A terahertz radiation signal detection system

Abstract

This invention relates to the field of terahertz wave detection technology and discloses a terahertz radiation signal detection system. In this invention, the signal receiving module includes an antenna, a feed unit, and a low-noise amplifier unit, which are connected sequentially. The local oscillator signal generation module includes a signal source, a frequency multiplier, an attenuator, and a waveguide structure, which are also connected sequentially. The low-noise amplifier unit is connected to the first input terminal of the mixer module, the waveguide structure is connected to the second input terminal of the mixer module, and the output terminal of the mixer module is connected to the signal detection module. The low-noise amplifier unit amplifies the weak terahertz radiation signal received by the antenna, thereby improving the reception capability of the terahertz radiation signal and increasing the detection sensitivity of the system. Simultaneously, the attenuator and waveguide structure are connected between the frequency multiplier and the mixer module to avoid overloading the mixer module, thus ensuring stable operation of the system and improving its stability and reliability.

Description

Technical Field

[0001] This invention relates to the field of terahertz wave detection technology, and more specifically to a terahertz radiation signal detection system. Background Technology

[0002] Currently, terahertz radiation detection systems typically employ superheterodyne receivers to detect terahertz waves. In this technology, the radiated signal received by the antenna is directly down-converted to an intermediate frequency by a mixer, amplified, and then subjected to detection, integration, and signal processing. However, this signal processing procedure suffers from insufficient lower limit for receiving weak radiated signals, resulting in limited detection sensitivity of the system. Summary of the Invention

[0003] This invention provides a terahertz radiation signal detection system to solve the problem of limited system detection sensitivity.

[0004] In a first aspect, the present invention provides a terahertz radiation signal detection system, the system comprising: The system includes a signal receiving module, a local oscillator signal generation module, a mixing module, and a signal detection module. The signal receiving module includes an antenna, a feed unit, and a low-noise amplifier unit, which are connected in sequence. The local oscillator signal generation module includes a signal source, a frequency multiplier, an attenuator, and a waveguide structure, which are connected in sequence. The low-noise amplifier unit is connected to the first input terminal of the mixer module, the waveguide structure is connected to the second input terminal of the mixer module, and the output terminal of the mixer module is connected to the signal detection module.

[0005] In one alternative implementation, the signal detection module includes a power divider unit and a multi-channel signal detection link; The input terminal of the power divider unit is connected to the output terminal of the mixer module, and the multiple output terminals of the power divider are respectively connected to the multi-channel signal detection links one by one. The power divider unit is used to divide the intermediate frequency signal output by the mixer module into multiple signals and output them to the multi-signal detection link for separate signal detection.

[0006] In one alternative implementation, the signal detection module includes six signal detection links, and the power divider unit includes a two-way power divider and a four-way power divider. The input terminals of the two-way power divider and the four-way power divider are connected to the output terminals of the mixer module, and the output terminals of the two-way power divider and the four-way power divider are connected to the multi-channel signal detection links one by one.

[0007] In one alternative implementation, the signal detection link includes an intermediate frequency conditioning circuit, a video amplification circuit, and a data acquisition unit. The intermediate frequency conditioning circuit, video amplification circuit, and data acquisition unit are connected in sequence. The intermediate frequency conditioning circuit is used to amplify and detect the intermediate frequency signal output from the power divider unit. The video amplifier circuit is used to boost the voltage amplitude of the intermediate frequency signal output. The data acquisition unit is used to sample the signals output by the multi-video amplifier circuit.

[0008] In one alternative implementation, the intermediate frequency conditioning circuit includes a first amplification unit, a second amplification unit, and a detection unit. The output of the power divider unit, the first amplification unit, the second amplification unit, and the detector unit are connected in sequence.

[0009] In one alternative implementation, the first amplification unit includes a low-pass filter and a first amplifier; The input of the low-pass filter is connected to the output of the power divider unit, and the output of the low-pass filter is connected to the input of the first amplifier. The output of the first amplifier is connected to the input of the second amplifier unit.

[0010] In one alternative implementation, the second amplification unit includes an intermediate frequency filter, an attenuator, and a second amplifier; The input terminal of the intermediate frequency filter is connected to the output terminal of the first amplification unit, and the output terminal of the intermediate frequency filter is connected to the input terminal of the attenuator. The output of the attenuator is connected to the input of the second amplifier, and the output of the second amplifier is connected to the input of the detector unit.

