JP2001217792A - Amplifying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve accuracy in distortion detection corresponding to the carrier signals of respective frequencies in an amplifying device or a base station device for compensating the distortion, which occurs in an amplifier 4 for amplifying a transmitting signal containing plural carrier signals. SOLUTION: Distortion detecting means 5-9 switch plural frequencies, which are located between respective adjacent carrier signals, as a frequency for detection and detect the distortion of the frequency for detection generated in the amplifier by removing a carrier signal having a frequency adjacent to the frequency for detection from the output signal of the amplifier, and distortion compensating means 9 and 2 compensate the distortion of the transmitting signal before amplification due to the amplifier so as to reduce the distortion to be detected. Besides, carrier signal detecting means 5-9 detect the carrier signals contained in the transmitting signal and the distortion detecting means switches only the frequency adjacent to the frequency of the detected carrier signal as a frequency for detection.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an amplifying apparatus for compensating for distortion generated in an amplifier for amplifying a transmission signal by using at least one of a plurality of carrier signals having different frequencies as a transmission signal. The present invention relates to a base station device and a relay amplification device provided with a simple amplification device, and more particularly to a technique for improving the accuracy of distortion detection corresponding to a carrier signal of each frequency.

[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, the output power becomes constant even if the power input to the amplifier increases, resulting in a non-linear output. Then, non-linear distortion is generated by the non-linear output.

FIG. 12 shows an example of the spectrum of a transmission signal before being input to the amplifier. FIG. 13 shows that the transmission signal is amplified by the amplifier when distortion compensation is not performed. 2 shows an example of the spectrum of a signal output from the oscilloscope. FIG. 12 and FIG.
The horizontal axis of the graph shown in Fig. 3 is frequency (unit is [kHz])
And the vertical axis indicates the power ratio (unit is [dB]).

As shown in FIG. 12, in a transmission signal before amplification, a signal component outside a desired signal band is suppressed to a low level by a band limiting filter, whereas as shown in FIG. In the signal after passing through the amplifier, distortion occurs and the signal component leaks out of the desired signal band (adjacent channel).

[0006] 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.

Next, an example of a transmission power amplifying unit with distortion compensation provided in a conventional base station apparatus will be described in order to reduce the above adjacent channel leakage power. FIG.
2 shows a configuration example of such a transmission power amplifying unit with distortion compensation, and its operation 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 according to the control from the control unit 58 described later, the characteristic of the amplitude-phase plane is set to be the inverse characteristic of the nonlinear characteristic of the amplifier 4 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 transmission modulation unit 53,
4 and supplied to an antenna (not shown). Also, distortion occurs when amplifying the transmission signal in the amplifier 54, and the amplifier with distortion compensation has a feedback system that detects the remaining amount of the distortion in order to observe whether the distortion compensation has been properly performed. Provided.

This feedback system has a local frequency generator 55, a demodulator 56 and an A / D converter 57, and a part of the output signal (amplified signal) of the amplifier 54 supplied to the antenna. Is taken out by, for example, a directional coupler and input to the demodulation unit 56.

In the feedback system, the amplified signal input from the directional coupler to the demodulator 56 is demodulated using the local signal input from the local frequency generator 55 to the demodulator 56, and the demodulated signal is Is converted from an analog signal to a digital signal by the A / D converter 57,
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. In this control, control is performed so that the distortion compensation characteristic corresponding to the transmission power notified from the power measurement unit 59 is used for distortion compensation.

As described above, the transmission power amplifying unit with distortion compensation shown in FIG. 14 performs an appropriate distortion compensation for the distortion generated by the amplifier 54, thereby achieving an efficient transmission power amplifying process. Has been realized. Here, FIG.
FIG. 5 shows an example of a spectrum of a signal output when a transmission signal is amplified by the amplifier 54 when such distortion compensation is performed. In this signal spectrum, adjacent channel leakage power is greatly reduced. .
The horizontal axis of the graph shown in FIG.
Hz]), and the vertical axis indicates the power ratio (unit: [dB]).

Next, some conventional techniques relating to the above-described distortion compensation will be described. First, for example, Japanese Patent Application Laid-Open No. 9-2941
In the digital wireless device described in Japanese Patent Publication No. 44 (hereinafter referred to as Reference 1), distortion compensation is performed using a feedback system similar to that shown in FIG. 14 described above. Similarly to the above, the required signal to be transmitted (ie, the original transmission signal) is down-converted together with the unnecessary signal generated in the adjacent channel (ie, the distortion generated by the amplifier), and all these signals are converted. Processing such as quadrature demodulation is performed.

Also, for example, in an auto-tracking type predistorter described in Japanese Patent Publication No. 63-10613 (hereinafter referred to as Reference 2), an amplifier using a feedback system similar to that shown in FIG. In this feedback system, the amplified signal including the transmission signal band is demodulated (that is, the baseband signal before modulation is reproduced) and the A / D Processing such as conversion is performed.

Although distortion compensation is not performed, the adjacent channel leakage power measuring device and method described in, for example, Japanese Patent Application Laid-Open No. 9-138251 (hereinafter referred to as Document 3) are similar to the above. , The signal of the carrier (that is, the signal corresponding to the required signal) is taken out together with the signal of the adjacent channel (that is, the signal corresponding to the unnecessary signal), and the signals are subjected to fast Fourier transform (FFT) to perform the adjacent channel leakage. The power ratio (power ratio between required signal and unnecessary signal) is measured.

