Radio frequency front-end module having input power protection

Abstract

The present invention is applicable to the technical field of radio frequency front ends, and particularly to a radio frequency front-end module having input power protection, comprising a signal input end, a bias circuit, an amplifier, and a signal output end that are sequentially electrically connected, wherein the bias circuit comprises a coupling circuit, a rectifier circuit, a switching circuit, and a mirror current source circuit; the coupling circuit is used for isolating a direct-current signal inputted by the signal input end, and allowing a radio frequency signal to pass; the rectifier circuit is used for rectifying the radio frequency signal and outputting an envelope signal; the mirror current source circuit is controlled by the envelope signal and outputs a bias current to the amplifier. The bias circuit in a radio frequency power module of the present invention can measure power inputted to the amplifier, and on the basis of the measured average power of an input signal, actively reduce the bias current inputted to a power amplifier, thereby achieving the purpose of protecting the power amplifier.

Description

RF front-end module with input power protection Technical Field

[0001] This invention relates to the field of radio frequency front-end technology, and in particular to a radio frequency front-end module with input power protection. Background Technology

[0002] As shown in Figure 1, in the prior art, a typical TDD system RF front-end module, such as a WIFI RF front-end module, consists of the following parts:

[0003] Power amplifier components are used to amplify the radio frequency signals output by the radio frequency chip;

[0004] The receiving circuitry, used to receive the signal path, typically includes a low-noise amplifier (LNA);

[0005] Radio frequency switching assembly, used to switch between transmit and receive paths;

[0006] The logic control component is used to control the working state of other components.

[0007] In wireless communication systems, radio frequency (RF) power amplifiers primarily amplify small RF signals before outputting them to antennas or other carriers. If the input signal exceeds the power amplifier's capacity, it can easily overload and damage the amplifier, causing the entire system to fail.

[0008] Some technologies protect power amplifier transistors by limiting the peak power of the input signal, but this method is often not suitable for high peak-to-average power ratio (PAPR) radio frequency signals such as Wi-Fi and 5G NR. The PAPR of signals like Wi-Fi and 5G NR can reach around 10dB, at which point the input limiting circuit may prematurely reduce the peak signal, leading to signal quality degradation. Summary of the Invention

[0009] This invention provides an RF front-end module with input power protection, which aims to solve the problem that existing methods for limiting the peak value of amplifier input signals can lead to signal quality degradation.

[0010] To address the aforementioned issues, this invention provides an RF front-end module with input power protection, comprising a signal input terminal, a bias circuit, an amplifier, and a signal output terminal; the signal input terminal, the bias circuit, the amplifier, and the signal output terminal are sequentially electrically connected.

[0011] The signal input terminal is connected to the input terminal of the amplifier;

[0012] The bias circuit includes a coupling circuit, a rectifier circuit, a switching circuit, and a current mirror circuit. The first terminal of the coupling circuit is connected to the signal input terminal, and the second terminal of the coupling circuit is connected to the first terminal of the rectifier circuit. The coupling circuit isolates the DC signal input to the signal input terminal and allows the radio frequency signal to pass through. The second terminal of the rectifier circuit is connected to the first terminal of the switching circuit. The rectifier circuit rectifies the radio frequency signal and outputs an envelope signal. The first terminal of the current mirror circuit is connected to the second terminal of the switching circuit, and the second terminal of the current mirror circuit is connected to the input terminal of the amplifier. The current mirror circuit is controlled by the envelope signal and outputs a bias current to the amplifier.

[0013] Furthermore, the amplifier includes a first MOSFET, the gate of which serves as the input terminal of the amplifier, the source of which serves as the first output terminal of the amplifier, and the drain of which serves as the second output terminal of the amplifier. The RF front-end module also includes a first capacitor, a second capacitor, and a first inductor. The signal input terminal is connected to the gate of the first MOSFET through the first capacitor in series. The first end of the second capacitor is connected to the drain of the first MOSFET, and the second end of the second capacitor is connected to the signal output terminal. The source of the first MOSFET is grounded, the first end of the first inductor is connected to the drain of the first MOSFET, and the second end of the first inductor is connected to a first external power supply. The first external power supply outputs a bias current to the drain of the first MOSFET.