[0011] In one optional implementation, the video amplification circuit includes a first operational amplifier unit and a second operational amplifier unit, which are connected in sequence. The first operational amplifier unit includes a first operational amplifier, and the second operational amplifier unit includes a second operational amplifier.

[0012] In one alternative implementation, the video amplification circuit further includes an integration unit connected between the first operational amplifier unit and the second operational amplifier unit, the integration unit including an RC circuit.

[0013] In one alternative implementation, the video amplification circuit further includes an emitter follower unit, which includes a third operational amplifier.

[0014] The terahertz radiation signal detection system provided in this embodiment of the invention uses an antenna, a feed unit, and a low-noise amplifier unit to form a signal receiving module. The low-noise amplifier unit amplifies the weak terahertz radiation signal received by the antenna, thereby improving the reception capability of the terahertz radiation signal and increasing the detection sensitivity of the system. A local oscillator signal generation module is formed by a signal source, a frequency multiplier, an attenuator, and a waveguide structure. An attenuator and a waveguide structure are connected between the frequency multiplier and the mixing module to avoid overloading the mixing module, thereby ensuring the stable operation of the system and improving the stability and reliability of the system. Attached Figure Description

[0015] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the structure of a terahertz radiation signal detection system according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the signal detection module in a terahertz radiation signal detection system according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the intermediate frequency conditioning circuit in a terahertz radiation signal detection system according to an embodiment of the present invention; Figure 4 This is a circuit diagram of the video amplification circuit in a terahertz radiation signal detection system according to an embodiment of the present invention.

[0017] Explanation of reference numerals in the attached figures: 1. Signal receiving module; 2. Local oscillator signal generation module; 3. Mixer module; 4. Signal detection module; 41. Power divider unit; 42. Intermediate frequency conditioning circuit; 421. First amplification unit; 422. Second amplification unit; 423. Detector unit; 43. Video amplification circuit; 431. First operational amplifier unit; 432. Second operational amplifier unit; 433. Integrator unit; 434. Emitter follower unit; 44. Data acquisition unit. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] It is understood that before using the technical solutions disclosed in the various embodiments of the present invention, users should be informed of the types, scope of use, and usage scenarios of the personal information involved in the present invention and their authorization should be obtained in accordance with relevant laws and regulations through appropriate means.

[0020] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0021] Currently, terahertz radiation detection systems typically employ superheterodyne receivers. In this technology, the radiated signal received by the antenna is directly down-converted to an intermediate frequency (IF) by a mixer, amplified, and then subjected to detection, integration, and signal processing. However, this signal processing procedure suffers from insufficient lower limits for receiving weak radiated signals, resulting in limited system detection sensitivity. Furthermore, the mixer is usually directly connected to a frequency multiplier connected to the signal source, with the amplified local oscillator signal directly input to the mixer. This can easily lead to mixer overload, potentially damaging the entire detection system. This fixed connection method also results in a rigid system layout lacking flexibility. Additionally, the signal amplification, detection, integration, and signal processing after down-conversion to IF by the mixer suffers from insufficient filtering and amplification stages, leading to significant noise interference and further impacting the system's detection sensitivity.

[0022] To address the aforementioned technical problems, this invention provides a terahertz radiation signal detection system. The system employs an antenna, a feed unit, and a low-noise amplifier unit to form a signal receiving module. The low-noise amplifier unit amplifies the weak terahertz radiation signal received by the antenna, thereby enhancing the reception capability of the terahertz radiation signal and improving the system's detection sensitivity. A local oscillator signal generation module is constructed using a signal source, a frequency multiplier, an attenuator, and a waveguide structure. An attenuator and a waveguide structure are connected between the frequency multiplier and the mixing module to prevent overload of the mixing module, thus ensuring stable system operation and improving system stability and reliability.

[0023] According to an embodiment of the present invention, a terahertz radiation signal detection system embodiment is provided. Figure 1 This is a schematic diagram of the terahertz radiation signal detection system according to an embodiment of the present invention, as shown below. Figure 1As shown, the system includes: a signal receiving module 1, a local oscillator signal generation module 2, a mixing module 3, and a signal detection module 4. The signal receiving module 1 and the local oscillator signal generation module 2 are each connected to one input terminal of the mixing module 3, and the output terminal of the mixing module 3 is connected to the signal detection module 4. The signal receiving module 1 receives terahertz radiation signals, the local oscillator signal generation module 2 generates local oscillator signals, and the mixing module 3 mixes the terahertz radiation signal received by the signal receiving module 1 with the local oscillator signal generated by the local oscillator signal generation module 2, down-converting the terahertz radiation signal to an intermediate frequency (IF) signal, and outputting it to the signal detection module 4 for detection of the IF signal.

