JP4293943B2 - High frequency power amplifier - Google Patents

Description

  The present invention relates to a high frequency power amplifier using a field effect transistor or a bipolar transistor as a power high frequency transistor.

FIG. 9 shows a conventional high-frequency power amplifier.
In this example, it is composed of a high-frequency transistor 1 having a single stage for amplifying a high-frequency signal and an output matching circuit thereof. A is a high frequency signal input terminal, B is a DC power supply terminal, and C is a high frequency signal output terminal. There is also a final stage of a high-frequency power amplifier composed of two or more stages of high-frequency transistors.

  A direct current is supplied from the direct current power supply terminal B to the drain of the high frequency transistor 1 via the bias circuit 8. Specifically, the bias circuit 8 is normally configured by a bias line 3 that secures a length corresponding to λ / 4 of a fundamental frequency (0.9 GHz to 1.0 GHz). The bias line 3 is designed to have such a length that the fundamental impedance is sufficiently higher than the transmission line 2 on the power supply side to the high-frequency transistor 1.

  If the length of the quarter wavelength of the fundamental frequency cannot be secured as the bias line 3, the capacitor 5 equivalently converts the electrical length of the fundamental bias line into the equivalent of the quarter wavelength electrical length. ing.

The capacitor 4 connected to the DC power supply terminal B side of the bias line 3 is a bypass capacitor of about 1000 pF.
On the output side of the high-frequency transistor 1, as an output matching circuit for obtaining desired output characteristics, an output matching circuit for matching the impedance of the output external circuit of the high-frequency power amplifier with the internal impedance of the high-frequency transistor 1 for the fundamental wave 7 and a harmonic processing circuit 6 that optimizes the high-order harmonic impedance. For example, in the case of class F amplification operation, the harmonic processing circuit 6 is configured to short-circuit even-order harmonics and open odd-numbered harmonics.

In a one-stage high-frequency amplifier, the general harmonic processing of class F operation is designed such that the second harmonic impedance is short-circuited and the third harmonic impedance is opened, and higher harmonics of the fourth order or higher are used. Harmonic power is ignored because the power is relatively small compared to the second and third harmonics. The second and third harmonics are processed by a circuit using a short stub or an open stub.
Japanese Patent Laid-Open No. 9-238001 JP 2000-165163 A

  The conventional high-frequency power amplifier has a change in internal capacitance due to variations in the diffusion process of the high-frequency transistor 1, and the GND distance and line of the stripline and microstripline used for the bias line 3, the harmonic processing circuit 6, and the output matching circuit 7. Due to variations in width, there is a problem that the optimum impedances of the second harmonic and the third harmonic required for the fundamental wave and class F operation are shifted.

  Therefore, in the adjustment work for correcting the impedance deviation, the impedance deviation caused by the high-frequency transistor 1 and the strip line or microstrip line is corrected by changing the lumped constant elements used in the harmonic processing circuit 6 and the output matching circuit 7. The impedance adjustment is performed in the order of the fundamental wave and the second harmonic, and the third harmonic of the fundamental frequency used in a normal mobile phone device is 2 GHz or more, which is the self-resonance of the lumped constant element. Since the frequency is exceeded, it is difficult to optimally match the impedance of higher harmonics such as third harmonics.

  Also, in recent years, the thinning of sets using high-frequency power amplifiers has accelerated, and the distance between the mounting electrode land of the high-frequency power amplifier designed in the set and the GND under the land has also been reduced. A small capacitance is generated in the electrode land. In particular, in a high-frequency amplifier that achieves high efficiency by class F operation, if an external microcapacitance is added to the DC power supply terminal B of the bias line 3 of the high-frequency transistor 1, the bias line 3 and the external microcapacitor Resonates and shifts the phase of the higher harmonic impedance from the optimum position.

  The object of the present invention is to change the internal capacitance of the high-frequency transistor 1 due to variations in the diffusion process of the high-frequency transistor 1 and the GND distance of the stripline and microstripline used in the bias line 3, harmonic processing circuit 6, and output matching circuit 7. In the state where the impedance has deviated from the optimum position due to the influence of external micro-capacitance such as the influence of variations in line width and the influence of external micro-capacity such as the micro-capacitance generated on the mounting electrode land of the set on which the high-frequency power amplifier is mounted. An object of the present invention is to provide a high-frequency power amplifier capable of controlling the phase of the third harmonic to an optimum position where the power efficiency is maximized without affecting the impedance of the second harmonic.