[0017]

However, in the configuration of the conventional transmission power amplifying unit with distortion compensation as shown in FIG. 14, for example, the detection accuracy of adjacent channel leakage power (distortion generated in the amplifier) is increased. However, there is a problem that the system for detecting the adjacent channel leakage power becomes complicated.

That is, if the distortion is compensated by the above configuration, as shown in FIG. 15, for example, the difference between the desired transmission signal power and the distortion power becomes about 50 dB. It is necessary to accurately detect a small residual distortion amount such as 1 / 100,000 with respect to the signal power, and thus it is difficult to increase the detection accuracy. Further, the power difference of 50 dB indicates that the dynamic range of the demodulation unit 56 and the A / D converter 57 is required to be 50 dB or more, and the operating frequency and sampling frequency required for the A / D converter 57. Is also severe, and the system becomes complicated. Also, for example, W-CD
When dealing with a wideband signal like the MA method,
Since the sampling frequency in the A / D converter 57 becomes very large, as a result, the demodulation unit 56 and the A / D
The converter 57 is expensive, and it is difficult to create a device (transmission power amplifier with distortion compensation).

Further, from the viewpoint of the above-mentioned object of the present invention,
The devices and the like described in the above-mentioned references 1 to 3 will be considered. For example, in the device described in Document 1,
Where an A / D converter is required to digitize a signal, for example, a W-CD having a bandwidth of 20 MHz
When receiving the MA transmission signal, the A / D
The operating frequency of the converter is required to be higher than 80 MHz, which is not preferable. In addition, since the level difference between the desired transmission signal and the unnecessary distortion is about 50 dB to 60 dB as described above, there is a problem that it is difficult to cope with the dynamic range as described above.

Also, for example, the device described in the above-mentioned document 2 has the same problem as the device described in the above-mentioned document 1. In addition, for example, in the device described in the above-mentioned Document 3, it is necessary to perform measurement corresponding to all frequency bands including the frequency of a carrier and the frequency of an adjacent channel. Therefore, an expensive A / D converter is used. It is essential to use it, which is not preferable in terms of cost reduction of the apparatus.

In general, a transmission signal amplified by the amplifier 54 may include a plurality of carrier signals having different frequencies, for example. Since there is no device that detects the distortion and compensates with high accuracy, development of a device that realizes such desirable distortion compensation has been demanded.

The present invention has been made to solve such a conventional problem, and an amplifier for amplifying a transmission signal using at least one of a plurality of carrier signals having different frequencies as a transmission signal. Provided is an amplification device capable of improving the accuracy of distortion detection corresponding to a carrier signal of each frequency when compensating for distortion generated in a base station device, a base station device including such an amplification device, and a relay amplification device. The purpose is to: Further, in the amplifying device, the base station device, and the relay amplifying device according to the present invention, it is possible to reduce the cost and size of the device.

[0023]

In order to achieve the above object, an amplifying apparatus according to the present invention uses at least one carrier signal of a plurality of carrier signals having different frequencies as a transmission signal and converts the transmission signal to an amplifier. When amplifying is performed, distortion generated in the amplifier is compensated as follows. That is, the amplifier amplifies the transmission signal, the distortion detection means can switch a plurality of frequencies located between each adjacent carrier signal as a detection frequency,
A carrier signal having a frequency adjacent to the switched detection frequency is removed from the output signal of the amplifier to detect distortion of the detection frequency generated by the amplifier, and the distortion compensating means reduces distortion detected by the distortion detecting means. Thus, the transmission signal before amplification by the amplifier or the output signal of the amplifier is distortion-compensated.

Therefore, a plurality of frequencies as described above can be switched as the detection frequency, and a carrier signal having a frequency adjacent to the detection frequency is removed from the output signal of the amplifier to detect distortion. For example, even when the level of the distortion included in the output signal is lower than the level of the carrier signal (the carrier signal having a frequency adjacent to the detection frequency) included in the output signal, each of the carrier signals ( Corresponding to each of the detection frequencies), the distortion can be detected with high accuracy, whereby the accuracy of distortion compensation can be improved.

In the amplifying device according to the present invention, the carrier signal detecting means detects the carrier signal included in the transmission signal, and the distortion detecting means detects only the frequency adjacent to the frequency of the carrier signal detected by the carrier signal detecting means. Is switched as the detection frequency. Therefore, since distortion detection is performed only on the frequency adjacent to the frequency of the carrier signal included in the transmission signal, for example, the frequency adjacent to the frequency of the carrier signal not included in the transmission signal (that is,
It is possible to omit the distortion detection for the frequency at which the distortion is considered to be absent, thereby realizing efficient distortion detection.

In the amplifying device according to the present invention, as an example, the carrier signal detecting means can switch the frequency of a plurality of carrier signals, and mix the signal of the switched frequency and the output signal of the amplifier by a mixer. Then, the determination means determines whether or not the output signal of the mixer includes a carrier signal corresponding to the frequency, and detects a carrier signal included in the transmission signal based on the determination result.
That is, by sequentially switching to the frequency of a plurality of carrier signals and performing the determination processing, it is possible to detect which frequency carrier signal is included in the transmission signal. Note that it is preferable to use such a configuration of the carrier signal detecting means because, for example, the distortion detecting means having the following configuration and the carrier signal detecting means can be configured using a common mixer or the like.

