WO2002078181A1

WO2002078181A1 - High frequency amplifier

Info

Publication number: WO2002078181A1
Application number: PCT/JP2001/004287
Authority: WO
Inventors: Kenichi Horiguchi; Masatoshi Nakayama; Yukio Ikeda; Osami Ishida; Yuuji Sakai; Kazuyuki Totani
Original assignee: Mitsubishi Denki Kabushiki Kaisha
Priority date: 2001-03-23
Filing date: 2001-05-22
Publication date: 2002-10-03
Also published as: KR100522068B1; JP3923270B2; JP2002290163A; CN1430809A; KR20030014237A; CN1183663C

Abstract

A high frequency amplifier comprising an amplifier (1) for amplifying an input signal, an input signal discriminating circuit (6) for issuing instructions to detect the peak and average powers of the input signal to calculate the peak-average power ratio, to make a comparison between the calculated peak-average power ratio and a predetermined reference value, and to control a gate voltage to be fed to the amplifier (1) on the basis of the result of the comparison, and a gate voltage control circuit (7) for controlling a gate voltage to be fed to the amplifier (1) on the basis of instructions from the input signal discriminating circuit (6) in such a manner that even if the peak-average power ratio of the input signal varies, the distortion power fed from the amplifier (1) does not vary.

Description

Description High-frequency amplifier Technical field

The present invention relates to a high-frequency amplifier for amplifying a high-frequency signal. Background art

FIG. 1 is a block diagram showing the configuration of a conventional high-frequency amplifier disclosed in the literature, Stephen A. Maas, "Nonlinear Microwave Circuits," Artech House, 1988, where 1 denotes a high-frequency input. An amplifier for amplifying the signal, 2 is a power supply circuit for supplying a gate voltage Vg and a drain voltage Vd to the amplifier 1, 3 is an input terminal, and 4 is an output terminal.

Next, the operation will be described.

FIG. 2 is a diagram showing a temporal change of input power in an input signal. As shown in FIG. 2, the input signal input to the input terminal 3 has an input signal M having a peak input power P peak 1 in a certain time zone T 1 with respect to the average input power P ave. In another time zone T2, it is assumed that the input signal N of the input power Ppeak2 is input. Assuming that the ratio of the peak output power P peak to the average input power P ave of peak P Peak / P av is the peak-average power ratio Pr, the beak-average power ratio Pr changes with the input signals M and N. I do.

FIG. 3 is a diagram showing an average output power characteristic and a distortion power characteristic with respect to an average input power of a conventional high-frequency amplifier. In the figure, 101 is the average power characteristic, 210 is the distortion power characteristic when the input signal M is input to the amplifier 1, and 202 is the distortion power characteristic when the input signal N is input to the amplifier 1. And the power times It is assumed that the gate voltage V gl and the drain voltage V dl are supplied to the amplifier 1 from the path 2.

As shown in Fig. 3, the distortion power when the average output power P1 is output from the amplifier 1 is D1 when the input signal M is input to the amplifier 1, and the input signal N is input when the input signal N is input to the amplifier 1. Is D2. That is, when the input signal changes from the input signal M to the input signal N, the peak-average power ratio Pr increases, and the distortion power increases from D1 to D2.

Since the conventional high-frequency amplifier is configured as described above, if the input signal changes and the peak-to-average power ratio Pr changes when amplifier 1 outputs the average output power P a V e, When the power changes and the input signal N having a large peak-to-average power ratio p _r is input to the amplifier 1, the distortion power increases.

The present invention has been made to solve the above problems, and has as its object to obtain a high-frequency amplifier capable of suppressing a change in output distortion power even when the peak-to-average power ratio Pr changes. And Disclosure of the invention

The high-frequency amplifier according to the present invention includes an amplifier that amplifies an input signal, a peak-average power ratio detected by detecting a peak power and an average power of the input signal, and a calculated peak-average power ratio and a predetermined reference value. An input signal discriminating circuit for instructing to control the gate voltage or the drain voltage supplied to the amplifier based on the comparison result, and a peak signal of the input signal based on an instruction from the input signal discriminating circuit. A voltage control circuit that controls a gate voltage or a drain voltage supplied to the amplifier so that the distortion power output from the amplifier does not change even if the average power ratio changes. As a result, even if the peak-to-average power ratio of the input signal changes, there is an effect that a change in distortion power output from the amplifier can be suppressed.

In the high-frequency amplifier according to the present invention, the input signal discriminating circuit includes an average power detecting circuit that detects an average power of the input signal, a peak power detecting circuit that detects a beak power of the input signal, and the average power detecting circuit. A power ratio calculating circuit that calculates a peak-to-average power ratio based on the average power of the input signal detected by the above and the peak power detection circuit, based on the beak power of the input signal detected by the peak power detecting circuit; The peak-to-average power ratio calculated by the circuit is compared with a predetermined reference value, and based on the comparison result, the voltage control circuit controls the gate voltage or the drain voltage supplied to the amplifier. And a comparison circuit for instructing.