A high-frequency power amplifier according to the present invention includes a high-frequency transistor, a bias circuit connected to an output side of the high-frequency transistor and including a distributed constant line for supplying a direct current to the transistor and a bypass capacitor, and a harmonic load of the transistor A harmonic processing circuit that controls the fundamental impedance of the transistor to an optimal impedance position, and a harmonic phase control circuit connected to the power supply side of the bias circuit. The harmonic phase control circuit is constituted by a series circuit of an inductor and a capacitor, one end of which is grounded, and controls the phase of a desired higher order harmonic.

  In particular, for example, when the inductor of the harmonic phase control circuit installed on the DC power supply side of the bias line is configured as one chip component of a winding structure and the capacitor is configured as one chip component of a multilayer structure, the chip inductor is The high-order harmonic of the self-resonant frequency has an inductance value that is not applied to the third-order harmonic, and the chip capacitor is several hundred pF or more that the self-resonant frequency does not apply to the frequency higher than the fundamental wave. In this case, the combined inductance component of the chip inductor installed on the DC power supply side of the bias line and the chip capacitor connected in series and the bypass capacitor connected in parallel with these harmonic phase control circuits Since the inductance components of the are combined to change the electrical length of the bias line at high frequencies, It affects only the phase of the third harmonic impedance at the output load. As a result, by controlling the inductance value of the inductor installed on the DC power supply side of the bias line, it is possible to control only the phase of the third harmonic impedance in the output load of the transistor.

  Furthermore, the high-frequency power amplifier of the present invention includes a high-frequency transistor, a bias circuit connected to the output side of the high-frequency transistor and including a distributed constant line for supplying a direct current to the transistor and a bypass capacitor, and harmonics of the transistor. A harmonic processing circuit for controlling the load to the optimum impedance position, an output matching circuit for controlling the load of the fundamental wave of the transistor to the optimum impedance position, and a harmonic phase control circuit connected to the power supply side of the bias circuit. The harmonic phase control circuit is composed of a parallel circuit of a series circuit of an inductor, a first capacitor, and a second capacitor, one end of which is grounded and controls the phase of a desired higher-order harmonic. And

  In particular, for example, in the case of a series circuit inductor and capacitor installed on the DC power supply side of the bias line, when the inductor is configured as one winding chip component and the capacitor is configured as one multilayer chip component, The inductor has an inductance value that does not cause the self-resonant frequency to be applied to high-order harmonics, specifically, the third-order harmonic, and the chip capacitor has several hundreds that do not apply the self-resonant frequency to frequencies higher than the fundamental wave. It has a capacitance value of pF or more. One capacitor grounded in parallel with the series circuit of the inductor and the capacitor on the DC power supply side of the bias line has a small capacitance component.

  According to this configuration, the combined inductance component of the chip inductor installed on the DC power supply side of the bias line and the capacitor connected in series and the inductance component of the bypass capacitor connected in parallel with these harmonic phase control circuits are Since it is synthesized and changes the electrical length of the bias line at high frequencies, it only affects the phase of the third harmonic impedance at the output load of the transistor. In addition, the resonance between the bias line and the capacitor having a small capacitance value installed on the DC power supply side of the bias line affects only the phase of the third harmonic impedance in the output load of the transistor.

  As a result, the output value of the transistor is controlled by controlling the inductance value of the series circuit of the inductor and the capacitor installed on the DC power supply side of the bias line and the capacitance value of the small capacitor installed in parallel to the series circuit. The control of only the phase of the third harmonic impedance is realized in FIG.

  According to the high-frequency power amplifier of the present invention, the phase of the high-order harmonic, specifically, the third-order harmonic impedance can be controlled by utilizing the resonance between the capacitor and the bias circuit. It is possible to improve the influence on the phase of the third harmonic impedance due to variations in internal capacitance and impedances of the distributed constant line of the substrate. Furthermore, even if the distributed line such as the bias line is about 2mm short in the trial production, the phase of the 3rd harmonic impedance can be controlled, so that the development efficiency and the high yield can be improved during the trial production and mass production. realizable. That is, a high-efficiency high-frequency amplifier can be realized by optimally matching the phase of the third harmonic of the final stage transistor.

