Negative feedback power amplifier circuit, power amplifier circuit control method, and negative feedback power amplifier system
By detecting the output power and performing negative feedback regulation in the negative feedback power amplifier circuit, the problems of low power value and high cost in the prior art are solved, and higher applicability and lower third-order intermodulation spurious emissions are achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHENZHEN SUNWAY COMM
- Filing Date
- 2023-03-09
- Publication Date
- 2026-06-02
Smart Images
Figure CN116155215B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of linear feedback technology for amplifiers, specifically to a negative feedback power amplifier circuit, a power amplifier circuit control method, and a negative feedback power amplifier system. Background Technology
[0002] With the development of wireless communication technology, linear power amplifiers are increasingly widely used. If the amplifier system processes multi-channel signals, the amplifier must be linear to avoid cross-adjustment. Negative feedback is a common linearization approach for power amplifiers. Most common negative feedback power amplifier designs use a combination of two mixers and a phase-locked loop (PLL). The feedback signal corresponding to the power amplifier's output power is subtracted from the second mixer's signal. This filtered signal is then fed back to the operational amplifier (OPA). The OPA adjusts the input power to reduce it, thus returning the power amplifier to its linear operating region. While this method effectively controls the linearization of the power amplifier, it is costly, uses multiple active RF devices, and suffers from difficulties in suppressing third-order intermodulation spurious signals generated by the two mixers. Furthermore, the OPA has a limited adjustable range, meaning the input power it can revert to is small, resulting in limited applicability. Summary of the Invention
[0003] The main technical problem addressed by the embodiments of this application is that existing negative feedback amplification designs have low power reversibility and high cost.
[0004] To solve the above-mentioned technical problems, one technical solution adopted in the embodiments of this application is: to provide a negative feedback power amplifier circuit, including: a power input module, a power amplifier module, an output port and a feedback module;
[0005] The power amplifier module is connected to the power input module and the output port respectively. The power input module is used to provide input power to the power amplifier module. The power amplifier module is used to receive and amplify the input power, and provide output power to the output port accordingly based on the input power.
[0006] The input terminal of the feedback module is connected to the output port, and the output terminal of the feedback module is connected to the control terminal of the power input module and the control terminal of the power amplifier module respectively. The feedback module is used to detect the output power, and when the output power is greater than a first preset threshold, it controls the power amplifier module to reduce the output power, or controls the power input module to reduce the input power.
[0007] Optionally, the feedback module includes a detection unit and an adjustment unit;
[0008] The input terminal of the detection unit is connected to the output port, the output terminal of the detection unit is connected to the input terminal of the adjustment unit, and the output terminal of the adjustment unit is connected to the control terminal of the power input module and the control terminal of the power amplifier module, respectively.
[0009] The detection unit is used to detect the output power, and outputs a first abnormal signal to the adjustment unit when the output power is greater than a first preset threshold and less than a second preset threshold, and outputs a second abnormal signal to the adjustment unit when the output power is greater than the second preset threshold.
[0010] The adjustment unit is used to receive the first abnormal signal and control the power amplifier module to reduce the output power based on the first abnormal signal, and is also used to receive the second abnormal signal and control the power input module to reduce the input power based on the second abnormal signal.
[0011] Optionally, the adjustment unit includes a microcontroller, which is configured as follows:
[0012] Upon receiving the first abnormal signal, an adjustment signal is provided to the power amplifier module so that the power amplifier module reduces the output power according to the adjustment signal;
[0013] Upon receiving the second abnormal signal, an attenuation signal is provided to the power input module to reduce the input power.
[0014] Optionally, the power amplifier module includes an RF transistor, and the adjustment unit further includes a digital power supply. The digital power supply is connected to the microcontroller and also connected to the control terminal of the RF transistor. The RF transistor is used to receive and amplify the input power, and the digital power supply is used to receive the adjustment signal and control the signal amplification range of the RF transistor based on the adjustment signal to reduce the output power.
[0015] Optionally, the power input module includes an adjustable attenuator connected to the microcontroller. The adjustable attenuator is used to receive the attenuation signal and reduce the input power based on the attenuation signal.