As a result, even if the peak-to-average power ratio of the input signal changes, there is an effect that the change in the distortion power output from the amplifier can be suppressed.

In the high-frequency amplifier according to the present invention, when the peak-to-average power ratio calculated by the input signal discriminating circuit is higher than a predetermined reference value, the peak-to-average power ratio is set to a predetermined value. The gate voltage supplied to the amplifier is increased as compared with the case where the reference voltage is lower than the reference value.

In the high frequency amplifier according to the present invention, when the voltage control circuit has a peak-to-average power ratio that is higher than a predetermined reference value, the peak-to-average power ratio is higher than the predetermined reference value. The drain voltage supplied to the amplifier is increased as compared with the case where the voltage is lower.

A high-frequency amplifier according to the present invention includes: an amplifier for amplifying an input signal; Detect the peak power and average power of the signal to calculate the peak-to-average power ratio, compare the calculated peak-to-average power ratio with a predetermined reference value, and based on the comparison result, the gate to be supplied to the amplifier. Input signal discriminating circuit that instructs to control the voltage and drain voltage, and distortion power output from the amplifier even if the peak-to-average power ratio of the input signal changes based on the instruction from the input signal discriminating circuit. And a voltage control circuit for controlling a gate voltage and a drain voltage supplied to the amplifier so that the voltage does not change.

In the high frequency amplifier according to the present invention, the input signal discriminating circuit includes an average power detecting circuit for detecting an average power of the input signal, a beak power detecting circuit for detecting a beak power of the input signal, and the average power detecting circuit. A power ratio calculating circuit for calculating a peak-to-average power ratio based on the average power of the input signal detected by the input signal and the peak power of the input signal detected by the peak power detecting circuit; The peak-average power ratio calculated by the circuit is compared with a predetermined reference value, and the voltage control circuit is instructed to control the gate voltage and the drain voltage supplied to the amplifier based on the comparison result. And a comparison circuit.

In the high-frequency amplifier according to the present invention, when the voltage-control circuit has a peak-average power ratio calculated by the input signal determination circuit that is higher than a predetermined reference value, the peak-average power ratio is set to a predetermined reference value. Compared to a lower case, the gate voltage supplied to the amplifier is increased, and the drain voltage supplied to the amplifier is increased. As a result, even if the peak-to-average power ratio of the input signal changes, there is an effect that the change in the distortion power output from the amplifier can be suppressed.

In the high frequency amplifier according to the present invention, when the voltage control circuit has a peak-to-average power ratio that is higher than a predetermined reference value, the peak-to-average power ratio is higher than the predetermined reference value. As compared with a lower case, the gate voltage supplied to the amplifier is increased, and the drain voltage supplied to the amplifier is reduced.

As a result, even if the peak-to-average power ratio of the input signal changes, it is possible to suppress the change in the distortion power output from the amplifier.

In the high frequency amplifier according to the present invention, when the voltage control circuit determines that the peak-to-average power ratio is higher than the predetermined reference value, the peak-to-average power ratio is higher than the predetermined reference value. In this case, the gate voltage supplied to the amplifier is reduced and the drain voltage supplied to the amplifier is increased, as compared with the case where the voltage is lower.

A high-frequency amplifier according to the present invention includes: an amplifier that amplifies an input signal; and external instruction information such as a type of an input signal input to the amplifier and a magnitude of an average output power output from the amplifier. The gate voltage or drain voltage supplied to the amplifier, or the gate and drain voltages supplied to the amplifier, so that the distortion power output from the amplifier does not change even if the content of the external instruction information changes. This has a voltage control circuit for controlling. Thus, even if the content of the external instruction information changes, it is possible to suppress a change in the distortion power output from the amplifier. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a block diagram showing a configuration of a conventional high-frequency amplifier.

FIG. 2 is a diagram showing a temporal change of input power in an input signal of a conventional high-frequency amplifier.

FIG. 3 is a diagram showing an average output power characteristic and a distortion power characteristic with respect to an average input power of a conventional high-frequency amplifier.

FIG. 4 is a block diagram showing a configuration of the high-frequency amplifier according to Embodiment 1 of the present invention.

FIG. 5 is a diagram showing an average output power characteristic and a distortion power characteristic with respect to an average input power of the high-frequency amplifier according to Embodiment 1 of the present invention.

FIG. 6 is a block diagram showing a configuration of a high-frequency amplifier according to Embodiment 2 of the present invention.

FIG. 7 is a diagram showing an average output power characteristic and a distortion power characteristic with respect to an average input power of the high-frequency amplifier according to Embodiment 2 of the present invention.

FIG. 8 is a block diagram showing a configuration of a high-frequency amplifier according to Embodiment 3 of the present invention.

FIG. 9 is a diagram showing average output power characteristics and distortion power characteristics with respect to average input power of the high-frequency amplifier according to Embodiment 3 of the present invention.