That is, in the distortion detecting means provided in the amplifying device according to the present invention, as an example, the signal of the detection frequency and the output signal of the amplifier are mixed by a mixer, and the output signal of the mixer is adjacent to the detection frequency. A carrier signal having a frequency of interest is removed by a low-pass filter, and distortion of the detection frequency generated by the amplifier is detected from the output signal of the low-pass filter. Therefore, since a low-pass filter is used in particular as a filter for removing unnecessary carrier signals, as compared with a case where a similar function is realized using a band-pass filter, for example, as described in an embodiment described later, Realization is easy and realistic.

In the amplifying device according to the present invention, each of the plurality of frequencies that can be switched as the detection frequency is a frequency located at the center of a frequency interval where both carrier signals between two adjacent carrier signals do not exist. Used. Therefore, since the center frequency of the frequency interval in which neither of the two adjacent carrier signals exists is used as the detection frequency, distortion detection with the carrier signal removed is easily performed, which is preferable.

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

Further, in the present invention, for example, a base station device or a relay amplifier device having the above-described amplifier device is configured as an application object in which amplifier distortion compensation is particularly required.
Therefore, in the base station device and the relay amplification device according to the present invention,
Various effects as described above can be obtained, and accurate distortion compensation can be realized.

[0031]

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 amplifier of this embodiment. This amplifier has a configuration in which the present invention is applied to, for example, the transmission power amplifier with distortion compensation shown in FIG. Further, the transmission signal of the present example includes at least one carrier signal among a plurality of carrier signals having different frequencies, and specifically,
For example, the transmission signal may include only one carrier signal or may include two or more carrier signals depending on the communication situation.

As shown in FIG. 1, the amplifying apparatus of this embodiment includes a baseband signal generator 1 for generating a transmission signal (I component and Q component), and a vector adjuster (predistortion) for performing distortion compensation. Unit) 2, a transmission modulation unit 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 a required transmission power, and an output signal of the amplifier 4 (after amplification). A signal (not shown) such as a directional coupler that supplies a part of the signal to a mixer 7 described later and supplies the remaining part to an antenna (not shown), and is controlled by, for example, a control unit 9 described later. Multiple different carrier frequencies (local frequencies)
And a signal from the directional coupler and the like are converted to a low frequency using the signal from the synthesizer 5 (down-conversion).
And a low-pass filter (Low Pass Filter: L) that removes an unnecessary signal from the signal down-converted by the mixer 6 with predetermined filter characteristics described later.
PF) 7, an A / D converter 8 for converting an output signal of the LPF 7 into a digital signal (digital value), and a control unit 9 which is composed of, for example, a DSP and controls the distortion compensation processing performed by the vector adjustment unit 2. And a power measurement unit 10 that extracts an envelope from a transmission signal (baseband signal) input from the baseband signal generation unit 1 and detects the power of the signal.
And are provided.

The configuration and operation of the baseband signal generator 1, vector adjuster 2, transmission modulator 3, amplifier 4, directional coupler, etc., and power measuring unit 10 are shown in FIG. In the following, the synthesizer 5, the mixer 6, the LPF 7, the A / D converter 8, and the control unit 9, which constitute the feedback system of this example, are mainly described below.
Will be described in detail.

That is, in the present embodiment, the distortion (signal located in a channel adjacent to the carrier signal to be subjected to distortion compensation) generated by 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, it is a frequency located in an adjacent channel of a carrier signal to be subjected to distortion compensation.

Here, the frequency of the signal output by the synthesizer 5 of this embodiment will be described more specifically. As an example, it is assumed that a transmission signal includes a plurality of carrier signals having different frequencies, and the center frequency of a certain carrier signal is, for example, 1 as shown in FIG.
00 MHz, and the frequency of each of the other carrier signals is 5 MHz and the frequency of the adjacent carrier signal.
z (ie, the spacing between adjacent carriers is 5 MHz)
z). Further, for example, it is assumed that the waveform of each carrier signal is a W-CDMA waveform having a bandwidth of 3.84 MHz.

The synthesizer 5 of the present embodiment switches 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 detection frequency under the control of the control unit 9. It is possible and outputs a signal of the switched frequency to the mixer 6.

Specifically, for example, 100 MHz, 105
Assuming that a carrier signal having four different frequencies, such as MHz, 110 MHz, and 115 MHz, can be included in the transmission signal, the synthesizer 5 has, for example, 102.5 MHz.
z, 107.5 MHz, 112.5 MHz, 117.5
The frequency is switched to one frequency from among frequencies such as 9 MHz (97.5 MHz may be included in some cases depending on the use situation, etc.), and a signal of the frequency is output to the mixer 6.

In the above case, generally, 10
Although the frequency of the adjacent carrier leakage power for a carrier signal such as 0 MHz may be considered to be 105 MHz, 95 MHz, or the like, in this example, there is a correlation between a measurement point such as 105 MHz and a measurement point such as 102.5 MHz. Therefore, 102.5 MHz or the like is used as a main measurement point as described above.

The mixer 6 mixes a signal input from the synthesizer 5 with an output signal of the amplifier 4 input from a directional coupler or the like, thereby down-converting the output signal to a baseband band and down-converting the output signal. And a function of outputting the converted signal to the LPF 7.

