WO2023078062A1

WO2023078062A1 - Doherty radio frequency power amplifier

Info

Publication number: WO2023078062A1
Application number: PCT/CN2022/125438
Authority: WO
Inventors: 彭艳军; 宣凯; 郭嘉帅
Original assignee: 深圳飞骧科技股份有限公司
Priority date: 2021-11-05
Filing date: 2022-10-14
Publication date: 2023-05-11
Also published as: CN216390917U

Abstract

Provided in the embodiments of the present utility model is a Doherty radio frequency power amplifier, comprising a drive amplifier, a carrier input matching network, a carrier power amplifier, a peak input matching network, a peak power amplifier, a first output matching network and a second output matching network. The carrier input matching network and the first output matching network each comprise a phase compensation network for 90-degree phase shift and impedance transformation; and the phase compensation network comprises a high-pass T-type network, a high-pass π-type network, a low-pass T-type network and a low-pass π-type network. The Doherty radio frequency power amplifier of the present utility model is small in layout area and high in power added efficiency.

Description

Doherty RF Power Amplifier

technical field

The utility model relates to the technical field of radio frequency integrated circuits, in particular to a Doherty radio frequency power amplifier.

Background technique

In order to make full use of spectrum resources and increase the data transmission rate in modern wireless communication systems, the peak-to-average ratio (PAPR) signal format is adopted for modulation signals. High peak-to-average ratio signals impose strict requirements on the linearity of RF power amplifiers. In order to ensure the undistorted transmission of the signal, the wireless communication system requires the RF power amplifier to work in a power back-off state far away from the power compression point, so as to ensure the linear amplification of the RF signal. However, the efficiency of RF power amplifiers is often designed to have the highest efficiency near the saturation region, and the efficiency at the power back-off point is significantly reduced. In order to improve the efficiency of RF power amplifiers during power back-off, the Doherty structure is a common method for designing RF power amplifiers.

A Doherty radio frequency power amplifier in the related art generally includes a driver amplifier, a power divider, a main power amplifier, an auxiliary power amplifier, a power combiner and a quarter-wavelength transmission line. Please refer to Figure 1, which is a schematic diagram of the circuit structure of a Doherty RF power amplifier in the related art, wherein, after the input signal is amplified by the drive amplifier, the input power is divided into two through the power divider, and one road is input to the main power amplifier. The other is connected to the input of the auxiliary power amplifier after passing through a quarter-wavelength transmission line. The output of the main power amplifier is connected to the first input of the power combiner through a quarter-wavelength transmission line, the output of the auxiliary power amplifier is directly connected to the second input of the power combiner, and the output of the power combiner is connected to the output load . The working principle of the Doherty RF power amplifier in the related art is: the main power amplifier is biased at Class AB or Class B, and the auxiliary power amplifier is biased at Class C. In the low output power state, the auxiliary power amplifier is turned off, and the load impedance of the main power amplifier is 2Ropt. In the state of high output power, the auxiliary power amplifier is turned on, the load impedance of the main power amplifier changes from 2Ropt to Ropt with the increase of input power, and the load impedance of the auxiliary power amplifier also gradually decreases from infinite value to Ropt with the increase of input power, The outputs of the two amplifiers are combined by a power combiner. Due to this change in load modulation, the Doherty RF power amplifier exhibits higher efficiency when power is backed off.

However, the size of the power splitter and the quarter-wavelength transmission line of the Doherty RF power amplifier in the related art is too large to be implemented on a chip, especially in the Sub-6GHz frequency band. longer. The small-scale characteristics of monolithic microwave integrated circuits require that small-sized passive devices must be used when designing Doherty RF power amplifiers using integrated circuit technology.

Therefore, it is necessary to provide a novel broadband Doherty radio frequency power amplifier with compact size and achievable integrated circuit technology to solve the above problems.

Utility model content

Aiming at the above deficiencies in the prior art, the utility model proposes a Doherty radio frequency power amplifier with small layout area and high power added efficiency.

