JP2002290166A - Amplifier unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize efficient distortion compensation in an amplifier unit for compensating a distortion, which occurs in an amplifier for amplifying a transmission signal. SOLUTION: The amplifier 4 amplifies the transmission signal, distortion level detecting means 5-9 detects the distortion level of a distortion-detecting frequency from the output signal of the amplifier 4, and distortion compensating means 9 and 2 compensate the distortion of the transmission signal prior to amplification by the amplifier 4, so as to reduce the distortion level to be detected. In this case, distortion-detecting frequency control means 9 and 5 change the distortion-detecting frequency to be used by the distortion level detecting means and adjust the distortion level to be detected by the level- detecting means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an amplifying device for compensating for distortion generated in an amplifier for amplifying a transmission signal, and more particularly, to changing a distortion detecting frequency for detecting a distortion level to an appropriate frequency position. The present invention relates to an amplifier that realizes efficient distortion compensation.

[0002]

2. Description of the Related Art For example, W-CDMA (Wide-band Code D)
ivision Multiple Access)
In a base station device (CDMA base station device) provided in a mobile communication system adopting the mobile communication system as a mobile communication system, it is necessary to make a radio signal reach a physically distant mobile station device (CDMA mobile station device). Therefore, it is necessary to greatly amplify a signal to be transmitted by an amplifier and output the signal.

However, since the amplifier is an analog device, there is an amplification limit. This amplification limit is also called a saturation point. After the saturation point, even if the power input to the amplifier increases, the output power does not increase and becomes almost constant, and the output becomes non-linear. Then, non-linear distortion is generated by the non-linear output. For this reason, in the transmission signal before amplification by the amplifier, the signal component outside the desired signal band is suppressed to a low level by the band limiting filter.
Non-linear distortion occurs in the signal after passing through the amplifier, and the signal component leaks out of the desired signal band (adjacent channel).

For example, since the transmission power is high in the base station apparatus as described above, the magnitude of the leakage power to such an adjacent channel is strictly specified.
Such adjacent channel leakage power (ACP: Adjacent C)
A major issue is how to reduce hannel leak power.

[0005] Next, an example of a transmission power amplifying unit with distortion compensation provided in a conventional base station apparatus will be described to reduce the adjacent channel leakage power as described above. FIG. 9 shows a configuration example of such a transmission power amplifier with distortion compensation, and an operation example thereof will be described.

That is, in the transmission power amplification unit with distortion compensation, the transmission signals (I and Q components) generated by the baseband signal generation unit 51 are input to a vector adjustment unit (pre-distortion unit) 52 and a power measurement unit 59. The transmission signal input to the vector adjustment unit 52 is distortion-compensated by the vector adjustment unit 52. Here, the vector adjustment unit 52 is generally composed of a complex multiplier, and in accordance with the control from the control unit 58 described below, the characteristic of the amplitude-phase plane is set to be the inverse characteristic of the nonlinear characteristic of the amplifier 54 described below. By giving the characteristic (that is, the inverse characteristic) to the transmission signal as a distortion compensation characteristic, the transmission signal is distortion-compensated.

The transmission signal whose distortion has been compensated by the vector adjustment unit 52 is up-converted from the baseband band to the carrier frequency band by the modulation unit 53,
And is supplied to an antenna (not shown). Also,
In the amplifier 54, distortion occurs when amplifying the transmission signal,
The amplifier with distortion compensation is provided with a feedback system for detecting the remaining amount of the distortion in order to observe whether or not distortion compensation has been properly performed.

The feedback system includes a local frequency generator 55, a demodulator 56, an A / D (Analog to Digital)
A configuration in which a converter 57 is provided, and a part of the output signal (amplified signal) of the amplifier 54 supplied to the antenna described above is extracted by, for example, the directional coupler 60 and input to the demodulation unit 56. Has become.

In the feedback system, the amplified signal input from the directional coupler 60 to the demodulation unit 56 is demodulated using the local signal input from the local frequency generation unit 55 to the demodulation unit 56, and the demodulation is performed. The signal is converted from an analog signal to a digital signal by the A / D converter 57, and the digital signal is input to the control unit 58.

The power measuring section 59 detects the power (transmission power) of the transmission signal input from the baseband signal generation section 51 and notifies the control section 58 of the detection result. The control unit 58 is, for example, a DSP (Digital Sign).
al Processor), detects the amount of residual distortion from the digital signal input from the A / D converter 57, and performs appropriate distortion compensation by the vector adjustment unit 52 based on the detection result. The vector controller 52 is controlled.

As a method of detecting the amount of distortion by the control unit 58, for example, a digital signal input from the A / D converter 57 and a signal output from the baseband signal generation unit 51 are compared to each other to detect the amount of distortion. Or a method of detecting the amount of distortion by performing fast Fourier transform (FFT) processing on a digital signal input from the A / D converter 57, for example.

In order to reduce the amount of distortion obtained by such a method, a distortion compensation characteristic corresponding to the transmission power notified from the power measurement unit 59 is generated by the control unit 58 and used for distortion compensation. Is controlled. As described above, in the transmission power amplification unit with distortion compensation shown in FIG. 9 described above, by performing appropriate distortion compensation on the distortion generated in the amplifier 54, an efficient transmission power amplification process is realized. Adjacent channel leakage power is greatly reduced.

However, in the configuration of the conventional transmission power amplifying unit with distortion compensation as shown in FIG. 9, for example, it is difficult to increase the detection accuracy of the adjacent channel leakage power (distortion generated in the amplifier). There is a problem that a system for detecting the adjacent channel leakage power becomes complicated.

That is, when distortion compensation is performed with the above configuration, the difference between the desired transmission signal power and the distortion power becomes 50d.
Since it is more than B, it is necessary to accurately detect a small residual distortion amount, such as 1 / 100,000, with respect to a desired transmission signal power, and it is difficult to increase the detection accuracy. The power difference of 50 dB is caused by the demodulation unit 5
6 and the dynamic range of the A / D converter 57 is 50 dB
This indicates that the above is necessary, and the operating frequency and the sampling frequency required for the A / D converter 57 become severe, so that the system becomes complicated. Also,
For example, when dealing with a wideband signal such as the W-CDMA system, the sampling frequency in the A / D converter 57 becomes very large. As a result, the demodulation unit 56 and the A / D converter 57 There is a problem that it becomes expensive and it is difficult to create a device (transmission power amplification unit with distortion compensation).

In general, a transmission signal amplified by the amplifier 54 may include a plurality of carrier signals having different frequencies, for example. There is no one that detects distortion and compensates for it with high accuracy.

To solve such a problem, for example, in an amplifying device described in Japanese Patent Application No. 2000-025995, an amplifier for amplifying a transmission signal in a configuration for compensating for distortion generated by the amplifier for amplifying the transmission signal is disclosed. A distortion detection unit that removes a signal of a frequency corresponding to a transmission signal from an output signal of the amplifier to detect distortion of a predetermined detection frequency generated by the amplifier, and reduces distortion detected by the distortion detection unit. And a distortion compensating means for compensating distortion of the transmission signal before amplification by the amplifier or the output signal of the amplifier.

In this amplifying apparatus, for example, the transmission signal includes a plurality of carrier signals having different frequencies,
A distortion detection unit configured to mix a signal of a detection frequency positioned between a frequency of a carrier signal to be subjected to distortion compensation and a frequency of a carrier signal adjacent to the carrier signal and an output signal of the amplifier; A low-pass filter that removes the adjacent carrier signal from the signal, and detects distortion generated in the amplifier from an output signal of the low-pass filter.