FIG. 2 shows, for example, two adjacent carrier signals (a 100 MHz carrier signal and a 105 MHz carrier signal).
2 shows an example of a spectrum of a transmission signal input to the amplifier 4 when the transmission signal includes a carrier signal (Hz). Here, in this example, it is assumed that the bandwidth of each carrier signal is 3.84 MHz as described above. Also,
FIG. 3 shows an example of a spectrum of a signal (down-converted signal) output from mixer 6 to LPF 7 in such a case. The horizontal axes of the graphs shown in FIGS. 2 and 3 indicate frequency (unit is [kHz]), and the vertical axis indicates power ratio (unit is [dB]).

The LPF 7 receives the signal output from the mixer 6 and sends only the 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. here,
As a filter characteristic of the LPF 7 of this example, 105
A characteristic is set such that a carrier signal of MHz or the like (that is, a signal having a center frequency of 2.5 MHz after down-conversion) can be removed from the output signal of the mixer 6.

With such filter characteristics, L of this example is
Distortion (adjacent channel leakage power) is included in the output signal of PF7.
Frequency (ie, before being downconverted,
102.5 MHz, etc.), and only adjacent signals are not included. FIG. 4 shows an ideal setting example of the filter characteristic of the LPF 7 of this embodiment in addition to the signal spectrum shown in FIG. 3, for example. The horizontal axis of the graph shown in FIG. [KHz]), and the vertical axis indicates the power ratio (unit is [dB]).

In practice, it is sometimes difficult to realize an LPF having a steep filter characteristic as shown in FIG. 4, but for example, the filter characteristic of the LPF 7 is smaller than that shown in FIG. It may have a gentle attenuation curve shape. In short, it may be of any type as long as the above-described adjacent carrier signal can be deleted. Further, if an LPF is used as in this example, even if a single LPF cannot obtain a required attenuation curve, a plurality of LPFs are connected in series such as two or three stages. It is preferable to use it because a required attenuation curve can be easily obtained.

On the other hand, for example, a band-pass filter (Band P
(Ass Filter: BPF) can be used to limit the band. However, in general, a steep filter characteristic cannot be obtained with the BPF as shown in FIG. 4 described above. The size and cost become very large, and the feasibility of the entire device is reduced. Therefore, the use of the LPF as in this example is effective because a relatively sharp cutoff characteristic can be obtained, and is particularly effective when the interval between adjacent channels is narrow. It is valid.

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. For example, the dynamic range of the A / D converter 57 can be reduced in that the dynamic range of the A / D converter 57 can be made relatively small.

The control unit 9 detects the magnitude of a distortion (in this example, a part of the distortion) included in the output signal of the amplifier 4 based on the digital signal input from the A / D converter 8 and , The power of the transmission signal notified from the power measuring unit 10 and detects the power of the amplifier 4 based on the detection results.
Has a function of controlling the distortion compensation processing by the vector adjustment unit 2 so that the distortion included in the output signal is reduced (to approach zero). In addition, the control unit 9 of this example includes:
For example, it has a function of switching the frequency of a signal generated by the synthesizer 5 by outputting a control signal for controlling the synthesizer 5 to the synthesizer 5.

Here, as an example, the case where the amplifying device of this embodiment is used in a W-CDMA system,
An example of specific numerical values relating to the filter characteristics (pass band characteristics) of FIG. For example, in a W-CDMA system, as described above, the bandwidth of each carrier signal included in a transmission signal is 3.84 MHz, and the frequency interval between adjacent carrier signals is 5.00 MHz. Generally, the roll-off rate of the band-limiting filter is 0.22, and the cut-off frequency is 0.5.

The carrier signals included in the transmission signal are arranged so as not to overlap each other on the frequency axis. Specifically, for example, as described above, the center frequency of a certain carrier signal and the carrier signal The frequency interval between the center frequencies of adjacent carrier signals is set to 5 MHz. In this case, for example, at a frequency position 2.5 MHz away from the center frequency of a certain carrier signal, there is no component of the carrier signal and no component of a carrier signal adjacent to the carrier signal. In this case, the level of the transmission signal becomes zero.

For this reason, for example, if the magnitude of distortion at the above-mentioned frequency position separated by 2.5 MHz (2.5 MHz detuning point) is detected, accurate distortion detection can be realized. That is, when distortion occurs when the transmission signal is amplified by the amplifier 4 and the band of the output signal of the amplifier 4 is expanded as compared with the band of the transmission signal, the signal originally has a zero level as described above. Since a non-zero signal level is detected at a power detuning point of 2.5 MHz, the level can be accurately detected as a distortion level.

In order to realize the accurate distortion detection as described above, the LPF 7 converts the level of an unnecessary carrier signal having a relatively large level (the adjacent carrier signal described above) from the output signal of the mixer 6, for example. It is necessary to reduce the distortion so that a relatively small level of distortion remains in the band-limited signal.

Here, the bandwidth of each carrier signal included in the transmission signal is 3.84 MHz as described above.
For example, the required band is expanded by the band limiting characteristic given to the transmission signal by the LPF 7, and the expansion rate is determined by the roll-off rate. FIG. 5 shows an example of the band limiting characteristic of the LPF 7, which is based on the roll-off rate (= 0.22) and the cut-off frequency (= 0.22).
This corresponds to (5). Note that the horizontal axis of the graph shown in the figure is the normalized frequency (unit is [H
z]), and the vertical axis indicates a multiplication coefficient. As a specific example, the point of 1.0 on the horizontal axis corresponds to 3.84 MHz, and the point of 0.5 on the horizontal axis corresponds to 1.92 MHz.

