Front-end circuit based on CLYC scintillator and SiPM detector and signal filtering and amplifying processing method

Abstract

The invention discloses a front-end circuit based on a CLYC scintillator and a SiPM detector. Comprising a first-stage detection circuit, a second-stage pole zero cancellation circuit, a third-stage in-phase proportion amplification circuit, a fourth-stage in-phase proportion amplification circuit and a fifth-stage Sallen-Key type low-pass filtering amplification circuit which are connected in sequence, wherein the first-stage detection circuit is composed of a CLYC scintillator and an SiPM detector which are connected with each other; a signal forms a multiplied electric signal through the first-stage detection circuit, the second-stage polar zero cancellation circuit recovers a rapid rising edge of a pulse signal, and the third-stage in-phase proportional amplification circuit and the fourth-stage in-phase proportional amplification circuit realize proportional amplification of the signal so as to ensure long-distance transmission of the signal. And the fifth-stage Sallen-Key type low-pass filtering and amplifying circuit is used for filtering the signal so as to reduce the influence of high-frequency noise and outputting a voltage signal. The circuit effectively processes the standard output waveform of the detector, and ensures that the waveform can be transmitted for a long distance.

Description

Technical Field

[0001] The invention belongs to the technical field of nuclear radiation detection, and in particular relates to a front-end circuit based on a CLYC scintillator and a SiPM detector and a signal filtering and amplifying processing method. Background Art

[0002] The processing of neutron waveform signals collected in neutron detection has always been a research problem. Ordinary neutron detector circuits have high average ionization energy, weak output signals, and small amounts of collected charge, which makes the output signals very susceptible to the influence of distributed capacitance. The high light energy yield of CLYC for neutrons and the multiplying effect of SiPM make neutron signal collection more accurate, but the measured voltage signal still has large high-frequency noise, making the output waveform signal difficult to distinguish and collect. Summary of the invention

[0003] In order to overcome the problems existing in the prior art, the present invention aims to provide a front-end circuit and a signal filtering and amplification processing method based on a CLYC scintillator and a SIPM detector. The present invention uses a combination of CLYC and SiPM to complete neutron collection. The two-stage amplification circuit is combined with a Sallen-Key type filtering circuit so that the circuit can achieve high gain under stable working conditions without introducing too much high-frequency noise.

[0004] To achieve the above object, the present invention is implemented through the following technical solutions:

[0005] A front-end circuit based on a CLYC scintillator and a SiPM detector comprises a first-stage detection circuit composed of a connected CLYC scintillator and a SiPM detector, a second-stage pole-zero cancellation circuit, a third-stage in-phase proportional amplifier circuit, a fourth-stage in-phase proportional amplifier circuit and a fifth-stage Sallen-Key type low-pass filter amplifier circuit which are connected in sequence; a signal passes through the first-stage detection circuit to form a multiplied electrical signal, the second-stage pole-zero cancellation circuit restores the fast rising edge of the pulse signal, the third-stage in-phase proportional amplifier circuit and the fourth-stage in-phase proportional amplifier circuit realize proportional amplification of the signal to ensure that the signal can be transmitted over a long distance, and the fifth-stage Sallen-Key type low-pass filter amplifier circuit filters the signal to reduce the influence of high-frequency noise, and outputs a voltage signal.

[0006] The CLYC scintillator in the first-stage detection circuit is made of CLYC crystal material with high neutron and gamma light energy yield. Nine MicroFJ-30035-TSVs are selected to design the SiPM detector in a 3×3 SiPM array format to adapt to the size of the CLYC scintillator, ensuring that the particle signals collected by the CLYC scintillator can be fully transmitted to the SiPM detector. The SiPM detector converts the optical signal into an electrical signal and amplifies it as the input signal of the front-end circuit.

[0007] The pole-zero cancellation circuit of the second stage includes a first resistor R1, a first capacitor C1 and a second resistor R2. The first capacitor C1 and the first resistor R1 are connected in parallel. One end of the first resistor R1 is connected to the signal input end and the first capacitor C1, and the other end is connected to the first capacitor C1 and the +IN end of the first operational amplifier IC1 of the third-stage in-phase proportional amplifier circuit. One end of the first capacitor C1 is connected to the first resistor R1 and the signal input end, and the other end is connected to the first resistor R1 and the +IN end of the first operational amplifier IC1 of the third-stage in-phase proportional amplifier circuit. One end of the second resistor R2 is connected to the +IN end of the first operational amplifier IC1 of the third-stage in-phase proportional amplifier circuit, the first resistor R1 and the first capacitor C1, and the other end is grounded.