In this amplifying apparatus, for example, the detection frequency is a frequency at which both carrier signals between the frequency of a carrier signal to be subjected to distortion compensation and the frequency of a carrier signal adjacent to the carrier signal do not exist. The frequency located at the center of the interval is used. In this amplifier, for example, a common amplifier that can collectively amplify a plurality of carrier signals having different frequencies is used as the amplifier. Also, this amplifying device, for example,
It is provided in a base station device, a relay amplification device, and the like.

In such an amplifying apparatus, base station apparatus, or relay amplifying apparatus, for example, when compensating for distortion generated in an amplifier for amplifying a transmission signal, the accuracy of distortion detection can be improved. It is possible to reduce the cost and size of the device.

In order to solve the above problem, for example, in an amplifying apparatus described in Japanese Patent Application No. 2000-026029, at least one carrier signal of a plurality of carrier signals having different frequencies is transmitted. As a configuration that compensates for distortion generated in the amplifier that amplifies the transmission signal, an amplifier that amplifies the transmission signal,
A plurality of frequencies located between respective adjacent carrier signals can be switched as detection frequencies, and a carrier signal having a frequency adjacent to the switched detection frequency is removed from an output signal of the amplifier to perform the detection generated by the amplifier. And a distortion compensator for compensating the transmission signal before amplification by the amplifier or the output signal of the amplifier so that the distortion detected by the distortion detector is reduced.

In this amplification device, for example, a carrier signal detecting means for detecting a carrier signal included in the transmission signal is provided, and the distortion detecting means is provided only for a frequency adjacent to the frequency of the carrier signal detected by the carrier signal detecting means. Is switched as the detection frequency. Further, in this amplifier, for example, the carrier signal detecting means can switch the frequency of a plurality of carrier signals, a mixer for mixing a signal of the switched frequency and an output signal of the amplifier, and an output signal of the mixer for the frequency. And a determination unit for determining whether or not a carrier signal corresponding to the transmission signal is included, and detects a carrier signal included in the transmission signal based on the determination result.

In this amplifying apparatus, for example, the distortion detecting means includes a mixer for mixing a signal of the detection frequency and an output signal of the amplifier, and a carrier signal having a frequency adjacent to the detection frequency from the mixer output signal. And a distortion of the detection frequency generated by the amplifier from the output signal of the low-pass filter.

Further, in this amplifying apparatus, for example, a frequency located at the center of a frequency interval where both carrier signals between two adjacent carrier signals do not exist is used as the plurality of frequencies to be switched as detection frequencies. Can be In this amplifier, for example, a common amplifier that can amplify a plurality of carrier signals having different frequencies collectively is used as the amplifier. This amplifying device is provided in, for example, a base station device or a relay amplifying device.

In such an amplifying apparatus, base station apparatus, relay amplifying apparatus, or the like, for example, at least one carrier signal of a plurality of carrier signals having different frequencies is used as a transmission signal and an amplifier that amplifies the transmission signal is used. When compensating for distortion, it is possible to improve the accuracy of distortion detection corresponding to the carrier signal of each frequency,
Further, it is possible to reduce the cost and size of the device.

[0025]

However, for example, in the conventional transmission power amplifier with distortion compensation as shown in FIG. 9, when detecting the distortion included in the signal output from the amplifier 54, Is fixed at a fixed frequency position, for example, when the amount of distortion at each frequency position changes in accordance with the progress of the distortion compensation processing, the frequency is detected. There is a problem that the distortion amount fluctuates greatly and stable distortion compensation cannot be performed with high accuracy, and a problem that the dynamic range of a device to be used must be increased.

The present invention has been made to solve such a conventional problem. When compensating for distortion generated in an amplifier for amplifying a transmission signal, an appropriate distortion detection frequency for detecting a distortion level is used. It is an object of the present invention to provide an amplifier capable of realizing efficient distortion compensation by changing to a frequency position.

[0027]

In order to achieve the above object, an amplifier according to the present invention compensates for distortion generated in an amplifier when a transmitting signal is amplified by the amplifier as follows. That is, the amplifier amplifies the transmission signal, the distortion level detecting means detects the distortion level of the distortion detecting frequency from the output signal of the amplifier, and the distortion compensating means detects the distortion level before amplification by the amplifier so that the detected distortion level is reduced. In this case, the distortion detection frequency control means changes the distortion detection frequency used by the distortion level detection means to change the distortion level detected by the distortion level detection means. adjust.

Accordingly, since the distortion detection frequency is changed to adjust the distortion level to be detected, for example, by changing the distortion detection frequency for detecting the distortion level to an appropriate frequency position, stable distortion compensation is performed. , Accurate distortion compensation can be performed, and the dynamic range of a device to be used can be made relatively small, whereby efficient distortion compensation can be realized.

Here, various signals may be used as the transmission signal. Various amplifiers may be used as the amplifier. For example, not only a single amplifier but also a combination of a plurality of amplifiers may be used. As the distortion level to be detected, for example, adjacent channel leakage power (ACP) can be used.

As a mode for compensating the distortion so that the detected distortion level is reduced, for example, it is preferable to use a mode for compensating the distortion so as to minimize the detected distortion level. As long as it is effective, various precisions of distortion compensation may be used.

The distortion compensation of the transmission signal before amplification by the amplifier or the output signal of the amplifier includes, for example, a distortion compensation of the transmission signal before amplification of the transmission signal before the transmission signal is amplified by the amplifier, After the transmission signal is amplified by the amplifier, the transmission signal after the amplification (that is, the output signal of the amplifier) is distortion-compensated, and the transmission signal is transmitted both before and after the transmission signal is amplified by the amplifier. A mode in which the signal is distortion-compensated can be used. As long as distortion compensation can be performed effectively in practical use, for example, another processing circuit may exist between the circuit for performing distortion compensation and the amplifier.

Further, the distortion can be compensated by, for example, applying a distortion having a characteristic opposite to that of the distortion generated in the amplifier to a transmission signal before or after amplification by the amplifier. Note that the distortion generated in the amplifier includes, for example, amplitude distortion and phase distortion.

As a method of changing the distortion detection frequency, for example, a method of changing the distortion detection frequency to a discrete value may be used. For example, the distortion detection frequency may be changed to a continuous value. Ways may be used.
Also, as a method of adjusting the detected distortion level,
Various methods may be used, for example, a method of adjusting a distortion level detected to be a maximum level not exceeding a predetermined threshold or a maximum level not exceeding a predetermined threshold, and a method of adjusting a distortion level, for example, to a predetermined level. For example, a method of adjusting the detected distortion level can be used.
Here, as the predetermined level, for example, not only a single level value but also a level range having a width, for example, may be used.

In the amplifying device according to the present invention, the distortion generated in the amplifier when the transmission signal is amplified by the amplifier is compensated as follows. That is, the amplifier amplifies the transmission signal, and the signal level detection means within the distortion monitor band changes the detection frequency within the distortion monitor band to detect the signal level of the output signal of the amplifier at the detection frequency. The frequency determination means determines a distortion detection frequency based on the detection result, the distortion level detection means detects a distortion level of the distortion detection frequency determined from the output signal of the amplifier, and the distortion compensation means detects the distortion. The transmission signal before amplification by the amplifier or the output signal of the amplifier is distortion-compensated so that the level is reduced.