In the band limiting characteristic shown in FIG. 5, the point at 0.6 on the horizontal axis (the normalized frequency is 2.3424 M
At the point after (point at Hz), the signal is deleted and no longer exists. FIG. 6 shows an example in which the above-mentioned band limiting characteristics are superimposed on two adjacent carrier signals. The horizontal axis of the graph shown in FIG. 6 indicates the normalized frequency based on the transmission signal band (the unit is [ Hz]), and the vertical axis indicates a multiplication coefficient.

In the band limiting characteristic shown in FIG. 6, the frequency at which the carrier signal (lower side signal) having the lower normalized frequency on the horizontal axis reaches the zero point is 2.3424 MHz, while the standardized frequency on the horizontal axis is 2.3424 MHz. The frequency at which the higher carrier signal (upper signal) reaches the zero point is 2.6576 MHz
It is preferable to detect the distortion in the frequency range between these two zero-point reaching frequencies because only the distortion can be detected with high accuracy.

That is, considering the band limiting characteristics shown in FIG. 6, the pass band width of the LPF 7 is at least 0.3152 MHz (= 2.6576 MHz−2.
3424 MHz) or less. Here, in general, the pass band width of the pass band characteristic indicates a 3 dB band width in which the power attenuation is half (ie, 3 dB). In this example, however, the pass band width is several tens dB compared to the level of the carrier signal.
In this example, the bandwidth of the cutoff frequency is indicated by the term “pass band width” because the purpose is to obtain a small distortion (adjacent channel leakage power). The attenuation curve (transfer function) of the LPF 7 may depend on the bandwidth of the distortion to be obtained, but generally does not have to be defined.

Further, in the case of the present embodiment, the center frequency does not become non-zero as shown in FIGS. 5 and 6, for example, but as shown in FIGS. 3 and 4, for example. Since the center frequency becomes zero, when the cutoff frequency bandwidth of the LPF 7 is calculated based on the above calculation, the cutoff frequency bandwidth of the LPF 7 becomes 1 of the above bandwidth.
157.6 kHz (= 0.3152 MH)
z × (１ ／)).

The amplifying device of this embodiment has a function of detecting a carrier signal included in a transmission signal (carrier sensing function) and a function of detecting distortion only at a frequency position adjacent to the frequency of the detected carrier signal. In the following, these functions will be described.

That is, generally, 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 on frequency positions adjacent to the frequencies of all carrier signals that can be included in the transmission signal. However, for example, it is useless to perform the distortion detection up to the frequency position adjacent to only the frequency of the carrier signal not included in the transmission signal (that is, the frequency position where it is considered that there is no distortion).

Therefore, the synthesizer 5 provided in the amplifying apparatus of this embodiment has not only a function of switchably generating a detection frequency for detecting distortion, for example, but also each carrier signal according to the control of the control unit 9, for example. And a function of generating a signal of the frequency in a switchable manner 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 section 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.

For example, as described in the above-mentioned problem, in general, when distortion compensation of the amplifier 4 is appropriately performed, a desired transmission signal (for example, a certain carrier signal) and unnecessary distortion (for example, a signal generated by the carrier signal) are generated. Since the level difference from the adjacent channel leakage power is about 50 dB to 60 dB, for example, when the frequency of the signal output from the synthesizer 5 is changed one after another, a signal much larger than the surrounding frequency region is obtained. When the level is detected by the control unit 9, it can be considered that the carrier signal exists at the frequency position where the signal level is detected.

Here, the effects of the carrier sense function and the like of this embodiment will be specifically described with reference to FIG. FIG. 3A shows an example of a frequency spectrum of a transmission signal when four carriers are used, that is, a transmission signal includes carrier signals having four different frequencies. In such a 4-carrier operation, for example, the carrier sense function does not have to be executed, and the distortion detection may be performed for all the detection frequency positions indicated by to in FIG.

On the other hand, FIG. 6B shows an example of the frequency spectrum of a transmission signal during two-carrier operation, that is, a carrier signal having two different frequencies exists in the transmission signal. . In such two-carrier operation (the same applies to one-carrier operation and three-carrier operation), for example, in FIG.
Performing the distortion detection for all the detection frequency positions shown in (1) and (2) is useless.

Therefore, the control unit 9 provided in the amplifying apparatus of this embodiment first switches the frequency of the signal output from the synthesizer 5 to each of the frequency positions indicated by in FIG. The level of the transmission signal at the frequency position is detected. Then, as a result of the detection, when a frequency position where the level of the transmission signal is much higher than that in the surrounding frequency region is detected, the control unit 9 determines that a carrier signal exists at the frequency position.

Thus, for example, from the next distortion detection, the frequency position adjacent to the frequency of the carrier signal existing in the transmission signal (for example, in the case shown in FIG. It suffices if distortion detection is performed only for ()). If, for example, the number or frequency position of carrier signals included in the transmission signal is changed, it is necessary to perform the same carrier signal detection processing and the like again after the change.