[0016] To solve the above-mentioned technical problems, another technical solution adopted in this application is: providing a power amplifier circuit control method applied to a negative feedback power amplifier circuit, wherein the negative feedback power amplifier circuit includes a power input module, a power amplifier module, an output port, and a feedback module, the power amplifier module is connected to the power input module and the output port respectively, the input terminal of the feedback module is connected to the output port, and the output terminal of the feedback module is connected to the control terminal of the power input module and the control terminal of the power amplifier module respectively, the method comprising:
[0017] The output power of the output port is detected by the feedback module;
[0018] If the output power is greater than the first preset threshold, control the power input module to reduce the input power, or control the power amplifier module to reduce the output power.
[0019] Optionally, the feedback module includes a detection unit and an adjustment unit. The input terminal of the detection unit is connected to the output port, and the output terminal of the detection unit is connected to the input terminal of the adjustment unit. The output terminal of the adjustment unit is connected to the control terminal of the power input module and the control terminal of the power amplifier module, respectively. Detecting the output power of the output port through the feedback module includes:
[0020] The output power is detected by the detection unit;
[0021] If the output power is greater than a first preset threshold and less than a second preset threshold, then the detection unit outputs a first abnormal signal to the adjustment unit.
[0022] If the output power is greater than the second preset threshold, the detection unit outputs a second abnormal signal to the adjustment unit.
[0023] Optionally, controlling the power amplifier module to reduce the output power includes:
[0024] The first abnormal signal is received by the adjustment unit;
[0025] Based on the first abnormal signal, the power amplifier module is controlled to reduce the output power.
[0026] Optionally, controlling the power input module to reduce the input power includes:
[0027] The second abnormal signal is received through the adjustment unit;
[0028] Based on the second abnormal signal, the power input module is controlled to reduce the input power.
[0029] To solve the above-mentioned technical problems, another technical solution adopted in the embodiments of this application is to provide a negative feedback power amplifier system, including the negative feedback power amplifier circuit described above.
[0030] Unlike related technologies, this application provides a negative feedback power amplifier circuit, a power amplifier circuit control method, and a negative feedback power amplifier system. The circuit includes a power input module, a power amplifier module, an output port, and a feedback module. The power amplifier module is connected to both the power input module and the output port. The input terminal of the feedback module is connected to the output port, and the output terminal of the feedback module is connected to both the control terminal of the power input module and the control terminal of the power amplifier module. This circuit can detect whether the power amplifier module is operating in the linear operating region. When it exceeds the linear operating region, the feedback module performs negative feedback adjustment of the power amplifier module, controlling the power amplifier module to reduce its output power, or controlling the power input module to reduce its input power, causing the power amplifier module to return to the linear operating region. The negative feedback power amplifier circuit, power amplifier circuit control method, and negative feedback power amplifier system provided in this application do not require multiple mixers or other RF active devices, thus controlling costs, reducing third-order intermodulation and spurious emissions, and by including a power input module, improving the adjustment range of the input power, making it more applicable. Attached Figure Description
[0031] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.
[0032] Figure 1 This is a schematic diagram of a power amplifier in an application scenario provided in the embodiments of this application;
[0033] Figure 2 This is a schematic diagram of the input-output curves of the power amplifier provided in the embodiments of this application;
[0034] Figure 3 This is a structural block diagram of a negative feedback power amplifier circuit provided in an embodiment of this application;
[0035] Figure 4 This is a circuit diagram of a negative feedback power amplifier circuit provided in an embodiment of this application;
[0036] Figure 5 This is another schematic diagram of the input-output curves of the power amplifier provided in the embodiments of this application. Detailed Implementation
[0037] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. It should be noted that, unless otherwise specified, the various features in the embodiments of this application can be combined with each other, all within the scope of protection of this application. When an element is described as "connected" to another element, it can be directly connected to the other element, or there may be one or more intervening elements. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than that shown in the flowchart.
[0038] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items, and the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0039] Please see Figure 1 , Figure 1 This is a schematic diagram of a common power amplifier, also referred to as a power amplifier module in this embodiment. A typical power amplifier module primarily amplifies the input power pin using an RF transistor Q1 and its surrounding circuitry. Figure 1 As shown, capacitors C1 and C2 are both DC blocking capacitors. The two coils connected to the input matching network and the output matching network are both ferrite core chokes, which can suppress and isolate the coupling between high-frequency signals and DC power supply. They are powered by bias voltage V1 and power supply voltage VCC respectively.
[0040] Ideally, the input-output curves of the power amplifier module should satisfy a linear function. Please refer to... Figure 2 , Figure 2 In the coordinate system, the horizontal axis represents input power, and the vertical axis represents output power. The dashed line represents the ideal linear ratio curve of input and output power, while the solid line represents the actual output curve. As shown in the figure, due to the nonlinear effect of the RF transistor, when the input power exceeds a certain threshold, the output power does not satisfy a linear function with the input power; that is, the transistor is operating in the nonlinear region. In most cases, users need the power amplifier module to operate in the linear region. For example, when using a power amplifier system to process multi-channel signals, the generator needs to operate in the linear region to avoid cross-adjustment of the signal.
[0041] This application provides a negative feedback power amplifier circuit. Please refer to [link / reference]. Figure 3 The circuit includes a power input module 11, a power amplifier module 12, a feedback module 13, and an output port. Figure 3 In this diagram, Pout represents the output power of the output port, and Pin represents the input power of the power input module 11. The power amplifier module 12 is connected to both the power input module 11 and the output port. The input terminal of the feedback module 13 is connected to the output port, and the output terminal of the feedback module 13 is connected to both the control terminal of the power input module 11 and the control terminal of the power amplifier module 12.
[0042] The power input module 11 can provide input power to the power amplifier module 12. The power amplifier module 12 can receive and amplify the input power, and provide corresponding output power to the output port based on the input power. The feedback module 13 can detect the magnitude of the output power. When the output power is greater than a first preset threshold, the feedback module 13 can control the power amplifier module 12 to reduce the output power, or control the power input module 11 to reduce the input power. For example, please refer to... Figure 2 In some embodiments, the first preset threshold can be the value corresponding to y1. When the output power is detected to be greater than y1, it is considered that the power amplifier module (mainly the RF transistor) is working in the nonlinear region and needs to be adjusted by feedback so that the power amplifier module returns to the linear operating region.
[0043] It should be noted that the above-mentioned value setting for the first preset threshold is only an example, and this application does not limit this value. In other embodiments, other suitable values can be set according to actual usage.
[0044] Specifically, the feedback module 13 includes a detection unit 131 and an adjustment unit 132. The input terminal of the detection unit 131 is connected to the output port, the output terminal of the detection unit 131 is connected to the input terminal of the adjustment unit 132, and the output terminal of the adjustment unit 132 is connected to the control terminal of the power input module 11 and the control terminal of the power amplifier module 12, respectively.
[0045] The detection unit 131 can detect the output power Pout. When the output power is greater than the first preset threshold and less than the second preset threshold, the detection unit 131 outputs a first abnormal signal to the adjustment unit 132. When the output power is greater than the second preset threshold, the detection unit 131 outputs a second abnormal signal to the adjustment unit 132. The adjustment unit 132 can receive the first abnormal signal and control the power amplifier module 12 to reduce the output power based on the first abnormal signal. It can also receive the second abnormal signal and control the power input module 11 to reduce the input power based on the second abnormal signal.
[0046] In the negative feedback power amplifier circuit provided in this application, combined with Figure 1The schematic diagram of the power amplifier module shown in the figure shows that the control terminal of the RF transistor Q1 can be connected to the output terminal of the adjustment unit 132. Based on the characteristics of the transistor, changing the current at the control terminal of the RF transistor Q1 can correspondingly change the output voltage of the RF transistor Q1. The circuit provided in this embodiment can control the reduction of the current at the control terminal of the RF transistor Q1 when the output power is greater than a first preset threshold, so that the RF transistor Q1 returns to the linear operating region, reducing the output voltage of the RF transistor Q1 and indirectly reducing the output power. However, the range of return to linearity is limited in this way. Therefore, in some embodiments, the second preset threshold can be set according to the characteristics and parameters of the RF transistor.
[0047] For example, please combine Figure 2 Assume that when the input power is less than x2, the RF transistor Q1 can be brought back to the normal linear operating region by controlling the current at the control terminal of the RF transistor Q1. However, when the input power is greater than x2, the RF transistor Q1 cannot be brought back to the normal linear operating region by adjusting the current at the control terminal of the RF transistor Q1. This indicates that the back-off value corresponding to x2 exceeds the back-off limit of the RF transistor Q1. In this case, the output power y2 corresponding to x2 can be set as the second preset threshold.