[0024] In embodiments of the present invention, such as Figure 1 As shown, the signal receiving module 1 includes an antenna, a feed element, and a low-noise amplifier (LNA) element, which are connected sequentially. The feed element is matched with the antenna to form a complete terahertz radiation signal receiving and collection system. The antenna receives the terahertz radiation signal in real time, the feed element collects the received terahertz radiation signal and feeds it to the LNA element, and the LNA element amplifies the terahertz radiation signal fed in by the feed element, thereby improving the terahertz radiation signal receiving capability.

[0025] In one alternative implementation, the antenna can be a 90° offset parabolic antenna or a horn antenna. Utilizing the antenna's narrow beam and high efficiency, it can effectively suppress stray radiation received from the antenna sidelobes and back lobes, as well as thermal radiation generated by the antenna's own losses. For example, brass can be used as the antenna's substrate material, with a gold-plated surface. It can also employ a 90° offset parabolic antenna with linear polarization, a beamwidth ≤2°, and a standing wave ratio ≤1.8.

[0026] In embodiments of the present invention, such as Figure 1 As shown, the local oscillator signal generation module 2 includes a signal source, a frequency multiplier, an attenuator, and a waveguide structure, which are connected sequentially. The signal source outputs a stable and high-precision specific frequency signal. The frequency multiplier multiplies the frequency signal output by the signal source. The attenuator attenuates the multiplied signal output by the frequency multiplier to protect the mixing module 3 and ensure its safe operation. The waveguide structure is used for signal transmission and flexible connection between the frequency multiplier, attenuator, and mixing module 3.

[0027] In one alternative implementation, inside the signal source, a crystal oscillator, a frequency and phase detector, a frequency divider, a low-pass filter, and a voltage-controlled oscillator form a phase-locked frequency source to ensure the frequency accuracy of the signal source output.

[0028] In one alternative implementation, the frequency multiplier can be a six-fold, eight-fold, or twelve-fold multiplier device, which can be adjusted according to the actual power requirements, and no specific limitation is made here.

[0029] In one optional implementation, the attenuator includes an attenuation circuit and a matching housing. The attenuation circuit is used to attenuate the frequency multiplier signal output by the frequency multiplier, protecting the mixer's safe operation. The model of the attenuator can be selected according to the actual circuit requirements, and no specific restrictions are imposed here.

[0030] In one optional embodiment, the waveguide structure includes an internal fine waveguide structure and a fixed housing. The internal fine waveguide structure is used for signal transmission and flexible connection between frequency multipliers, attenuators, and mixers. Through the bending design of the waveguide structure, flexible signal routing can be achieved within a limited system space, improving the flexibility of system deployment. At the same time, it can improve the integration and miniaturization of the entire detection system while ensuring signal transmission efficiency at the bend and avoiding excessive signal loss due to structural bending.

[0031] In embodiments of the present invention, such as Figure 1 As shown, the low-noise amplifier unit is connected to the first input terminal of the mixer module 3, the waveguide structure is connected to the second input terminal of the mixer module 3, and the output terminal of the mixer module 3 is connected to the signal detection module 4.

[0032] In one optional implementation, the mixing module 3 consists of a mixer, with its two input terminals connected to a low-noise amplifier unit and a waveguide structure, respectively, and its output terminal connected to a signal detection module 4.

[0033] In one alternative implementation, a Schottky diode mixer is used to form the mixing module 3 to meet the second harmonic mixing requirements.

[0034] In one alternative implementation, Figure 2 This is a schematic diagram of the structure of the signal detection module in a terahertz radiation signal detection system according to an embodiment of the present invention, as shown below. Figure 2 As shown, the signal detection module 4 includes a power divider unit 41 and a multi-channel signal detection link. The input terminal of the power divider unit 41 is connected to the output terminal of the mixer module 3, and the multiple output terminals of the power divider are respectively connected to the multi-channel signal detection link. The power divider unit 41 is used to divide the intermediate frequency signal output by the mixer module 3 into multiple signals and output them to the multi-channel signal detection link for signal detection.

[0035] In one optional implementation, the power divider unit 41 can be composed of multiple power dividers, depending on the number of signal detection links required. These power dividers divide the intermediate frequency (IF) signal output from the mixer module 3 into signals corresponding to the number of signal detection links. For example, if the signal detection module 4 includes six signal detection links, the power divider unit 41 can include a two-way power divider and a four-way power divider. The input terminals of the two-way and four-way power dividers are connected to the output terminals of the mixer module 3, respectively. The output terminals of the two-way and four-way power dividers are connected one-to-one with the multiple signal detection links. The two-way power divider divides the IF signal output from the mixer module 3 into two paths, and the four-way power divider divides the IF signal output from the mixer module 3 into four paths, thus obtaining six signals to meet the signal quantity requirements of the six signal detection links.

[0036] In one alternative implementation, the power divider can be surface-mounted, facilitating miniaturization and integration of the detection system.

[0037] In one alternative implementation, such as Figure 2 As shown, the signal detection link includes an intermediate frequency (IF) conditioning circuit 42, a video amplification circuit 43, and a data acquisition unit 44; wherein the IF conditioning circuit 42, the video amplification circuit 43, and the data acquisition unit 44 are connected in sequence. The IF conditioning circuit 42 is used to amplify and detect the IF signal output from the power divider unit 41; the video amplification circuit 43 is used to boost the voltage amplitude of the IF signal output; and the data acquisition unit 44 is used to sample the signal output from the video amplification circuit 43.

[0038] In one alternative implementation, Figure 3 This is a schematic diagram of the intermediate frequency conditioning circuit in a terahertz radiation signal detection system according to an embodiment of the present invention, as shown below. Figure 3 As shown, the intermediate frequency conditioning circuit 42 includes a first amplification unit 421, a second amplification unit 422, and a detection unit 423; wherein, the output terminal of the power divider unit 41, the first amplification unit 421, the second amplification unit 422, and the detection unit 423 are connected in sequence. The first amplification unit 421 is used to perform a first-stage power amplification of the intermediate frequency signal output by the power divider unit 41, the second amplification unit 422 is used to perform a second-stage power amplification of the intermediate frequency signal, and the detection unit 423 is used to perform detection processing on the amplified intermediate frequency signal and convert it into a voltage signal.

[0039] In one optional embodiment, the first amplification unit 421 includes a low-pass filter and a first amplifier. The input terminal of the low-pass filter is connected to the output terminal of the power divider unit 41, and the output terminal of the low-pass filter is connected to the input terminal of the first amplifier; the output terminal of the first amplifier is connected to the input terminal of the second amplification unit 422. The low-pass filter filters the intermediate frequency (IF) signal output from the power divider unit 41 to reduce noise interference; the first amplifier performs a first-stage power amplification on the IF signal, and can be an IF low-noise amplifier to achieve low-noise amplification of the IF signal.

[0040] In one optional embodiment, the second amplification unit 422 includes an intermediate frequency (IF) filter, an attenuator, and a second amplifier. The input terminal of the IF filter is connected to the output terminal of the first amplification unit 421, and the output terminal of the IF filter is connected to the input terminal of the attenuator. The output terminal of the attenuator is connected to the input terminal of the second amplifier, and the output terminal of the second amplifier is connected to the input terminal of the detection unit 423. The IF filter filters the amplified IF signal, retaining the IF signal within the required IF frequency range. The second amplifier performs a second-stage power amplification on the IF signal; it can employ an IF low-noise amplifier to achieve low-noise amplification of the IF signal. The attenuator is used to adjust the gain of its link to match the signal amplitude of the IF signal to the input threshold of the detection unit 423. The attenuator can be a 6-digit digitally controlled attenuator based on GaAs technology, with an attenuation step of 0.5 dB, a minimum attenuation of 0.5 dB, and a maximum attenuation of 31.5 dB.

[0041] In one optional embodiment, the intermediate frequency conditioning circuit 42 may further include a control unit, which controls the gain adjustment of the attenuator to ensure that the signal amplitude of the intermediate frequency signal matches the input threshold of the detection unit 423. At the same time, the control unit controls the power-on timing of the first amplifier and the second amplifier to ensure that the first amplifier and the second amplifier operate stably.

[0042] In one alternative implementation, multiple signal detection links can share a single control unit, which controls the gain adjustment of the attenuators in the intermediate frequency conditioning circuit 42 of all signal detection links, as well as the power-on timing control of the first amplifier and the second amplifier therein.

[0043] In one alternative implementation, the detection unit 423 includes a detector that linearly converts the power of the intermediate frequency signal into a DC voltage signal.

[0044] In one optional implementation, the detector is a coaxial detector with a linearity ≥0.9999, the connector housing and cavity are made of nickel-plated brass, the connector type is SMAJ-SMAK, the polarity is positive, and the characteristic impedance is 50Ω.

[0045] In one alternative implementation, a Schottky diode is used in the detector to perform a nonlinear transformation on the input intermediate frequency signal to generate a DC component and harmonic components. At the same time, a ground wave filter is used to filter out the generated high-frequency components while retaining the low-frequency and DC components.

[0046] In one optional embodiment, the video amplification circuit 43 includes a first operational amplifier unit 431 and a second operational amplifier unit 432, which are connected in sequence. The first operational amplifier unit 431 and the second operational amplifier unit 432 are both amplification circuits composed of operational amplifiers. The first operational amplifier unit 431 includes a first operational amplifier, and the second operational amplifier unit 432 includes a second operational amplifier.

[0047] In one alternative implementation, Figure 4 This is a circuit diagram of the video amplification circuit in a terahertz radiation signal detection system according to an embodiment of the present invention, as shown below. Figure 4 As shown, the first operational amplifier unit 431 consists of a first operational amplifier U1, a first resistor R1, a second resistor R2, and a third resistor R3. The first operational amplifier U1, first resistor R1, second resistor R2, and third resistor R3 form a non-inverting proportional amplifier circuit. Specifically, one end of the first resistor R1 is connected to the output signal of the intermediate frequency conditioning circuit 42, and the other end is connected to the positive input terminal of the first operational amplifier U1. One end of the second resistor R2 is connected to the output of the first operational amplifier U1, and the other end is connected to one end of the third resistor R3 and also connected to the negative input terminal of the first operational amplifier U1. The other end of the third resistor R3 is grounded.

[0048] In one alternative implementation, such as Figure 4 As shown, the second operational amplifier unit 432 consists of a second operational amplifier U2, a fourth resistor R4, a fifth resistor R5, and a sixth resistor R6. The second operational amplifier U2, the fourth resistor R4, the fifth resistor R5, and the sixth resistor R6 form a non-inverting amplifier circuit. Specifically, one end of the fourth resistor R4 is connected to the output signal of the first operational amplifier unit 431, and the other end is connected to the positive input terminal of the second operational amplifier U2. One end of the fifth resistor R5 is connected to the output of the second operational amplifier U2, and the other end is connected to one end of the sixth resistor R6 and also connected to the negative input terminal of the second operational amplifier U2. The other end of the sixth resistor R6 is grounded.

[0049] In one alternative implementation, such as Figure 4As shown, the video amplifier circuit 43 also includes an integration unit 433, which is connected between the first operational amplifier unit 431 and the second operational amplifier unit 432. The integration unit 433 includes an RC circuit consisting of a seventh resistor R7 and a capacitor C1. One end of the seventh resistor R7 is connected to the output of the first operational amplifier unit 431, i.e., the output terminal of the first operational amplifier U1, and the other end is connected to the input of the second operational amplifier unit 432, i.e., the positive input terminal of the second operational amplifier U2. One end of the capacitor C1 is connected to the other end of the seventh resistor R7, and the other end is grounded.

[0050] In one alternative implementation, such as Figure 4 As shown, the video amplifier circuit 43 also includes an emitter follower unit 434, which includes a third operational amplifier U3. The positive input terminal of the third operational amplifier is connected to the output of the second operational amplifier unit 432, i.e., the output terminal of the second operational amplifier U2, and the negative input terminal is connected to the output terminal.

[0051] In one alternative implementation, the data acquisition unit 44 includes at least an analog-to-digital converter to sample the voltage signal amplified by the video amplification circuit 43 and convert it into a digital signal for easier signal processing.

[0052] In one optional implementation, the data acquisition unit 44 may further include a digital filter, a programmable gain amplifier, an internal voltage reference source, and a clock oscillator. The digital signal obtained by the analog-to-digital converter is filtered by the digital filter, amplified by the programmable gain amplifier, and then output. The internal voltage reference source and clock oscillator provide a stable voltage supply and a reliable clock signal to the analog-to-digital converter, the digital filter, and the programmable gain amplifier.

[0053] The terahertz radiation signal detection system provided in this embodiment of the invention uses an antenna, a feed unit, and a low-noise amplifier unit to form a signal receiving module. The low-noise amplifier unit amplifies the weak terahertz radiation signal received by the antenna, thereby improving the reception capability of the terahertz radiation signal and increasing the detection sensitivity of the system. A local oscillator signal generation module is formed by a signal source, a frequency multiplier, an attenuator, and a waveguide structure. An attenuator and a waveguide structure are connected between the frequency multiplier and the mixing module to avoid overloading the mixing module, thereby ensuring the stable operation of the system and improving the stability and reliability of the system.

[0054] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A terahertz radiation signal detection system, characterized in that, The system includes: The signal receiving module (1), the local oscillator signal generation module (2), the mixing module (3), and the signal detection module (4) are included. The signal receiving module (1) includes an antenna, a feed unit, and a low-noise amplifier unit, which are connected in sequence. The local oscillator signal generation module (2) includes a signal source, a frequency multiplier, an attenuator, and a waveguide structure, wherein the signal source, the frequency multiplier, the attenuator, and the waveguide structure are connected in sequence. The low-noise amplifier unit is connected to the first input terminal of the mixer module (3), the waveguide structure is connected to the second input terminal of the mixer module (3), and the output terminal of the mixer module (3) is connected to the signal detection module (4).

2. The system according to claim 1, characterized in that, The signal detection module (4) includes a power divider unit (41) and a multi-channel signal detection link; The input terminal of the power divider unit (41) is connected to the output terminal of the mixer module (3), and the multiple output terminals of the power divider unit (41) are respectively connected to the multiple signal detection links. The power divider unit (41) is used to divide the intermediate frequency signal output by the mixer module (3) into multiple signals and output them to multiple signal detection links for signal detection.

3. The system according to claim 2, characterized in that, The signal detection module (4) includes six signal detection links, and the power divider unit (41) includes a two-way power divider and a four-way power divider. The input terminals of the two-way power divider and the four-way power divider are respectively connected to the output terminal of the mixer module (3), and the output terminals of the two-way power divider and the four-way power divider are connected to the multiple signal detection links one by one.

4. The system according to claim 2, characterized in that, The signal detection link includes an intermediate frequency conditioning circuit (42), a video amplification circuit (43), and a data acquisition unit (44). The intermediate frequency conditioning circuit (42), the video amplification circuit (43), and the data acquisition unit (44) are connected in sequence. The intermediate frequency conditioning circuit (42) is used to amplify and detect the intermediate frequency signal output by the power divider unit (41); The video amplifier circuit (43) is used to boost the voltage amplitude of the signal output by the intermediate frequency signal; The data acquisition unit (44) is used to sample the signals output by the video amplification circuit (43).

5. The system according to claim 4, characterized in that, The intermediate frequency conditioning circuit (42) includes a first amplification unit (421), a second amplification unit (422), and a detector unit (423). The output terminal of the power divider unit (41), the first amplification unit (421), the second amplification unit (422), and the detector unit (423) are connected in sequence.

6. The system according to claim 5, characterized in that, The first amplification unit (421) includes a low-pass filter and a first amplifier; The input terminal of the low-pass filter is connected to the output terminal of the power divider (41), and the output terminal of the low-pass filter is connected to the input terminal of the first amplifier. The output terminal of the first amplifier is connected to the input terminal of the second amplification unit (422).

7. The system according to claim 5, characterized in that, The second amplification unit (422) includes an intermediate frequency filter, an attenuator, and a second amplifier; The input terminal of the intermediate frequency filter is connected to the output terminal of the first amplification unit (421), and the output terminal of the intermediate frequency filter is connected to the input terminal of the attenuator. The output of the attenuator is connected to the input of the second amplifier, and the output of the second amplifier is connected to the input of the detector unit (423).

8. The system according to claim 4, characterized in that, The video amplifier circuit (43) includes a first operational amplifier unit (431) and a second operational amplifier unit (432), wherein the first operational amplifier unit (431) and the second operational amplifier unit (432) are connected in sequence; The first operational amplifier unit (431) includes a first operational amplifier, and the second operational amplifier unit (432) includes a second operational amplifier.

9. The system according to claim 8, characterized in that, The video amplification circuit (43) further includes an integration unit (433), which is connected between the first operational amplifier unit (431) and the second operational amplifier unit (432). The integration unit (433) includes an RC circuit.

10. The system according to claim 8, characterized in that, The video amplifier circuit (43) further includes an emitter follower unit (434), which includes a third operational amplifier.

Images