Therefore, the signal level of the output signal of the amplifier is detected within the distortion monitor band, and the distortion detection frequency is determined based on the detection result. For example, the distortion detection frequency for detecting the distortion level is appropriately set. By changing the frequency position to a stable frequency,
Accurate distortion compensation can be performed, and the dynamic range of a device to be used can be made relatively small, so that efficient distortion compensation can be realized.

Here, the distortion monitor band is a band in which distortion detection is performed. Also, as the distortion monitor band,
Various bands may be used, and for example, a band used in signal communication can be used. As a method of changing the detection frequency, for example, a method of continuously changing the detection frequency in the distortion monitor band may be used. For example, the detection frequency may be discretely changed in the distortion monitor band. Ways may be used. When the detection frequency is continuously changed in the distortion monitor band, a frequency spectrum of the output signal of the amplifier in the distortion monitor band is obtained.

As a method of determining the distortion detection frequency based on the detection result of the signal level of the output signal of the amplifier in the distortion monitor band, various methods may be used. A frequency position to be detected, a level of a distortion component existing at a frequency position near the frequency position, a method of determining a distortion detection frequency at which the level of the distortion component detected based on the detection result increases, and the like. Can be used.

In the amplifying device according to the present invention, as a preferred embodiment, a common amplifier capable of amplifying a plurality of carrier signals having different frequencies collectively is used as the amplifier. Therefore, by using such a common amplifier, an efficient amplification process can be realized, for example, as described in an embodiment described later.

According to the present invention, as a preferred embodiment, a base station apparatus or a relay amplifying apparatus having the amplifying apparatus as described above may be configured as an application object particularly requiring distortion compensation of an amplifier. it can. Therefore, in the base station device and the relay amplification device including the amplification device according to the present invention, it is possible to obtain various effects as described above,
Efficient distortion compensation can be realized.

[0040]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An amplifying device according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an example of the configuration of the amplifying device of the present example. This amplifying device has a configuration in which the present invention is applied to, for example, the amplifying device described in the embodiment of Japanese Patent Application No. 2000-026029 described above. ing. Further, the transmission signal of the present example includes at least one carrier signal among a plurality of carrier signals having different frequencies. Specifically, for example, the transmission signal may be one carrier signal depending on a communication situation. Only, or may include two or more carrier signals.

First, a schematic configuration example of the amplifier of the present embodiment shown in FIG. 1 will be described. The characteristic components according to the present invention will be described later. As shown in the figure, the amplifying device of the present example includes a baseband signal generating unit 1 for generating a transmission signal (I component and Q component), a vector adjusting unit (predistortion unit) 2 for performing distortion compensation, and A modulator 3 for converting (up-converting) a transmission signal from a baseband band to a carrier frequency band, an amplifier 4 for amplifying the transmission signal to required transmission power, and a part of an output signal (amplified signal) of the amplifier 4 Is input to a mixer 7 described later, and the remaining part is supplied to an antenna (not shown).
For example, a synthesizer 5 that can switch and output signals of a plurality of different carrier frequencies (local frequencies) under the control of a control unit 9 described below, and a directional coupler 11 using signals from the synthesizer 5. Mixer 6 for converting (down-converting) the signal of the above to a low frequency band
A low-pass filter (LPF) 7 for removing unnecessary signals from a signal down-converted by the mixer 6 with predetermined filter characteristics described later;
An A / D converter 8 for converting an output signal of the LPF 7 into a digital signal (digital value); a control unit 9 composed of, for example, a DSP for controlling a distortion compensation process performed by the vector adjustment unit 2; A power measuring unit 10 for detecting the power of a transmission signal (baseband signal) input from the generating unit 1 is provided.

Here, the configuration and operation of the above-described baseband signal generator 1, vector adjuster 2, modulator 3, amplifier 4, directional coupler 11, and power measuring unit 10 are shown, for example, in FIG. In the following, the synthesizer 5 that constitutes the feedback system of the present example will be mainly described.
The configuration and operation of the mixer 6, the LPF 7, the A / D converter 8, and the control unit 9 will be described in detail.

That is, in this example, the distortion (signal located in the channel adjacent to the carrier signal to be subjected to distortion compensation) generated in the amplifier 4 is obtained by the mixer 6 using, for example, a direct conversion method.
The synthesizer 5 has a function of generating a signal having the same frequency as the center frequency of the signal desired to be obtained by the mixer 6 and outputting the signal to the mixer 6. As described above, the frequency (local frequency) of the signal output by the synthesizer 5 of the present example in the distortion detection processing is not the center frequency of the transmission signal originally desired to be transmitted, but the frequency of the distortion generated in the amplifier 4. That is, the frequency is located near the carrier signal to be subjected to distortion compensation.

The synthesizer 5 of the present embodiment uses a plurality of frequencies located at the center between the center frequency of each carrier signal and the frequency of a carrier signal adjacent to the frequency as a distortion detection frequency in accordance with the control of the control unit 9. It is switchable and outputs a signal of the switched frequency to the mixer 6.

The mixer 6 mixes the signal input from the synthesizer 5 and the output signal of the amplifier 4 input from the directional coupler 11 to down-convert the output signal to a baseband band and down-converts the output signal. And a function of outputting the converted signal to the LPF 7.

The LPF 7 receives the signal output from the mixer 6 and sends only a signal component of a predetermined low frequency band among the frequency components constituting the signal to the A / D converter 8 as a band-limited signal. It has a function to output. In order to realize accurate distortion detection, the LPF 7 reduces the level of an unnecessary carrier signal (adjacent carrier signal described above) having a relatively large level from the output signal of the mixer 6, for example, to reduce the level. Is required to leave a large distortion in the signal after the band limitation.

The A / D converter 8 has a function of converting a signal input from the LPF 7 into a digital signal and outputting the digital signal to the control unit 9. Here, the signal input to the A / D converter 8 of this example includes, for example, only the distortion component and does not include the transmission signal (carrier signal) as described above. In such a point that the dynamic range of the converter 8 can be made relatively small, the price of the A / D converter 8 can be reduced.

The control section 9 detects the level of distortion (in this example, a part of the distortion) contained in the output signal of the amplifier 4 based on the digital signal input from the A / D converter 8, The power of the transmission signal notified from the power measurement unit 10 is detected, and based on these detection results, the amplifier 4
Has a function of controlling the distortion compensation processing by the vector adjustment unit 2 so that the level of the distortion included in the output signal of (1) is reduced (to approach zero). Further, the control unit 9 of the present example has a function of, for example, switching a frequency of a signal generated by the synthesizer 5 by calculating a control signal for controlling the synthesizer 5 and outputting the control signal to the synthesizer 5. ing.

Further, the amplifying apparatus of this embodiment has a function of detecting a carrier signal included in a transmission signal (carrier sensing function) and a distortion with respect to only a distortion detection frequency determined according to the frequency of the detected carrier signal. It has a function of performing detection, and these functions will be described below.

That is, in general, the amplifier is not provided with information as to which frequency carrier signal is included in the transmission signal to be currently processed.
In the configuration described above, for example, distortion detection is performed for all frequencies in the distortion monitor band other than the frequency of the carrier signal. However, since the frequency of a large number of distortion components is roughly determined by the frequency of the existing carrier, it is useless to perform distortion detection for all frequencies (that is, frequency positions where it is considered that there is no distortion).