In order to solve the above-mentioned technical problem, the embodiment of the present utility model provides a kind of Doherty radio frequency power amplifier, it comprises driver amplifier, carrier input matching network, carrier power amplifier, peak input matching network, peak power amplifier, first output matching network and a second output matching network;

The input end of described driving amplifier is used as the input end of described Doherty radio frequency power amplifier;

The output end of the drive amplifier is respectively connected to the input end of the carrier input matching network and the input end of the peak input matching network;

The output terminal of the carrier input matching network is connected to the input terminal of the carrier power amplifier;

The output terminal of the carrier power amplifier is connected to the input terminal of the first output matching network;

The output terminal of the peak input matching network is connected to the input terminal of the peak power amplifier;

The output end of the peak power amplifier is respectively connected to the input end of the second output matching network and the output end of the first output matching network;

The output end of the second output matching network is used as the output end of the Doherty radio frequency power amplifier for connecting the system load;

Wherein, both the carrier input matching network and the first output matching network include a phase compensation network for 90-degree phase shift and impedance transformation;

The phase compensation network is any one of a high-pass T-type network, a high-pass π-type network, a low-pass T-type network and a low-pass π-type network.

Preferably, the carrier input matching network is a high-pass T-type network or a high-pass π-type network; the first output matching network is a low-pass T-type network or a low-pass π-type network.

Preferably, the carrier input matching network is a high-pass T-type network; the first output matching network is a low-pass π-type network.

Preferably, the driving amplifier, the carrier power amplifier and the peak power amplifier are all implemented by transistors.

Preferably, the carrier input matching network includes a third inductor, a second capacitor and a third capacitor; the first end of the second capacitor serves as the input end of the carrier input matching network, and the first end of the second capacitor One end is connected to the collector of the first transistor; the second end of the second capacitor is respectively connected to the first end of the third capacitor and the first end of the third inductor; the third inductor The second end of the third capacitor is connected to the ground; the second end of the third capacitor is used as the output end of the carrier input matching network;

The first output matching network includes a fifth capacitor, a sixth capacitor, and a fourth inductor; the first end of the fourth inductor serves as an input end of the first output matching network, and the first end of the fourth inductor terminals are respectively connected to the collector of the second transistor and the first terminal of the fifth capacitor; the second terminal of the fourth inductance is used as the output terminal of the peak power amplifier, and the first terminal of the fourth inductance The two terminals are connected to the first terminal of the sixth capacitor; the second terminal of the fifth capacitor is connected to the ground; the second terminal of the sixth capacitor is connected to the ground.

Preferably, the drive amplifier includes a first inductor, a second inductor, a first capacitor, a first transistor, and a first bias circuit; the first end of the first capacitor is used as the input end of the drive amplifier, and the The first terminal of the first capacitor is connected to ground after being connected in series with the first inductor, and the second terminal of the first capacitor is respectively connected to the base of the first transistor and the output of the first bias circuit terminal, the emitter of the first transistor is connected to ground, the collector of the first transistor is used as the output terminal of the drive amplifier, and the collectors of the first transistor are respectively connected to the second end, the input end of the carrier input matching network and the input end of the peak input matching network; the first end of the second inductance is connected to the power supply voltage; the input end of the first bias circuit is connected to the reference voltage .

Preferably, the carrier power amplifier includes a second bias circuit and a second transistor; the base of the second transistor is used as the input terminal of the carrier power amplifier, and the bases of the second transistor are respectively connected to the The second terminal of the third capacitor and the output terminal of the second bias circuit; the emitter of the second transistor is connected to ground; the collector of the second transistor is used as the output terminal of the carrier power amplifier; The input end of the second bias circuit is connected to a reference voltage.