[0014] Furthermore, the rectifier circuit includes a third capacitor, a second MOSFET, a fourth capacitor, and a fifth capacitor; the first terminal of the third capacitor serves as the first terminal of the rectifier circuit and is connected to the second terminal of the coupling circuit; the second terminal of the third capacitor is connected to the source, drain, and gate of the second MOSFET; the drain of the second MOSFET is connected to the gate of the second MOSFET and is also grounded; the source of the third MOSFET is connected to the first terminal of the fourth capacitor and the first terminal of the fifth capacitor, and serves as the second terminal of the rectifier circuit and is connected to the first terminal of the switching circuit; the second terminal of the fourth capacitor is connected to the second terminal of the fifth capacitor and is also grounded.

[0015] Furthermore, the capacitance value of the fourth capacitor is greater than the capacitance value of the fifth capacitor.

[0016] Furthermore, the switching circuit includes a fourth MOSFET, a first resistor, and a second resistor; the first end of the first resistor serves as the first end of the switching circuit and is connected to the second end of the rectifier circuit, and the second end of the first resistor is connected to the gate of the fourth MOSFET; the source of the fourth MOSFET is grounded, the drain of the fourth MOSFET serves as the second end of the switching circuit and is connected to the first end of the mirror current source circuit, the gate of the fourth MOSFET is connected to the first end of the second resistor, and the second end of the second resistor is grounded.

[0017] Furthermore, the current mirror circuit includes a fifth MOSFET, a sixth MOSFET, a seventh MOSFET, a third resistor, and a fourth resistor; the drain of the fifth MOSFET serves as the first terminal of the current mirror circuit and is connected to the second terminal of the switching circuit; the gate of the fifth MOSFET is connected to both the drain of the fifth MOSFET and the gate of the seventh MOSFET; the source of the fifth MOSFET is connected to both the drain of the sixth MOSFET and the gate of the sixth MOSFET; the source of the sixth MOSFET is grounded; the source of the seventh MOSFET serves as the second terminal of the current mirror circuit and is connected to the input terminal of the amplifier; the first terminal of the third resistor is connected to the drain of the fifth MOSFET, and the second terminal of the third resistor is connected to a second external power supply; the first terminal of the fourth resistor is connected to the drain of the seventh MOSFET, and the second terminal of the fourth resistor is connected to the second external power supply.

[0018] Furthermore, the coupling circuit includes a fifth resistor, the first end of which serves as the first end of the coupling circuit and is connected to the signal input terminal, and the second end of which serves as the second end of the coupling circuit and is connected to the first end of the rectifier circuit.

[0019] Furthermore, the coupling circuit includes a fifth resistor, a sixth capacitor, and a coupler; the first end of the fifth resistor is grounded, the second end of the fifth resistor is connected to the first input end of the coupler, the first output end of the coupler is connected to the first end of the sixth capacitor, the second input end of the coupler serves as the first end of the coupling circuit and is connected to the signal input end, and the second output end of the coupler is connected to the input end of the amplifier;

[0020] The coupling circuit further includes an eighth MOS transistor, a sixth resistor, and a seventh resistor; the gate of the eighth MOS transistor is connected to the second terminal of the sixth capacitor and the first terminal of the sixth resistor, the drain of the eighth MOS transistor is connected to the first terminal of the seventh resistor, and serves as the second terminal of the coupling circuit while also being connected to the first terminal of the rectifier circuit; the second terminals of the sixth resistor and the seventh resistor are both connected to a second external power supply.

[0021] Furthermore, the coupling circuit includes a fifth resistor and a sixth capacitor, with the first end of the fifth resistor serving as the first end of the coupling circuit and connected to the signal input terminal, and the second end of the fifth resistor connected to the first end of the sixth capacitor;

[0022] The coupling circuit further includes an eighth MOS transistor, a sixth resistor, and a seventh resistor. The gate of the eighth MOS transistor is connected to the second terminal of the sixth capacitor and the first terminal of the sixth resistor, respectively. The drain of the eighth MOS transistor is connected to the first terminal of the seventh resistor and serves as the second terminal of the coupling circuit, which is also connected to the first terminal of the rectifier circuit. The second terminals of the sixth resistor and the seventh resistor are both connected to a second external power supply.