Therefore, the synthesizer 5 provided in the amplifying device of the present embodiment has not only a function of switchingably generating a distortion detection frequency for detecting distortion, for example, but also a function of switching.
For example, according to the control of the control unit 9, the control unit 9 also has a function of generating a switchable signal of the frequency of each carrier signal and outputting the signal of the frequency to the mixer 6. Further, the control unit 9 of the present example sequentially switches the frequency of the signal generated by the synthesizer 5 to, for example, the frequencies of all the carrier signals that can be included in the transmission signal, while the carrier signal of any frequency is included in the transmission signal. Has a function of detecting whether

Specifically, for example, when a signal having the same frequency as a certain carrier signal is output from the synthesizer 5 and the carrier signal is included in the transmission signal, the control unit 9 controls the LPF 7 and the A Since the carrier signal component is detected from the digital signal input via the / D converter 8, it can be determined that the carrier signal is present in the transmission signal. On the other hand, in such a case, when the carrier signal is not included in the transmission signal, the control unit 9 detects the carrier signal component from the digital signal input via the LPF 7 and the A / D converter 8. Therefore, it can be determined that the carrier signal does not exist in the transmission signal.

When the pass bandwidth of the LPF 7 is much narrower than the bandwidth of the carrier signal as in this example, the control section 9 cannot obtain a complete waveform of the carrier signal. Since the purpose is to determine whether or not each carrier signal exists in the transmission signal, the control unit 9
It is not always necessary to obtain an accurate signal waveform of the carrier signal.

Next, an example of a schematic operation performed by the amplifying apparatus of this embodiment will be described. The characteristic operation part according to the present invention will be described later. That is, in the amplifying device of this example, the transmission signals (I component and Q component) generated by the baseband signal generation unit 1 are input to the vector adjustment unit 2 and the power measurement unit 10 and input to the vector adjustment unit 2. The transmission signal is distortion-compensated by the vector adjustment unit 2 under the control of the control unit 9.

The transmission signal whose distortion has been compensated for by the vector adjustment unit 2 is up-converted from the baseband band to the carrier frequency band by the modulation unit 3 and then amplified by the amplifier 4 and supplied to an antenna (not shown). Here, distortion is generated when the amplifier 4 amplifies the transmission signal. Also,
A part of the output signal (amplified signal) of the amplifier 4 supplied to the above-described antenna is extracted by the directional coupler 11 having a small loss for the signal radiated from the antenna, for example, and input to the mixer 6. .

In the feedback system, the amplified signal input from the directional coupler 11 to the mixer 6 and the local signal input from the synthesizer 5 to the mixer 6 (frequency signal for detecting a carrier signal, (A frequency signal for detecting distortion) is mixed by the mixer 6, and the mixed signal passes through the LPF 7. For example, only the carrier signal component included in the signal and the distortion component included in the signal are removed. The acquired data is input to the A / D converter 8. In the A / D converter 8, a signal input from the LPF 7 is converted into a digital signal, and the digital signal is input to the control unit 9.

The power measuring section 10 detects the power (transmission power) of the transmission signal input from the baseband signal generation section 1 and notifies the control section 9 of the detection result. The control unit 9 first controls, for example, the synthesizer 5 to detect a carrier signal component from the digital signal input from the A / D converter 8, and specifies a carrier signal included in the transmission signal based on the detection result. I do. Then, the control unit 9 detects the remaining distortion amount from the digital signal input from the A / D converter 8 only for the frequency that is considered to have a large distortion component in accordance with the frequency of the carrier signal included in the transmission signal. At the same time, the transmission power notified from the power measurement unit 10 is detected, and based on these detection results, the vector adjustment unit 2 is controlled so that appropriate distortion compensation is performed by the vector adjustment unit 2.

As described above, in the amplifying apparatus of the present embodiment, the control having the function of amplifying the transmission signal and the function of setting the frequency outside the desired signal band as the distortion detection frequency and setting it in the synthesizer 5 are provided. A mixer 9 for mixing a signal such as a distortion detection frequency to be set and an output signal of the amplifier 4, and an LP for removing an out-of-band signal such as the distortion detection frequency from the output signal of the mixer 6
An F7 and a vector adjustment unit 2 for distortion-compensating the transmission signal before amplification by the amplifier 4 so as to reduce the level of the distortion component detected from the output signal of the LPF 7 are provided.

With such a configuration, in the amplifying apparatus of this embodiment, at least one carrier signal of a plurality of carrier signals having different frequencies is used as a transmission signal, and distortion generated by an amplifier that amplifies the transmission signal is compensated. For example, even when the level of the distortion included in the output signal of the amplifier 4 is smaller than the level of the carrier signal (the carrier signal having a frequency adjacent to the distortion detection frequency) included in the output signal, Since the distortion generated in the amplifier 4 is detected with high accuracy corresponding to the carrier signal of each frequency (for example, each of all the carrier signals included in the transmission signal), and appropriate distortion compensation is performed for the distortion. Very accurate and highly reliable distortion compensation processing can be realized. Further, in the amplifying device of this example, it is possible to significantly reduce power consumption, reduce the cost and size of the device, and easily implement a circuit for detecting distortion.

Specifically, in the amplifying device of this embodiment,
For example, in a feedback system, distortion at a frequency position adjacent to the frequency of each carrier signal to be subjected to distortion compensation (narrow band adjacent channel leakage power) or IM3
(3rd-Order Inter-Modulati
on), etc., and an LPF for realizing this.
7 is excellent in that it is used.

In a preferred embodiment of the amplifying apparatus of the present embodiment, a frequency located at the center between the center frequencies of two adjacent carrier signals is output from the synthesizer 5 as a local frequency for distortion detection (distortion detection frequency). Therefore, distortion detection with the carrier signal removed may be easily performed. Further, in the amplifying apparatus of this example, as a preferable mode, for example, an L-band having a narrow pass band characteristic equal to or less than a bandwidth obtained by subtracting a bandwidth per carrier signal from a frequency interval between center frequencies of adjacent carrier signals.
PF7 is used.

Further, in the amplifying device of the present embodiment, a carrier signal included in a transmission signal is detected, and only the frequency adjacent to the frequency of the detected carrier signal, that is,
Since distortion detection is performed only for frequencies at which distortion is expected to exist, efficient distortion detection can be realized. In a preferred embodiment of the amplification device of the present example, distortion detection and carrier signal detection are performed using a common synthesizer 5, a common mixer 6, and the like.

Next, with reference to FIGS. 2 and 3, as an example of a characteristic configuration and an operation example of the amplifying device according to the present invention,
An example of a method of calculating and adjusting a distortion detection frequency for detecting distortion by the control unit 9 will be described. In the control unit 9 of this example,
The distortion detection frequency is changed in the following manner (1) to (8) to detect the distortion component level of the distortion detection frequency. Here, in the control unit 9 of the present example, by controlling the synthesizer 5 with a control signal, the frequency of the signal generated by the synthesizer 5 and output to the mixer 6 can be changed, for example, at intervals of a predetermined value Δf. .

In this example, a configuration is shown in which it is determined whether the distortion component level is equal to or greater than a predetermined threshold value or less than the threshold value, and the frequency for distortion detection is changed in accordance with each determination result. It is also possible to determine whether the level exceeds a predetermined threshold value or lower than the threshold value, and change the distortion detection frequency in accordance with each determination result.