FIG. 10 is a diagram showing another average output power characteristic with respect to the average input power of the high-frequency amplifier according to Embodiment 3 of the present invention.

FIG. 11 is a block diagram showing a configuration of a high-frequency amplifier according to Embodiment 4 of the present invention.

FIG. 12 is a block diagram showing a configuration of a high-frequency amplifier according to Embodiment 4 of the present invention.

FIG. 13 is a block diagram showing a configuration of a high-frequency amplifier according to Embodiment 4 of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, in order to explain this invention in greater detail, the preferred embodiments of the present invention will be described with reference to the accompanying drawings.

Embodiment 1.

FIG. 4 is a block diagram showing a configuration of the high-frequency amplifier according to Embodiment 1 of the present invention. In the figure, 5 is a directional coupler that extracts a part of the input signal, 6 is the peak power P peak and the average power P ave of the input signal extracted from the directional coupler 5, and the peak and average power is detected. Calculates the ratio Pr, compares the calculated peak-to-average power ratio Pr with a predetermined reference value Ps, and, based on the result of the comparison, instructs to control the gate voltage Vg supplied to the amplifier 1. A signal determination circuit 7 is a gate voltage control circuit (voltage control circuit) that controls a gate voltage Vg supplied from the power supply circuit 2 to the amplifier 1 based on an instruction of the input signal determination circuit 6.

In the input signal discriminating circuit 6 shown in FIG. 4, 11 is an average power detecting circuit for detecting the average power P a V e of the input signal extracted from the directional coupler 5, and 12 is the directional coupler 5. The peak power detection circuit 13 detects the peak power P peak of the input signal extracted from the input signal, and 13 denotes the average power P a V e of the input signal detected by the average power detection circuit 11, and the peak power detection circuit 12 A power ratio calculation circuit that calculates the peak-to-average power ratio Pr (= P peak / P ave) based on the detected peak power P peak of the input signal, and 14 is calculated by the power ratio calculation circuit 13 The peak-to-average power ratio Pr is compared with a predetermined reference value Ps, and the gate voltage Vg supplied to the amplifier 1 is supplied to the gate voltage control circuit 7 based on the comparison result. This is a comparison circuit that instructs to control.

In Fig. 4, other configurations are the same as the conventional configuration in Fig. 1. is there.

Next, the operation will be described.

Input signals M and N as shown in FIG. 2 are input from the input terminal 3, input to the amplifier 1 via the directional coupler 5, and the amplified signal is output from the output terminal 4. The drain voltage Vd (= Vd 1) is directly supplied from the power supply circuit 2 to the amplifier 1. In addition, two kinds of gate voltages Vg (two Vgl or Vg2) are supplied from the power supply circuit 2 to the amplifier 1 through the gate voltage control circuit 7, but the amplifier 1 uses the gate voltage Vgl. Is supplied, amplification is performed by Class B operation to increase power supply efficiency, and when the gate voltage Vg2 is supplied, amplification by Class A operation is performed to improve distortion. ing.

The input signal extracted from the directional coupler 5 is input to the input signal discrimination circuit 6. In the input signal discriminating circuit 6, the average power detecting circuit 11 detects the average power P ave of the input signal, and the peak power detecting circuit 12 detects the peak power P peak of the input signal. The power ratio calculation circuit 13 is based on the average power P ave of the input signal detected by the average power detection circuit 11 and the beak power P peak of the input signal detected by the peak power detection circuit 12. Then, calculate the peak-to-average power ratio Pr (= P peak / P ave).

The comparison circuit 14 compares the peak-to-average power ratio Pr calculated by the power ratio calculation circuit 13 with a predetermined reference value Ps. For example, when the input signal M is input to the input terminal 3, If the peak-to-average power ratio Pr is smaller than the predetermined reference value Ps, the gate voltage control circuit 7 is instructed to supply the amplifier 1 with the predetermined gate voltage Vg1. When the input signal N is input to the input terminal 3 and the peak-to-average power ratio Pr is larger than a predetermined reference value Ps, the amplifier 1 is separated from the gate voltage control circuit 7 by the amplifier 1. To supply the predetermined gate voltage Vg2 of the above.

The gate voltage control circuit 7 supplies the gate voltage V g1 or V g 2 to the amplifier 1 based on the instruction from the comparison circuit 14. When the gate voltage V g 1 is supplied, the amplifier 1 performs amplification processing by class B operation to increase power supply efficiency, and when the gate voltage V g 2 is supplied, the amplifier A class A to improve distortion. Performs amplification by operation.

FIG. 5 is a diagram showing an average output power characteristic and a distortion power characteristic with respect to an average input power of the high-frequency amplifier according to Embodiment 1 of the present invention. In FIG. 5, reference numeral 101 denotes an input signal M input and a gate voltage V Average output power characteristics at gl, 201: Distortion power characteristics when input signal M is input to amplifier 1 and gate voltage Vgl, 202: Gate when input signal N is input to amplifier 1 This is the distortion power characteristic when the voltage is Vgl, and the average output power characteristic 101 and the distortion power characteristics 201 and 202 are the same as those in FIG.

In FIG. 5, 102 is the average output power characteristic when the input signal N is input and the gate voltage is Vg2, and 203 is the average output power characteristic when the input signal N is input to the amplifier 1 and the gate voltage Vg2. It is assumed that the drain voltage Vdl is supplied from the power supply circuit 2 to the amplifier 1.

As shown in FIG. 5, when the input signal M is input, the beak 'average power ratio Pr is smaller than the predetermined reference value Ps, and the gate voltage Vg1 is supplied to the amplifier 1, The average output power characteristic is 101, the distortion power characteristic is 201, and the distortion power when the average output power is P1 is D1. On the other hand, when the input signal N is input, the peak-to-average power ratio Pr is larger than the predetermined reference value Ps, and the gate voltage Vg2 is supplied to the amplifier 1, the average output power characteristic becomes In 102, the distortion power characteristic is 203, and the distortion power when the average output power is P1 is D1 as in the case where the input signal M is input. That is, the distortion power D when the gate voltage V 1 The distortion power is improved to D 1 from 2.

The gate voltage control circuit 7 has a gate voltage V gl for obtaining an average output power characteristic 101 and a distortion power characteristic 210 for an input signal M, and an average output power characteristic for an input signal N. The gate voltage Vg2 is set in advance so as to obtain the power characteristic 102 and the distortion power characteristic 203, and the gate voltage control circuit 7 is set based on the instruction from the comparison circuit 14. The selected gate voltage V g1 or V g2 is supplied to the amplifier 1.

To obtain the average output power characteristic 102 from the average output power characteristic 101, increase the gate voltage V gl when obtaining the average output power characteristic 101 and increase the gate voltage V gl g 2, that is, the drain current of the amplifier 1 is increased, and the gain may be changed in a direction to increase the gain of the amplifier 1. Further, in order to obtain the distortion power characteristic 203 with respect to the distortion power characteristic 202, the gate voltage V gl when obtaining the distortion power characteristic 202 is increased to be the gate voltage V g2. That is, the amplifier 1 may be changed from the amplification processing of the class B operation to the amplification processing of the class A operation, and the amplifier 1 performs the amplification processing of the class A operation, so that the distortion power characteristic 200 3 As described above, the distortion power is improved. As described above, according to the first embodiment, even if the peak-to-average power ratio Pr of the input signal changes, the gate voltage Vg supplied to the amplifier 1 is controlled. Thus, the effect that the change in the distortion power output from the amplifier 1 can be suppressed is obtained. Embodiment 2

FIG. 6 is a block diagram showing a configuration of a high-frequency amplifier according to Embodiment 2 of the present invention. In the drawing, reference numeral 8 denotes a power supply circuit 2 that supplies power to amplifier 1 based on an instruction from input signal discrimination circuit 6. The drain voltage control circuit (voltage control circuit) controls the drain voltage Vd. Other configurations are embodiments This is equivalent to the configuration in FIG. The configuration of the input signal discrimination circuit 6 is the same as the configuration of FIG. 4 in the first embodiment, but the input signal discrimination circuit 6 has a peak-to-average power ratio Pr and a predetermined reference value Ps. And instructs the drain voltage control circuit 8 to control the drain voltage Vd supplied to the amplifier 1 based on the comparison result.

Next, the operation will be described.

Input signals M and N as shown in FIG. 2 are input from input terminal 3, input to amplifier 1 via directional coupler 5, and the amplified signal is output from output terminal 4. Gate voltage V g (= V g 1) is directly supplied from power supply circuit 2 to amplifier 1. Further, two types of drain voltages V d (= V dl or V d 2) are supplied from the power supply circuit 2 to the amplifier 1 via the drain voltage control circuit 8, but the amplifier 1 When the drain voltage Vd2 is supplied, the saturation power is set to be higher than when the drain voltage Vd1 is supplied.

The input signal extracted from the directional coupler 5 is input to the input signal discriminating circuit 6 and processed in the same manner as in the first embodiment. That is, the average power detection circuit 11 detects the average power P a Ve of the input signal, the peak power detection circuit 12 detects the peak power P peak of the input signal, and the power ratio calculation circuit 13 detects the peak power P peak. · Calculate the average power ratio Pr.

The comparison circuit 14 compares the calculated peak-to-average power ratio Pr with a predetermined reference value Ps.For example, when the input signal M is input to the input terminal 3, the peak-to-average power ratio pr is determined. If it is smaller than the reference value P s, the drain voltage control circuit 8 is instructed to supply a predetermined drain voltage Vd 1 to the amplifier 1. When the input signal N is input to the input terminal 3 and the peak-to-average power ratio pr is larger than a predetermined reference value Ps, another predetermined voltage is supplied to the drain voltage control circuit 8 to the amplifier 1. Drain power Instruct to supply pressure Vd2.

The drain voltage control circuit 8 supplies the drain voltage Vd1 or Vd2 to the amplifier 1 based on the instruction from the comparison circuit 14. When the drain voltage Vd2 is supplied to the amplifier 1, the saturation power increases when the drain voltage Vd1 is supplied.

FIG. 7 is a diagram showing an average output power characteristic and a distortion power characteristic with respect to an average input power of the high-frequency amplifier according to the second embodiment of the present invention. In the figure, 101 denotes an input signal M input and a drain voltage V Average output power characteristic at dl, 210 is distortion power characteristic at the time when the input signal M is input to the amplifier 1 and the drain voltage is Vd1, and 220 is the input signal N when the input signal N is input to the amplifier 1. The average output power characteristic 101 and the distortion power characteristics 201 and 202 are the same as those in FIG. 5 of the first embodiment.

In FIG. 7, 103 is the average output power characteristic when the input signal N is input and the drain voltage is Vd2, and 204 is the average output power characteristic when the input signal N is input to the amplifier 1 and the drain voltage is This is the distortion power characteristic at V d 2, and it is assumed that the gate voltage V g 1 is supplied from the power supply circuit 2 to the amplifier 1.

As shown in Fig. 7, when the input signal M is input, the peak-to-average power ratio Pr is smaller than the predetermined reference value Ps, and the drain voltage Vd1 is supplied to the amplifier 1. , The average output power characteristic is 101, the distortion power characteristic is 201, and the distortion power when the average output power is P 1 is D 1 ο

On the other hand, when the input signal N is input, the peak-to-average power ratio Pr is larger than the predetermined reference value Ps, and the drain voltage Vd2 is supplied to the amplifier 1, the average output power The characteristic is 103, the distortion power characteristic is 204, and the average output power is P1. As in the case, it becomes D l. That is, the distortion power D 2 is improved from the distortion power D 2 at the drain voltage V dl to the distortion power D 1.

The drain voltage control circuit 8 has a drain voltage V d 1 for obtaining an average output power characteristic 101 and a distortion power characteristic 201 for an input signal M, and a drain voltage V d 1 for an input signal N. The drain voltage Vd2 is set in advance so that the average output power characteristic 103 and the distortion power characteristic 204 can be obtained, and the drain voltage control circuit 8 operates based on the instruction from the comparison circuit 14. Then, the set drain voltage Vd1 or Vd2 is selected and supplied to the amplifier 1.

In order to obtain the average output power characteristic 103 with respect to the average output power characteristic 101, the drain voltage Vd1 when obtaining the average output power characteristic 101 is increased by increasing the drain voltage Vd1. d 2, that is, the direction in which the saturation power of the amplifier 1 increases. Also, in order to obtain the strain power characteristic 204 with respect to the strain power characteristic 202, the drain voltage Vd1 when the distortion power characteristic 202 is obtained is increased to increase the drain voltage. V d 2, that is, the direction in which the saturation power of the amplifier 1 increases may be changed. When the saturation power of the amplifier 1 increases, the output back-off (the ratio of the saturation power to the output power) of the amplifier 1 increases. Thus, the distortion power is improved as in the distortion power characteristic 204. As described above, according to the second embodiment, even if the peak-to-average power ratio Pr of the input signal changes, by controlling the drain voltage V d supplied to the amplifier 1, The effect is obtained that the change in the output distortion power can be suppressed. Embodiment 3.

FIG. 8 is a block diagram showing a configuration of a high-frequency amplifier according to Embodiment 3 of the present invention. Embodiment 3 is a combination of Embodiments 1 and 2, and has a gate voltage control. Circuit 7 (voltage control circuit) and drain It has an in-voltage control circuit 8 (voltage control circuit). That is, the input signal discrimination circuit 6 compares the peak-average power ratio Pr with a predetermined reference value Ps, and based on the comparison result, provides the gate voltage control circuit 7 and the drain voltage control circuit 8 with: Instructs to control the gate voltage Vg and the drain voltage Vd supplied to the amplifier 1.

Next, the operation will be described.

Input signals M and N as shown in FIG. 2 are input from input terminal 3, input to amplifier 1 via directional coupler 5, and the amplified signal is output from output terminal 4. Two kinds of gate voltages V g (= V gl or V g 2) are supplied from the power supply circuit 2 to the amplifier 1 through the gate voltage control circuit 7 and two kinds of drain voltages V d ( = V dl or V d 2) is supplied through the drain voltage control circuit 8.

When the gate voltage V g1 is supplied, the amplifier 1 performs amplification processing by class B operation to increase power supply efficiency, and when the gate voltage V g2 is supplied, the amplifier 1 performs A amplification to improve distortion. When the drain voltage V d2 is supplied, the saturation power is set to be higher than when the drain voltage V d1 is supplied.

The input signal extracted from the directional coupler 5 is input to the input signal discriminating circuit 6 and processed in the same manner as in the first embodiment. That is, the average power detection circuit 11 detects the average power PaVe of the input signal, the beak power detection circuit 12 detects the peak power Ppeak of the input signal, and the power ratio calculation circuit 13 detects the peak power Ppeak. · Calculate the average power ratio Pr.

The comparison circuit 14 compares the calculated peak-to-average power ratio Pr with a predetermined reference value Ps.For example, when the input signal M is input to the input terminal 3 and the peak-to-average power ratio pr is If it is smaller than the reference value P s, a predetermined gate voltage V g 1 is supplied to the amplifier 1 by the gate voltage control circuit 7. The drain voltage control circuit 8 is instructed to supply a predetermined drain voltage V d1 to the amplifier 1. When the input signal N is input to the input terminal 3 and the peak-to-average power ratio Pr is larger than a predetermined reference value Ps, another predetermined gate is supplied to the amplifier 1 with respect to the gate voltage control circuit 7. The voltage Vg2 instructs the drain voltage control circuit 8 to supply another predetermined drain voltage Vd2 to the amplifier 1.

The gate voltage control circuit 7 supplies the gate voltage V g1 or V g 2 to the amplifier 1 based on the instruction from the comparison circuit 14. When the gate voltage V g 1 is supplied, the amplifier 1 performs amplification processing by class B operation to increase power supply efficiency, and when the gate voltage V g 2 is supplied, the amplifier A class A to improve distortion. Performs amplification by operation. In addition, the drain voltage control circuit 8 supplies the drain voltage Vd1 or Vd2 to the amplifier 1 based on an instruction from the comparison circuit 14. When the amplifier 1 is supplied with the drain voltage V d2, the saturation power increases whenever the drain voltage V d1 is supplied.

FIG. 9 is a diagram showing an average output power characteristic and a distortion power characteristic with respect to an average input power of the high-frequency amplifier according to Embodiment 3 of the present invention. In the figure, reference numeral 101 denotes a gate when an input signal M is input. Average output power characteristics at voltage V g 1 and drain voltage V d 1, 210 is distortion when input signal M is input to amplifier 1 and gate voltage V gl and drain voltage V d 1 The power characteristic, 202, is the distortion power characteristic when the input signal N is input to the amplifier 1 and the gate voltage Vg1 and the drain voltage Vdl, and the average output power characteristic 101, the distortion power characteristic 201 and 202 have the same characteristics as FIG. 5 of the first embodiment.

In FIG. 9, reference numeral 104 denotes an average output power characteristic when the input signal N is input and the gate voltage Vg2 and the drain voltage Vd2, and 205 denotes the input signal N to the amplifier 1. These are the distortion power characteristics when the gate voltage V g 2 and the drain voltage V d 2 are input. As shown in FIG. 9, when the input signal M is input, the peak-to-average power ratio Pr is smaller than the predetermined reference value Ps, and the gate voltage Vgl and the drain voltage Vd1 are supplied to the amplifier 1. In this case, the average output power characteristic is 101, the distortion power characteristic is 201, and the distortion power when the average output power is P1 is D1.

On the other hand, if the input signal N is input, the peak-to-average power ratio Pr is larger than the predetermined reference value Ps, and the gate voltage Vg2 and the drain voltage Vd2 are supplied to the amplifier 1, The average output power characteristic is 104, the distortion power characteristic is 205, and the distortion power when the average output power is P1 is D1 as in the case where the input signal M is input. In other words, the distortion power D2 is improved to the distortion power D1 from the distortion power D2 at the gate voltage Vg1 and the drain voltage Vdl.

The gate voltage control circuit 7 and the drain voltage control circuit 8 have a gate voltage V g1 and a drain voltage V such that the average output power characteristic 101 and the distortion power characteristic 201 can be obtained for the input signal M. In addition to d1, the gate voltage Vg2 and the drain voltage Vd2 are set so that the average output power characteristic 104 and the distortion power characteristic 205 are obtained when the input signal is N. ing. The gate voltage control circuit 7 and the drain voltage control circuit 8 determine the set gate voltage V g1 or V g2 and the set drain voltage V d1 or V d based on the instruction from the comparison circuit 14. Select 2 and supply to amplifier 1 ο

In order to obtain the average output power characteristic 104 with respect to the average output power characteristic 101, the gate voltage Vgl when the average output power characteristic 101 is obtained is increased to obtain the gate voltage Vg2. That is, by increasing the drain current of the amplifier 1 to increase the gain of the amplifier 1 and increasing the drain voltage V d 1 when the average output power characteristic 101 is obtained. The drain voltage may be Vd 2, that is, the drain voltage may be changed so that the saturation power of the amplifier 1 increases.

Further, in order to obtain the distortion power characteristic 205 with respect to the distortion power characteristic 202, the gate voltage Vg1 when obtaining the distortion power characteristic 202 is increased to increase the gate voltage Vg2. That is, the amplifier 1 is changed from the amplification processing of the class B operation to the amplification processing of the class A operation, and the drain voltage Vd1 when the distortion power characteristic 202 is obtained is increased to increase the drain voltage. The voltage may be Vd2, that is, the voltage may be changed in a direction to increase the saturation power of the amplifier 1.

As described above, the gate voltage Vg1 is increased to the gate voltage Vg2, and the drain voltage Vd1 is increased to the drain voltage Vd2, so that the amplifier 1 performs the amplification process of the class A operation. At the same time, the output back-off of the amplifier 1 increases, and the distortion power is improved as indicated by the distortion power characteristic 205.

FIG. 10 is a diagram showing another average output power characteristic with respect to the average input power of the high-frequency amplifier according to Embodiment 3 of the present invention. In the figure, the average output power characteristics 101 and 104 are the same as those in FIG. It has the same characteristics as in Fig. 9. In 105, the gate signal Vg1 when the input signal N is input and the average output power characteristic 101 is obtained is increased to the gate voltage Vg2, that is, the drain of the amplifier 1 is increased. The amplifier current is increased to increase the gain of the amplifier 1, and the drain voltage Vdl when the average output power characteristic 101 is obtained is reduced to the drain voltage Vd2 to obtain the amplifier voltage. This was changed so that the saturation power of 1 decreased. Here, the gate voltage Vg 2 and the drain voltage V d are set so that even when the input signal N is input, the same distortion power as that obtained when the input signal M is input is obtained. Just set 2. In FIG. 10, reference numeral 106 denotes a gate voltage Vg2 by reducing the gate voltage Vgl when the input signal N is input and obtaining the average output power characteristic 101. That is, by reducing the drain current of the amplifier 1, In addition to changing the gain of the amplifier 1 to decrease, the drain voltage Vd1 when the average output power characteristic 101 is obtained is increased to the drain voltage Vd2, that is, the saturation power of the amplifier 1 Is changed to increase. Here, the gate voltage Vg2 and the drain voltage Vd are set so that even when the input signal N is input, the same distortion power as the distortion power D1 when the input signal M is input is obtained. Just set 2.

When setting the gate voltage Vg2 and the drain voltage Vd2, three values can be set, as shown in the average output power characteristics 104, 105, 106 in Fig. 10. Of these three values, the one with the highest power efficiency of the amplifier 1 may be selected.

As described above, according to the third embodiment, even if the peak-to-average power ratio Pr of the input signal changes, the gate voltage Vg and the drain voltage Vd supplied to the amplifier 1 are controlled. However, the effect that the change in the distortion power output from the amplifier 1 can be suppressed is obtained. Embodiment 4.

FIGS. 11, 12, and 13 are block diagrams showing the configuration of a high frequency amplifier according to Embodiment 4 of the present invention. In each of the figures, reference numeral 9 denotes an external input to input terminal 3. This is a control terminal for inputting external instruction information such as the type of input signal to be input and the average output power of the amplifier 1 output from the output terminal 4. The gate voltage control circuit 7 (voltage control circuit) and the drain The voltage control circuit 8 (voltage control circuit) controls the gate voltage Vg and drain voltage so that the distortion power output from the amplifier 1 does not change even if the content of the external instruction information input to the control terminal 9 changes. Controls voltage Vd. The other configurations are the same as the configurations of the same reference numerals in FIGS. 4, 6, and 8 in each of the above embodiments. Next, the operation will be described.

In Fig. 11, Fig. 12, and Fig. 13, external instructions such as the type of input signal input to input terminal 3 and the magnitude of average output power of amplifier 1 output from output terminal 4 Information is input to the control terminal 9 from outside. The type of the input signal is information indicating whether the input signal is the input signal M or the input signal N in each of the above embodiments, and the magnitude of the average output power is the normal average output power or the normal output power. This is information indicating whether the average output power is higher.

When the type of input signal is input to the control terminal 9, the gate voltage control circuit 7 and the drain voltage control circuit 8 determine whether the signal input to the control terminal 9 and input to the input terminal 3 is the input signal M The gate voltage V g and the drain voltage V d can be changed by the external instruction information indicating whether the input signal N is input or the input signal N. Is controlled to be the distortion power D1 when the input signal M is input.

When the magnitude of the average output power is input to the control terminal 9, the gate voltage control circuit 7 and the drain voltage control circuit 8 determine whether the average output power is the normal average output power input to the control terminal 9. The gate voltage V g and the drain voltage V d are determined by the external instruction information indicating whether the average output power is higher than the normal output power. Control is performed so that the distortion power at the time of power becomes D1.

As described above, according to the fourth embodiment, even if the content of the external instruction information input to the control terminal 9 changes, the gate voltage V g or the drain voltage V d, or the gate voltage V g and the drain voltage By controlling the voltage Vd, an effect of suppressing a change in the distortion power output from the amplifier 1 can be obtained.

In the above embodiments, two types of input signals and two types of average output power Thus, the gate voltage Vg and the drain voltage Vd are controlled in two steps, but the input signal and the average output power are three or more types, and the gate voltage Vg and the drain voltage Vd are controlled by three levels. It is also possible to control more than stages.

In each of the above embodiments, the amplifier 1 is described as a source-grounded amplifier, but may be a gate-grounded or drain-grounded amplifier. Further, in each of the above embodiments, the amplifier 1 is described as a field-effect transistor, but may be a transistor. Industrial applicability

As described above, the high-frequency amplifier according to the present invention is suitable for suppressing a change in the output distortion power even when the peak-to-average power ratio of the input signal changes.

Claims

The scope of the claims

1. An amplifier that amplifies the input signal,

The peak-to-average power ratio is calculated by detecting the beak power and average power of the input signal, and the calculated beak-to-average power ratio is compared with a predetermined reference value. An input signal discriminating circuit for instructing to control a gate voltage or a drain voltage;

The gate voltage supplied to the amplifier so that the distortion power output from the amplifier does not change even if the peak-to-average power ratio of the input signal changes based on the instruction from the input signal determination circuit. Or a voltage control circuit for controlling the drain voltage.

A high frequency amplifier, comprising:

2. The input signal discrimination circuit

An average power detection circuit for detecting an average power of the input signal;

A peak power detection circuit for detecting a peak power of the input signal,

A power ratio calculation circuit that calculates a peak-to-average power ratio based on the average power of the input signal detected by the average power detection circuit and the peak power of the input signal detected by the beak power detection circuit; ,

The peak-average power ratio calculated by the power ratio calculation circuit is compared with a predetermined reference value, and based on the comparison result, a gate voltage or a drain voltage supplied to the amplifier is supplied to the voltage control circuit. And a comparison circuit that instructs

2. The high-frequency amplifier according to claim 1, wherein the high-frequency amplifier is provided.

3. The voltage control circuit calculates the peak gain calculated by the input signal determination circuit. Increases the gate voltage supplied to the amplifier when the average power ratio is higher than the predetermined reference value, compared to when the average power ratio is lower than the predetermined reference value.

2. The high-frequency amplifier according to claim 1, wherein:

4-The voltage control circuit, when the peak-to-average power ratio calculated by the input signal discriminating circuit is higher than a predetermined reference value, than when the peak-to-average power ratio is lower than the predetermined reference value Also increase the drain voltage supplied to the amplifier

2. The high-frequency amplifier according to claim 1, wherein:

5. An amplifier that amplifies the input signal,

Detects the peak power and average power of the input signal, calculates the peak-to-average power ratio, compares the calculated peak-to-average power ratio with a predetermined reference value, and supplies the amplifier based on the comparison result. An input signal discrimination circuit for instructing to control a gate voltage and a drain voltage,

The gate voltage supplied to the amplifier so that the distortion power output from the amplifier does not change even if the beakage-to-average power ratio of the input signal changes based on the instruction from the input signal determination circuit. And a voltage control circuit for controlling the drain voltage.

A high frequency amplifier, comprising:

6. The input signal determination circuit

A peak power detection circuit for detecting a peak power of the input signal,

The average power of the input signal detected by the average power detection circuit; A power ratio calculation circuit that calculates a peak-to-average power ratio based on the beak power of the input signal detected by the peak power detection circuit;

The peak-to-average power ratio calculated by the power ratio calculation circuit is compared with a predetermined reference value. Based on the comparison result, the gate voltage and the drain voltage supplied to the amplifier are supplied to the voltage control circuit. And a comparison circuit that instructs

6. The high-frequency amplifier according to claim 5, wherein the high-frequency amplifier is provided.

7. If the peak-to-average power ratio calculated by the input signal discriminating circuit is higher than the predetermined reference value, the voltage-control circuit sets the peak-to-average power ratio to be lower than the predetermined reference value. If necessary, increase the gate voltage supplied to the amplifier and increase the drain voltage supplied to the amplifier.

6. The high-frequency amplifier according to claim 5, wherein:

8. When the peak-to-average power ratio calculated by the input signal discriminating circuit is higher than a predetermined reference value, the voltage control circuit operates when the peak-to-average power ratio is lower than the predetermined reference value. Also increases the gate voltage supplied to the amplifier and decreases the drain voltage supplied to the amplifier.

6. The high-frequency amplifier according to claim 5, wherein:

9. When the peak-to-average power ratio calculated by the input signal discriminating circuit is higher than a predetermined reference value, the voltage control circuit operates when the peak-to-average power ratio is lower than the predetermined reference value. Furthermore, while reducing the gate voltage supplied to the amplifier, the drain voltage supplied to the amplifier is increased. Let

6. The high-frequency amplifier according to claim 5, wherein:

10. An amplifier that amplifies the input signal,

Input external instruction information such as the type of input signal input to the amplifier and the magnitude of the average output power output from the amplifier, and output from the amplifier even if the content of the input external instruction information changes. A gate voltage or a drain voltage to be supplied to the amplifier or a voltage control circuit for controlling the gate voltage and the drain voltage so that the distortion power does not change.

A high frequency amplifier, comprising: