input to the distortion phase measuring device as the output signal from the power amplifier is f ₁ , 2f ₁ −f ₂ , 2f ₂ −f ₁ other than f ₂
Is a signal having a frequency of That is, the signals input to the input terminal 101 of the distortion phase measuring apparatus of FIG. 1 are four waves having frequencies 2f ₁ -f ₂ , f ₁ , f ₂ , and 2f ₂ -f ₁ and having the same frequency interval. .

Next, the operation of the distortion phase measuring apparatus according to the present embodiment will be described.

The signal input to the input terminal 101 is detected by a time waveform detector 103 and converted to a digital signal by an analog-to-digital converter 104.

The digital signal generated in this manner is a time-domain waveform V (t), which is converted into a frequency-domain waveform by a frequency domain conversion unit 105 using (fast) Fourier transform. Area data Φ (ω, t)
Is generated. Note that Φ (ω, t) is the declination portion of the value (complex value) represented by the waveform in the frequency domain obtained by the above-described Fourier transform, but it is nothing but the angular frequency ω and the instantaneous phase at time t.

Then, the phase calculating means 106 uses the phases at the respective times t of the signals having the frequencies f ₁ , f ₂ , 2f ₁ -f ₂ , and 2f ₂ -f ₁ to calculate the distortion phase ( That is, the phase shift amount of the distortion component) is calculated. That is, the phases φ _3L and φ _3U of the distortion have frequencies f ₁ ,
The phase Φ (ω ₁ , t), Φ (ω ₂ , t), Φ (ω ₁ , t), Φ (ω ₁ , t) at each time of the signal f ₂ , 2f ₁ −f ₂ , 2f ₂ −f ₁ ,
Φ (2ω ₂ −ω ₁ , t) is given by the following equation.

[0032]

## EQU2 ## φ _3L = Φ (ω ₂ , t) −2Φ (ω ₁ , t) + Φ
(2ω ₁ -ω ₂ , t)

[0033]

Equation 3 φ _3U = Φ (ω ₁ , t) −2Φ (ω ₂ , t) + Φ
(2ω ₂ −ω ₁ , t) When the frequency is high, the down-converting means 2
As shown in FIG. 2, which is a configuration diagram of the distortion phase measuring device having the frequency converter 03, a high-precision distortion measurement is possible by disposing the down-converting means 203 for down-converting the frequency before the time waveform detecting means 203. Becomes

Here, specific down-converting means (also referred to as down-converter) include mixers 303 to 306 and band-pass filters 307 to 31.
FIG. 3, which is a configuration diagram of a down-conversion means having 0,
Or bandpass filters 403 to 406, 411 to 4
A configuration as shown in FIG. 4, which is a configuration diagram of a down-converting unit having the mixer 14 and the mixers 407 to 410, can be considered.

Therefore, the band pass filters 403 to 40
The case where the down-converting means (see FIG. 4) having the reference numerals 6, 411 to 414 and the mixers 407 to 410 will be described below.

The band-pass filters 403 and 411 have a characteristic of passing the frequency components of 2f ₁ -f ₂ out of the above-mentioned four waves and blocking the other three waves. Similarly, the bandpass filter 404,412 has the property of passing only frequency components of f _1, the band-pass filter 405,41
3 has a characteristic to pass only frequency components of f _2, bandpass filter 406,414 has the property of passing only the frequency component of 2f ₂ -f _1.

The mixers 407 to 410 receive LO (Local) signals of the same frequency. Of the input to the input terminal 401 signal, the frequency component mixer 407 of 2f-f _2, the frequency component of f ₁ is the mixer 40
8, the frequency component of f ₂ at mixers 409, 2f ₂ -f ₁
Are selectively down-converted by the mixer 410 and then combined, and output from the output terminal 302.

By down-converting each frequency in this manner, down-conversion can be performed even when the signal has a wide band. However, as shown in FIG. A configuration in which the pass filter is omitted is also possible.

Although the phases φ _3L and φ _{3U of the} distortion do not change due to the down-conversion described above, if the group delay of each signal path is different, correction must be made at the time of calculation. Therefore, a training unit for performing training for measuring the group delay of each path is provided in advance, and more accurate distortion measurement can be performed by performing such training.

Although the third-order intermodulation distortion has been described as an example, the fifth-order intermodulation distortion can be measured with a similar circuit configuration.

(Embodiment 2) Next, Embodiment 2
The configuration and operation of the low-distortion power amplifier according to the present embodiment will be described with reference to FIG.

The distortion phase measuring device 505 includes:
The above-described distortion phase measuring apparatus according to the first embodiment is used.

The signal input to the input terminal 501 is input to the power amplifier 504 after the signal is previously distorted by the predistortion compensation circuit 503. However, a part of the signal distorted in advance is input to the distortion phase measuring device 505.

The signal input to the power amplifier 504 is amplified there, a part of which is input to the distortion phase measuring device 505 and the distortion amplitude measuring means 506, and the other is output from the output terminal 502.

The outputs of the distortion phase measuring device 505 and the distortion amplitude measuring means 506 are input to the control means 507, which controls the predistortion compensation circuit 503 so that the distortion generated from the power amplifier 504 is minimized. Control.

More specifically, the distortion phase measuring device 50
5. The pre-distortion compensation circuit 503 controls to add a distortion having the same amplitude and opposite phase as the distortion signal obtained by the distortion amplitude measuring means 506. By performing such control, the pre-distortion compensating circuit 503 can be controlled such that the distortion of the signal output from the output terminal 502 quickly becomes the minimum distortion.

(Embodiment 3) Next, Embodiment 3
The configuration and operation of the low distortion power amplifier according to the present embodiment will be described with reference to FIG.

The distortion phase measuring device 614 includes:
The above-described distortion phase measuring apparatus according to the first embodiment is used.

The signal input to the input terminal 601 is distributed by the distribution circuit 603, and one of the signals is supplied to the vector adjustment circuit 604.
, And amplified by the power amplifier 605, and the other is input to the delay circuit 606.

The output of the power amplifier 605 is
7, one is input to the delay circuit 609, the other is synthesized with the output of the delay circuit 606 in the synthesis circuit 608, and only the distortion component is extracted.

The extracted distortion signal passes through a vector adjustment circuit 610 and is amplified by a power amplifier 611.
09 and the output of the 612 synthesis circuit 612.

At this time, by controlling the vector adjustment circuit 610 to make the distortion signals have the same amplitude and opposite phase, the distortion component contained in the output of the delay circuit 609 is suppressed. The output is a signal with suppressed distortion.

However, if the distortion signals input to the combining circuit 612 are not in the same phase and opposite phase conditions, the amount of distortion suppression deteriorates.

Therefore, a part of the output of the synthesizing circuit 612 is input to the distortion phase measuring device 614 and the distortion amplitude measuring means 615 by the distribution circuit 613, and the first and second embodiments are used.
The measurement of the distortion phase and distortion amplitude is performed as described in 2.

The measurement result is input to the control means 616, and the control means 616 controls the vector adjustment circuit 610 based on the input measurement result so that the distortion generated from the synthesis circuit 612 is minimized.

More specifically, the vector adjustment circuit 610
Is controlled so that distortion having the same amplitude and opposite phase as the distortion signal obtained by the distortion phase measuring device 614 and the distortion amplitude measuring means 616 is added to the input of the synthesis circuit 612.

Thus, the vector adjustment circuit 610 can be controlled such that the distortion of the signal output from the output terminal 602 becomes the minimum distortion at high speed.

As described above, the distortion phase measuring apparatus according to the present invention comprises, for example, a time waveform detecting means for detecting a time waveform of a signal and an output of the time waveform detecting means for detecting the detected time waveform. Analog-to-digital conversion means for converting an analog signal to a digital signal, and a frequency-domain conversion means connected to an output of the analog-to-digital conversion means for converting a time-domain waveform into a frequency-domain waveform by Fourier transform, A phase calculator connected to an output of the frequency converter and calculating a phase of the distortion, wherein magnitudes and phases of the distortion generated on the high frequency side and the distortion generated on the low frequency side are different. Even in such a case, the phase of the distortion can be measured.

Further, the distortion phase measuring apparatus of the present invention comprises, for example, a down-conversion means for down-converting the frequency of a signal, and a time-converted signal for detecting a time waveform of the signal, which is connected to an output of the down-conversion means. A time waveform detector, connected to an output of the time waveform detector, an analog-to-digital converter for converting a detected time waveform from an analog signal to a digital signal, and connected to an output of the analog-to-digital converter; Frequency domain converting means for converting a time domain waveform into a frequency domain waveform by Fourier transform, and a phase calculating means connected to an output of the frequency converting means for calculating a phase of distortion. As a feature, it is particularly effective when the signal frequency is high and analog-to-digital conversion is difficult.

Also, the downconverter of the present invention is connected to, for example, an input terminal, first to fourth mixer circuits connected to the input terminal, and outputs of the first to fourth mixer circuits, respectively. First to fourth band-pass filters, and output terminals connected to the first to fourth band-pass filters. Four waves having the same frequency interval are input to the input terminals, Signal is down-converted by the first mixer circuit, filtered by the first band-pass filter, and the signal of the second lowest frequency is down-converted by the second mixer circuit,
The second highest frequency signal is filtered by the second band pass filter, the second highest frequency signal is down-converted by the third mixer circuit, and then filtered by the third band pass filter, and the highest frequency signal is processed by the fourth mixer. After being down-converted by the circuit, it is filtered by a fourth band-pass filter, and the outputs of the first to fourth band-pass filters are connected to output terminals.

Also, the down converter of the present invention may be configured such that, for example, an input terminal, first to fourth band-pass filters connected to the input terminal, and outputs of the first to fourth band-pass filters. First to fourth mixer circuits respectively connected thereto; fifth to eighth bandpass filters respectively connected to the outputs of the first to fourth mixer circuits; and the fifth to eighth bandpass filters. An output terminal connected to a filter is provided, and four waves having the same frequency interval are input to the input terminal, and a signal having the lowest frequency is filtered by a first band-pass filter, and then filtered by a first mixer circuit. Down-converted, unnecessary signals are removed by the fifth band-pass filter, the second lowest frequency signal is filtered by the second band-pass filter, and then down-converted by the second mixer circuit. After being filtered, unnecessary waves are removed by a sixth band-pass filter, the second highest frequency signal is filtered by a third band-pass filter, and then down-converted by a third mixer circuit. Unnecessary waves are removed by the seventh band-pass filter, and the signal with the highest frequency is filtered by the fourth band-pass filter, down-converted by the fourth mixer circuit, and then by the eighth band-pass filter. Unnecessary waves are removed, and with these configurations, down conversion is possible even if the signal has a wide band.

The distortion phase measuring apparatus according to the present invention is, for example, the distortion phase measuring apparatus described above, wherein the down converter is the down converter described above, and the signal has a high frequency and a wide band. It is effective in the case.

Further, the distortion phase measuring apparatus according to the present invention is a distortion phase measuring apparatus as described above, which has a function of correcting the group delay time difference of each path by performing training, for example. If the group delay times of the paths are different, the difference is detected and corrected. As a result, even when the group delay time of each path is different, the phase of the distortion can be measured with high accuracy.

In the distortion phase measuring apparatus according to the present invention, for example, when the signals input to the time waveform detecting means are four waves having the same frequency interval, the phase of the signal having the lowest frequency and the phase of the signal having the highest frequency are Is defined by the difference between the phase of the signal of the second lowest frequency and the phase of the signal of the second highest frequency, the calculation method of the phase calculation means However, the phase of the lowest frequency signal is given by the sum of the instantaneous phase of the lowest frequency signal and the instantaneous phase of the second highest frequency at a certain time. The phase of the signal having the highest frequency is obtained by subtracting twice the phase of the signal having the highest frequency from the sum of the instantaneous phase of the signal having the highest frequency and the instantaneous phase having the second lowest frequency at a certain time.
The distortion phase measuring device described above, wherein the distortion phase is measured by subtracting twice the instantaneous phase of the second highest frequency.

Further, the low distortion power amplifier of the present invention comprises, for example, a pre-distortion compensating circuit, a power amplifier connected to an output of the pre-distortion compensating circuit, and a power amplifier connected to an output of the power amplifier. A distortion phase measuring device, a distortion amplitude measuring device for measuring an amplitude of distortion connected to an output of the power amplifier, and a control device, wherein an output signal from the distortion phase measuring device is the control device. And the output signal from the distortion amplitude measurement means is input to the control means, and the control means is output from the power amplifier based on the measurement results of the distortion phase measurement device and the distortion amplitude control means. The predistortion compensation circuit is controlled so that signal distortion is reduced, and a power amplifier with high efficiency and low distortion can be realized.

The low distortion power amplifier according to the present invention is a low distortion power amplifier comprising, for example, a predistortion compensation circuit and a power amplifier connected to an output of the predistortion compensation circuit. The phase of the distortion of the power amplifier is measured using the above-described distortion phase measuring device, and the phase of the distortion of the pre-distortion compensating circuit is adjusted using the above-described distortion phase measuring device so as to be in the opposite phase. Thus, a power amplifier with high efficiency and low distortion can be easily realized.

The low-distortion power amplifier of the present invention comprises, for example, a first distribution circuit and a first distribution circuit connected to one output of the first distribution circuit for controlling the amplitude and phase of a signal. Vector adjustment circuit, a first power amplifier connected to the output of the first vector adjustment circuit, a second distribution circuit connected to the first power amplifier, and the first distribution circuit A first delay circuit connected to the other output;
A first combining circuit having a first input connected to the first delay circuit, one output of the second distribution circuit, and another input of the first combining circuit being connected, A second delay circuit connected to the other output of the second distribution circuit, a second synthesis circuit having one input connected to the output of the second delay circuit, and the first synthesis circuit A second vector adjustment circuit connected to the output of the second power amplifier connected to the second vector adjustment circuit, one input is connected to the output of the second delay circuit, the second The output of the second power amplifier is a feedforward amplifier connected to the other output terminal of the second synthesis circuit, and a third distribution circuit connected to the output of the feedforward amplifier,
The above-described distortion phase measurement device connected to one output of the third distribution circuit, and a distortion amplitude measurement unit for measuring the amplitude of the distortion connected to one output of the third distribution circuit. , Control means, wherein an output signal from the distortion phase measurement device is input to the control means, an output signal from the distortion amplitude measurement means is input to the control means, and the control means And controlling the second vector adjustment circuit such that distortion of a signal output from the second synthesis circuit is reduced based on a measurement result of the apparatus and the distortion amplitude control means. In the feedforward amplifier, the characteristic of maximum distortion suppression can be obtained at high speed.

The transforming means of the present invention is the frequency domain transforming means 105 in the above-described embodiment. However, the present invention is not limited thereto, and the conversion means of the present invention may be any means as long as it is a means for performing a conversion using a Fourier transform on a digital signal having a distortion component.

In the present embodiment described above, the time-domain waveform of the input signal having a distortion component input from the outside is detected as an analog signal by the time waveform detector 103 in the present embodiment. The analog signal was a digital signal that was subjected to analog / digital conversion by the analog / digital conversion means 104.
However, the present invention is not limited to this, and the digital signal of the present invention may be any digital signal having a distortion component. Therefore, the time waveform detection means 103 and / or the analog-to-digital conversion means 104 may be provided separately from the distortion phase measurement device.

In the above-described embodiment, the input signal of the present invention is such that the signal component having the lowest frequency and the signal component having the highest frequency are distortion components.
The input signal had four signal components having the same frequency interval. However, the present invention is not limited to this.
In short, it may be an input signal having an arbitrary number of signal components input from the outside. For example, the frequency f ₁ ,
A distortion component and a frequency of a frequency f _L (<f ₁ ) generated by a signal having three signal components of f ₂ and f ₃ (f ₁ <f ₂ <f ₃ ) being amplified by a power amplifier or the like. f _U
An output signal from a power amplifier to which a distortion component (> f ₃ ) is added may be input as an input signal to the distortion phase measurement apparatus of the present invention. It goes without saying that the amount of phase shift can be measured as described above.

The distortion component of the present invention is the third-order intermodulation distortion in the above-described embodiment. However, the present invention is not limited to this.
Second-order intermodulation distortion or seventh-order intermodulation distortion may be used. As in the case of the above-described embodiment, for example, when a signal having two signal components of frequencies f ₁ and f ₂ (f ₁ <f) is amplified by a power amplifier or the like, the fifth-order intermodulation distortion Is the frequency 3f outside the third-order intermodulation distortion
₁ -2f _2, 3f ₂ appear to -2f _1. And the phase shift amounts φ _5L and φ _5U of these distortion components are

[0072]

## EQU4 ## φ _5L = 2Φ (ω ₂ , t) −3Φ (ω ₁ , t) + Φ
(3ω ₁ -2ω ₂ , t)

[0073]

[Number 5] _{φ 5U = 2Φ (ω 1,} t) -3Φ (ω 2, t) + Φ
(3ω ₂ −2ω ₁ , t) is calculated.

The calculating means of the present invention is the phase calculating means 106 in the above-described embodiment.
However, the present invention is not limited to this, and the calculation means of the present invention may be any means as long as it is a means for calculating the amount of phase shift of the distortion component of the present invention based on the result of conversion by the conversion means of the present invention.

According to the present invention, the functions of all or a part of the above-described distortion phase measuring apparatus, down converter, and low distortion power amplifier (or apparatus, elements, circuits, units, etc.) of the present invention are executed by a computer. And a program that operates in cooperation with a computer.