The same effect can be obtained even if the bypass capacitor is installed outside the DC power supply terminal of the high frequency power amplifier.
In addition, according to the high frequency power amplifier of the present invention, high-order harmonics in the direction of returning the electrical length of the bias line from the short state to the original state by controlling the inductance component by the high frequency phase control circuit and the bypass capacitor, specifically, Since the phase of the 3rd harmonic impedance can be controlled, the influence on the phase of the 3rd harmonic impedance due to the dispersion of the internal capacitance accompanying the diffusion process of the transistor of the high frequency power amplifier and the impedance of the distributed constant line of the substrate is improved. Is possible. Furthermore, even if the distributed constant line such as the bias line is about 1.5 mm long in the trial production, it is possible to control the phase of the 3rd harmonic impedance. Yield can be realized.

  Furthermore, according to the high frequency power amplifier of the present invention, it is possible to control the high order harmonic, specifically the phase of the third harmonic impedance, using the resonance of the capacitor and the bias circuit of the high frequency phase control circuit, and the high frequency phase control. By controlling the inductance component of the circuit and the bypass capacitor, the electrical length of the bias line can be made shorter and the phase of the third harmonic impedance can be controlled. It is possible to improve the influence of the third-order harmonic impedance on the phase due to the impedance variation of the distributed constant line. Furthermore, the phase of the third harmonic impedance can be controlled even when the distributed constant line such as the bias line is away from the optimum position in the range of about -1.5 mm to +2 mm in the trial production. In this way, it is possible to achieve development efficiency and high yield.

  Furthermore, according to the high frequency power amplifier of the present invention, the electrical length of the bias line is controlled by controlling the inductance component of the high frequency phase control circuit and the bypass capacitor, and the external load loaded on the mounting electrode land of the high frequency power amplifier The influence on the phase of high-order harmonics, specifically, the third-order harmonic impedance due to the minute capacitance component can be canceled. Thereby, the high frequency power amplifier can improve the characteristic deterioration due to the external minute capacitance component loaded on the mounting electrode land due to the thinning of the mounted set, and can contribute to the thinning of the set.

Hereinafter, embodiments of the present invention will be described with reference to FIGS.
Note that the case of a high-frequency power amplifier having a desired pass frequency band of 0.9 GHz to 1.0 GHz will be described as an example, but the pass frequency band is not limited to the above frequency band. Further, the case where the third harmonic is controlled will be described in detail. However, the same can be applied to the case where a desired second or higher harmonic is controlled.

  Further, in the following description, a circuit configuration in which the bias line length is λ / 12 and the fundamental impedance is converted to λ / 4 by the impedance conversion capacitor 5 is taken as an example. Further, for the sake of simplicity, the rotation of the phase is displayed on the Smith chart with a counterclockwise plus.

(First embodiment)
FIG. 1 shows a high-frequency power amplifier according to a first embodiment of the present invention.
This high-frequency power amplifier differs from the conventional example shown in FIG. 9 only in that a high-frequency phase control circuit 9 is connected to the DC power supply terminal B side of the bias circuit 8, and the other configurations are the same as those of the conventional example. Similar to the example.

  The high frequency phase control circuit 9 in the first embodiment is configured such that one end is grounded and the other end is connected to the power supply side of the bias circuit 8. The harmonic phase control circuit 9 is composed of a capacitor 10 that controls the phase of a desired higher-order harmonic to an optimum position for power efficiency. The capacitor 10 in the case where the fundamental frequency band is 0.9 GHz to 1.0 GHz band is set to a capacitance value range of 0 to 3 pF.

  By setting the capacitance value of the capacitor 10 in the range of 0 to 3 pF, the phase of the third harmonic in the 2.7 GHz to 3 GHz band can be controlled in the range of about 0 ° to −20 °. This phase change corresponds to increasing the electrical length by about 2 mm in the bias line 3 having a width of 400 μm set to an impedance of about 33Ω, and the actual high-frequency transistor 1, high-frequency processing circuit 6, and output matching circuit 7. The influence of the third-order harmonic impedance on the phase due to the variation of the distributed constant line used in the circuit is about ± 5 °, which is sufficient to control the phase in the clockwise direction.

(Second Embodiment)
FIG. 2 shows a high frequency power amplifier according to a second embodiment of the present invention.
This high-frequency power amplifier differs from the conventional example shown in FIG. 9 only in that a high-frequency phase control circuit 9 is connected to the DC power supply terminal B side of the bias circuit 8, and the other configurations are the same as those of the conventional example. Similar to the example.