(1) The distortion component level of the frequency (f + Δf) detected by increasing the distortion detection frequency f used immediately before by a predetermined value Δf is the frequency detected by the distortion detection frequency f used immediately before. If the level is higher than the distortion component level of f and is equal to or greater than the threshold value, the distortion detection frequency (f + Δf) is decreased by a predetermined value Δf in the next detection of the distortion component level. (2) The distortion component level of the frequency (f + Δf) detected by increasing the distortion detection frequency f used immediately before by a predetermined value Δf is the distortion of the frequency f detected by the distortion detection frequency f used immediately before. If it is higher than the component level and less than the threshold, the distortion detection frequency (f + Δf) is increased by a predetermined value Δf in the next detection of the distortion component level.

(3) The distortion component level of the frequency (f + Δf) detected by increasing the distortion detection frequency f used immediately before by a predetermined value Δf is the frequency detected by the distortion detection frequency f used immediately before. If the distortion component level is smaller than the distortion component level of f and is equal to or greater than the threshold, the distortion detection frequency (f + Δf) is increased by a predetermined value Δf in the next detection of the distortion component level. (4) The distortion component level of the frequency (f + Δf) detected by increasing the distortion detection frequency f used immediately before by a predetermined value Δf is the distortion of the frequency f detected by the distortion detection frequency f used immediately before. If it is lower than the component level and less than the threshold, the distortion detection frequency (f + Δf) is decreased by a predetermined value Δf in the next detection of the distortion component level.

(5) The distortion component level of the frequency (f-Δf) detected by reducing the distortion detection frequency f used immediately before by a predetermined value Δf is detected by the distortion detection frequency f used immediately before. If the level is higher than the distortion component level at the frequency f and is equal to or higher than the threshold, the distortion detection frequency (f-Δf) is increased by a predetermined value Δf in the next detection of the distortion component level. (6) The distortion component level of the frequency (f−Δf) detected by reducing the distortion detection frequency f used immediately before by a predetermined value Δf is the frequency f detected by the distortion detection frequency f used immediately before. If it is higher than the distortion component level and less than the threshold value, the distortion detection frequency (f-Δf) is decreased by a predetermined value Δf in the next detection of the distortion component level.

(7) The distortion component level of the frequency (f−Δf) detected by decreasing the distortion detection frequency f used immediately before by a predetermined value Δf is detected by the distortion detection frequency f used immediately before. If the level is lower than the distortion component level at the frequency f and is equal to or higher than the threshold, the distortion detection frequency (f-Δf) is decreased by a predetermined value Δf in the next detection of the distortion component level. (8) The distortion component level of the frequency (f−Δf) detected by decreasing the distortion detection frequency f used immediately before by a predetermined value Δf is the frequency f detected by the distortion detection frequency f used immediately before. If the distortion component level is smaller than the threshold and is smaller than the threshold, the distortion detection frequency (f-Δf) is increased by a predetermined value Δf in the next detection of the distortion component level.

Specifically, FIGS. 2A to 2D show:
An example of the level of a distortion component that is input from the A / D converter 8 to the control unit 9 and detected is shown. The horizontal axis represents the frequency f for distortion detection, and the vertical axis represents the level of the distortion component. It is. Also, in FIGS. 6A to 6D, predetermined threshold values regarding the distortion component level are indicated by dotted lines.
This threshold value is set in the control unit 9 in advance, for example.

First, as shown in FIG. 7A, when a distortion component level less than the threshold value is detected at the distortion detection frequency f, the distortion detection frequency f is increased, for example, by a predetermined value Δf. If the detection result of the distortion component level at the increased distortion detection frequency (f + Δf) is such that the distortion component level increases and is less than the threshold as shown in FIG. The use frequency (f + Δf) is further increased by a predetermined value Δf. When the detection result of the distortion component level at the increased frequency for distortion detection (f + 2Δf) is as shown in FIG.
This distortion detection frequency (f + 2Δf) is reduced by a predetermined value Δf. Then, the reduced distortion detection frequency (f
In (+ Δf), the distortion component level is adjusted to the maximum level in the variation range of the distortion detection frequency, as shown in FIG.

Various values may be set as the above-mentioned threshold value. For example, a value is set so that the signal level detected as the distortion component level does not include the level of the carrier signal. You. In other words, since the carrier signal level is usually higher than the distortion component level, simply changing the distortion detection frequency so that the detected distortion component level becomes the maximum will detect the carrier signal level as the distortion component level. Can be considered. In order to prevent this, in this example, a threshold for separating the carrier signal level and the distortion component level is set, and a level lower than the threshold is regarded as a level of the distortion component being detected, while a level lower than the threshold is regarded as being detected. It is assumed that the detection result includes the level of the carrier signal and that the detection result is not adopted.

Further, an example of a method of changing a band for measuring ACP (ACP measurement band) as a distortion detection frequency will be described, taking as an example a case where adjacent channel leakage power (ACP) of a carrier signal is detected as a distortion component level. . As shown in FIGS. 3A to 3D, the ACP
Since the level increases as the frequency is closer to the frequency of the carrier signal, the level decreases as the frequency moves away from the frequency of the carrier signal, and the level changes continuously with a change in frequency. It is effective to change the distortion detection frequency (ACP measurement band). 3A to 3D, the horizontal axis represents the frequency f, and the vertical axis represents the signal level.

FIGS. 3 (a) and 3 (b) show an example of the case of a conventional system in which the distortion detection frequency is fixedly set. In this conventional system, FIG. As shown, the same ACP measurement band is used both in the initial convergence stage of distortion compensation where the ACP is relatively large and in the compensation stage of distortion compensation where the ACP is compensated and becomes relatively small as shown in FIG. Is used, the ACP detected in the correction stage is much smaller than the ACP detected in the initial convergence stage. For this reason, when measuring or comparing ACP, a wide dynamic range is required to obtain the same accuracy in the initial convergence stage and the correction stage. For example, an A / D converter (A / D converter) The size of the container 8) becomes large and expensive.

On the other hand, FIGS. 3C and 3D show an example of the case of the system of the present example (the proposed system) in which the distortion detection frequency is appropriately changed as described above. ,
In the proposed method of this example, A
By changing the CP measurement band, the ACP measurement band is relatively moved away from the frequency of the carrier signal in the initial convergence stage of the distortion compensation where the ACP is relatively large, as shown in FIG. In the distortion compensation correction step in which the ACP is compensated and becomes relatively small as shown in (1), the ACP measurement band is made relatively close to the frequency of the carrier signal, so that the detected ACP is made almost constant. Is performed. Therefore, for example, the detected A is adjusted so that the dynamic range is optimized.
By adjusting the CP, the size of the A / D converter 8 can be reduced.

In the present embodiment, an example of changing the distortion detection frequency has been described. However, the present invention is not limited to this. For example, the frequency of a signal generated by the synthesizer 5 and output to the mixer 6 may be controlled. Various methods may be used so that the dynamic range of the A / D converter 8 can be set to be relatively small and efficiency can be improved.

As described above, in the amplifying apparatus of this embodiment, the level of the distortion component of the distortion detection frequency located between the frequencies of the adjacent carrier signals is calculated from the output of the low-pass filter 7 by the A / D conversion.
By detecting through the converter 8 and comparing the distortion component level with a threshold, and controlling the synthesizer 5 based on the magnitude relationship between the distortion component level and the threshold to increase or decrease the frequency for distortion detection, Adjust the level of the detected distortion component.