[0023] The beneficial effect achieved by this invention is that it proposes a radio frequency power module with a bias circuit for input power protection. The bias circuit in this radio frequency power module can detect the power of the input amplifier and actively reduce the bias current of the input power amplifier based on the detected average power of the input signal, thereby protecting the power amplifier. Attached Figure Description

[0024] Figure 1 is a schematic diagram of the existing radio frequency front-end module structure;

[0025] Figure 2 is a circuit diagram of the RF front-end module with input power protection provided in an embodiment of the present invention;

[0026] Figure 3 is a circuit diagram of another RF front-end module with input power protection provided in an embodiment of the present invention;

[0027] Figure 4 is a circuit diagram of another RF front-end module with input power protection provided in an embodiment of the present invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0029] Please refer to Figure 2, which is a circuit diagram of an RF front-end module with input power protection provided in an embodiment of the present invention. The RF front-end module 100 includes a signal input terminal 101, a bias circuit 102, an amplifier 103, and a signal output terminal 104. The signal input terminal 101, the bias circuit 102, the amplifier 103, and the signal output terminal 104 are electrically connected in sequence.

[0030] The signal input terminal is connected to the input terminal of the amplifier;

[0031] The bias circuit 102 includes a coupling circuit 1021, a rectifier circuit 1022, a switching circuit 1023, and a current mirror circuit 1024. The first end of the coupling circuit 1021 is connected to the signal input terminal, and the second end of the coupling circuit 1021 is connected to the first end of the rectifier circuit. The coupling circuit 1021 is used to pick up the radio frequency signal input from the signal input terminal. The second end of the rectifier circuit 1022 is connected to the first end of the switching circuit 1023. The rectifier circuit 1022 is used to rectify the radio frequency signal and output an envelope signal. The first end of the current mirror circuit 1024 is connected to the second end of the switching circuit 1023, and the second end of the current mirror circuit 1024 is connected to the input terminal of the amplifier 103. The current mirror circuit 1024 is controlled by the envelope signal and outputs a bias current to the amplifier 103.

[0032] Specifically, the amplifier 103 includes a first MOSFET Q1, the gate of the first MOSFET Q1 serves as the input terminal of the amplifier, the source of the first MOSFET Q1 serves as the first output terminal of the amplifier, and the drain of the first MOSFET Q1 serves as the second output terminal of the amplifier. The RF front-end module also includes a first capacitor C1, a second capacitor C2, and a first inductor L1. The signal input terminal 101 is connected to the gate of the first MOSFET Q1 through series connection of the first capacitor C1. The first end of the second capacitor C2 is connected to the drain of the first MOSFET Q1, and the second end of the second capacitor C2 is connected to the signal output terminal. The source of the first MOSFET Q1 is grounded, the first end of the first inductor L1 is connected to the drain of the first MOSFET Q1, and the second end of the first inductor L1 is connected to a first external power supply. The first external power supply outputs a bias current to the drain of the first MOSFET Q1.

[0033] The rectifier circuit 1022 includes a third capacitor C3, a second MOSFET Q2, a third MOSFET Q3, a fourth capacitor C4, and a fifth capacitor C5. The first terminal of the third capacitor C3 serves as the first terminal of the rectifier circuit 1022 and is connected to the second terminal of the coupling circuit 1021. The second terminal of the third capacitor C3 is connected to the source, drain, and gate of the second MOSFET Q2. The drain of the second MOSFET Q2 is connected to the gate of the second MOSFET Q2 and is also grounded. The source of the third MOSFET Q3 is connected to the first terminals of the fourth capacitor C4 and the fifth capacitor C5, and serves as the second terminal of the rectifier circuit 1022 and is connected to the first terminal of the switching circuit 1023. The second terminal of the fourth capacitor C4 is connected to the second terminal of the fifth capacitor C5 and is also grounded.

[0034] The third capacitor, C3, is used to isolate DC signals between circuits.

[0035] The gates and drains of the second MOSFET Q2 and the third MOSFET Q3 are connected together to form a diode rectifier circuit, which rectifies the input RF signal and outputs the RF envelope signal to the fourth capacitor C4 and the fifth capacitor C5.

[0036] The capacitance of the fourth capacitor C4 is greater than that of the fifth capacitor C5. The fifth capacitor C5 has a smaller capacitance and is used to filter out unwanted radio frequency signals, while the fourth capacitor C4 has a larger capacitance and is used to filter out envelope fluctuation signals, so that the final output signal can more accurately reflect the average power of the input signal. In one possible implementation, if the amplifier circuit is only used to amplify constant envelope radio frequency signals, the fourth capacitor C4 can be removed to simplify the circuit.