Preferably, the peak input matching network includes a fourth capacitor; the first end of the fourth capacitor is used as the input end of the peak input matching network, and the first end of the fourth capacitor is connected to the first The collector of the transistor; the second terminal of the fourth capacitor is used as the output terminal of the peak input matching network;

The peak power amplifier includes a third bias circuit and a third transistor; the base of the third transistor is used as the input of the peak power amplifier, and the base of the third transistor is connected to the fourth capacitor The second terminal of the second terminal and the output terminal of the third bias circuit; the emitter of the third transistor is connected to the ground; the collector of the third transistor is used as the output terminal of the peak power amplifier; the third The input terminal of the bias circuit is connected to a reference voltage.

Preferably, the second output matching network includes a fifth inductor, a sixth inductor, a seventh inductor, a seventh capacitor, and an eighth capacitor; the first end of the fifth inductor is used as an input of the second output matching network end, and the first end of the fifth inductance is respectively connected to the collector of the third transistor and the second end of the sixth inductance; the first end of the sixth inductance is connected to a power supply voltage; the The second end of the fifth inductor is respectively connected to the first end of the seventh capacitor and the first end of the eighth capacitor; the second end of the seventh capacitor is connected to ground; the first end of the eighth capacitor The two terminals serve as the output terminals of the second output matching network, and the second terminal of the eighth capacitor is connected to the first terminal of the seventh inductor; the second terminal of the seventh inductor is connected to ground.

Preferably, the carrier input matching network, the peak input matching network, the first output matching network and the second output matching network are all lumped parameter circuits.

Compared with the related art, the Doherty radio frequency power amplifier of the present utility model removes the larger power divider of the related art, the carrier input matching network is set in front of the input end of the carrier power amplifier, and the peak input is set in front of the input end of the peak power amplifier. matching network. This setting enables uniform or non-uniform power distribution of the input power through the impedance value of the carrier input matching network and the impedance value of the peak input matching network, thereby replacing a power divider with a large size. The output terminal of the carrier power amplifier is connected to the input terminal of the first output matching network, and both the carrier input matching network and the first output matching network include a phase compensation network for 90-degree phase shift and impedance transformation. This structure enables the first output matching network to simultaneously function as a quarter-wavelength impedance transformation line to achieve a 90-degree phase shift. At the same time, the carrier input matching network includes a phase compensation network to ensure that the combined power of the carrier power amplifier and the peak power amplifier is the largest when the output power is high, so that the power added efficiency of the Doherty radio frequency power amplifier of the present invention is high. In addition, the above-mentioned circuit replaces the quarter-wavelength impedance transformation line of the related art, so that the layout area of the Doherty radio frequency power amplifier is small.

Description of drawings

Below in conjunction with accompanying drawing, describe the utility model in detail. Through the detailed description in conjunction with the following drawings, the content of the above or other aspects of the present invention will become clearer and easier to understand. In the attached picture,

Fig. 1 is the schematic diagram of the circuit structure of the Doherty radio frequency power amplifier of related art;

Fig. 2 is the schematic diagram of the circuit structure of the utility model Doherty radio frequency power amplifier;

Fig. 3 is the application circuit structural representation of a kind of embodiment of Doherty radio frequency power amplifier of the present invention;

Fig. 4 is the circuit diagram of the Qualcomm T-type network of the utility model Doherty radio frequency power amplifier;

Fig. 5 is the circuit diagram of the low-pass T-type network of Doherty radio frequency power amplifier of the present invention;

Fig. 6 is the circuit diagram of the Qualcomm π-type network of the utility model Doherty radio frequency power amplifier;

Fig. 7 is the circuit diagram of the low-pass π-type network of Doherty radio frequency power amplifier of the present invention;

Fig. 8 is the application circuit structure diagram of another embodiment of the Doherty radio frequency power amplifier that the utility model embodiment provides;

Fig. 9 is a schematic diagram comparing the amplitude gain curves of the Doherty radio frequency power amplifier provided by the embodiment of the present invention and the Class AB radio frequency power amplifier of the related art.

Detailed ways

The specific embodiment of the utility model will be described in detail below in conjunction with the accompanying drawings.