[0008] The third-stage in-direction proportional amplifier circuit includes a third resistor R3, a fourth resistor R4 and a first operational amplifier IC1. One end of the third resistor R3 is grounded, and the other end is connected to the fourth resistor R4 and the -IN end of the first operational amplifier IC1. One end of the fourth resistor R4 is connected to the third resistor R3 and the -IN end of the first operational amplifier IC1, and the other end is connected to the fifth resistor R5 of the fourth-stage in-direction proportional amplifier circuit and the OUT end of the first operational amplifier IC1.

[0009] The fourth-stage in-phase proportional amplifier circuit includes a fifth resistor R5, a sixth resistor R6, a seventh resistor R7 and a second operational amplifier IC2. One end of the fifth resistor R5 is connected to the OUT end of the first operational amplifier IC1 of the third-stage in-phase proportional amplifier circuit and the fourth resistor R4, and the other end is connected to the +IN end of the second operational amplifier IC2; one end of the sixth resistor R6 is respectively connected to the -IN end of the second operational amplifier IC2 and the seventh resistor R7, and the other end is grounded; one end of the seventh resistor R7 is respectively connected to the -IN end of the second operational amplifier IC2 and the sixth resistor R6, and the other end is respectively connected to the OUT end of the second operational amplifier IC2 and the eighth resistor R8 of the fifth-stage Sallen-Key type low-pass filter amplifier circuit.

[0010] The fifth-stage Sallen-Key low-pass filter amplifier circuit includes an eighth resistor R8, a ninth resistor R9, a second capacitor C2, a third capacitor C3 and a third operational amplifier IC3; one end of the eighth resistor R8 is respectively connected to the second operational amplifier IC2OUT terminal and the seventh resistor R7 of the fourth-stage in-phase proportional amplifier circuit, and the other end is respectively connected to the second capacitor C2 and the ninth resistor R9; one end of the ninth resistor R9 is respectively connected to the eighth resistor R8 and the second capacitor C2, and the other end is respectively connected to the +IN terminal of the third operational amplifier IC3 and the third capacitor C3; one end of the second capacitor C2 is respectively connected to the eighth resistor R8 and the ninth resistor R9, and the other end is connected to the OUT terminal of the third operational amplifier IC3; one end of the third capacitor C3 is respectively connected to the ninth resistor R9 and the +IN terminal of the third operational amplifier IC3, and the other end is grounded; the -IN terminal of the third operational amplifier IC3 is connected to the OUT terminal; the third operational amplifier IC3OUT terminal outputs a signal.

[0011] The signal filtering and amplification processing method based on the front-end circuit of the CLYC scintillator and the SiPM detector comprises the following steps:

[0012] Step 1: Particles are injected into the detection circuit composed of CLYC scintillator and SiPM detection and converted into a multiplied voltage signal.

[0013] Step 2: The voltage signal is transmitted to the second-stage pole-zero cancellation circuit to process the rising edge and reduce the rise time of the waveform;

[0014] Step 3: The third-stage proportional amplifier circuit and the fourth-stage proportional amplifier circuit realize proportional amplification of the voltage signal. The third-stage proportional amplifier circuit and the fourth-stage proportional amplifier circuit respectively determine the intermediate frequency signal gain A of the proportional amplifier circuit by setting the ratio of the third resistor R3 to the fourth resistor R4 and the ratio of the sixth resistor R6 to the seventh resistor R7. m , to ensure that the signal is transmitted over long distances and that the signal is not distorted during transmission;

[0015] Step 4: The fifth-stage Sallen-Key low-pass filter amplifier circuit does not include any gain. The quality factor Q of the Sallen-Key low-pass filter amplifier circuit is determined by setting the values ​​of the second capacitor C2, the third capacitor C3, the eighth resistor R8 and the ninth resistor R9, so that its quality factor Eliminate high frequency noise; filter the voltage signal through the third operational amplifier IC3 and output the signal as the output terminal.

[0016] The third-stage and fourth-stage in-phase proportional amplifier circuits increase the bandwidth of the front-end circuit to ensure stable signal transmission. The addition of a Sallen-Key low-pass filter amplifier circuit filters out high-frequency signals and reduces the generation of high-frequency noise.