[0037] The switching circuit 1023 includes a fourth MOSFET Q4, a first resistor R1, and a second resistor R2. The first end of the first resistor R1 serves as the first end of the switching circuit 1023 and is connected to the second end of the rectifier circuit 1022. The second end of the first resistor R1 is connected to the gate of the fourth MOSFET Q4. The source of the fourth MOSFET Q4 is grounded, and the drain of the fourth MOSFET Q4 serves as the second end of the switching circuit 1023 and is connected to the first end of the current mirror circuit 1024. The gate of the fourth MOSFET Q4 is connected to the first end of the second resistor R2, and the second end of the second resistor R2 is grounded.

[0038] The rectified output passes through the first resistor R1 to the current mirror circuit 1024, which is used to control the current of the current mirror circuit 1024. The second resistor R2 is used to provide a pull-down path for the MOSFET in the current mirror circuit 1024.

[0039] The current mirror circuit 1024 includes a fifth MOSFET Q5, a sixth MOSFET Q6, a seventh MOSFET Q7, a third resistor R3, and a fourth resistor R4. The drain of the fifth MOSFET serves as the first terminal of the current mirror circuit 1024 and is connected to the second terminal of the switching circuit 1023. The gate of the fifth MOSFET Q5 is connected to both the drain of the fifth MOSFET Q5 and the gate of the seventh MOSFET Q7. The source of the fifth MOSFET Q5 is connected to both the drain of the sixth MOSFET Q6 and the gate of the sixth MOSFET Q6. The source of the sixth MOSFET Q6 is grounded. The source of the seventh MOSFET Q7 serves as the second terminal of the current mirror circuit 1024 and is connected to the input terminal of the amplifier 103. The first terminal of the third resistor R3 is connected to the drain of the fifth MOSFET Q5, and the second terminal of the third resistor R3 is connected to a second external power supply. The first terminal of the fourth resistor R4 is connected to the drain of the seventh MOSFET Q7, and the second terminal of the fourth resistor R4 is connected to the second external power supply.

[0040] Clearly, the fifth MOSFET Q5, the sixth MOSFET Q6, and the seventh MOSFET Q7 form a current mirror circuit, whose overall output is used to provide a bias current IBIAS to the drain of the first MOSFET Q1.

[0041] In this embodiment of the invention, three implementation methods of the coupling circuit 1021 are provided.

[0042] Specifically, the first implementation is shown in Figure 2. The coupling circuit 1021 includes a fifth resistor R5. The first end of the fifth resistor R5 is connected to the signal input terminal 101 as the first end of the coupling circuit 1021, and the second end of the fifth resistor R5 is connected to the first end of the rectifier circuit 1022 as the second end of the coupling circuit 1021.

[0043] The fifth resistor R5 is connected to the RF path of the first MOSFET Q1. By selecting an appropriate value for the fifth resistor R5, a small portion of the RF energy of the input signal flows through the fifth resistor R5, while most of the RF energy enters the gate of the first MOSFET Q1 through the first capacitor C1. At the same time, the connection of the fifth resistor R5 has a small impact on the impedance of the RF path.

[0044] The second implementation is shown in Figure 3. The coupling circuit 1021 includes a fifth resistor R5, a sixth capacitor C6, and a coupler Coup1. The first end of the fifth resistor R5 is grounded, the second end of the fifth resistor R5 is connected to the first input end of the coupler Coup1, the first output end of the coupler Coup1 is connected to the first end of the sixth capacitor C6, the second input end of the coupler Coup1 serves as the first end of the coupling circuit 1021 and is connected to the signal input end 101, and the second output end of the coupler Coup1 is connected to the input end of the amplifier 103. The sixth capacitor C6 is mainly used to isolate DC signals and allow radio frequency signals to pass through.

[0045] The coupling circuit 1021 further includes an eighth MOSFET Q8, a sixth resistor R6, and a seventh resistor R7. The gate of the eighth MOSFET Q8 is connected to the second terminal of the sixth capacitor C6 and the first terminal of the sixth resistor R6, respectively. The drain of the eighth MOSFET Q8 is connected to the first terminal of the seventh resistor R7, and serves as the second terminal of the coupling circuit 1021, simultaneously connecting to the first terminal of the rectifier circuit 1022. The second terminals of both the sixth resistor R6 and the seventh resistor R7 are connected to a second external power supply. The sixth resistor R6 and the seventh resistor R7 provide a suitable DC bias for the eighth MOSFET Q8, enabling it to operate in the amplification range.

[0046] The third implementation is shown in Figure 4. The coupling circuit 1021 includes a fifth resistor R5 and a sixth capacitor C6. The first end of the fifth resistor R5 is connected to the signal input terminal 101 as the first end of the coupling circuit 1021, and the second end of the fifth resistor R5 is connected to the first end of the sixth capacitor C6.