The specific implementations/embodiments described here are specific specific implementations of the present utility model, and are used to illustrate the concept of the present utility model. Limitations on the scope of utility models. In addition to the embodiments described here, those skilled in the art can also adopt other obvious technical solutions based on the claims of the application and the contents disclosed in the description, and these technical solutions include adopting any obvious changes made to the embodiments described here. The replacement and modified technical solutions are all within the protection scope of the present utility model.

(Embodiment 1)

The embodiment of the utility model provides a Doherty radio frequency power amplifier 100 .

Please refer to shown in Fig. 2-3 at the same time, wherein, Fig. 2 is the application circuit structure diagram of Doherty radio frequency power amplifier 100 of the present invention; Fig. 3 is the application circuit structure diagram of a kind of embodiment of Doherty radio frequency power amplifier 100 of the present invention .

The Doherty radio frequency power amplifier 100 of the present invention includes a driver amplifier 1 , a carrier input matching network 2 , a carrier power amplifier 3 , a peak input matching network 4 , a peak power amplifier 5 , a first output matching network 6 and a second output matching network 7 .

The drive amplifier 1 is used to amplify external input signals.

The carrier input matching network 2 is used to realize 90-degree phase shift and input impedance matching.

The carrier power amplifier 3 is used to realize signal power amplification.

The peak input matching network 4 is used for input impedance matching.

The peak power amplifier 5 is used to realize signal power amplification.

The first output matching network 6 is used to realize 90-degree phase shift and output impedance matching.

The second output matching network 7 is used for output impedance matching.

Wherein, the specific circuit structure of the utility model Doherty radio frequency power amplifier 100 is:

The input terminal of the driving amplifier 1 is used as the input terminal RFin of the Doherty RF power amplifier 100 .

The output terminal of the driving amplifier 1 is respectively connected to the input terminal of the carrier input matching network 2 and the input terminal of the peak input matching network 4 .

The output end of the carrier input matching network 2 is connected to the input end of the carrier power amplifier 3 .

The output terminal of the carrier power amplifier 3 is connected to the input terminal of the first output matching network 6 .

The output end of the peak input matching network 4 is connected to the input end of the peak power amplifier 5 .

The output terminal of the peak power amplifier 5 is respectively connected to the input terminal of the second output matching network 7 and the output terminal of the first output matching network 6 .

The output terminal of the second output matching network 7 is used as the output terminal RFout of the Doherty radio frequency power amplifier 100 for connecting to the system load R.

In the above structure, the carrier input matching network 2 is arranged in front of the input end of the carrier power amplifier 3 , and the peak input matching network 4 is arranged in front of the input end of the peak power amplifier 5 . This setting enables uniform or non-uniform power distribution of the input power through the impedance value of the carrier input matching network 2 and the impedance value of the peak input matching network 4, thereby replacing the larger power divider in the related art, Therefore, the layout area of the Doherty radio frequency power amplifier 100 is small, and it is easy to be integrated on a chip of GaAs HBT process.

Wherein, the carrier input matching network 2 and the first output matching network 6 both include a phase compensation network for 90-degree phase shift and impedance transformation. This structure enables the first output matching network to simultaneously function as a quarter-wavelength impedance transformation line to achieve a 90-degree phase shift. At the same time, the carrier input matching network includes a phase compensation network to ensure that the combined power of the carrier power amplifier and the peak power amplifier is the largest when the output power is high. Therefore, the power added efficiency of the Doherty radio frequency power amplifier of the present invention is high. In addition, the above-mentioned circuit replaces the quarter-wavelength impedance transformation line of the related art, so that the layout area of the Doherty RF power amplifier 100 is small, and it is easy to be integrated on a chip of GaAs HBT process.

In this embodiment, the phase compensation network is any one of a high-pass T-type network, a high-pass π-type network, a low-pass T-type network, and a low-pass π-type network.

Wherein, the Qualcomm T-type network and the search Qualcomm π-type network realize a phase shift of +90 degrees. The low-pass T-network and the low-pass π-network implement a phase shift of -90 degrees.

Please refer to FIG. 4 . FIG. 4 is a circuit diagram of a Qualcomm T-shaped network of a Doherty radio frequency power amplifier of the present invention.

The Qualcomm T-type network includes a capacitor CA1, a capacitor CA2 and an inductor LA. Wherein, the capacitor CA1 and the capacitor CA2 are sequentially connected in series from the input end of the Qualcomm T-type network to the output end of the Qualcomm T-type network, and the inductance LA is connected across the capacitor CA1 and the capacitor Between the endpoints between CA2 and ground.

Please refer to FIG. 5, which is a circuit diagram of the low-pass T-shaped network of the Doherty radio frequency power amplifier of the present invention.

The low-pass T-type network includes an inductor LB1, an inductor LB2, and a capacitor CB. Wherein, the inductance LB1 and the inductance LB2 are sequentially connected in series from the input end of the low-pass T-type network to the output end of the low-pass T-type network, and the capacitor CB is connected across the inductance LB1 and the inductance LB1. Between the terminals between the inductor LB2 and the ground.

Please refer to FIG. 6, which is a circuit diagram of a high-pass π-type network of the Doherty radio frequency power amplifier of the present invention.

The Qualcomm π-type network includes an inductor LC1, an inductor LC2, and a capacitor CC. Wherein, the capacitor CC is set between the input end of the high-pass π-type network and the output end of the high-pass π-type network, and the inductor LC1 is connected between the input end of the high-pass π-type network and ground , the inductor LC2 is connected between the output terminal of the high-pass π-type network and the ground.

Please refer to FIG. 7 , which is a circuit diagram of a low-pass π-type network of a Doherty radio frequency power amplifier of the present invention.

The low-pass π-type network includes an inductor LD, a capacitor CD1 and a capacitor CD2. Wherein, the inductor LD is set between the input end of the low-pass π-type network and the output end of the low-pass π-type network, and the capacitor CD1 is connected across the input end of the low-pass π-type network and Between the ground, the capacitor CD2 is connected between the output terminal of the low-pass π-type network and the ground.

In practical applications, the type of matching network is selected according to the input and output impedance characteristics of the carrier power amplifier 3 and the peak power amplifier 5 . The carrier input matching network 2 is a Qualcomm T-type network or a Qualcomm π-type network. The first output matching network 6 is a low-pass T-type network or a low-pass π-type network. In the first embodiment, the carrier input matching network 2 is a high-pass T-type network, so as to suppress low-frequency clutter signal interference. The first output matching network 6 is a low-pass π-type network to suppress high-order harmonics.

In the first embodiment, the carrier input matching network 2 , the peak input matching network 4 , the first output matching network 6 and the second output matching network 7 are all lumped parameter circuits. The lumped parameter circuit is divided by the size of the circuit electrical device and the wavelength of the working signal. The actual circuit can be divided into a distributed parameter circuit and a lumped parameter circuit. A circuit that satisfies the d<<λ condition is called a lumped parameter circuit. Its characteristic is that the voltage between any two terminals in the circuit and the current flowing into any device port are completely determined, regardless of the geometric size and spatial position of the device. A circuit that does not satisfy the d<<λ condition is called a distributed parameter circuit. Its characteristic is that the voltage and current in the circuit are a function of time and are related to the geometric size and spatial position of the device. The use of lumped parameter circuits facilitates implementation using MMIC technology. Thereby the utility model Doherty radio frequency power amplifier 100 is easy to be integrated on the chip of a GaAs HBT process.

(Example 2)

Embodiment 2 provides a Doherty radio frequency power amplifier 200 . Please refer to FIG. 8 , which is a schematic structural diagram of an application circuit of another embodiment of a Doherty radio frequency power amplifier provided by an embodiment of the present invention.

The Doherty radio frequency power amplifier 200 provides a specific circuit for the circuit integration of the Doherty radio frequency power amplifier 100 . Therefore, the Doherty radio frequency power amplifier 200 is a specific technical solution with a small layout area and high power added efficiency. Wherein, in the second embodiment, the driving amplifier 1, the carrier power amplifier 3 and the peak power amplifier 5 are all realized by transistors.

The concrete circuit structure of Doherty RF power amplifier 101 is:

The driving amplifier 1 includes a first inductor L1, a second inductor L2, a first capacitor C1, a first transistor Q1 and a first bias circuit M1. The first terminal of the first capacitor C1 is used as the input terminal of the driving amplifier 1, and the first terminal of the first capacitor C1 is connected to the ground GND after being connected in series with the first inductor L1. The second terminal of the first capacitor C1 is respectively connected to the base of the first transistor Q1 and the output terminal of the first bias circuit M1. The emitter of the first transistor Q1 is connected to the ground GND. The collector of the first transistor Q1 is used as the output terminal of the driving amplifier 1, and the collector of the first transistor Q1 is respectively connected to the second end of the second inductor L2, the carrier input matching network 2 The input terminal of and the input terminal of the peak input matching network 4. The first terminal of the second inductor L2 is connected to the power supply voltage Vcc. The input terminal of the first bias circuit M1 is connected to the reference voltage Vreg.

The carrier input matching network 2 includes a third inductor L3, a second capacitor C2 and a third capacitor C3. The first terminal of the second capacitor C2 is used as the input terminal of the carrier input matching network 2, and the first terminal of the second capacitor C2 is connected to the collector of the first transistor Q1. The second terminal of the second capacitor C2 is respectively connected to the first terminal of the third capacitor C3 and the first terminal of the third inductor L3. The second end of the third inductor L3 is connected to the ground GND. The second terminal of the third capacitor C3 is used as the output terminal of the carrier input matching network 2 .

The carrier power amplifier 3 includes a second bias circuit M2 and a second transistor Q2. The base of the second transistor Q2 is used as the input end of the carrier power amplifier 3, and the base of the second transistor Q2 is respectively connected to the second end of the third capacitor C3 and the second bias output of circuit M2. The emitter of the second transistor Q2 is connected to the ground GND. The collector of the second transistor Q2 serves as the output terminal of the carrier power amplifier 3 . The input terminal of the second bias circuit M2 is connected to the reference voltage Vreg.

The peak input matching network 4 includes a fourth capacitor C4. The first terminal of the fourth capacitor C4 is used as the input terminal of the peak input matching network 4, and the first terminal of the fourth capacitor C4 is connected to the collector of the first transistor Q1. The second terminal of the fourth capacitor C4 is used as the output terminal of the peak input matching network 4 .

The peak power amplifier 5 includes a third bias circuit M3 and a third transistor Q3. The base of the third transistor Q3 is used as the input terminal of the peak power amplifier 5, and the base of the third transistor Q3 is connected to the second terminal of the fourth capacitor C4 and the third bias circuit output of M3. The emitter of the third transistor Q3 is connected to the ground GND. The collector of the third transistor Q3 is used as the output terminal of the peak power amplifier 5 . The input end of the third bias circuit M3 is connected to the reference voltage Vreg.

The first output matching network 6 includes a fifth capacitor C5, a sixth capacitor C6 and a fourth inductor L4. The first end of the fourth inductor L4 is used as the input end of the first output matching network 6, and the first end of the fourth inductor L4 is respectively connected to the collector of the second transistor Q2 and the second transistor Q2. The first terminal of five capacitors C5. The second terminal of the fourth inductor L4 is used as the output terminal of the peak power amplifier 5, and the second terminal of the fourth inductor L4 is connected to the first terminal of the sixth capacitor C6. The second terminal of the fifth capacitor C5 is connected to the ground GND. The second terminal of the sixth capacitor C6 is connected to the ground GND.

The second output matching network 7 includes a fifth inductor L5, a sixth inductor L6, a seventh inductor L7, a seventh capacitor C7 and an eighth capacitor C8. The first terminal of the fifth inductor L5 is used as the input terminal of the second output matching network 7, and the first terminal of the fifth inductor L5 is respectively connected to the collector of the third transistor Q3 and the first terminal of the second transistor Q3. The second terminal of the six inductors L6. A first end of the sixth inductor L6 is connected to the power supply voltage Vcc. The second terminal of the fifth inductor L5 is respectively connected to the first terminal of the seventh capacitor C7 and the first terminal of the eighth capacitor C8. The second end of the seventh capacitor C7 is connected to the ground GND. The second end of the eighth capacitor C8 is used as the output end of the second output matching network 7, and the second end of the eighth capacitor C8 is connected to the first end of the seventh inductor L7. The second end of the seventh inductor L7 is connected to the ground GND.

From the above circuit structure, it can be seen that both the carrier input matching network 2 and the first output matching network 6 include a phase compensation network for 90-degree phase shift and impedance transformation. This structure enables the first output matching network to simultaneously function as a quarter-wavelength impedance transformation line to achieve a 90-degree phase shift. At the same time, the carrier input matching network includes a phase compensation network to ensure that the combined power of the carrier power amplifier and the peak power amplifier is the largest when the output power is high. Therefore, the power added efficiency of the Doherty radio frequency power amplifier of the present invention is high. In addition, the above-mentioned circuit replaces the quarter-wavelength impedance transformation line of the related art, so that the layout area of the Doherty RF power amplifier 100 is small, and it is easy to be integrated on a chip of GaAs HBT process.

Please refer to FIG. 9, which is a schematic diagram of the comparison of the amplitude gain curves of the Doherty radio frequency power amplifier provided by the embodiment of the present invention and the Class AB radio frequency power amplifier of the related art.

It can be seen from the picture: when the power backs off by 8dB, the efficiency of the Doherty RF power amplifier 200 is 18% higher than that of the Class AB RF power amplifier of the related technology.

Therefore, the Doherty radio frequency power amplifier 200 has fewer circuit components, high circuit performance, and is easy to be integrated on a GaAs HBT process chip.

It should be noted that the various embodiments described above with reference to the accompanying drawings are only used to illustrate the utility model rather than limit the scope of the utility model, those of ordinary skill in the art should understand that without departing from the spirit and scope of the utility model Any modifications or equivalent replacements made to the present utility model under the premise of the present utility model shall be covered within the scope of the present utility model. Further, words appearing in the singular include the plural and vice versa unless the context otherwise requires. Additionally, all or a portion of any embodiment may be utilized with all or a portion of any other embodiment, unless stated otherwise.

Claims

A kind of Doherty radio frequency power amplifier, it is characterized in that, it comprises driver amplifier, carrier input matching network, carrier power amplifier, peak input matching network, peak power amplifier, first output matching network and second output matching network;

The input end of described driving amplifier is used as the input end of described Doherty radio frequency power amplifier;

The output end of the drive amplifier is respectively connected to the input end of the carrier input matching network and the input end of the peak input matching network;

The output terminal of the carrier input matching network is connected to the input terminal of the carrier power amplifier;

The output terminal of the carrier power amplifier is connected to the input terminal of the first output matching network;

The output terminal of the peak input matching network is connected to the input terminal of the peak power amplifier;

The output end of the peak power amplifier is respectively connected to the input end of the second output matching network and the output end of the first output matching network;

The output end of the second output matching network is used as the output end of the Doherty radio frequency power amplifier for connecting the system load;

Wherein, both the carrier input matching network and the first output matching network include a phase compensation network for 90-degree phase shift and impedance transformation;

The phase compensation network is any one of a high-pass T-type network, a high-pass π-type network, a low-pass T-type network and a low-pass π-type network.
The Doherty RF power amplifier according to claim 1, wherein the carrier input matching network is a high-pass T-type network or a high-pass π-type network; the first output matching network is a low-pass T-type network or a low-pass π-type network type network.
The Doherty radio frequency power amplifier according to claim 2, wherein the carrier input matching network is a high-pass T-type network; the first output matching network is a low-pass π-type network.
Doherty radio frequency power amplifier according to claim 3, is characterized in that, described driver amplifier, described carrier power amplifier and described peak power amplifier all adopt transistor to realize.
Doherty radio frequency power amplifier according to claim 4, is characterized in that,

The carrier input matching network includes a third inductor, a second capacitor, and a third capacitor; the first end of the second capacitor is used as an input end of the carrier input matching network, and the first end of the second capacitor is connected to to the collector of the first transistor; the second end of the second capacitor is respectively connected to the first end of the third capacitor and the first end of the third inductor; the second end of the third inductor The terminal is connected to ground; the second terminal of the third capacitor is used as the output terminal of the carrier input matching network;

The first output matching network includes a fifth capacitor, a sixth capacitor, and a fourth inductor; the first end of the fourth inductor serves as an input end of the first output matching network, and the first end of the fourth inductor terminals are respectively connected to the collector of the second transistor and the first terminal of the fifth capacitor; the second terminal of the fourth inductance is used as the output terminal of the peak power amplifier, and the first terminal of the fourth inductance The two terminals are connected to the first terminal of the sixth capacitor; the second terminal of the fifth capacitor is connected to the ground; the second terminal of the sixth capacitor is connected to the ground.
The Doherty radio frequency power amplifier according to claim 5, wherein the driving amplifier comprises a first inductance, a second inductance, a first capacitor, a first transistor and a first bias circuit; the first capacitor of the first capacitor One end is used as the input end of the driving amplifier, and the first end of the first capacitor is connected to ground after being connected in series with the first inductor, and the second end of the first capacitor is respectively connected to the first transistor The base of the first bias circuit and the output terminal of the first bias circuit, the emitter of the first transistor is connected to the ground, the collector of the first transistor is used as the output terminal of the driving amplifier, and the first transistor’s The collector is respectively connected to the second end of the second inductor, the input end of the carrier input matching network and the input end of the peak input matching network; the first end of the second inductor is connected to the power supply voltage; The input end of the first bias circuit is connected to the reference voltage.
The Doherty radio frequency power amplifier according to claim 5, wherein the carrier power amplifier includes a second bias circuit and a second transistor; the base of the second transistor is used as the input terminal of the carrier power amplifier, And the base of the second transistor is respectively connected to the second end of the third capacitor and the output end of the second bias circuit; the emitter of the second transistor is connected to ground; the second transistor The collector of the carrier power amplifier is used as the output terminal of the carrier power amplifier; the input terminal of the second bias circuit is connected to the reference voltage.
The Doherty radio frequency power amplifier according to claim 5, wherein the peak input matching network includes a fourth capacitor; the first end of the fourth capacitor is used as the input of the peak input matching network, and the The first end of the fourth capacitor is connected to the collector of the first transistor; the second end of the fourth capacitor is used as the output end of the peak input matching network;

The peak power amplifier includes a third bias circuit and a third transistor; the base of the third transistor is used as the input of the peak power amplifier, and the base of the third transistor is connected to the fourth capacitor The second terminal of the second terminal and the output terminal of the third bias circuit; the emitter of the third transistor is connected to the ground; the collector of the third transistor is used as the output terminal of the peak power amplifier; the third The input terminal of the bias circuit is connected to a reference voltage.
Doherty radio frequency power amplifier according to claim 5, is characterized in that, described second output matching network comprises the 5th inductance, the 6th inductance, the 7th inductance, the 7th electric capacity and the 8th electric capacity; The first end is used as the input end of the second output matching network, and the first end of the fifth inductor is respectively connected to the collector of the third transistor and the second end of the sixth inductor; The first end of the six inductors is connected to the power supply voltage; the second end of the fifth inductor is respectively connected to the first end of the seventh capacitor and the first end of the eighth capacitor; the first end of the seventh capacitor The two ends are connected to ground; the second end of the eighth capacitor is used as the output end of the second output matching network, and the second end of the eighth capacitor is connected to the first end of the seventh inductor; The second end of the seventh inductor is connected to ground.
The Doherty RF power amplifier according to claim 1, wherein the carrier input matching network, the peak input matching network, the first output matching network and the second output matching network are lumped parameters circuit.