[0017] The intermediate frequency signal gain A of the third-stage proportional amplifier circuit and the fourth-stage proportional amplifier circuit m The gain of the circuit is up to 25 times, and the two-stage amplifier circuit amplifies the signal to ensure that the circuit signal has sufficient bandwidth for transmission at a higher gain. The circuit's gain of up to 25 times also ensures that weak particle signals can be captured by the circuit system.

[0018] Compared with the prior art, the present invention has the following advantages and technical effects:

[0019] The high light energy yield of the CLYC crystal of the present invention for neutrons cooperates with the detector circuit to directly convert the particle signal into a voltage signal and amplify it, thereby improving the collection efficiency of the circuit for particle signals. The front-end circuit composed of a pole-zero phase cancellation circuit, an in-phase proportional amplifier circuit and a Sallen-Key type low-pass filter circuit processes the rising edge and effectively realizes the amplification and filtering processing of the signal, ensuring that the circuit can operate stably under high gain conditions and that the Sallen-Key type low-pass filter circuit is not easy to generate high-frequency noise. At the same time, the present invention has a simple structure and is easy to implement, and can provide a certain reference value for the development of related technologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the front-end circuit based on the CLYC scintillator and SiPM detector standard output of the present invention.

[0021] Figure 2 (a) and (b) are the SiPM detector PCB diagram and the CLYC crystal physical diagram respectively.

[0022] Figure 3 Output waveform simulation image for the front-end circuit. DETAILED DESCRIPTION

[0023] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] like Figure 1 As shown, the front-end circuit of the present invention based on CLYC scintillator and SiPM detector includes a first-stage detection circuit, a second-stage pole-zero phase cancellation circuit, a third-stage in-phase proportional amplifier circuit, a fourth-stage in-phase proportional amplifier circuit and a fifth-stage Sallen-Key type low-pass filter amplifier circuit connected in sequence.

[0025] The first-stage detection circuit consists of a connected CLYC scintillator and a SiPM detector.

[0026] The pole-zero cancellation circuit of the second stage includes a first resistor R1, a first capacitor C1 and a second resistor R2. The first capacitor C1 and the first resistor R1 are connected in parallel. One end of the first resistor R1 is connected to the signal input end and the first capacitor C1, and the other end is connected to the first capacitor C1 and the +IN end of the first operational amplifier IC1 of the third-stage in-phase proportional amplifier circuit. One end of the first capacitor C1 is connected to the first resistor R1 and the signal input end, and the other end is connected to the first resistor R1 and the +IN end of the first operational amplifier IC1 of the third-stage in-phase proportional amplifier circuit. One end of the second resistor R2 is connected to the +IN end of the first operational amplifier IC1 of the third-stage in-phase proportional amplifier circuit, the first resistor R1 and the first capacitor C1, and the other end is grounded.

[0027] The third-stage in-direction proportional amplifier circuit includes a third resistor R3, a fourth resistor R4 and a first operational amplifier IC1. One end of the third resistor R3 is grounded, and the other end is connected to the fourth resistor R4 and the -IN end of the first operational amplifier IC1. One end of the fourth resistor R4 is connected to the third resistor R3 and the -IN end of the first operational amplifier IC1, and the other end is connected to the fifth resistor R5 of the fourth-stage in-direction proportional amplifier circuit and the OUT end of the first operational amplifier IC1.

[0028] The fourth-stage in-phase proportional amplifier circuit includes a fifth resistor R5, a sixth resistor R6, a seventh resistor R7 and a second operational amplifier IC2. One end of the fifth resistor R5 is connected to the OUT end of the first operational amplifier IC1 of the third-stage in-phase proportional amplifier circuit and the fourth resistor R4, and the other end is connected to the +IN end of the second operational amplifier IC2; one end of the sixth resistor R6 is respectively connected to the -IN end of the second operational amplifier IC2 and the seventh resistor R7, and the other end is grounded; one end of the seventh resistor R7 is respectively connected to the -IN end of the second operational amplifier IC2 and the sixth resistor R6, and the other end is respectively connected to the OUT end of the second operational amplifier IC2 and the eighth resistor R8 of the fifth-stage Sallen-Key type low-pass filter amplifier circuit.

[0029] The fifth-stage Sallen-Key low-pass filter amplifier circuit includes an eighth resistor R8, a ninth resistor R9, a second capacitor C2, a third capacitor C3 and a third operational amplifier IC3; one end of the eighth resistor R8 is respectively connected to the second operational amplifier IC2OUT terminal and the seventh resistor R7 of the fourth-stage in-phase proportional amplifier circuit, and the other end is respectively connected to the second capacitor C2 and the ninth resistor R9; one end of the ninth resistor R9 is respectively connected to the eighth resistor R8 and the second capacitor C2, and the other end is respectively connected to the +IN terminal of the third operational amplifier IC3 and the third capacitor C3; one end of the second capacitor C2 is respectively connected to the eighth resistor R8 and the ninth resistor R9, and the other end is connected to the OUT terminal of the third operational amplifier IC3; one end of the third capacitor C3 is respectively connected to the ninth resistor R9 and the +IN terminal of the third operational amplifier IC3, and the other end is grounded; the -IN terminal of the third operational amplifier IC3 is connected to the OUT terminal; the third operational amplifier IC3OUT terminal outputs a signal.

[0030] The second-stage pole-zero phase cancellation circuit of the circuit of the present invention processes the waveform into a unipolar signal by connecting the first resistor (R1) and the first capacitor (C1) in parallel, thereby reducing the waveform rise time; the signal then passes through the third-stage in-phase proportional amplifier circuit, and the third resistor (R3) and the fourth resistor (R4) of the feedback resistor are used to amplify the signal, and the amplification is configured to be five times. In order to ensure that the bandwidth is sufficient, the fourth-stage in-phase proportional amplifier circuit is added to further amplify the signal to ensure that the circuit has a sufficiently large bandwidth to transmit the signal, and the signal is amplified by adjusting the size of the sixth resistor (R6) and the seventh resistor (R7), and the amplification factor is configured to be five times. The fifth-stage Sallen-Key type low-pass filter amplifier circuit is further filtered and amplified, and the fifth-stage Sallen-Key type low-pass filter amplifier circuit has no gain effect. The quality factor Q of the Sallen-Key type low-pass filter circuit is determined by setting the size of the second capacitor (C2), the third capacitor (C3), the eighth resistor (R8) and the ninth resistor (R9), so that its quality factor The cut-off frequency of the Sallen-Key type low-pass filter amplifier circuit is configured to be 6MHz.

[0031] Figure 2 (a) and (b) are the SiPM detector PCB diagram and CLYC crystal physical diagram in the first-stage detection circuit of the front-end circuit, respectively. CLYC crystal is used to collect particle signals, and nine SiPMs are used to form a detection circuit to process optical signals. The detector circuit board wiring is completed on a square PCB board with a side length of 5.6 cm. A 4-layer board design is adopted, with signal routing on the top and bottom layers, the middle layer is fully paved with ground to reduce impedance, and the middle two layers are paved with power supply. The signal ground and the power ground are connected at a single point to filter out high-frequency interference that may be caused by the power ground.

[0032] The signal filtering and amplification processing method of the front-end circuit based on the CLYC scintillator and the SiPM detector of the present invention comprises the following steps:

[0033] Step 1: Particles are injected into the detection circuit composed of CLYC scintillator and SiPM detection and converted into a multiplied voltage signal.

[0034] Step 2: The voltage signal is transmitted to the second-stage pole-zero cancellation circuit to process the rising edge and reduce the rise time of the waveform;

[0035] Step 3: The third-stage proportional amplifier circuit and the fourth-stage proportional amplifier circuit realize proportional amplification of the voltage signal. The third-stage proportional amplifier circuit and the fourth-stage proportional amplifier circuit respectively determine the intermediate frequency signal gain A of the proportional amplifier circuit by setting the ratio of the third resistor R3 to the fourth resistor R4 and the ratio of the sixth resistor R6 to the seventh resistor R7. m , to ensure that the signal is transmitted over long distances and that the signal is not distorted during transmission;

[0036] Step 4: The fifth-stage Sallen-Key low-pass filter amplifier circuit does not include any gain. The quality factor Q of the Sallen-Key low-pass filter amplifier circuit is determined by setting the values ​​of the second capacitor C2, the third capacitor C3, the eighth resistor R8 and the ninth resistor R9, so that its quality factor Eliminate high frequency noise; filter the voltage signal through the third operational amplifier IC3 and output the signal as the output terminal.

[0037] like Figure 3 The simulation results of the standard output signal filter amplifier circuit are shown, showing the waveform V1 of the output signal of the SiPM equivalent circuit, the output signal waveform V2 after the pole-zero cancellation circuit, and the final output waveform V3 after amplification by two-stage positive-phase amplifiers and Sallen-Key low-pass filter processing. The gain of each stage of the positive-phase amplifier is set to 5 times, and the parameters of the Sallen-Key low-pass filter are the same as those of the fast output signal filter amplifier circuit. By comparing V1 and V2, it can be seen that although the pole-zero cancellation shortens the rising edge of the output signal of the SiPM equivalent circuit from 2μs to 200ns, the amplitude is also reduced from 230mV to 40mV; by comparing V2 and V3, it can be seen that when the gain of the two-stage positive-phase amplifier is set to 25 times, it is enough to increase the waveform amplitude after the pole-zero cancellation to about 1V. The designed Sallen-Key low-pass filter bandwidth is 5.75MHz, which does not widen the rising edge of the signal pulse.

[0038] The above content is a further elaboration of the filtering and amplification method based on the CLYC scintillator and the SiPM detector standard output front-end circuit for a specific scheme. The parts not described in detail are common knowledge to those skilled in the art.

Claims

1. A front-end circuit based on CLYC scintillator and SiPM detector, characterized in that: The front-end circuit includes a detection circuit composed of a first-stage CLYC scintillator and a SiPM detector, a second-stage pole-zero cancellation circuit, a third-stage in-phase proportional amplifier circuit, a fourth-stage in-phase proportional amplifier circuit and a fifth-stage Sallen-Key low-pass filter amplifier circuit connected in sequence; the signal forms a multiplied voltage signal through the first-stage detection circuit, the second-stage pole-zero cancellation circuit restores the fast rising edge of the pulse signal, the third-stage in-phase proportional amplifier circuit and the fourth-stage in-phase proportional amplifier circuit realize proportional amplification of the signal to ensure that the signal can be transmitted over a long distance, and the fifth-stage Sallen-Key low-pass filter amplifier circuit filters the signal to reduce the influence of high-frequency noise and outputs a voltage signal.

2. The front-end circuit based on CLYC scintillator and SiPM detector according to claim 1, characterized in that: The CLYC scintillator in the first-stage detection circuit is made of CLYC crystal material with high neutron and gamma light energy yield. Nine MicroFJ-30035-TSVs are selected to design the SiPM detector in a 3×3 SiPM array format to adapt to the size of the CLYC scintillator, ensuring that the particle signals collected by the CLYC scintillator can be fully transmitted to the SiPM detector. The SiPM detector converts the optical signal into an electrical signal and amplifies it as the input signal of the front-end circuit.

3. The front-end circuit based on CLYC scintillator and SiPM detector according to claim 1, characterized in that: The second-stage pole-zero cancellation circuit comprises a first resistor (R1), a first capacitor (C1) and a second resistor (R2); the first capacitor (C1) and the first resistor (R1) are connected in parallel; one end of the first resistor (R1) is connected to a signal input end and the first capacitor (C1), and the other end is connected to the first capacitor (C1) and a +IN end of a first operational amplifier (IC1) of a third-stage in-phase proportional amplifier circuit; one end of the first capacitor (C1) is connected to the first resistor (R1) and the signal input end, and the other end is connected to the first resistor (R1) and the +IN end of the first operational amplifier (IC1) of the third-stage in-phase proportional amplifier circuit; one end of the second resistor (R2) is connected to the +IN end of the first operational amplifier (IC1) of the third-stage in-phase proportional amplifier circuit, the first resistor (R1) and the first capacitor (C1), and the other end is grounded.

4. The front-end circuit based on CLYC scintillator and SiPM detector according to claim 1, characterized in that: The third-stage in-direction proportional amplifier circuit comprises a third resistor (R3), a fourth resistor (R4) and a first operational amplifier (IC1), one end of the third resistor (R3) is grounded, and the other end is connected to the fourth resistor (R4) and the -IN end of the first operational amplifier (IC1), one end of the fourth resistor (R4) is connected to the third resistor (R3) and the -IN end of the first operational amplifier (IC1), and the other end is connected to the fifth resistor (R5) of the fourth-stage in-direction proportional amplifier circuit and the OUT end of the first operational amplifier (IC1).

5. The front-end circuit based on CLYC scintillator and SiPM detector according to claim 1, characterized in that: The fourth-stage in-phase proportional amplifier circuit comprises a fifth resistor (R5), a sixth resistor (R6), a seventh resistor (R7) and a second operational amplifier (IC2); one end of the fifth resistor (R5) is connected to the OUT end of the first operational amplifier (IC1) of the third-stage in-phase proportional amplifier circuit and the fourth resistor (R4), and the other end is connected to the +IN end of the second operational amplifier (IC2); one end of the sixth resistor (R6) is respectively connected to the -IN end of the second operational amplifier (IC2) and the seventh resistor (R7), and the other end is grounded; one end of the seventh resistor (R7) is respectively connected to the -IN end of the second operational amplifier (IC2) and the sixth resistor (R6), and the other end is respectively connected to the OUT end of the second operational amplifier (IC2) and the eighth resistor (R8) of the fifth-stage Sallen-Key type low-pass filter amplifier circuit.

6. The front-end circuit based on CLYC scintillator and SiPM detector according to claim 1, characterized in that: The fifth-stage Sallen-Key low-pass filter amplifier circuit comprises an eighth resistor (R8), a ninth resistor (R9), a second capacitor (C2), a third capacitor (C3) and a third operational amplifier (IC3); one end of the eighth resistor (R8) is respectively connected to the OUT end of the second operational amplifier (IC2) and the seventh resistor (R7) of the fourth-stage inverse proportional amplifier circuit, and the other end is respectively connected to the second capacitor (C2) and the ninth resistor (R9); one end of the ninth resistor (R9) is respectively connected to the eighth resistor (R8) and the second capacitor (C2), and the other end is respectively connected to the One end is respectively connected to the +IN end of the third operational amplifier (IC3) and the third capacitor (C3); one end of the second capacitor (C2) is respectively connected to the eighth resistor (R8) and the ninth resistor (R9), and the other end is connected to the OUT end of the third operational amplifier (IC3); one end of the third capacitor (C3) is respectively connected to the ninth resistor (R9) and the +IN end of the third operational amplifier (IC3), and the other end is grounded; the -IN end of the third operational amplifier (IC3) is connected to the OUT end; the OUT end of the third operational amplifier (IC3) outputs a signal.

7. The signal filtering and amplifying processing method based on the front-end circuit of the CLYC scintillator and the SiPM detector according to any one of claims 1 to 6, characterized in that: The following steps are involved: Step 1: Particles are injected into the detection circuit composed of CLYC scintillator and SiPM detection and converted into a multiplied voltage signal. Step 2: The voltage signal is transmitted to the second-stage pole-zero cancellation circuit to process the rising edge and reduce the rise time of the waveform; Step 3: The third-stage in-phase proportional amplifier circuit and the fourth-stage in-phase proportional amplifier circuit realize proportional amplification of the voltage signal. The third-stage in-phase proportional amplifier circuit and the fourth-stage in-phase proportional amplifier circuit respectively determine the intermediate frequency signal gain A of the in-phase proportional amplifier circuit by setting the ratio of the third resistor (R3) to the fourth resistor (R4) and the ratio of the sixth resistor (R6) to the seventh resistor (R7). m , to ensure that the signal is transmitted over long distances and that the signal is not distorted during transmission; Step 4: The fifth-stage Sallen-Key low-pass filter amplifier circuit does not include any gain. The quality factor Q of the Sallen-Key low-pass filter amplifier circuit is determined by setting the size of the second capacitor (C2), the third capacitor (C3), the eighth resistor (R8) and the ninth resistor (R9) so that its quality factor Eliminate high frequency noise; filter the voltage signal through the third operational amplifier (IC3) and output the signal as the output terminal.

8. The signal filtering and amplifying processing method according to claim 7, characterized in that: The third-stage and fourth-stage in-phase proportional amplifier circuits increase the bandwidth of the front-end circuit to ensure stable signal transmission. The addition of a Sallen-Key low-pass filter amplifier circuit filters out high-frequency signals and reduces the generation of high-frequency noise.

9. The signal filtering and amplifying processing method according to claim 7, characterized in that: The intermediate frequency signal gain A of the third-stage proportional amplifier circuit and the fourth-stage proportional amplifier circuit m is 25.

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