Specifically, for example, as described above, immediately after the distortion compensation is started, the ACP at a frequency relatively far from the carrier signal is measured according to the fact that the ACP near the carrier signal is relatively large, and the distortion is measured. ACP is compensated
When the ACP becomes smaller, the ACP of a frequency relatively close to the carrier signal is measured in response to the fact that the measured value becomes very small when the ACP at a frequency distant from the carrier signal is measured. Thus, for example, the ACP that is A / D-converted by the A / D converter 8 has a substantially constant level immediately after the distortion compensation is started and when the distortion compensation is performed, and the dynamic range of the A / D converter 8 is reduced, for example. A stable and accurate A even if it is smaller than before
CP can be detected.

As described above, in the amplifier of the present embodiment, the efficiency of the A / D converter 8 can be easily improved by providing the threshold value for the detected distortion component level and determining the distortion detection frequency. Accordingly, it is possible to realize a reduction in the size and cost of the device.

Here, in this example, the amplifier 4 for amplifying the transmission signal corresponds to the amplifier according to the present invention, and the distortion generated by this amplifier 4 is to be compensated. Further, in this example, the function of the synthesizer 5, the mixer 6, the LPF 7, the A / D converter 8, and the control unit 9 detecting the distortion level of the distortion detection frequency from the output signal of the amplifier 4 provides the distortion level referred to in the present invention. Detection means is configured. In this example, ACP is detected as the distortion level.

In this embodiment, the function of the control unit 9 controlling the vector adjustment unit 2 so as to reduce the distortion level detected by the distortion detection means and to compensate the distortion of the transmission signal before amplification by the amplifier 4. Thus, the distortion compensating means according to the present invention is constituted. Instead of compensating the distortion of the transmission signal before amplification as in this example, it is also possible to compensate the distortion of the output signal of the amplifier 4, for example. Also, as the operating frequency, it is possible to perform distortion compensation on a signal in a carrier frequency band, for example, instead of performing distortion compensation on a signal in a baseband band as in this example.

In this embodiment, the control section 9 controls the synthesizer 5 to change the frequency for distortion detection used by the distortion level detecting means to adjust the distortion level detected by the distortion level detecting means. By function
The distortion detection frequency control means according to the present invention is constituted.

In the amplifying apparatus of this embodiment, as a preferred embodiment, the distortion is detected by using the direct conversion method. However, for example, a general double superheterodyne method may be used. Further, for example, the configuration of the vector adjustment unit 2 that performs distortion compensation, the presence or absence of the power measurement unit 10, and the like may be arbitrary.

Next, an amplifier according to a second embodiment of the present invention will be described with reference to the drawings. A schematic configuration example of the amplifying apparatus of this embodiment is, for example, the same as that shown in FIG. 1 of the first embodiment, and the amplifying apparatus of this embodiment has a baseband like the one shown in FIG. Signal generator 1 and vector adjuster 2
A modulator 3, an amplifier 4, a synthesizer 5, a mixer 6, an LPF 7, an A / D converter 8, a controller 9,
A power measurement unit 10 and a directional coupler 11 are provided. In this example, for convenience of explanation, the processing units 1 to 11 are denoted by the same reference numerals as those of the processing units 1 to 11 shown in FIG.

In the following, for example, a description of the same configuration and operation as those of the amplifying device shown in the first embodiment will be omitted, and
As an example of a characteristic configuration and an operation example of the amplifying device of this example according to the present invention, an example of a method of determining a distortion detection frequency will be described with reference to FIG. In this example, the measurement band of the ACP is used as the distortion detection frequency. Here, FIG. 4A shows an example of an actual frequency spectrum output from the amplifier 4, and FIG. 4B shows the frequency of a signal input from the A / D converter 8 to the control unit 9. An example of the frequency spectrum is shown, and the horizontal axis of these graphs shows the frequency f, and the vertical axis shows the signal level.

The controller 9 detects the level of the distortion component based on the digital signal input from the A / D converter 8 as in the case of the first embodiment. In this case, in this case, As shown in FIG. 2A, while continuously changing the detection frequency set in the synthesizer 5 from, for example, a low frequency position to a high frequency position over the entire distortion monitor band set in advance, for example, The signal level at each frequency position is detected. Then, in the control unit 9, A
Based on the digital signal input from the / D converter 8,
For example, detection of the presence or absence of a desired signal (carrier signal) and detection of a distortion component in the entire distortion monitor band are performed. In this example, a frequency band used for communication is used as the distortion monitor band.

Here, since the power ratio between the desired signal and the distortion component is usually as large as 30 dBm or more, the method of detecting the presence or absence of the desired signal is, for example, as shown in FIG. A / D in the frequency band where
Since the digital signal input from the converter 8 to the control unit 9 frequently overflows, it is possible to easily detect the position of the desired signal assuming that the desired signal exists in the overflowed frequency band. Note that whether or not the digital signal input from the A / D converter 8 to the control unit 9 has overflowed is determined, for example, when the digital signal exceeds a predetermined threshold (hereinafter, referred to as a desired signal threshold). It is possible to make a determination based on whether the maximum digital value has been reached.

The control section 9 can set a distortion detection frequency to be set in the synthesizer 5 based on, for example, a result of detection of the presence or absence of a desired signal. Since it is possible to grasp the whole within the monitor band, the same effect as that of the FFT can be obtained. For this reason, even when the level of the distortion component is not uniform within the distortion monitor band for ACP or IM3 as shown in FIG.
It is possible to improve the efficiency of the / D converter 8 and the efficiency of distortion compensation.

In FIG. 9B, for example, a threshold value of the distortion component level similar to that shown in the first embodiment is shown by a dotted line, and a distortion determined based on the threshold value is shown. An example of the optimum measurement point of the detection frequency is shown. In distortion compensation, it is not always necessary to measure the level of a desired signal. Therefore, as described in this example, simply detecting the presence or absence of a desired signal based on overflow is not enough to determine a distortion detection frequency. Yes, distortion compensation performance can be improved.

With such a configuration, in the amplifying apparatus of the present embodiment, for example, the level of the signal input from the low-pass filter 7 to the control unit 9 via the A / D converter 8 is detected for the whole of the distortion monitor band. To detect whether a desired signal exists at each frequency position based on whether the detected signal level is equal to or higher than a predetermined desired signal threshold, and to detect a distortion component level based on these detection results. Is determined. As a method of determining the distortion detection frequency, for example, a method similar to that shown in FIGS. 2 and 3 of the first embodiment is used.

More specifically, for example, in the first embodiment, the ACP of only one side of the desired signal is measured, and the distortion detection frequency (ACP measurement band) within the distortion detection band (ACP measurement band) of the one side. Is increased or decreased to determine the frequency for distortion detection, but in practice there is no correlation between ACP and IM3 on both sides of the desired signal, and AC
It has become clear that there is a difference between the levels of P and IM3. Therefore, in this example, the presence or absence of a desired signal and the distortion component level (ACP) located on both sides of the desired signal are detected while scanning all frequencies within the distortion monitor band, and the distortion component levels on both sides of the detected desired signal are detected. The frequency band having the highest signal level in the frequency band other than the frequency band in which the desired signal exists is determined as a distortion detection band (ACP measurement target band) by comparing the magnitudes of The optimum distortion component level detection is realized by determining the distortion detection frequency by increasing or decreasing the distortion detection frequency (ACP measurement band) in the same manner as shown in FIGS. 2 and 3 above. did.