The high-frequency phase control circuit 9 is composed of a series circuit of an inductor 11 and a capacitor 12 that are grounded at one end and control the phase of a desired high-order harmonic to an optimum position for power efficiency.
The inductor 11 is adjusted within a range of about 10 nH or less so that the self-resonant frequency is not applied to the third harmonic, and the capacitor 12 is several hundred pF so that the self-resonant frequency is applied to the frequency above the fundamental wave and the impedance is not affected. The above capacitance value, specifically, a capacitance value of 1000 pF is set.

  According to this configuration, the 2.7 GHz to 3.0 GHz band of the third harmonic sufficiently exceeds the self-resonant frequency of the capacitor 12 in which the chip capacitor of 1000 pF is used. In the frequency band of the third harmonic, The capacitor 12 exhibits inductivity.

  Therefore, the high-frequency phase control circuit 9 shows a combined inductance component of the inductive components of the inductor 11 and the capacitor 12 in the third-harmonic frequency band. Further, in this third harmonic frequency band, the bypass capacitor 4 of the bias circuit 8 also exhibits inductivity, and the combined inductance of this inductance component and the inductance component of the harmonic phase control circuit 9 acts on the electrical length of the bias line. To do.

  The inductance component of a 0603 size 1000 pF capacitor that is generally used is about 0.5 nH in the vicinity of the 2.7 GHz to 3.0 GHz band, and the inductor 11 of the high-frequency phase control circuit 9 is controlled in the range of 0 nH to 10 nH. Thus, the combined inductance of the high-frequency phase control circuit 9 and the bypass capacitor 4 varies in the range of about 0.25 nH to 0.5 nH, and the phase of the third harmonic impedance can be controlled in the range of about 0 ° to + 15 °. This change in phase angle has an effect equivalent to a state in which the electrical length is shortened by about 1.5 mm in a 400 μm wide bias line set to an impedance of about 33Ω.

  The influence on the phase of the third harmonic impedance due to the variation of the distributed constant lines used in the actual high-frequency transistor 1 and the high-frequency processing circuit 6 and the output matching circuit 7 is about ± 5 °, and the phase is counterclockwise. This is a sufficient effect to control.

(Third embodiment)
FIG. 3 shows a high-frequency power amplifier according to the third embodiment of the present invention.
This high-frequency power amplifier differs from the conventional example shown in FIG. 9 only in that a high-frequency phase control circuit 9 is connected to the DC power supply terminal B side of the bias circuit 8, and the other configurations are the same as those of the conventional example. Similar to the example.

  The high-frequency phase control circuit 9 is a parallel circuit of a series circuit of an inductor 14 and a first capacitor 15 and a second capacitor 13, which is grounded at one end and controls the phase of a desired high-order harmonic to an optimum position for power efficiency. It is comprised by. In the case where the fundamental frequency band is 0.9 GHz to 1.0 GHz, the inductor 14 is adjusted within a range of about 10 nH or less so that the self-resonant frequency is not applied to the third harmonic, and the first capacitor 15 has a self-resonant frequency. A capacitance value of several hundred pF or more, specifically, a capacitance value of 1000 pF is set so as not to affect the impedance above the fundamental wave. The second capacitor 13 is controlled within a capacitance value range of about 3 pF exceeding 0 pF.

  According to this configuration, the phase of the third harmonic impedance can be controlled in the clockwise direction by the minute second capacitor 13 whose end point is grounded to the DC power supply terminal B. The third harmonic impedance can be controlled in the counterclockwise direction by a combined inductance component of the inductance component of the inductor 14 to which the end point is connected and the inductance component of the first capacitor 15. Furthermore, the third harmonic impedance can be controlled in the clockwise direction by increasing the inductance component of the inductor 14.

  Further, by setting the second capacitor 13 to about 1000 pF, which is the same as the first capacitor 15, the combined inductance of the harmonic phase control circuit 9 and the bypass capacitor 5 is further reduced, and the second embodiment shown in FIG. The phase can be rotated in the counterclockwise direction more than in the case of the form.

  The phase of the third harmonic impedance can be controlled in a range of about 0 ° to −20 ° by the second capacitor 13 having the same effect as the capacitor 10 of FIG. 1 when the initial position is set to 0 °. The inductor 14 having the same effect as the inductor 11 of FIG. 2 and the first capacitor 15 of 1000 pF can be controlled in the range of about 0 ° to + 25 °.