It should be noted that some of the means (or devices, elements, circuits, units, etc.) of the distortion phase measuring apparatus, downconverter, and low distortion power amplifier of the present invention are some of the plurality of means. Or some of the functions of one means.

Also, some of the devices (or elements, circuits, units, etc.) of the distortion phase measurement device, down converter, and low distortion power amplifier of the present invention may use some of the plurality of devices. This means, or means, some means (or elements, circuits, units, etc.) in one device, or some functions in one means.

The present invention also includes a computer-readable recording medium on which the program of the present invention is recorded. Further, one usage form of the program of the present invention may be a form in which the program is recorded on a computer-readable recording medium and operates in cooperation with the computer. One usage of the program of the present invention may be a mode in which the program is transmitted through a transmission medium, read by a computer, and operates in cooperation with the computer. The recording medium includes a ROM and the like, and the transmission medium includes a transmission medium such as the Internet, light, radio waves, and sound waves.

The configuration of the present invention may be realized by software or hardware.

[0080]

As is apparent from the above description,
The present invention has an advantage that, for example, even when the magnitudes of the distortion components are different from each other, the phase shift amount of the distortion components can be measured with high accuracy.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a distortion phase measurement device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a distortion phase measurement apparatus having down-conversion means 203 according to Embodiment 1 of the present invention.

FIG. 3 shows a mixer 303 according to the first embodiment of the present invention.
Of down-conversion means having the band-pass filters 306 to 306 and the band-pass filters 307 to 310

FIG. 4 is a diagram illustrating bandpass filters 403 to 406 and 411 to 414 and a mixer 4 according to the first embodiment of the present invention.
Configuration diagram of down-conversion means having 07-410

FIG. 5 is a configuration diagram of a low distortion power amplifier according to a second embodiment of the present invention.

FIG. 6 is a configuration diagram of a low distortion power amplifier according to Embodiment 3 of the present invention.

FIG. 7 is a configuration diagram of a conventional distortion phase measurement device.

[Explanation of symbols]

Reference Signs List 101 input terminal 102 output terminal 103 time waveform detecting means 104 analog-digital converting means 105 frequency domain converting means 106 phase calculating means 201 input terminal 202 output terminal 203 down-converting means 204 time waveform detecting means 205 analog-digital converting means 206 frequency domain converting means 207 Phase calculation means 301 Input terminal 302 Output terminal 303, 304, 305, 306 Mixer 307, 308, 309, 310 Bandpass filter 401 Input terminal 402 Output terminal 403, 404, 405, 406, 411, 412, 4
13, 414 Band-pass filters 407, 408, 409, 410 Mixer 501 Input terminal 502 Output terminal 503 Predistortion compensation circuit 504 Power amplifier 505, 506 Distortion phase measuring device 507 Control means 601 Input terminal 602 Output terminal 603, 607, 613 Distribution circuit 604, 610 Vector adjustment circuit 605, 611 Power amplifier 606, 609 Delay circuit 608, 612 Synthesis circuit 614 Distortion phase measurement device 615 Distortion amplitude measurement means 616 Control means 701 Input terminal 702 Output terminal 703 Distribution circuit 704 Power amplifier 705 Vector Adjustment circuit 706 Delay circuit 707 Synthesis circuit

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) H04L 25/02 302 H04L 25/02 302C (72) Inventor Kaoru Ishida 1006 Odakadoma, Kadoma City, Osaka Matsushita Electric F term in Sangyo Co., Ltd. (reference) 2G030 AA01 AB04 AD08 AG05 5K029 AA01 KK03 KK26

Claims (12)