Next, an example of the operation performed by the amplifying device of this embodiment will be described. 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 transmission 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. Further, a part of the output signal (amplified signal) of the amplifier 4 supplied to the above-described antenna is taken out by, for example, a directional coupler or the like having a small loss for the signal radiated from the antenna and input to the mixer 6 Is done.

In the feedback system, the amplified signal input to the mixer 6 from the directional coupler or the like, and the local signal input to the mixer 6 from the synthesizer 5 (a 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 in the vicinity of the frequency of the carrier signal included in the transmission signal, and transmits the transmission amount notified from the power measurement unit 10. The power 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, when compensating for distortion generated in an amplifier that amplifies a transmission signal, using at least one carrier signal of a plurality of carrier signals having different frequencies as a transmission signal. The distortion generated in the amplifier 4 corresponding to the carrier signal of each frequency (for example, all the carrier signals included in the transmission signal) is accurately detected, and the distortion is appropriately compensated. Therefore, highly 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, only 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) is acquired,
Further, this is different from the prior art in that the LPF 7 is used to achieve this, and exhibits an excellent effect.

In a preferred embodiment of the amplifying device of this embodiment, a frequency (for example, the above-mentioned 102.5 MHz) located at the center between the center frequencies of two adjacent carrier signals is used.
z, etc.) is the local frequency for distortion detection (detection frequency)
Since the signal is output from the synthesizer 5 and used, the distortion detection with the carrier signal removed may be easily performed. Further, in the amplifying device of the present embodiment, as a preferred embodiment, for example, the bandwidth per carrier signal (for example, 3.84 MHz in this example) is set from the frequency interval between the center frequencies of adjacent carrier signals (for example, 5 MHz in this example). The LPF 7 having a narrow pass band characteristic equal to or smaller than the subtracted bandwidth is used.

Further, in the amplifying apparatus of this embodiment, the carrier signal included in the 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.

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. In this example, the frequency (detection frequency) of the signal output from the synthesizer 5 to the mixer 6 is between adjacent carrier signals (in this example, between a 100 MHz signal and a 105 MHz signal, for example). (In this example, 10 frequencies)
After mixing by the mixer 6, the LPF 7 outputs a signal adjacent to the detection frequency from the output signal of the amplifier 4 (for example, 105 MHz when the detection frequency is 102.5 MHz). ) Is removed, and the control unit 9 detects the distortion of the detection frequency (in this example, the adjacent channel leakage power) generated by the amplifier 4, thereby constituting the distortion detecting means according to the present invention. ing.

In this embodiment, the control unit 9 controls the vector adjustment unit 2 so that the distortion detected by the distortion detection unit is reduced, and the function of compensating the transmission signal before amplification by the amplifier 4 is provided. 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 the present embodiment, the distortion detecting means has a mixer 6 and an LPF 7, and detects distortion generated in the amplifier 4 from an output signal of the LPF 7. Here, the mixer 6 corresponds to a mixer according to the present invention, and for example, a detection frequency (102.5 MHz in this example) input from the synthesizer 5.
z) and the output signal of the amplifier 4 are mixed. The LPF 7 corresponds to a low-pass filter according to the present invention, and removes a carrier signal having a frequency adjacent to the detection frequency (105 MHz in this example) from the output signal of the mixer 6.

In this embodiment, as a preferable mode, the frequency for detection is, as described above, the frequency of the carrier signal to be subjected to distortion compensation (100 MHz in this embodiment).
) And a frequency of a carrier signal adjacent to the carrier signal (in this example, 105 MHz or the like) is located at the center of a frequency interval where both carrier signals do not exist (in this example, 102.5 MHz or the like). Is used. The frequency interval where both carrier signals do not exist is an interval between frequency portions where neither component of the both carrier signals exists. In this example, for example, 101.92 (= 100 +
(3.82 / 2)) MHz and 103.08 (= 105−
(3.84 / 2)) It is an interval such as between MHz.

In this example, the control section 9 controls the synthesizer 5 to control the carrier signal (whichever is included in the transmission signal) based on the digital signal input through the mixer 6, the LPF 7, and the A / D converter 8. The function of detecting whether or not the carrier signal is included in the transmission signal) constitutes the carrier signal detecting means according to the present invention. In this example,
The distortion detecting means is configured to detect a frequency of a carrier signal detected by the carrier signal detecting means (for example, 1 in this example).
00 MHz or the like (in this example, for example, 1
02.5 MHz) is switched as the detection frequency.

In this embodiment, the carrier signal detecting means has a mixer 6, a control unit 9, and the like.
A carrier signal included in the transmission signal is detected. That is, the mixer 6 corresponds to the mixer according to the present invention, and for example, mixes a signal (hereinafter, referred to as a signal A) input from the synthesizer 5 capable of switching the frequency of a plurality of carrier signals with an output signal of the amplifier 4. I do. In this example, the control unit 9 constituting the determination means according to the present invention inputs the output signal of the mixer 6 via the LPF 7 and the A / D converter 8 and the output signal corresponds to the frequency of the signal A. It is determined whether or not a carrier signal to be included is included, and a carrier signal included in the transmission signal is detected based on the determination result.

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, a base station apparatus according to a second 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. 8 shows an example of the appearance of a casing constituting the base station apparatus of the present embodiment. As shown in FIG. 8, 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 is installed in the lower part of the section.