  Therefore, the phase control range of the third harmonic impedance can be greatly expanded by the harmonic phase control circuit 9, which is about 4.5 mm in a bias line having a width of 400 μm set to an impedance of about 33Ω. There is an effect equivalent to operating the electrical length of the minute.

  The third order when the capacitance value of the second capacitor 13 exceeds 0 pF and is 3 pF or less, the capacitance value of the first capacitor 15 is 1000 pF, and the inductance value of the inductor 14 exceeds 0 nH and is less than 10 nH. FIG. 7 shows changes in the phase of the harmonic impedance and the efficiency of the high-frequency power amplifier. Further, FIG. 8 shows the movement of the phase of the impedance of the fundamental wave, the second harmonic, and the third harmonic during the harmonic phase control.

(Fourth embodiment)
FIG. 4 shows a high-frequency power amplifier according to a fourth embodiment of the present invention.
In each of the above-described embodiments, the case where the wiring board on which the electric circuit of the high-frequency power amplifier is constructed is properly adjusted in the state before being mounted on the main board of the mobile phone device has been described as an example. In this embodiment, a case where the wiring board on which the electric circuit of the high-frequency power amplifier is constructed is properly adjusted in a state where the wiring board is mounted on the main board of the mobile phone device is specifically described.

  The high-frequency power amplifier mounted on the main board of the cellular phone device is in a state in which the external minute capacitor 16 on the main board side is added to the DC power supply terminal B. Specifically, a high frequency power amplifier is mounted on the main board, and the DC power supply terminal B of the high frequency power amplifier is fed and operated through a mounting electrode land (not shown) of the main board. In the adjustment, the external microcapacitor 16 is a parasitic stray capacitance generated in the mounting electrode land of the main substrate.

  In this case, the phase of the third harmonic impedance is rotated in the clockwise direction by the external microcapacitor 16, and the third harmonic impedance is controlled in the counterclockwise direction by the inductance component of the inductor 11 and the bypass capacitor 4. be able to. Furthermore, the third harmonic impedance can be controlled in the clockwise direction by increasing the inductance component of the high frequency phase control circuit 9.

  The phase of the third harmonic impedance rotates in the clockwise direction due to the influence of the external microcapacitor 16 in FIG. 4 when the initial position is set to 0 °, but due to the combined inductance of the high frequency phase control circuit 9 and the bypass capacitor 4 Since the inductance component becomes small, the electrical length of the bias line 3 can be made shorter, and the phase of the third harmonic impedance can be returned to the counterclockwise direction by about + 15 °. When the counterclockwise direction is excessive, the phase control inductor 17 in the high-frequency phase control circuit 9 can be increased to control the clockwise direction.

  However, when the external microcapacitance 16 exceeds 3 pF, it is difficult to return the phase of the third harmonic impedance only by this circuit, but the influence of the external microcapacitance 16 can be suppressed as much as possible.

  Note that, in the case of the third embodiment shown in FIG. 3, as in the case of the fourth embodiment, when the high-frequency power amplifier is mounted on the main board of the mobile phone device, the adjustment is performed. By adjusting the high-frequency phase control circuit 9, the phase of the higher harmonics such as the third harmonic is adjusted to the optimum value that maximizes the power efficiency without affecting the impedance of the fundamental wave and the second harmonic. it can.

  Further, if it is seen that the external microcapacitance 16 of the fourth embodiment and the second capacitor 13 of the third embodiment shown in FIG. In the third embodiment, the same effect can be obtained even if the second capacitor 13 is installed outside the DC power supply terminal of the high frequency power amplifier, instead of inside the substrate on which the high frequency power amplifier is constructed. Specifically, it may be configured to be provided on the main board side of a mobile phone device or the like on which a high frequency power amplifier is mounted.

(Fifth embodiment)
FIG. 5 shows a high frequency power amplifier according to a fifth embodiment of the present invention.
This high-frequency power amplifier differs from the conventional example shown in FIG. 9 only in that a high-frequency phase control circuit 9 is connected to the DC power supply terminal B side of the bias circuit 8, and the other configurations are the same as those of the conventional example. Same as example.

The high-frequency phase control circuit 9 includes an open stub 19 having a base end connected to the power supply side of the bias circuit 8 and the other end opened.
The open stub 19 is adjusted in length, width, and distance between the line and GND in a range corresponding to a capacitance value exceeding about 0 to 3 pF.