[0047] The coupling circuit 1021 further includes an eighth MOSFET Q8, a sixth resistor R6, and a seventh resistor R7. The gate of the eighth MOSFET Q8 is connected to the second terminal of the sixth capacitor C6 and the first terminal of the sixth resistor R6, respectively. The drain of the eighth MOSFET Q8 is connected to the first terminal of the seventh resistor R7 and serves as the second terminal of the coupling circuit 1021, which is also connected to the first terminal of the rectifier circuit 1022. The second terminals of the sixth resistor R6 and the seventh resistor R7 are both connected to a second external power supply.

[0048] With the above circuit structure, when the input RF signal power is low, the signal power is also low after passing through the eighth MOSFET Q8 to the rectifier circuit. The DC voltage output by the rectifier circuit is low, which makes the fourth MOSFET Q4 cut off. The bias current IBIAS output by the current mirror is large, and the first MOSFET Q1 in the amplifier circuit works normally.

[0049] When the input RF signal power is large, the signal power is also large as it passes through the eighth MOSFET Q8 to the rectifier circuit. The DC voltage output by the rectifier circuit is high, which turns on the fourth MOSFET Q4. The current flowing through the third MOSFET Q3 increases, the voltage drop of the first resistor R1 increases, the bias current IBIAS output by the current mirror decreases, and the gain of the first MOSFET Q1 decreases, thereby protecting the first MOSFET Q1.

[0050] The circuit structure shown in Figure 2 is essentially a simplified circuit structure without the eighth MOS transistor Q8 shown in Figures 3 and 4. It is mainly designed for cases where the preset input signal power threshold is large. In this circuit structure, some bipolar transistors can be used to replace the circuit to perform the same electrical function. It is understood that the rectifier circuits in all embodiments of this invention achieve the same technical effect.

[0051] The beneficial effect achieved by this invention is that it proposes a radio frequency power module with a bias circuit for input power protection. The bias circuit in this radio frequency power module can detect the power of the input amplifier and actively reduce the bias current of the input power amplifier based on the detected average power of the input signal, thereby protecting the power amplifier.

[0052] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0053] The embodiments of the present invention have been described above with reference to the accompanying drawings. The disclosed embodiments are merely preferred embodiments of the present invention. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many equivalent changes in form without departing from the spirit and scope of the claims of the present invention, and all such changes are within the protection scope of the present invention.

Claims

1. A radio frequency front-end module with input power protection, comprising: a signal input terminal, a bias circuit, an amplifier, and a signal output terminal; wherein the signal input terminal, the bias circuit, the amplifier, and the signal output terminal are electrically connected in sequence; characterized in that, The signal input terminal is connected to the input terminal of the amplifier; The bias circuit includes a coupling circuit, a rectifier circuit, a switching circuit, and a current mirror circuit. The first terminal of the coupling circuit is connected to the signal input terminal, and the second terminal of the coupling circuit is connected to the first terminal of the rectifier circuit. The coupling circuit isolates the DC signal input to the signal input terminal and allows the radio frequency signal to pass through. The second terminal of the rectifier circuit is connected to the first terminal of the switching circuit. The rectifier circuit rectifies the radio frequency signal and outputs an envelope signal. The first terminal of the current mirror circuit is connected to the second terminal of the switching circuit, and the second terminal of the current mirror circuit is connected to the input terminal of the amplifier. The current mirror circuit is controlled by the envelope signal and outputs a bias current to the amplifier.

2. The RF front-end module with input power protection as described in claim 1, characterized in that, The amplifier includes a first MOS transistor, the gate of the first MOS transistor serves as the input terminal of the amplifier, the source of the MOS transistor serves as the first output terminal of the amplifier, and the drain of the MOS transistor serves as the second output terminal of the amplifier. The RF front-end module further includes a first capacitor, a second capacitor, and a first inductor; the signal input terminal is connected to the gate of the first MOSFET through the first capacitor in series, the first end of the second capacitor is connected to the drain of the first MOSFET, and the second end of the second capacitor is connected to the signal output terminal; the source of the first MOSFET is grounded, the first end of the first inductor is connected to the drain of the first MOSFET, the second end of the first inductor is connected to a first external power supply, and the first external power supply outputs a bias current to the drain of the first MOSFET.