In this example, scanning of the detection frequency is continuously performed. For example, the frequency band having the highest signal level outside the frequency band of the desired signal is always the ACP.
The ACP measurement target band is updated so as to be used as the measurement target band. Further, in this example, when the frequency for distortion detection is increased or decreased in the same manner as shown in FIG. 2 or FIG. The timing of reaching the frequency band to be used is used, and the scanning process of the detection frequency in the entire distortion monitor band is performed again at such a timing.

Therefore, in the amplifying apparatus according to the present embodiment, the distortion detection frequency is determined based on the result of detecting the frequency position where the desired signal exists, and therefore, for example, a predetermined frequency within the frequency band used for communication. Efficient distortion compensation can be performed over the entire distortion monitor band. Further, in the amplifying apparatus of the present example, since the ACP is detected over the entirety of the distortion monitor band, the efficiency of the A / D converter 8 can be improved.

Further, in the amplifying apparatus of this embodiment, a desired signal (carrier signal) included in the transmission signal can be easily detected by setting the desired signal threshold as described above, for example. If the signal is included, since the distortion detection frequency can be set at a frequency position near the frequency position of each carrier signal, for example, after detecting a distortion component level in a lower frequency band than the desired signal, It is possible to easily detect a distortion component level on the frequency band side higher than the desired signal or a distortion component level at a frequency position near another desired signal. Therefore, for example, even when there is a level difference between the desired signals, the distortion component level can be set at a frequency position where the distortion component level is large, and the distortion component level can be detected. Performance can be improved.

Here, in this example, the control section 9 controls the synthesizer 5 to change the detection frequency within the distortion monitor band, and changes the signal level of the detection signal of the output signal of the amplifier 4 to the mixer 6 or the like. The function of detecting via the LPF 7 and the A / D converter 8 constitutes a signal level detecting means in the distortion monitor band according to the present invention. In this example,
The function of the control unit 9 determining the distortion detection frequency based on the detection result of the distortion monitor in-band signal level detection means constitutes the distortion detection frequency determination means according to the present invention.

Next, a base station apparatus according to a third embodiment of the present invention will be described with reference to the drawings. In this example, W-CDMA
A base station apparatus that wirelessly communicates with a mobile station apparatus by adopting the scheme will be described as an example. FIG. 5 shows an example of the appearance of a casing constituting the base station apparatus of the present embodiment. As shown in FIG. 5, the base station apparatus of the present embodiment performs signal processing and control when roughly classified. It is composed of an MDE unit (wireless modulation / demodulation unit) and an amplifier unit provided with, for example, a common amplifier.

In the base station apparatus of this embodiment, the amplifier section is M
Although installed in the upper stage of the DE unit, for example, when the amplifier unit and the MDE unit are separately installed according to the installation location of the base station device, when they are arranged side by side, or when the amplifier unit is installed in the MDE In some cases, it may be installed at the lower part of the section.

FIG. 6 shows a schematic configuration example of the base station apparatus of this embodiment. As shown in the figure, the base station apparatus of the present example includes an interface unit 21 for communicating signals with another base station apparatus or the like via a wired transmission path, and a baseband signal processing unit. A baseband signal processing unit 22, a wireless transmission / reception unit 23 for transmitting / receiving a signal in a radio frequency band, for example, the first embodiment or the second
A transmission power amplifying unit 24 having a distortion compensation function similar to that of the amplifying device shown in the embodiment and amplifying a transmission signal by an amplifier.
An antenna unit 25 for transmitting and receiving a radio signal using an antenna 26 described later, a control unit 27 for controlling the antenna 26 and various processes performed by the processing units 21 to 26 are provided.

Here, in this example, for example, the interface unit 21, the baseband signal processing unit 22, the radio transmitting / receiving unit 2
5 and the control unit 27 constitute the MDE unit shown in FIG. 5. For example, the transmission power amplifying unit 24 constitutes the amplifier unit shown in FIG.

Next, an example of processing performed by the base station apparatus of this example will be described. That is, in the transmission processing, for example, the baseband signal processing unit 22 performs baseband processing on a signal received from another base station device or the like via the interface unit 21 via a wired transmission path, and then performs the radio transmission / reception
3, the signal (transmission signal) in the radio frequency band is amplified by the transmission power amplifier 24, and the amplified signal is transmitted from the antenna 26 to the mobile station device or the like by the antenna unit 25. Transmit wirelessly.

In the receiving process, for example, a signal wirelessly transmitted from a mobile station device or the like is received by an antenna unit 25 via an antenna 26, and the received signal is received by a wireless transmitting / receiving unit 23, and then a baseband signal is received. The processing unit 22 performs baseband processing, and then transmits the received signal to another base station device or the like via the wired transmission path by the interface unit 21.

As described above, the base station apparatus of the present example has a distortion compensation function similar to that of the amplifying apparatus shown in the first embodiment or the second embodiment, for example, to compensate for the distortion generated in the amplifier. Therefore, the level of the distortion generated in the amplifier corresponding to the carrier signal of each frequency included in the transmission signal can be stably and accurately determined in the same manner as in the first and second embodiments. Since the distortion is well detected and appropriate distortion compensation is performed on the distortion, a very efficient distortion compensation process can be realized.

Further, as in the first and second embodiments, the base station apparatus of the present embodiment can realize a great reduction in power consumption and a reduction in required cost. Therefore, it is possible to reduce the price of the entire base station device and to reduce the size of the device. Specifically, for example, the power line for supplying power to the amplifier is made smaller than before, and the power supply equipment for supplying power to the entire base station device is reduced in price and size as compared with the past. It is possible to do.

In this example, the case where the present invention is applied to a base station apparatus adopting the CDMA scheme has been described. However, the present invention is applied to a base station apparatus adopting another communication scheme such as the TDMA scheme or the FDMA scheme. It is also possible to apply. Further, in this example, the case where the amplifying device shown in the first embodiment or the second embodiment is applied to the base station device has been described. However, such an amplifying device is, for example, a base station device and a mobile station device. It is also possible to apply the present invention to a relay amplifying device that relays communication between the devices.

Further, in the base station apparatus of the present example, as a preferred embodiment, the transmission signal is amplified by the common amplifier using the distortion compensation function according to the present invention as described above. The configuration example of the amplifier unit used will be described in comparison with a configuration example of an amplifier unit using a normal amplifier (here, an amplifier that is not a common amplifier).

First, FIG. 7 shows an example of the configuration of an amplifier section using an ordinary amplifier (an amplifier section for performing individual amplification). In this amplifier section, for example, different frequencies f1 and f2 are used.
Is separately amplified for each frequency, and then a method of combining amplified signals of the respective frequencies f1 and f2 is used. Specifically, the signal of the frequency f1 is amplified by the amplifier 31, while the signal of the other frequency f2 is amplified by the other amplifier 3.
2, and the two amplified signals are combined by the combiner 33. Here, in each of the amplifiers 31 and 32, distortion (adjacent channel leakage power) occurs due to the non-linearity.

In such an amplifier section, broadband synthesis is performed.
A loss of 3 dB occurs for the signal of. Therefore, for example, when the signals of the respective frequencies f1 and f2 are output at P [W] from the combiner 33, the respective amplifiers 3
In 1 and 32, the signals of the respective frequencies f1 and f2 are 2P
The output must be amplified to [W], and the amplifier efficiency will be １ ／ that of the single operation.