FIG. 9 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, and an amplifier having a distortion compensation function similar to that of the amplifying apparatus shown in the first embodiment and transmitting a transmission signal by an amplifier. A transmission power amplifying unit 24 for amplifying, and an antenna unit 25 for transmitting and receiving a radio signal using an antenna 26 described later
Also, a control unit 27 for controlling the antenna 26 and various processes performed by the processing units 21 to 26 is provided.

Here, in this example, for example, the interface unit 21, the baseband signal processing unit 22, the radio transmitting / receiving unit 2
The MDE unit shown in FIG. 8 is configured by the control unit 3 and the control unit 27. For example, the amplifier unit illustrated in FIG. 8 is configured by the transmission power amplifying unit 24.

Next, an example of the 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 the wired transmission path, and then performs the radio transmission / reception unit 2.
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 the antenna unit 25 via the antenna 26, and the received signal is received by the wireless transmitting / receiving unit 23, and then the 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 embodiment is provided with a distortion compensation function similar to that of the amplifying apparatus shown in the first embodiment, for example, to compensate for the distortion generated in the amplifier. As in the case of the first embodiment, the distortion generated in the amplifier corresponding to the carrier signal of each frequency included in the transmission signal is accurately detected, and appropriate distortion compensation is performed on the distortion. Therefore, it is possible to realize a highly accurate distortion compensation process.

Further, as in the case of the first embodiment, the base station apparatus of the present embodiment can realize a great reduction in power consumption and a reduction in required cost. As a result, it is possible to reduce the price and the size of the apparatus. 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 employing the CDMA system has been described. However, the present invention is applied to a base station apparatus employing another communication system such as the TDMA system or the FDMA system. It is also possible to apply

Further, in the base station apparatus of the present embodiment, 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. 10 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, f
After individually amplifying the two signals for each frequency,
A method of combining amplified signals of the respective frequencies f1 and f2 is used. Specifically, the signal of the frequency f1 is
While the signal of the other frequency f2 is amplified by another amplifier 32, and these two amplified signals are combined by a 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. 11 shows a configuration example of an amplifier section using a common amplifier (an amplifier section for performing common amplification). In this amplifier section, 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. 11, the signal obtained by combining the signals of two different frequencies f1 and f2 is equally distributed by the distributor 41 (not the distribution for each frequency, but the distribution of the power, for example). ), And after the respective divided signals are amplified by the respective common amplifiers 42 and 43, the combiner 44
Are synthesized by 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 combining, the same signal is combined, so that no combining loss occurs unlike the amplifier unit 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 only necessary to amplify and output [W], and the amplifier efficiency is better than that of the amplifier section shown in FIG.

Although the intermodulation distortion is generated in the amplifier section shown in FIG. 11, 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 configuration of the amplifying device according to the present invention and the configuration of the base station device according to the present invention are not necessarily limited to those shown in the first and second embodiments, but may be various. Any configuration may be used. As an example, the application field of the amplifying device according to the present invention is not necessarily limited to the base station device. The amplifying device according to the present invention is, for example, a mobile station device (for example, a mobile phone device) that needs to compensate for distortion generated in an amplifier. The present invention can be applied to various devices such as a telephone terminal device and a PHS terminal device and a relay amplifier 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. In addition, the present invention can be understood as a computer-readable recording medium such as a floppy disk or a CD-ROM storing the above-mentioned control program. Thereby, the processing according to the present invention can be performed.

[0098]

As described above, in the amplifying apparatus, the base station apparatus and the relay amplifying apparatus according to the present invention, at least one carrier signal of a plurality of carrier signals having different frequencies is used as a transmission signal. Is amplified by an amplifier, a plurality of frequencies located between respective adjacent carrier signals are switched as detection frequencies, a carrier signal having a frequency adjacent to the switched detection frequency is removed from an output signal of the amplifier, and Since the generated distortion of the detection frequency is detected and the transmission signal before amplification by the amplifier or the output signal of the amplifier is distortion-compensated so that the detected distortion is reduced, for example, the distortion included in the output signal is included. Of the carrier signal included in the output signal (the carrier signal having a frequency adjacent to the detection frequency). Signal), it is possible to accurately detect the distortion corresponding to each carrier signal (each detection frequency), thereby improving the accuracy of distortion compensation. Can be done.

In the amplifier, the base station, and the relay amplifier according to the present invention, as a preferable mode, the distortion is detected by using a low-pass filter. Specifically, the signal of the detection frequency and the output of the amplifier are output. The signal is mixed by a mixer, a carrier signal having a frequency adjacent to the detection frequency is removed from the output signal of the mixer by a low-pass filter, and the distortion of the detection frequency generated by the amplifier is detected from the output signal of the low-pass filter. I did it.

In a preferred embodiment of the amplifying apparatus, the base station apparatus, and the relay amplifying apparatus according to the present invention, as a plurality of frequencies that can be switched as detection frequencies,
Since the frequency located at the center of the frequency interval in which both carrier signals between two adjacent carrier signals are absent is used, distortion detection with the carrier signal removed becomes easy to perform.

In the amplifying apparatus, base station apparatus and relay amplifying apparatus according to the present invention, a carrier signal included in a transmission signal is detected, and only a frequency adjacent to the frequency of the detected carrier signal is switched as a detection frequency. For this reason, for example, it is possible to omit the distortion detection for the frequency adjacent to the frequency of the carrier signal not included in the transmission signal (that is, the frequency where it is considered that there is no distortion). Can be realized.