3. The RF front-end module with input power protection as described in claim 1, characterized in that, The rectifier circuit includes a third capacitor, a second MOSFET, a fourth capacitor, and a fifth capacitor. The first terminal of the third capacitor serves as the first terminal of the rectifier circuit and is connected to the second terminal of the coupling circuit. The second terminal of the third capacitor is connected to the source, drain, and gate of the second MOSFET. The drain of the second MOSFET is connected to its gate and is also grounded. The source of the third MOSFET is connected to the first terminals of the fourth and fifth capacitors, and serves as the second terminal of the rectifier circuit, connected to the first terminal of the switching circuit. The second terminal of the fourth capacitor is connected to the second terminal of the fifth capacitor and is also grounded.

4. The RF front-end module with input power protection as described in claim 3, characterized in that, The capacitance value of the fourth capacitor is greater than the capacitance value of the fifth capacitor.

5. The RF front-end module with input power protection as described in claim 1, characterized in that, The switching circuit includes a fourth MOSFET, a first resistor, and a second resistor; the first end of the first resistor serves as the first end of the switching circuit and is connected to the second end of the rectifier circuit, and the second end of the first resistor is connected to the gate of the fourth MOSFET. The source of the fourth MOS transistor is grounded, the drain of the fourth MOS transistor is connected to the first terminal of the current mirror circuit as the second terminal of the switching circuit, the gate of the fourth MOS transistor is connected to the first terminal of the second resistor, and the second terminal of the second resistor is grounded.

6. The RF front-end module with input power protection as described in claim 1, characterized in that, The current mirror circuit includes a fifth MOSFET, a sixth MOSFET, a seventh MOSFET, a third resistor, and a fourth resistor. The drain of the fifth MOSFET serves as the first terminal of the current mirror circuit and is connected to the second terminal of the switching circuit. The gate of the fifth MOSFET is connected to both the drain of the fifth MOSFET and the gate of the seventh MOSFET. The source of the fifth MOSFET is connected to both the drain of the sixth MOSFET and the gate of the sixth MOSFET. The source of the sixth MOSFET is grounded. The source of the seventh MOSFET serves as the second terminal of the current mirror circuit and is connected to the input terminal of the amplifier. The first terminal of the third resistor is connected to the drain of the fifth MOSFET, and the second terminal of the third resistor is connected to a second external power supply. The first terminal of the fourth resistor is connected to the drain of the seventh MOSFET, and the second terminal of the fourth resistor is connected to the second external power supply.

7. The RF front-end module with input power protection as described in claim 1, characterized in that, The coupling circuit includes a fifth resistor, the first end of which serves as the first end of the coupling circuit and is connected to the signal input terminal, and the second end of which serves as the second end of the coupling circuit and is connected to the first end of the rectifier circuit.

8. The RF front-end module with input power protection as described in claim 1, characterized in that, The coupling circuit includes a fifth resistor, a sixth capacitor, and a coupler; the first end of the fifth resistor is grounded, the second end of the fifth resistor is connected to the first input end of the coupler, the first output end of the coupler is connected to the first end of the sixth capacitor, the second input end of the coupler serves as the first end of the coupling circuit and is connected to the signal input end, and the second output end of the coupler is connected to the input end of the amplifier. The coupling circuit further includes an eighth MOS transistor, a sixth resistor, and a seventh resistor; the gate of the eighth MOS transistor is connected to the second terminal of the sixth capacitor and the first terminal of the sixth resistor, the drain of the eighth MOS transistor is connected to the first terminal of the seventh resistor, and serves as the second terminal of the coupling circuit connected to the first terminal of the rectifier circuit; the second terminals of the sixth resistor and the seventh resistor are both connected to a second external power supply.

9. The RF front-end module with input power protection as described in claim 1, characterized in that, The coupling circuit includes a fifth resistor and a sixth capacitor. The first end of the fifth resistor is connected to the signal input terminal as the first terminal of the coupling circuit, and the second end of the fifth resistor is connected to the first terminal of the sixth capacitor. The coupling circuit further includes an eighth MOS transistor, a sixth resistor, and a seventh resistor. The gate of the eighth MOS transistor is connected to the second terminal of the sixth capacitor and the first terminal of the sixth resistor, respectively. The drain of the eighth MOS transistor is connected to the first terminal of the seventh resistor and serves as the second terminal of the coupling circuit, which is connected to the first terminal of the rectifier circuit. The second terminals of the sixth resistor and the seventh resistor are both connected to a second external power supply.

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