  By controlling the open stub 19 in a capacitance value range exceeding 0 to 3 pF, the phase of the third harmonic in the 2.7 GHz to 3 GHz band can be controlled in the range of about 0 ° to −20 °. . This phase change has an effect equivalent to increasing the electrical length by about 2 mm in a 400 μm wide bias line set to an impedance of about 33Ω.

  The influence on the phase of the third harmonic impedance due to the variation of the distributed constant line used in the actual high frequency transistor 1 or the high frequency processing circuit 6 and the output matching circuit 7 is about ± 5 °, and the phase is clockwise. This is a sufficient effect to control.

(Sixth embodiment)
FIG. 6 shows a high frequency power amplifier according to a sixth embodiment of the present invention.
This high-frequency power amplifier is obtained by replacing the second capacitor 13 in the third embodiment shown in FIG. 3 with an open stub 20, and the other configurations are the same as those in the third embodiment.

  In the sixth embodiment, the wiring board on which the electric circuit of the high-frequency power amplifier is constructed is described as an example in which the wiring board is appropriately adjusted in a state before being mounted on the main board of the mobile phone device. Even when the external microcapacitor 16 on the main board side is added to the DC power supply terminal B by mounting the wiring board on which the electric circuit of the high frequency power amplifier is constructed on the main board of the mobile phone device, the high frequency power amplifier Similarly, it can be appropriately adjusted by the phase control circuit 9.

  In each of the above embodiments, a field effect transistor is used as the high-frequency transistor 1, but a bipolar transistor can also be used.

  The high-frequency power amplifier according to the present invention can realize a high-efficiency high-frequency amplifier by controlling only the phase of a desired higher-order harmonic to an optimum position, and is useful as a wireless device or the like.

1 is a circuit diagram of a first embodiment of a high-frequency power amplifier according to the present invention. The circuit diagram of 2nd Embodiment of the high frequency power amplifier based on this invention The circuit diagram of 3rd Embodiment of the high frequency power amplifier based on this invention 4 is a circuit diagram of a fourth embodiment of a high-frequency power amplifier according to the present invention. The circuit diagram of 5th Embodiment of the high frequency power amplifier based on this invention Circuit diagram of sixth embodiment of high-frequency power amplifier according to the present invention Relationship diagram between phase of third harmonic impedance and efficiency characteristic according to third embodiment Relationship diagram between the fundamental wave and the phase of the second harmonic impedance when the phase of the third harmonic impedance is controlled according to the third embodiment Circuit diagram of conventional high-frequency power amplifier

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 High frequency transistor 2 Transmission line 3 Bias line 4 Bypass capacitor 5 Impedance conversion capacitor 6 Harmonic processing circuit 7 Output matching circuit 8 Bias circuit 9 High frequency phase control circuit 10 Phase control capacitor 11 Phase control inductor 12 Capacitor 13 Phase control capacitor 14 Phase control Inductor 15 Capacitor 16 External micro capacitance 19 Phase control open stub 20 Phase control open stub A High frequency signal input terminal B DC power supply terminal C High frequency signal output terminal

Claims (2)

A high-frequency transistor;
A bias circuit connected to the output side of the high-frequency transistor and including a distributed constant line and a bypass capacitor for supplying a direct current to the transistor;
A harmonic processing circuit for controlling the harmonic load of the transistor to an optimum impedance position;
An output matching circuit that controls the load of the fundamental wave of the transistor to an optimum impedance position;
A harmonic phase control circuit connected to the power supply side of the bias circuit, and the harmonic phase control circuit is configured by a series circuit of an inductor and a capacitor, one end of which is grounded and controls a phase of a desired higher order harmonic. Configured high-frequency power amplifier. A high-frequency transistor;
A bias circuit connected to the output side of the high-frequency transistor and including a distributed constant line and a bypass capacitor for supplying a direct current to the transistor;
A harmonic processing circuit for controlling the harmonic load of the transistor to an optimum impedance position;
An output matching circuit that controls the load of the fundamental wave of the transistor to an optimum impedance position;
A harmonic phase control circuit connected to the power supply side of the bias circuit, the harmonic phase control circuit having one end grounded and controlling a phase of a desired higher-order harmonic, and an inductor and a first capacitor A high frequency power amplifier composed of a parallel circuit of a series circuit and a second capacitor.

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