On the other hand, FIG. 8 shows a configuration example of an amplifier unit using a common amplifier (an amplifier unit for performing common amplification). In this amplifier unit, for example, a plurality of different frequencies f
A method of amplifying (common amplification) the signals of f1 and f2 collectively is used. Specifically, for example, in the amplifier section shown in FIG. 8, the signal obtained by combining the signals of two different frequencies f1 and f2 is equally distributed by the distributor 41 (not distribution for each frequency, but for example, power distribution). ), The respective divided signals are amplified by the respective common amplifiers 42 and 43, and then synthesized by the synthesizer 44. Here, in each of the common amplifiers 42 and 43, distortion (adjacent channel leakage power) is generated due to the non-linearity, and intermodulation distortion is generated due to signals of two different frequencies f1 and f2.

In such an amplifier section, for example, two outputs from the common amplifiers 42 and 43 are combined in parallel as described above. In such parallel combination, the same signal is combined, so that no combination loss occurs unlike the amplifier section shown in FIG. Therefore, for example, the synthesized signal of the two frequencies f1 and f2 is
In the case of outputting at [W], each of the common amplifiers 42 and 43 converts the composite signal of two frequencies f1 and f2 into P
It is sufficient to amplify the output to [W] and output it. This is preferable because the amplifier efficiency is higher than that of the amplifier section shown in FIG.

Although the intermodulation distortion occurs in the amplifier section shown in FIG. 8, such distortion can be easily eliminated by using the distortion compensation function according to the present invention. When considered as a whole, for example, when a plurality of different carrier signals (multi-carrier signals) are amplified, efficient amplification processing can be realized.

Here, the configurations of the amplifying device, the base station device, and the relay amplifying device according to the present invention are not necessarily limited to those described above, and various configurations may be used. Further, the application field of the present invention is not necessarily limited to the above-described fields, and the present invention can be applied to various fields. As an example, the application field of the amplifying device according to the present invention is not necessarily limited to a base station device or a relay amplifying device. It is also possible to apply to various devices such as a device (for example, a mobile phone terminal device or a PHS terminal device).

The various processes such as the distortion compensation process performed by the amplifying device, the base station device, and the relay amplifying device according to the present invention include, for example, the case where the processor is stored in the ROM in the hardware resources including the processor and the memory. The configuration may be such that the control is performed by executing the executed control program. For example, each functional unit for executing the processing may be configured as an independent hardware circuit. The present invention also provides a floppy (registered trademark) disk or a CD-ROM storing the above-mentioned control program.
The control program can be recognized as a computer-readable recording medium, and the control program can be input to the computer from the recording medium and executed by the processor, whereby the processing according to the present invention can be performed.

[0112]

As described above, according to the amplifier according to the present invention, the transmission signal is amplified by the amplifier, the distortion level of the distortion detection frequency is detected from the output signal of the amplifier, and the detected distortion level is reduced. The transmission signal before amplification by the amplifier or the output signal of the amplifier is distortion-compensated so as to be reduced, and in this case, the detected distortion level is adjusted by changing the distortion detection frequency used for detecting the distortion level. Therefore, for example, it is possible to perform stable distortion compensation, perform accurate distortion compensation, and relatively reduce the dynamic range of a device to be used, thereby achieving efficient distortion compensation.

Further, according to the amplifying device of the present invention, the transmission signal is amplified by the amplifier, the detection frequency is changed in the distortion monitor band, and the signal level of the output signal of the amplifier at the detection frequency is detected. A distortion detection frequency is determined based on the detection result, a distortion level of the determined distortion detection frequency is detected from an output signal of the amplifier, and transmission before amplification by the amplifier is performed so that the detected distortion level is reduced. Since the signal or the output signal of the amplifier is subjected to distortion compensation, for example, stable distortion compensation can be performed, accurate distortion compensation can be performed, and the dynamic range of a device to be used can be relatively small, and efficiency can be reduced. Dynamic distortion compensation can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration example of an amplification device according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining an example of a method of adjusting a distortion detection frequency according to the first embodiment of the present invention.

FIG. 3 is a diagram illustrating an example of a method of setting an ACP measurement band according to the first embodiment of the present invention.

FIG. 4 is a diagram for explaining an example of a method of determining an ACP measurement band according to a second embodiment of the present invention.

FIG. 5 is a diagram illustrating an example of an external appearance of a housing configuring a base station device according to a third embodiment of the present invention.

FIG. 6 is a diagram illustrating a schematic configuration example of a base station apparatus according to a third embodiment of the present invention.

FIG. 7 is a diagram illustrating a configuration example of an amplifier unit that performs individual amplification.

FIG. 8 is a diagram illustrating a configuration example of an amplifier unit that performs common amplification.

FIG. 9 is a diagram illustrating a configuration example of a transmission power amplification unit with distortion compensation according to a conventional example.

[Explanation of symbols]

1. baseband signal generation section, 2. vector adjustment section, 3. modulation section, 4, 31, 32,.
..Synthesizer, 6..Mixer, 7..Low-pass filter, 8.A / D converter, 9.Control unit, 10
..Power measuring section, 11 directional coupler, 21 ..
Interface section, 22 baseband signal processing section,
23 ··· Wireless transmission / reception unit, 24 ··· Transmission power amplification unit,
25 antenna section, 26 antenna, 27 control section, 33, 44 synthesizer, 41 distributor, 4
2, 43 ... common amplifier,

Continued on the front page (72) Inventor Kazuyoshi Sato 3- 14-20 Higashi-Nakano, Nakano-ku, Tokyo Inside Hitachi Kokusai Electric Co., Ltd. Kokusai Denki (72) Inventor Masaki Sudo 3-14-20 Higashinakano, Nakano-ku, Tokyo Hitachi Kokusai Electric Co., Ltd.F-term (reference) 5J090 AA01 AA41 CA21 FA17 GN02 GN05 KA00 KA32 KA34 KA42 KA53 KA55 KA68 MA11 QA04 SA14 TA01 TA03 5J091 AA01 AA41 CA21 FA17 KA00 KA32 KA34 KA42 KA53 KA55 KA68 MA11 QA04 SA14 TA01 TA03 5K022 EE01 EE21

Claims (2)

[Claims] An amplifier for compensating for distortion generated in an amplifier for amplifying a transmission signal, comprising: an amplifier for amplifying a transmission signal; and a distortion level detecting means for detecting a distortion level of a distortion detection frequency from an output signal of the amplifier. A distortion compensating means for compensating a transmission signal before amplification by an amplifier or an output signal of the amplifier so that a detected distortion level is reduced; and a distortion level by changing a distortion detection frequency used by the distortion level detecting means. An amplifier comprising: a distortion detection frequency control unit that adjusts a distortion level detected by the detection unit. 2. An amplifying apparatus for compensating for distortion generated in an amplifier for amplifying a transmission signal, comprising: an amplifier for amplifying a transmission signal; and an amplifier for amplifying an output signal of the amplifier by changing a detection frequency within a distortion monitor band. A distortion monitor in-band signal level detecting means for detecting a signal level of the frequency; a distortion detecting frequency determining means for determining a distortion detecting frequency based on the detection result; and a distortion detecting frequency determined from an output signal of the amplifier. And a distortion compensating means for compensating a transmission signal before amplification by an amplifier or an output signal of the amplifier so that the detected distortion level is reduced. Amplifying device.