In the amplifying device, the base station device, and the relay amplifying device according to the present invention, for example, a mixer used for distortion detection is shared, and a signal having a frequency corresponding to a carrier signal to be determined and an amplifier are used. The output signal is mixed with a mixer, it is determined whether or not the output signal of the mixer includes the carrier signal to be determined, and the carrier signal included in the transmission signal is detected based on the determination result. . In the amplifying apparatus, the base station apparatus, and the relay amplifying apparatus according to the present invention, as a preferred embodiment, a common amplifier is used as an amplifier, so that efficient amplifying processing can be realized.

[Brief description of the drawings]

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

FIG. 2 is a diagram illustrating an example of a spectrum of a transmission signal input to an amplifier when two adjacent carrier signals are included in the transmission signal.

FIG. 3 is a diagram illustrating an example of a spectrum of a signal output from a mixer to an LPF.

FIG. 4 is a diagram showing an ideal setting example of a filter characteristic of an LPF.

FIG. 5 is a diagram illustrating an example of a band limiting characteristic of an LPF.

FIG. 6 is a diagram illustrating an example in which LPF band limiting characteristics are superimposed on two adjacent carrier signals.

FIG. 7 is a diagram illustrating an example of a frequency spectrum of a transmission signal during 4-carrier operation and 2-carrier operation.

FIG. 8 is a diagram illustrating an example of an external appearance of a housing forming a base station device according to a second embodiment of the present invention.

FIG. 9 is a diagram illustrating a schematic configuration example of a base station apparatus according to a second embodiment of the present invention.

FIG. 10 is a diagram illustrating a configuration example of an amplifier unit that performs individual amplification.

FIG. 11 is a diagram illustrating a configuration example of an amplifier unit that performs common amplification.

FIG. 12 is a diagram illustrating an example of a spectrum of a transmission signal before being input to an amplifier.

FIG. 13 is a diagram illustrating an example of a spectrum of a signal output when a transmission signal is amplified by an amplifier when distortion compensation is not performed.

FIG. 14 is a diagram illustrating a configuration example of a transmission power amplifier with distortion compensation according to a conventional example.

FIG. 15 is a diagram illustrating an example of a spectrum of a signal that is output after a transmission signal is amplified by an amplifier when distortion compensation is performed.

[Explanation of symbols]

1. baseband signal generation unit, 2. vector adjustment unit, 3. transmission modulation unit, 4, 31, 32,.
5 ・ ・ Synthesizer 、 6 ・ Mixer 、 7 ・ ・ LP
F, 8 ··· A / D converter, 9 ··· control unit, 10 ···
Power measurement unit, 21. Interface unit, 22. Baseband signal processing unit, 23. Wireless transmission / reception unit, 24
..Transmission power amplification section, 25. Antenna section, 26.
.Antennas, 33, 44..combiners, 41..dividers, 42,43..common amplifiers

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5K022 EE02 EE21 5K060 BB05 DD04 FF00 HH11 HH16 HH32 KK06 5K067 AA03 BB04 CC10 EE10 KK13

Claims (8)

[Claims] An amplifier for amplifying a transmission signal, wherein the amplifier amplifies the transmission signal using at least one of a plurality of carrier signals having different frequencies as a transmission signal. And a plurality of frequencies located between adjacent carrier signals can be switched as a detection frequency, and a carrier signal having a frequency adjacent to the switched detection frequency is removed from an output signal of the amplifier and generated by the amplifier. Distortion detecting means for detecting the distortion of the detection frequency, and distortion compensating means for distortion-compensating the transmission signal or the output signal of the amplifier before amplification by the amplifier so that the distortion detected by the distortion detecting means is reduced. An amplification device, comprising: 2. The amplifying device according to claim 1, further comprising: a carrier signal detecting unit configured to detect a carrier signal included in the transmission signal, wherein the distortion detecting unit detects a frequency of the carrier signal detected by the carrier signal detecting unit. An amplifying device characterized in that only an adjacent frequency is switched as a detection frequency. 3. The amplifying device according to claim 2, wherein the carrier signal detecting means is capable of switching frequencies of the plurality of carrier signals, and mixing a signal of the switched frequency and an output signal of the amplifier. Determining means for determining whether the output signal of the mixer includes a carrier signal corresponding to the frequency, and detecting a carrier signal included in the transmission signal based on the determination result. apparatus. 4. The amplifying device according to claim 1, wherein the distortion detecting means comprises: a mixer for mixing a signal having a frequency for detection and an output signal of the amplifier; and an output signal of the mixer. And a low-pass filter for removing a carrier signal having a frequency adjacent to the detection frequency from the detection signal, and detecting distortion of the detection frequency generated in the amplifier from an output signal of the low-pass filter. 5. The amplifying device according to claim 1, wherein each of the plurality of frequencies switched as the detection frequency has no carrier signal between two adjacent carrier signals. An amplification device having a frequency located at the center of a suitable frequency interval. 6. The amplifying device according to claim 1, wherein the amplifier is a common amplifier capable of amplifying a plurality of carrier signals having different frequencies collectively. Amplifying device. 7. A base station device comprising the amplifying device according to claim 1. Description: 8. A relay amplifying device comprising the amplifying device according to claim 1. Description: