WO2023082933A1 - 射频功率放大器 - Google Patents

射频功率放大器 Download PDF

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Publication number
WO2023082933A1
WO2023082933A1 PCT/CN2022/125267 CN2022125267W WO2023082933A1 WO 2023082933 A1 WO2023082933 A1 WO 2023082933A1 CN 2022125267 W CN2022125267 W CN 2022125267W WO 2023082933 A1 WO2023082933 A1 WO 2023082933A1
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Prior art keywords
transistor
power amplifier
collector
base
capacitor
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PCT/CN2022/125267
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English (en)
French (fr)
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谢志远
赵宇霆
郭嘉帅
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深圳飞骧科技股份有限公司
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Publication of WO2023082933A1 publication Critical patent/WO2023082933A1/zh

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    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
    • H03F1/30—Modifications of amplifiers to reduce influence of variations of temperature or supply voltage or other physical parameters
    • H03F1/301—Modifications of amplifiers to reduce influence of variations of temperature or supply voltage or other physical parameters in MOSFET amplifiers
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/189—High-frequency amplifiers, e.g. radio frequency amplifiers
    • H03F3/19—High-frequency amplifiers, e.g. radio frequency amplifiers with semiconductor devices only
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/20—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers
    • H03F3/21—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers with semiconductor devices only
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/45—Differential amplifiers
    • H03F3/45071—Differential amplifiers with semiconductor devices only
    • H03F3/45479—Differential amplifiers with semiconductor devices only characterised by the way of common mode signal rejection
    • H03F3/45484—Differential amplifiers with semiconductor devices only characterised by the way of common mode signal rejection in differential amplifiers with bipolar transistors as the active amplifying circuit
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F2200/00—Indexing scheme relating to amplifiers
    • H03F2200/447—Indexing scheme relating to amplifiers the amplifier being protected to temperature influence
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F2200/00—Indexing scheme relating to amplifiers
    • H03F2200/451—Indexing scheme relating to amplifiers the amplifier being a radio frequency amplifier

Definitions

  • the invention relates to the technical field of radio frequency identification, in particular to a radio frequency power amplifier applied to a mobile communication device.
  • Radio frequency identification technology is a key technology for the Internet of Things.
  • the RF front-end module includes a low-noise amplifier (LNA), a power amplifier (PA), a filter, a switch, an antenna, etc.
  • the power amplifier is a very important module for the RF front-end. group, its function is: to amplify the output signal, and send out the amplified signal by the antenna.
  • the key module of the 5G wireless communication system is the RF power amplifier (Power Amplifier, RF) located at the final stage of the transmitter. Its PA directly affects and determines the output power, efficiency, gain, linearity, operating bandwidth, reflection coefficient, etc. of the transmitter system.
  • RF Power Amplifier
  • the performance indicators of the entire 5G wireless communication system will affect and determine the performance indicators of the entire 5G wireless communication system.
  • the 5G frequency band is divided into two major ranges, namely 450MHz-6GHz (Sub6G for short) and 24.25GHz-52.6GHz (millimeter wave frequency band).
  • the higher the frequency the shorter the signal propagation distance, so the coverage radius of the base station is small.
  • the N79 frequency band is relatively lower in frequency than the millimeter wave, and has a wider bandwidth. Therefore, it is particularly important to propose a radio frequency power amplifier that works in the N77 frequency band in Sub6G.
  • a radio frequency power amplifier in the prior art includes a bias circuit, an input and output matching network, a transistor, and the like.
  • the requirements for the bias circuit are often high.
  • Figure 1 it is a schematic diagram of a radio frequency power amplifier circuit in the prior art.
  • RF in is a signal input port
  • RF out is a signal output port
  • V bat and V cc are power supplies
  • I 1 For the bias current of the bias circuit
  • Q0 is the transistor.
  • the bias circuit is an important part of the RF power amplifier. It provides a DC bias point for the amplifier. The bias point will directly affect the power gain, efficiency and linearity of the output power of the RF power amplifier.
  • the stability of the bias circuit directly Determines the stability of functional modules. That is, the role of the bias circuit is to provide a stable and suitable quiescent operating point for the RF power amplifier under a given situation, and to ensure the stability of its working state, while suppressing the influence of transistor parameters with temperature changes.
  • RF power amplifiers that support 5G mobile communications. 5G networks require power amplifiers to provide greater power, and the thermal effect of transistors will increase dramatically. In 5G mobile communication, the N77 frequency band is 3.3GHz-4.2GHz. Because of its high frequency, there are higher requirements for the output power of the RF power amplifier. In the case of higher output power, the self-heating effect of the transistor will be more significant. Now State-of-the-art biasing circuits are no longer suitable for RF power amplifiers.
  • the present invention proposes a radio frequency power amplifier that is applied in 5G mobile communications, has a good effect on suppressing the thermal effect of transistors, provides better quiescent current stability, and has high output power and good consistency.
  • the present invention provides a radio frequency power amplifier, including an input terminal, an output terminal, a first transistor and a bias circuit; the base of the first transistor is connected to the input terminal, and the first The emitter of the transistor is grounded, the collector of the first transistor is connected to the output terminal, and the bias circuit is connected between the base of the first transistor and the input terminal;
  • the bias circuit includes: a second transistor, a third transistor, a fourth transistor, a first capacitor, a second capacitor, and a thermal effect suppression resistor;
  • the base of the third transistor is connected to the collector of the third transistor, the collector of the third transistor is connected to a reference voltage source, and the emitter of the third transistor is connected to the collector of the second transistor electrode;
  • the base of the second transistor is connected to the collector of the second transistor, and the emitter of the second transistor is grounded;
  • the base of the fourth transistor is connected to the base of the third transistor, the collector of the fourth transistor is connected to a supply voltage source, and the emitter of the fourth transistor is connected to to the base of the first transistor;
  • the first end of the first capacitor is connected to the emitter of the fourth transistor, and the second end of the first capacitor is connected to ground;
  • a first terminal of the second capacitor is connected to the base of the fourth transistor, and a second terminal of the second capacitor is connected to the collector of the first transistor.
  • the bias circuit further includes a first resistor and a second resistor, the collector of the third transistor is connected to the reference voltage source after being connected in series with the second resistor, and the emitter of the second transistor is connected in series ground after the first resistor.
  • the bias circuit further includes a third resistor connected in series between the base of the fourth transistor and the first end of the second capacitor.
  • the RF power amplifier further includes an input matching network connected in series between the input terminal and the base of the first transistor.
  • the input matching network is composed of capacitors.
  • the radio frequency power amplifier further includes an output matching network, and the output matching network is connected between the collector of the first transistor and the output terminal.
  • the output matching network is composed of an inductor and a third capacitor; one end of the inductor is connected to the collector of the first transistor, and the other end of the inductor is connected to a circuit voltage source; the third capacitor is connected in series between the collector of the first transistor and the output terminal.
  • the radio frequency power amplifier of the present invention designs the bias circuit, has a simple structure, and supports the working frequency band (ie high-frequency signal) of the 5G network.
  • the bias circuit is designed due to the first capacitance And the existence of the second capacitor, the part of the high-frequency signal with a lower frequency in the working frequency band is first filtered to the ground by the first capacitor to filter out the high-frequency signal with a lower frequency in the working frequency band, while the other part of the working frequency band
  • the high-frequency signal with higher frequency passes through the emitter of the fourth transistor, the base of the fourth transistor, and the second capacitor to the collector of the first transistor in sequence to form a feedback structure, which can convert the leaked operating frequency band
  • the higher high-frequency signal is added to the output signal, so the high-frequency output power of the RF power amplifier in the working frequency band is effectively improved, and the base potential of the fourth transistor remains unchanged, so the linearity of the RF power amplifier is effectively improved.
  • the bias resistor can effectively suppress the self-heating effect of the transistor, effectively improve the stability of the bias circuit, and provide a stable quiescent current, so that the transistor can always work at a stable quiescent operating point, thereby ensuring the gain of the power amplifier, Stability of output power and output power linearity.
  • Fig. 1 is the circuit schematic diagram of the radio frequency power amplifier of prior art
  • Fig. 2 is the circuit diagram of the radio frequency power amplifier of prior art
  • Fig. 3 is a schematic diagram of the movement of the bias point in Fig. 2;
  • FIG. 4 is a circuit diagram of a radio frequency power amplifier according to an embodiment of the present invention.
  • Fig. 5 is the circuit diagram of the radio frequency power amplifier of embodiment 2 of the present invention.
  • FIG. 6 is a simulation effect diagram of output power and power-added efficiency obtained by the bias circuit of the radio frequency power amplifier in the prior art in FIG. 2;
  • Fig. 7 is a simulation effect diagram of output power and power added efficiency obtained by the bias circuit of the radio frequency power amplifier of the present invention.
  • FIG. 2 is a circuit diagram of a radio frequency power amplifier in the prior art and a schematic diagram of bias point movement thereof;
  • FIG. 3 is a schematic diagram of bias point movement in FIG. 2 .
  • RF in is a signal input port
  • RF out is a signal output port
  • Q 0 is a transistor
  • R1 and R2 are voltage dividing resistors. That is, the bias circuit of the radio frequency power amplifier in the prior art is composed of two voltage dividing resistors connected in series.
  • the present invention overcomes the above-mentioned problems by improving the bias circuit.
  • Embodiment 1 of the present invention provides a radio frequency power amplifier 100 , which includes an input terminal RF in , an output terminal RF out , a first transistor Q 0 and a bias circuit 10 .
  • the base of the first transistor Q 0 is connected to the input terminal RF in , the emitter of the first transistor Q 0 is grounded, and the collector of the first transistor Q 0 is connected to the output terminal RF out ,
  • the bias circuit 10 is connected between the base of the first transistor Q0 and the input terminal RF in .
  • the bias circuit 10 includes: a second transistor Q 1 , a third transistor Q 2 , a fourth transistor Q 3 , a first capacitor CL1 , a second capacitor CL2 , and a thermal effect suppression resistor R bias .
  • both the first capacitor C L1 and the second capacitor C L2 are filter capacitors.
  • the base of the third transistor Q 2 is connected to the collector of the third transistor Q 2 , the collector of the third transistor Q 2 is connected to the reference voltage source V reg , the emitter of the third transistor Q 2 The pole is connected to the collector of the second transistor Q1 .
  • the base of the second transistor Q1 is connected to the collector of the second transistor Q1 , and the emitter of the second transistor Q1 is grounded.
  • the base of the fourth transistor Q3 is connected to the base of the third transistor Q2 , the collector of the fourth transistor Q3 is connected to the supply voltage source Vbat , and the emitter of the fourth transistor Q3 The pole is connected to the base of the first transistor Q0 through the series connection of the thermal effect suppressing resistor Rbias .
  • a first end of the first capacitor C L1 is connected to the emitter of the fourth transistor Q3 , and a second end of the first capacitor C L1 is connected to ground.
  • a first terminal of the second capacitor CL2 is connected to the base of the fourth transistor Q3 , and a second terminal of the second capacitor CL2 is connected to the collector of the first transistor Q0 .
  • the bias circuit 10 further includes a first resistor R 1 and a second resistor R 2 , and the collector of the third transistor Q 2 is connected in series with the second resistor R 2 is then connected to the reference voltage source V reg , and the emitter of the second transistor Q 1 is connected in series with the first resistor R 1 and grounded.
  • the RF power amplifier 100 further includes an input matching network connected in series between the input terminal RF in and the base of the first transistor Q 0 .
  • the input matching network is composed of a capacitor C.
  • the RF power amplifier 100 further includes an output matching network, and the output matching network is connected between the collector of the first transistor Q0 and the output terminal RF out .
  • the output matching network is composed of an inductor L and a third capacitor C3 ; one end of the inductor L is connected to the collector of the first transistor Q0 , and the other end of the inductor L connected to the circuit voltage source V cc ; the third capacitor C 3 is connected in series between the collector of the first transistor Q 0 and the output terminal RF out .
  • the second transistor Q 1 and the third transistor Q 2 form a clamping voltage, so that the current I 2 is a stable current, and the magnitude of the current I 2 can be adjusted by adjusting the first resistor R 1 and the second resistor R 2 .
  • the DC current of the first transistor Q0 increases, and due to the self-heating effect of the transistor and the rectification characteristics of the diode, the base potential V b0 of the first transistor Q0 will drop, The signal on the radio frequency line leaks into the bias circuit 10 . Due to the existence of the first capacitor CL1 and the second capacitor CL2 , part of the high-frequency signal first passes through the first capacitor CL1 to the ground, and the other part of the high-frequency signal passes through the emitter stage of the fourth transistor Q3 and the fourth transistor Q3 in turn.
  • the base stage of the fourth transistor Q3 and the emitter stage are due to the rectification effect, and the voltage Vbe3 between the base stage and the emitter stage decreases, because the base stage potential of the four transistors Q3 remains unchanged, so the base stage of the first transistor Q0
  • the reduction of the electrode voltage V b0 is effectively compensated, so that the first transistor Q 0 maintains a static operating point in a state of high input and output power, so that the gain compression is effectively suppressed.
  • the bias resistor R bias can effectively suppress the self-heating effect of the first transistor Q0 , thereby effectively improving the stability of the bias circuit 10, which can provide a stable quiescent current, so that the first transistor Q0 can be kept It has been working at a stable static operating point to ensure the stability of the gain, output power and output power linearity of the power amplifier.
  • the bias circuit 10 of the present invention with the above structure forms an active bias circuit with temperature compensation.
  • the output power in the working frequency band is basically consistent, and has a better improvement effect on the technical problems raised by the present invention.
  • bias resistance R bias within a certain range can effectively improve the stability of the static operating point of the radio frequency power amplifier 100, but beyond this range, if the bias resistance R bias continues to increase, the radio frequency Nonlinearity of power amplifier 100 when large signal input.
  • Increasing the size of the bias resistor R bias increases the linearity of the output power by first increasing and then decreasing.
  • the size of the bias resistor R bias needs to be selected in combination with the working requirements of the radio frequency power amplifier 100.
  • the size of the resistor R bias is generally a compromise between natural effects and linearity.
  • Fig. 6 is the output power and the power added efficiency emulation effect drawing that the bias circuit of the radio frequency power amplifier of prior art obtains in Fig. 2;
  • Fig. 7 is the bias circuit of radio frequency power amplifier of the present invention The obtained output power and power-added efficiency simulation renderings.
  • the 1dB power compression point of the radio frequency power amplifier circuit in the prior art is 36.5dBm.
  • the 1dB power compression point of the circuit of the radio frequency power amplifier of the present invention is 38dBm. Comparing the simulation results, it can be seen that the high-frequency output power of the RF power amplifier is significantly improved by using the bias circuit of the present invention.
  • the traditional bias circuit of the prior art is improved, and the structure is simple and easy to realize;
  • the bias circuit in the present invention has a good improvement on the thermal effect of the transistor in the radio frequency power amplifier, and can provide stable current, At the same time, it can also compensate the high-frequency output power of the radio frequency power amplifier, so as to achieve the purpose of consistent output power of low frequency, intermediate frequency and high frequency.
  • FIG. 5 is a circuit diagram of a radio frequency power amplifier according to Embodiment 2 of the present invention.
  • This embodiment is basically the same as the embodiment shown in FIG. 4 above, except that the bias circuit 100 further includes a third resistor R 3 , and the third resistor R 3 is connected in series with the base of the fourth transistor Q 3 and the first terminal of the second capacitor C L2 .
  • the third resistor R3 can adjust the feedback depth, and the value of the third resistor R3 and the first capacitor C L1 can be adjusted to increase the stability of the circuit (stability coefficient K value), and the base potential Vb3 of the fourth transistor Q3 maintains Therefore, the linearity of the radio frequency power amplifier 100 is further effectively improved.
  • the radio frequency power amplifier of the present invention designs the bias circuit, has a simple structure, and supports the working frequency band (ie high-frequency signal) of the 5G network.
  • the bias circuit is designed due to the first capacitance And the existence of the second capacitor, the part of the high-frequency signal with a lower frequency in the working frequency band is first filtered to the ground by the first capacitor to filter out the high-frequency signal with a lower frequency in the working frequency band, while the other part of the working frequency band
  • the high-frequency signal with a higher frequency passes through the emitter of the fourth transistor, the base of the fourth transistor, and the second capacitor to the collector of the first transistor in sequence to form a feedback structure, which can convert the leaked operating frequency band
  • the higher high-frequency signal is added to the output signal, thus effectively improving the high-frequency output power of the RF power amplifier in the operating frequency band; and the base potential of the fourth transistor remains unchanged, so the linearity of the RF power amplifier is effectively improve.
  • the bias resistor can effectively suppress the self-heating effect of the transistor, effectively improve the stability of the bias circuit, and provide a stable quiescent current, so that the transistor can always work at a stable quiescent operating point, thereby ensuring the gain of the power amplifier, Stability of output power and output power linearity.

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Abstract

一种射频功率放大器(100)，包括偏置电路(10)，该偏置电路(10)中，第三晶体管(Q 2)的基极连接至第三晶体管(Q 2)的集电极，集电极连接至基准电压源(V reg)，发射极连接至第二晶体管(Q 1)的集电极；第二晶体管(Q 1)的基极连接至第二晶体管(Q 1)的集电极，发射极接地；第四晶体管(Q 3)的基极连接至第三晶体管(Q 2)的基极，集电极连接至供电电压源，发射极通过串联热效应抑制电阻(R bias)后连接至第一晶体管(Q 0)的基极；第一电容(C L1)的第一端连接至第四晶体管(Q 3)的发射极，第一电容(C L1)的第二端连接接地；第二电容(C L2)的第一端连接至第四晶体管(Q 3)的基极，第二电容(C L2)的第二端连接至第一晶体管(Q 0)的集电极。与相关技术相比，本射频功率放大器(100)中，其偏置电路(10)对晶体管热效抑制效果好且提供的静态电流稳定性更优，输出功率高且一致性好。

Description

射频功率放大器 技术领域
本发明涉及射频识别技术领域，尤其涉及一种运用于移动通讯装置的射频功率放大器。
背景技术
射频识别技术(RFID)为物联网万物互联的关键技术，射频前端模组包括低噪声放大器(LNA)、功率放大器(PA)、滤波器、开关、天线等，功率放大器是射频前端非常重要的模组，其作用为：将输出信号进行放大，由天线将被放大的信号发出。5G无线通信系统关键模块是位于发射机末级的射频功率放大器(Power Amplifier，RF)，其PA直接影响和决定发射机系统的输出功率、效率、增益、线性度、工作带宽、反射系数等各项性能指标，从而影响和决定整个5G无线通信系统的各项性能指标。5G频段分为两大范围，分别为450MHz～6GHz(简称Sub6G)和24.25GHz～52.6GHz(毫米波频段)。频率越高信号传播距离越短，因此基站覆盖半径较小，受到基站数量和高频信号传播的能量耗散等等问题，毫米波频段暂时不易实现5G通信系统广泛运用；其中N41、N77、N78、N79频段相对毫米波频率较低，且带宽较宽，因此，提出一种工作在Sub6G中N77频段的射频功率放大器尤为重要。
现有技术的射频功率放大器包括偏置电路、输入输出匹配网络、晶体管等。使用GaAs HBT工艺对射频功率放大器进行设计时，往往对偏置电路的要求较高。如图1所示，为现有技术的射频功率放大器电路原理图，其偏置电路模块中，RF in为信号输入端口，RF out为信号输出端口，V bat、V cc为供电电源，I 1为偏置电路的偏置电流，Q 0为晶体管。偏置电路是射频功率放大器的一个重要组成部分，为 放大器提供直流偏置点，该偏置点将直接影响射频功率放大器的功率增益、效率和输出功率的线性度，偏置电路的稳定性直接决定功能性模块的稳定性。即，偏置电路的作用是在给定情况下为射频功率放大器提供一个稳定且适合的静态工作点，并确保其工作状态的稳定性，同时抑制晶体管参数随温度变化而产生的影响。支持5G移动通信的射频功率放大器，5G网络需要功率放大器提供更大的功率，晶体管的热效应将会增加剧烈。5G移动通信中N77频段为3.3GHz-4.2GHz，因其频率较高，对射频功率放大器的输出功率有更高的要求，在输出更大功率的情况下，晶体管的自热效应将更加显著，现有技术的偏置电路对射频功率放大器将不再适用。
因此，实有必要提供一种新的射频功率放大器解决上述问题。
发明内容
针对以上现有技术的不足，本发明提出一种运用于5G移动通讯中，具有对晶体管热效抑制效果好且提供静态电流稳定性更优，输出功率高且一致性好的射频功率放大器。
为了解决上述技术问题，本发明提供了一种射频功率放大器，包括输入端、输出端，第一晶体管及偏置电路；所述第一晶体管的基极连接至所述输入端，所述第一晶体管的发射极接地，所述第一晶体管的集电极连接至所述输出端，所述偏置电路搭接至所述第一晶体管的基极与所述输入端之间；
所述偏置电路包括：第二晶体管、第三晶体管、第四晶体管、第一电容、第二电容、热效应抑制电阻；
所述第三晶体管的基极连接至所述第三晶体管的集电极，所述第三晶体管的集电极连接至基准电压源，所述第三晶体管的发射极连接至所述第二晶体管的集电极；
所述第二晶体管的基极连接至所述第二晶体管的集电极，所述第二晶体管的发射极接地；
所述第四晶体管的基极连接至所述第三晶体管的基极，所述第四晶体管的集电极连接至供电电压源，所述第四晶体管的发射极通过串联所述热效应抑制电阻后连接至所述第一晶体管的基极；
所述第一电容的第一端连接至所述第四晶体管的发射极，所述第一电容的第二端连接接地；
所述第二电容的第一端连接至所述第四晶体管的基极，所述第二电容的第二端连接至所述第一晶体管的集电极。
优选的，所述偏置电路还包括第一电阻和第二电阻，所述第三晶体管的集电极串联所述第二电阻后连接至所述基准电压源，所述第二晶体管的发射极串联所述第一电阻后接地。
优选的，所述偏置电路还包括第三电阻，所述第三电阻串联于所述第四晶体管的基极与所述第二电容的第一端之间。
优选的，所述射频功率放大器还包括串联至所述输入端与所述第一晶体管的基极之间的输入匹配网络。
优选的，所述输入匹配网络为电容构成。
优选的，所述射频功率放大器还包括输出匹配网络，所述输出匹配网络连接至所述第一晶体管的集电极和所述输出端之间。
优选的，所述输出匹配网络由电感和第三电容构成；所述电感的一端连接至所述第一晶体管的集电极，所述电感的另一端连接至电路电压源；所述第三电容串联至所述第一晶体管的集电极与所述输出端之间。
与相关技术相比，本发明的射频功率放大器对偏置电路进行设计，结构简单，支持5G网络的工作频段(即高频信号)，该5G工作频段中，偏置电路由于设计的第一电容和第二电容的存在，将工作频段内的频率较低的一部分高频信号先经过第一电容滤波至地，以滤除该工作频段内频率较低的高频信号，而另一部分工作频段内频率较高的高频信号则依次经过第四晶体管的发射极、第四晶体管的基极、第二电容至第一晶体管的集电极，形成反馈结构，该反馈结构可将泄露的工 作频段内频率较高的高频信号补充至输出信号中，因此有效提高了射频功率放大器在工作频段内的高频输出功率，且第四晶体管的基极电位保持不变，因此射频功率放大器的线性度得到有效提高。偏置电阻可有效的抑制晶体管的自热效应，有效提高偏置电路的稳定性，即可提供稳定的静态电流，因此可保持晶体管一直工作在稳定的静态工作点，以此确保功率放大器的增益、输出功率和输出功率线性度的稳定性。
附图说明
下面结合附图详细说明本发明。通过结合以下附图所作的详细描述，本发明的上述或其他方面的内容将变得更清楚和更容易理解。附图中：
图1为现有技术的射频功率放大器的电路原理图；
图2为现有技术的射频功率放大器的电路图；
图3为图2的偏置点移动示意图；
图4为本发明实施例一射频功率放大器的电路图；
图5为本发明实施例二射频功率放大器的电路图；
图6为图2中现有技术的射频功率放大器的偏置电路得到的输出功率和功率附加效率仿真效果图；
图7为本发明射频功率放大器的偏置电路得到的输出功率和功率附加效率仿真效果图。
具体实施方式
下面结合附图详细说明本发明的具体实施方式。
在此记载的具体实施方式/实施例为本发明的特定的具体实施方式，用于说明本发明的构思，均是解释性和示例性的，不应解释为对本发明实施方式及本发明范围的限制。除在此记载的实施例外，本领域技术人员还能够基于本申请权利要求书和说明书所公开的内容采用 显而易见的其它技术方案，这些技术方案包括采用对在此记载的实施例的做出任何显而易见的替换和修改的技术方案，都在本发明的保护范围之内。
以下各实施例的说明是参考附加的图式，用以例示本发明可用以实施的特定实施例。本发明所提到的方向用语，例如上、下、前、后、左、右、内、外、侧面等，仅是参考附加图式的方向。因此，使用的方向用语是用以说明及理解本发明，而非用以限制本发明。
请结合图2-3所示，其中，图2为现有技术的射频功率放大器的电路图及其偏置点移动示意图；图3为图2的偏置点移动示意图。图2中，现有技术的射频功率放大器的偏置电路模块中，RF in为信号输入端口，RF out为信号输出端口，Q 0为晶体管，R1、R2为分压电阻。即现有技术的射频功率放大器的偏执电路由两个分压电阻串联组成。结合图2-3所示，当输入大信号时，因二极管的钳位特性，Q 0的基-射结二极管上的正向电压和反向电流被限幅。经过基-射结二极管整流后的平均直流电流I rec将随输入功率增大而增大，由于晶体管自热效应，基-射结两端电压V be降低了ΔV be，偏置点从S移动至L 1，这将导致跨导、增益的减小和相位的失真。为补偿大信号条件下的增益压缩和相位失真，必须保持大信号跨导和小信号跨导一致。因此，应将偏置点L 1移动到L 2处。而在频段为N77(3.3GHz-4.2GHz)、N79(4.5GHz-5GHz)的功率放大器(PA)设计中，不可避免的都存在高频输出功率低于低频输出功率的问题。因此，本发明由对偏置电路进行改进，克服上述问题。
请参图4所示，为本发明实施例一射频功率放大器的电路图。本发明实施例一提供的一种射频功率放大器100，其包括输入端RF in、输出端RF out，第一晶体管Q 0及偏置电路10。
所述第一晶体管Q 0的基极连接至所述输入端RF in，所述第一晶体管Q 0的发射极接地，所述第一晶体管Q 0的集电极连接至所述输出端RF out，所述偏置电路10搭接至所述第一晶体管Q 0的基极与所述输入 端RF in之间。
具体的，本实施方式中，所述偏置电路10包括：第二晶体管Q 1、第三晶体管Q 2、第四晶体管Q 3、第一电容C L1、第二电容C L2、热效应抑制电阻R bias。其中，第一电容C L1和第二电容C L2均为滤波电容。
所述第三晶体管Q 2的基极连接至所述第三晶体管Q 2的集电极，所述第三晶体管Q 2的集电极连接至基准电压源V reg，所述第三晶体管Q 2的发射极连接至所述第二晶体管Q 1的集电极。
所述第二晶体管Q 1的基极连接至所述第二晶体管Q 1的集电极，所述第二晶体管Q 1的发射极接地。
所述第四晶体管Q 3的基极连接至所述第三晶体管Q 2的基极，所述第四晶体管Q 3的集电极连接至供电电压源V bat，所述第四晶体管Q 3的发射极通过串联所述热效应抑制电阻R bias后连接至所述第一晶体管Q 0的基极。
所述第一电容C L1的第一端连接至所述第四晶体管Q 3的发射极，所述第一电容C L1的第二端连接接地。
所述第二电容C L2的第一端连接至所述第四晶体管Q 3的基极，所述第二电容C L2的第二端连接至所述第一晶体管Q 0的集电极。
本实施方式中，更优的，为了提高可靠性，所述偏置电路10还包括第一电阻R 1和第二电阻R 2，所述第三晶体管Q 2的集电极串联所述第二电阻R 2后连接至所述基准电压源V reg，所述第二晶体管Q 1的发射极串联所述第一电阻R 1后接地。
为更好的实现电路的阻抗匹配，所述射频功率放大器100还包括串联至所述输入端RF in与所述第一晶体管Q 0的基极之间的输入匹配网络。本实施方式中，具体的，所述输入匹配网络为电容C构成。
同理，所述射频功率放大器100还包括输出匹配网络，所述输出匹配网络连接至所述第一晶体管Q 0的集电极和所述输出端RF out之间。本实施方式中，具体的，所述输出匹配网络由电感L和第三电容C 3构成；所述电感L的一端连接至所述第一晶体管Q 0的集电极，所述电 感L的另一端连接至电路电压源V cc；所述第三电容C 3串联至所述第一晶体管Q 0的集电极与所述输出端RF out之间。
继续结合图4，第二晶体管Q 1和第三晶体管Q 2构成钳位电压，使得电流I 2为稳定电流，调节第一电阻R 1和第二电阻R 2大小可调节电流I 2的大小。第三晶体管Q 2和第四晶体管Q 3组成电流镜，由于第三晶体管Q 3的放大功能，第三晶体管Q 3的发射极电流被镜像放大，因电流I 2为稳定电流，故电流I 1＝βI 2，其中β为放大系数。当输入功率增大，射频功率放大器100处于大功率工作状态时，第一晶体管Q 0的直流电流增加，因晶体管自热效应和二极管整流特性，第一晶体管Q 0的基级电位V b0会下降，射频线路上信号泄露进偏置电路10。由于第一电容C L1和第二电容C L2的存在，一部分高频信号先经过第一电容C L1到地，另一部分高频信号依次经过第四晶体管Q 3的发射级、第四晶体管Q 3的基级、第二电容C L2至第一晶体管Q 0的集电极，该反馈结构可将泄露的信号补充到输出信号中，因此可将第一晶体管Q 0的高频输出功率提高，且保持射频功率放大器100的线性度得到有效提高。第四晶体管Q 3的基级和发射级由于整流作用，该基级、发射级之间电压V be3降低，因为四晶体管Q 3的基级电位保持不变，所以对第一晶体管Q 0的基极电压V b0降低进行有效补偿，使得第一晶体管Q 0在高输入、输出功率状态下，保持静态工作点不变，因此增益压缩得到有效抑制。同时，偏置电阻R bias可有效的抑制第一晶体管Q 0的自热效应，从而提效地提高了偏置电路10的稳定性，即可提供稳定的静态电流，因此可保持第一晶体管Q 0一直工作在稳定的静态工作点，以此确保功率放大器的增益、输出功率和输出功率线性度的稳定性。
本发明的上述结构的偏置电路10形成带有温度补偿的有源偏置电路。在工作频段内的输出功率基本保持一致，对本发明提出的技术问题具有较优的改善效果。
需要说明的是，在一定范围内增大偏置电阻R bias可有效提高射频功率放大器100的静态工作点的稳定性，但超出这个范围后，若继续 增大偏置电阻R bias则会增加射频功率放大器100大信号输入时的非线性。增加偏置电阻R bias的大小对于输出功率的线性度提升表现为先上升后下降，在设计偏置电路10时，选择偏置电阻R bias的大小需结合射频功率放大器100的工作需求，偏置电阻R bias的大小一般在自然效应和线性度之间选择折中。
请结合图6-7所示，图6为图2中现有技术的射频功率放大器的偏置电路得到的输出功率和功率附加效率仿真效果图；图7为本发明射频功率放大器的偏置电路得到的输出功率和功率附加效率仿真效果图。从图6中可以看出，现有技术的射频功率放大器的电路的1dB功率压缩点为36.5dBm。而图7中可以看出，本发明的射频功率放大器的电路的1dB功率压缩点为38dBm。对比仿真结果可知，使用了本发的偏置电路对于射频功率放大器的高频输出功率有显著提升。
本发明中，对现有技术的传统偏置电路进行改进，结构简单容易实现；本发明中的偏置电路对射频功率放大器中的晶体管的热效应有很好的改善，并且可以提供稳定的电流，同时，还可以补偿射频功率放大器的高频输出功率，达到低频、中频、高频输出功率大小一致的目的。
本发明还提供另一种实施方式，请结合图5所示，图5为本发明实施例二射频功率放大器的电路图。本实施方式与上述图4所示的实施方式基本相同，不同在于所述偏置电路100还包括第三电阻R 3，所述第三电阻R 3串联于所述第四晶体管Q 3的基极与所述第二电容C L2的第一端之间。
第三电阻R 3可调节反馈深度，调节第三电阻R 3和第一电容C L1的值可调增大电路的稳定性(稳定系数K值)，并且第四晶体管Q3的基级电位Vb3保持不变，因此使得射频功率放大器100的线性度得到进一步的有效提高。
除上述区别外，与图4所示的实施例相同，且解决了同样的技术问题并达到了相同的技术效果。
与相关技术相比，本发明的射频功率放大器对偏置电路进行设计，结构简单，支持5G网络的工作频段(即高频信号)，该5G工作频段中，偏置电路由于设计的第一电容和第二电容的存在，将工作频段内的频率较低的一部分高频信号先经过第一电容滤波至地，以滤除该工作频段内频率较低的高频信号，而另一部分工作频段内频率较高的高频信号则依次经过第四晶体管的发射极、第四晶体管的基极、第二电容至第一晶体管的集电极，形成反馈结构，该反馈结构可将泄露的工作频段内频率较高的高频信号补充至输出信号中，因此有效提高了射频功率放大器在工作频段内的高频输出功率；且第四晶体管的基极电位保持不变，因此射频功率放大器的线性度得到有效提高。偏置电阻可有效的抑制晶体管的自热效应，有效提高偏置电路的稳定性，即可提供稳定的静态电流，因此可保持晶体管一直工作在稳定的静态工作点，以此确保功率放大器的增益、输出功率和输出功率线性度的稳定性。
需要说明的是，以上参照附图所描述的各个实施例仅用以说明本发明而非限制本发明的范围，本领域的普通技术人员应当理解，在不脱离本发明的精神和范围的前提下对本发明进行的修改或者等同替换，均应涵盖在本发明的范围之内。此外，除上下文另有所指外，以单数形式出现的词包括复数形式，反之亦然。另外，除非特别说明，那么任何实施例的全部或一部分可结合任何其它实施例的全部或一部分来使用。

Claims (7)

  1. 一种射频功率放大器，包括输入端、输出端，第一晶体管及偏置电路；所述第一晶体管的基极连接至所述输入端，所述第一晶体管的发射极接地，所述第一晶体管的集电极连接至所述输出端，所述偏置电路搭接至所述第一晶体管的基极与所述输入端之间，其特征在于，所述偏置电路包括：
    第二晶体管、第三晶体管、第四晶体管、第一电容、第二电容、热效应抑制电阻；
    所述第三晶体管的基极连接至所述第三晶体管的集电极，所述第三晶体管的集电极连接至基准电压源，所述第三晶体管的发射极连接至所述第二晶体管的集电极；
    所述第二晶体管的基极连接至所述第二晶体管的集电极，所述第二晶体管的发射极接地；
    所述第四晶体管的基极连接至所述第三晶体管的基极，所述第四晶体管的集电极连接至供电电压源，所述第四晶体管的发射极通过串联所述热效应抑制电阻后连接至所述第一晶体管的基极；
    所述第一电容的第一端连接至所述第四晶体管的发射极，所述第一电容的第二端连接接地；
    所述第二电容的第一端连接至所述第四晶体管的基极，所述第二电容的第二端连接至所述第一晶体管的集电极。
  2. 根据权利要求1所述的射频功率放大器，其特征在于，所述偏置电路还包括第一电阻和第二电阻，所述第三晶体管的集电极串联所述第二电阻后连接至所述基准电压源，所述第二晶体管的发射极串联所述第一电阻后接地。
  3. 根据权利要求1所述的射频功率放大器，其特征在于，所述偏置电路还包括第三电阻，所述第三电阻串联于所述第四晶体管的基极与所述第二电容的第一端之间。
  4. 根据权利要求1所述的射频功率放大器，其特征在于，所述射频功率放大器还包括串联至所述输入端与所述第一晶体管的基极之间的输入匹配网络。
  5. 根据权利要求4所述的射频功率放大器，其特征在于，所述输入匹配网络为电容构成。
  6. 根据权利要求1所述的射频功率放大器，其特征在于，所述射频功率放大器还包括输出匹配网络，所述输出匹配网络连接至所述第一晶体管的集电极和所述输出端之间。
  7. 根据权利要求6所述的射频功率放大器，其特征在于，所述输出匹配网络由电感和第三电容构成；所述电感的一端连接至所述第一晶体管的集电极，所述电感的另一端连接至电路电压源；所述第三电容串联至所述第一晶体管的集电极与所述输出端之间。
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CN116131774A (zh) * 2022-12-30 2023-05-16 锐石创芯(深圳)科技股份有限公司 功率放大器和射频前端电路
CN116260400A (zh) * 2022-12-31 2023-06-13 广州慧智微电子股份有限公司 偏置电路、功率放大器及电子设备
CN117277977B (zh) * 2023-11-22 2024-03-12 深圳飞骧科技股份有限公司 射频功率放大器及射频芯片模组
CN117439549B (zh) * 2023-12-13 2024-03-15 深圳飞骧科技股份有限公司 增益可调的线性低噪声放大器

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101924522A (zh) * 2010-09-07 2010-12-22 沈阳中科微电子有限公司 带有自适应线性化偏置电路的射频功率放大器
CN106230391A (zh) * 2016-07-13 2016-12-14 锐迪科微电子（上海）有限公司 一种功率放大器的线性化电流偏置电路
US20180287562A1 (en) * 2016-11-25 2018-10-04 Murata Manufacturing Co., Ltd. Power amplifier circuit
CN110120788A (zh) * 2019-06-06 2019-08-13 广东工业大学 一种用于功率放大器的偏置电路及功率放大器
CN110311632A (zh) * 2019-06-13 2019-10-08 广东工业大学 一种具有高温漂抑制能力的自适应偏置电路
CN114094950A (zh) * 2021-09-26 2022-02-25 深圳飞骧科技股份有限公司 射频功率放大器

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101924522A (zh) * 2010-09-07 2010-12-22 沈阳中科微电子有限公司 带有自适应线性化偏置电路的射频功率放大器
CN106230391A (zh) * 2016-07-13 2016-12-14 锐迪科微电子（上海）有限公司 一种功率放大器的线性化电流偏置电路
US20180287562A1 (en) * 2016-11-25 2018-10-04 Murata Manufacturing Co., Ltd. Power amplifier circuit
CN110120788A (zh) * 2019-06-06 2019-08-13 广东工业大学 一种用于功率放大器的偏置电路及功率放大器
CN110311632A (zh) * 2019-06-13 2019-10-08 广东工业大学 一种具有高温漂抑制能力的自适应偏置电路
CN114094950A (zh) * 2021-09-26 2022-02-25 深圳飞骧科技股份有限公司 射频功率放大器

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117353673A (zh) * 2023-12-04 2024-01-05 上海安其威微电子科技有限公司 射频放大电路、控制方法、控制模块和电子设备
CN117353673B (zh) * 2023-12-04 2024-03-15 上海安其威微电子科技有限公司 射频放大电路、控制方法、控制模块和电子设备

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