[0048] When the output power is detected to be greater than the second preset threshold, the adjustment unit 132 can control the power input module 11 to reduce the input power accordingly, so that the RF transistor Q1 in the power amplifier module 12 returns to the linear operating region.
[0049] It should be noted that the above-mentioned numerical setting of the second preset threshold is only an example setting, used to select the feedback adjustment method (adjusted through the power input module or adjusted through the power amplifier module). In actual use, it may differ from the above numerical setting. For example, in some embodiments, it may be set to a value greater than y2 and less than y1. This application does not limit this value. It is understood that in some embodiments, the circuit may also be set to only perform feedback adjustment through the power input module 11. That is, it is not necessary to set the second preset threshold or select the feedback adjustment method. Only the first preset threshold is set. If the output power is detected to exceed the first preset threshold, the power input module 11 is controlled to reduce the input power accordingly, thereby causing the power amplifier module 12 to return to the linear operating region.
[0050] Please combine Figure 4 In the negative feedback power amplifier circuit provided in this application embodiment, the detection unit 131 may include an RF detector 1311 and an unequal power divider 1312. Figure 4 The diagram shows the main structure of an RF detector 1311. The adjustment unit 132 may include a microcontroller and a digital power supply, and the power input module 11 may be an adjustable attenuator.
[0051] Specifically, the unequal power divider can feed back the output power's corresponding yout / n to the RF detector. The RF detector can then detect the output power based on this. In conjunction with the microcontroller, when the output power is greater than a first preset threshold but less than a second preset threshold, a first abnormal signal is output to the microcontroller. When the output power is greater than the second preset threshold, a second abnormal signal is output to the microcontroller. The microcontroller can determine the input power based on the received first or second abnormal signal and select a feedback adjustment method. For example, upon receiving the first abnormal signal, an adjustment signal is provided to the RF transistor Q1 to reduce the control terminal current of the RF transistor Q1, causing the RF transistor Q1 to return to the linear operating region. Upon receiving the second abnormal signal, an attenuation signal is provided to the adjustable attenuator to reduce the input power.
[0052] It should be noted that the descriptions of the first and second abnormal signals are merely for the convenience of explaining the two different adjustment methods later. In reality, the RF detector outputs a voltage signal corresponding to the power feedback from the unequal power divider. This voltage signal is related to the output power. The microcontroller can determine the current input power based on this voltage signal and then adjust the power accordingly. The aforementioned first and second abnormal signals can be approximated as voltage signals with different values. The microcontroller determines the current input power based on the different voltage signal values and then selects which adjustment method to use for the corresponding input power.
[0053] The adjustment unit 132 may include a digital power supply, which is connected to the control terminal of the microcontroller and the radio frequency transistor. When the microcontroller receives the first abnormal signal, it can change the current at the control terminal of the radio frequency transistor Q1 by controlling the digital power supply, so that the radio frequency transistor Q1 returns to the linear operating region.
[0054] The negative feedback power amplifier circuit provided in this application includes a power input module, a power amplifier module, an output port, and a feedback module. The power amplifier module is connected to both the power input module and the output port. The input terminal of the feedback module is connected to the output port, and the output terminal of the feedback module is connected to both the control terminal of the power input module and the control terminal of the power amplifier module. This circuit can detect whether the power amplifier module is operating in the linear operating region. When it exceeds the linear operating region, the feedback module performs negative feedback adjustment of the power amplifier module, controlling the power amplifier module to reduce its output power, or controlling the power input module to reduce its input power, causing the power amplifier module to fall back to the linear operating region. The negative feedback power amplifier circuit provided in this application does not require multiple mixers or other RF active devices, thus controlling costs, reducing third-order intermodulation and spurious emissions, and improving the adjustment range of input power by including a power input module, making it more versatile.
[0055] This application provides a power amplifier circuit control method applied to a negative feedback power amplifier circuit. The circuit structure and other technical details of this negative feedback power amplifier circuit can be found in the above embodiments and will not be repeated here. The method includes:
[0056] S11. The output power of the output port is detected through the feedback module.
[0057] Please combine Figure 4 Specifically, the feedback module includes a detection unit and an adjustment unit, and the detection of the output power at the output port through the feedback module includes:
[0058] S111, The output power is detected by the detection unit.
[0059] S112. If the output power is greater than the first preset threshold and less than the second preset threshold, the first abnormal signal is output to the adjustment unit through the detection unit.
[0060] S113. If the output power is greater than the second preset threshold, the detection unit outputs a second abnormal signal to the adjustment unit.
[0061] The detection unit can be an RF detector, and the adjustment unit can be a microcontroller. Combined with the microcontroller, when the output power is greater than a first preset threshold and less than a second preset threshold, the detection unit outputs a first abnormal signal to the microcontroller; when the output power is greater than the second preset threshold, the detection unit outputs a second abnormal signal to the microcontroller.
[0062] S12. If the output power is greater than the first preset threshold, control the power input module to reduce the input power, or control the power amplifier module to reduce the output power. Wherein, if the output power is greater than the first preset threshold and less than the second preset threshold, the following steps S121-122 can be executed; if the output power is greater than the second preset threshold, the following steps S123-S124 can be executed.
[0063] S121, Receive the first abnormal signal through the adjustment unit.
[0064] S122. The power amplifier module is controlled to reduce output power based on the first abnormal signal. When the microcontroller receives the first abnormal signal, it indicates that although the output power exceeds the range corresponding to the linear operating region, it is still within the adjustable range of the RF transistor Q1. Figure 4 The control 1 shown can reduce the current at the control terminal of the RF transistor Q1 by controlling the digital power supply, thereby reducing the output voltage of the RF transistor Q1 and indirectly reducing the output power, so that the RF transistor Q1 returns to the linear operating region.
[0065] S123, Receive the second abnormal signal through the adjustment unit.
[0066] S124. Based on the second abnormal signal, the power input module is controlled to reduce the input power. When the microcontroller receives the second abnormal signal, it indicates that the input power needs to be reduced to control the RF transistor Q1 to return to the linear operating region. Figure 4 As shown in control 2, the microcontroller provides an attenuation signal to the adjustable attenuator, which controls the adjustable attenuator to reduce the input power, causing the RF transistor Q1 to fall back to the linear operating region.
[0067] In some embodiments, please combine Figure 5 When the input power is too high, the relationship between output power and input power may also exhibit the following characteristics: Figure 5 As shown, when the output power is y3, the unequal power divider feeds back the output power y3 / n to the RF detector, where n is the unequal division coefficient, usually an integer greater than 1, such as 2, 3, 4, 5, etc. The RF detector detects the power fed back from the unequal power divider and transmits the corresponding voltage signal to the microcontroller. The microcontroller reads the signal transmitted by the RF detector and determines the current input power as x3. If the input power is not adjusted immediately, and assuming the input power continues to increase to x4 in the next second, the microcontroller can indirectly detect the change in output power to y4 through the unequal power divider and the RF detector. Since y4 is less than y3, the microcontroller can detect that the relationship curve between input power and output power is in the negatively correlated part of the curve. The microcontroller will control the adjustable attenuator to reduce the input power, causing the input power to decrease by (x4-x) dBm, so as to control the power amplifier module to return to the linear region (assuming x is the threshold of the linear operating region). It is understandable that the above example is only a control example under the condition of excessive input power, and the above judgment mode is not used for input power adjustment in all cases.
[0068] The power amplifier circuit control method provided in this application is applied to a negative feedback power amplifier circuit. By detecting the output power, the method adjusts the negative feedback power amplifier circuit based on the output power level to ensure the RF transistor operates in the linear operating region. Specifically, when the output power is greater than a first preset threshold but less than a second preset threshold, the power amplifier module is controlled to reduce the output power to keep the RF transistor operating in the linear operating region. When the output power is greater than the second preset threshold, the power input module is controlled to reduce the input power to keep the RF transistor operating in the linear operating region. This method can detect whether the power amplifier module is operating in the linear operating region, and when it exceeds the linear operating region, it uses a feedback module to perform negative feedback adjustment of the power amplifier module, causing the power amplifier module to return to the linear operating region. Furthermore, by setting a power input module, the adjustment range of the input power is improved, resulting in greater applicability.
[0069] This application provides a negative feedback power amplifier system, including the negative feedback power amplifier circuit described in the above embodiments. It should be noted that the negative feedback power amplifier system can execute the power amplifier circuit control method provided in this application, possessing the corresponding functional modules and beneficial effects of the method. Technical details not described in detail in the negative feedback power amplifier system embodiments can be found in the power amplifier circuit control method provided in this application.
[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them; under the concept of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of this application as described above, which are not provided in detail for the sake of brevity; although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.
Claims
1. A negative feedback power amplifier circuit, characterized in that, include: The system includes a power input module, a power amplifier module, an output port, and a feedback module. The feedback module comprises a detection unit and an adjustment unit. The power amplifier module is connected to both the power input module and the output port. The input terminal of the detection unit is connected to the output port, and the output terminal of the detection unit is connected to the input terminal of the adjustment unit. The output terminal of the adjustment unit is connected to both the control terminal of the power input module and the control terminal of the power amplifier module. The power amplifier module includes an RF transistor. The power input module is used to provide input power to the power amplifier module, and the power amplifier module is used to receive and amplify the input power, and provide output power to the output port accordingly based on the input power; The feedback module is used to detect the output power, and when the output power is greater than a first preset threshold, control the power amplifier module to reduce the output power, or control the power input module to reduce the input power; Wherein: the detection unit is used to detect the output power, and outputs a first abnormal signal to the adjustment unit when the output power is greater than a first preset threshold and less than a second preset threshold, and outputs a second abnormal signal to the adjustment unit when the output power is greater than the second preset threshold; The adjustment unit is used to receive the first abnormal signal and control the power amplifier module to reduce the output power based on the first abnormal signal; it is also used to receive the second abnormal signal and control the power input module to reduce the input power based on the second abnormal signal. The first preset threshold is the output power threshold corresponding to when the RF transistor enters the nonlinear operating region; the second preset threshold is the output power threshold corresponding to when the RF transistor cannot return to the linear operating region by adjusting the bias. The power input module includes an adjustable attenuator connected to the adjustment unit, the adjustable attenuator being used to reduce the input power in response to the control of the adjustment unit to reduce the input power.
2. The negative feedback power amplifier circuit according to claim 1, characterized in that, The adjustment unit includes a microcontroller, which is configured as follows: Upon receiving the first abnormal signal, an adjustment signal is provided to the power amplifier module so that the power amplifier module reduces the output power according to the adjustment signal; Upon receiving the second abnormal signal, an attenuation signal is provided to the power input module to reduce the input power.
3. The negative feedback power amplifier circuit according to claim 2, characterized in that, The adjustment unit also includes a digital power supply, which is connected to the microcontroller and the control terminal of the radio frequency transistor. The radio frequency transistor is used to receive and amplify the input power, and the digital power supply is used to receive the adjustment signal and control the signal amplification range of the radio frequency transistor based on the adjustment signal to reduce the output power.
4. The negative feedback power amplifier circuit according to claim 2, characterized in that, The adjustable attenuator is connected to the microcontroller. The adjustable attenuator is used to receive the attenuation signal and reduce the input power based on the attenuation signal.
5. A power amplifier circuit control method, applied to a negative feedback power amplifier circuit, characterized in that, The negative feedback power amplifier circuit is the negative feedback power amplifier circuit as described in any one of claims 1-4, and the method includes: The output power of the output port is detected by the feedback module; If the output power is greater than the first preset threshold, control the power input module to reduce the input power, or control the power amplifier module to reduce the output power.
6. The method according to claim 5, characterized in that, The step of detecting the output power of the output port through the feedback module includes: The output power is detected by the detection unit; If the output power is greater than a first preset threshold and less than a second preset threshold, then the detection unit outputs a first abnormal signal to the adjustment unit. If the output power is greater than the second preset threshold, the detection unit outputs a second abnormal signal to the adjustment unit.
7. The method according to claim 6, characterized in that, The step of controlling the power amplifier module to reduce the output power includes: The first abnormal signal is received by the adjustment unit; Based on the first abnormal signal, the power amplifier module is controlled to reduce the output power.
8. The method according to claim 6, characterized in that, The control of the power input module to reduce the input power includes: The second abnormal signal is received through the adjustment unit; Based on the second abnormal signal, the power input module is controlled to reduce the input power.
9. A negative feedback power amplifier system, characterized in that, Includes the negative feedback power amplifier circuit as described in any one of claims 1-4.