[Claims] A conversion unit for performing a conversion using a Fourier transform on a digital signal having a distortion component; and calculating a phase shift amount of the distortion component based on a result of the conversion by the conversion unit. And a calculating means for calculating the distortion phase. 2. The digital signal having a distortion component is a digital signal in which a time-domain waveform of an input signal having a distortion component input from the outside is detected as an analog signal, and the analog signal is subjected to analog / digital conversion. The distortion phase measuring device according to claim 1, wherein 3. The conversion using a Fourier transform on a digital signal having a distortion component is a conversion of a digital signal into a frequency domain waveform using a Fourier transform on a time domain waveform obtained by analog / digital conversion of the digital signal. The distortion phase measuring device according to claim 2. 4. The input signal having a distortion component inputted from the outside has four signal components having equal frequency intervals, and the distortion component is a signal having the lowest frequency among the four signal components. And calculating the phase shift amount of the distortion component means calculating the instantaneous phase of the four signal components using the waveform in the frequency domain, and (1) calculating the instantaneous phase of the four signal components. The phase shift amount of the low frequency signal component is calculated from the sum of the calculated instantaneous phase of the lowest frequency signal component and the instantaneous phase of the second highest signal component of the calculated frequency. Frequency 2
(2) calculating the amount of phase shift of the signal component having the highest frequency with the instantaneous phase of the signal component having the highest frequency. The calculated value is obtained by subtracting twice the instantaneous phase of the second highest signal component of the calculated frequency from the sum of the calculated frequency and the instantaneous phase of the second lowest signal component. 3. The distortion phase measuring device according to 3. 5. The calculated amount of phase shift of the signal component having the lowest frequency is the instantaneous phase of the signal component that is the second lowest in the calculated frequency and the instantaneous phase of the signal component having the lowest frequency.
When the instantaneous phase of the second highest signal component is equal, the difference between the instantaneous phase of the calculated lowest frequency signal component and the instantaneous phase of the second lowest signal component of the calculated frequency, The calculated phase shift amount of the signal component having the highest frequency is the instantaneous phase of the second lowest signal component of the calculated frequency and the instantaneous phase of the second highest signal component of the calculated frequency. 5. The distortion phase measuring apparatus according to claim 4, wherein the difference is the difference between the calculated instantaneous phase of the signal component having the highest frequency and the calculated instantaneous phase of the signal component having the second highest frequency. 6. The distortion phase according to claim 2, further comprising a down-converter for down-converting the frequency of the signal component of the externally input signal in order to generate the digital signal having the distortion component. measuring device. 7. The distortion phase measurement apparatus according to claim 6, further comprising training means for performing training for correcting a group delay time difference of a path through which a signal component of the input signal input from the outside passes. 8. A conversion means for performing a conversion using a Fourier transform on a digital signal having a distortion component,
A digital signal to be subjected to the conversion in a distortion phase measuring device having a calculating means for calculating a phase shift amount of the distortion component based on a result of the conversion is converted into an input signal having a distortion component input from the outside. In order to detect the time domain waveform of the signal as an analog signal and generate the analog signal by performing analog / digital conversion,
A downconverter for downconverting the frequency of a signal component of the input signal input from the outside in advance. 9. A semiconductor device comprising: first to fourth mixer circuits; and first to fourth bandpass filters for respectively inputting signals from the first to fourth mixer circuits, wherein the first to fourth bandpass filters are input from the outside. The input signal having a distortion component is
It has four signal components having the same frequency interval, and among the four signal components, (1) the signal component having the lowest frequency is down-converted by the first mixer circuit, Filtered by a filter,
(2) The signal component having the second lowest frequency is down-converted by the second mixer circuit, and then filtered by the second band-pass filter. (3) The signal component having the second highest frequency is: After being down-converted by the third mixer circuit, the signal is filtered by the third band-pass filter. (4) The signal component having the highest frequency is down-converted by the fourth mixer circuit, and 9. The downconverter of claim 8, wherein the downconverter is filtered by a four bandpass filter. 10. A first to fourth band-pass filter, first to fourth mixer circuits for respectively inputting signals from the first to fourth band-pass filters, and the first to fourth band-pass filters. Fifth to eighth bandpass filters each performing signal input from a mixer circuit, wherein the input signal having a distortion component input from the outside is:
The first mixer circuit has four signal components having the same frequency interval, and among the four signal components, (1) a signal component having the lowest frequency is filtered by the first band-pass filter, and then the first mixer circuit Is down-converted, unnecessary waves are removed by the fifth band-pass filter,
(2) The signal component having the second lowest frequency is filtered by the second band-pass filter, then down-converted by the second mixer circuit, and an unnecessary wave is removed by the sixth band-pass filter. (3) a signal component having the second highest frequency is filtered by the third band-pass filter and then down-converted by the third mixer circuit;
Unwanted waves are removed by the seventh bandpass filter,
(4) The signal component having the highest frequency is filtered by the fourth band-pass filter, then down-converted by the fourth mixer circuit, and unnecessary waves are removed by the eighth band-pass filter. Item 10. The down converter according to item 8. 11. A low distortion power amplifier using the distortion phase measuring device according to claim 1. 12. The distortion phase measuring apparatus according to claim 1,
Conversion means for performing a conversion using a Fourier transform on a digital signal having a distortion component, and calculation means for calculating a phase shift amount of the distortion component based on a result of the conversion by the conversion means A program that causes a computer to function as all or part of the program.