Aviation electromagnetic emission current measuring system

Abstract

The invention relates to the technical field of aviation electromagnetic measurement, in particular to an aviation electromagnetic emission current measurement system which comprises an emission coil, a non-inductive shunt, a signal conversion circuit, a signal amplification circuit and a signal output circuit. The non-inductive shunt is connected with the transmitting coil and is used for converting current flowing through the transmitting coil into a voltage signal; the signal conversion circuit is used for performing proportional feedback processing on the voltage signal and generating a proportional feedback signal; the signal amplification circuit is used for amplifying the proportional feedback signal and generating an amplified analog signal; and the signal output circuit is used for performing analog-to-digital conversion on the amplified analog signal and generating a digital signal. According to the invention, direct measurement is carried out based on the non-inductive shunt, the voltage drop is directly generated through the resistor, the signal delay is only influenced by circuit parasitic parameters, the response time is short, the measurement precision is higher, the overall size is smaller, and the device is suitable for airborne electromagnetic emission current detection.

Description

Technical Field

[0001] This application relates to the field of airborne electromagnetic measurement technology, and particularly to an airborne electromagnetic emission current measurement system. Background Art

[0002] In an airborne electromagnetic detection system, the accurate measurement of the emission current is a key link to obtain effective geophysical information. Under high-frequency pulse conditions, current transformers and traditional shunts in the prior art have problems such as slow response, large non-linear error, and low accuracy, and it is difficult to meet the strict requirements for the measurement accuracy of the emission current under high-altitude flight conditions.

[0003] The utility model patent with the authorization announcement number CN217133260U disclosed a kA-level emission current peak detection circuit for an airborne electromagnetic transmitter on August 5, 2022, which includes: a current sensor, an absolute value circuit, a peak sampling and holding circuit, a peak sampling synchronization pulse generation circuit, and a digital display DC voltmeter. However, it has problems such as being sensitive to electromagnetic interference of the Hall sensor, having poor linear output, and low accuracy.

[0004] The invention patent with the publication number CN116735974A disclosed a large current high-precision loop resistance measurement device and method on September 12, 2023, including a voltage acquisition module, a current sampling analog operation module, a first current sampling module, a second current sampling module, a voltage amplification module, a switch driving module, a super capacitor charging module, a super capacitor, a switch module, a voltage test line, a current test line, and a battery pack, and a large current pulsed DC source is realized by using a super capacitor. However, due to its cumbersome structure and large overall structure occupation space, it is not suitable for the detection of the emission current of airborne electromagnetic.

[0005] Therefore, it is urgent to design an airborne electromagnetic emission current measurement system. Summary of the Invention

[0006] Based on this, in view of the above technical problems, it is necessary to provide an airborne electromagnetic emission current measurement system that can directly measure based on a non-inductive shunt, is applicable to high-frequency transient current detection to obtain the magnitude of the emission current in the circuit, has higher measurement accuracy, and at the same time solves the problem in the prior art that due to the use of a non-contact measurement method, magnetic field conversion and signal processing are required, resulting in a slow response speed.

[0007] The technical solution of the present invention is as follows: An airborne electromagnetic emission current measurement system, including an emission coil, further including: A non-inductive shunt, the non-inductive shunt is connected to the emission coil and is used to convert the current flowing through the emission coil into a voltage signal; A signal conversion circuit, which is connected to the non-inductive shunt, is configured to perform proportional feedback processing on the voltage signal and generate a proportional feedback signal; A signal amplification circuit, which is connected to the signal conversion circuit, is configured to amplify the proportional feedback signal and generate an amplified analog signal; A signal output circuit, which is connected to the signal amplification circuit, is configured to perform analog-to-digital conversion on the amplified analog signal and generate a digital signal.

[0008] Optionally, the non-inductive shunt is connected in series with the transmitting coil.

[0009] Optionally, the signal conversion circuit includes a proportional feedback processing circuit and a gain amplification circuit. The proportional feedback processing circuit is connected to the non-inductive shunt, the gain amplification circuit is connected to the proportional feedback processing circuit, and the gain amplification circuit is also connected to the signal amplification circuit; the proportional feedback processing circuit is configured to proportionally feedback and amplify the voltage signal, and the gain amplification circuit is configured to perform gain amplification on the voltage signal after proportional feedback amplification and generate the proportional feedback signal.

[0010] Optionally, the proportional feedback processing circuit includes a first amplifier, a second amplifier, a first resistor, a second resistor, and a third resistor; the positive input terminal of the first amplifier is connected to the second resistor and then to the shunt, the positive input terminal of the second amplifier is connected to the shunt, the first resistor is connected to the negative input terminal of the first amplifier and then grounded, the third resistor is connected to the negative input terminal of the first amplifier and then to the gain amplification circuit; the output terminals of the first amplifier and the second amplifier are both connected to the gain amplification circuit.

[0011] Optionally, the gain amplification circuit includes a fourth resistor, a fifth resistor, a third amplifier, and a ninth resistor. The first end of the fourth resistor is connected to the output terminal of the first amplifier, the first end of the fifth resistor is connected to the output terminal of the second amplifier, the second end of the fourth resistor is connected to the second end of the fifth resistor, the second end of the fourth resistor is also connected to the negative input terminal of the third amplifier, the ninth resistor is connected to the positive input terminal of the third amplifier, and the output terminal of the third amplifier is connected to the signal amplification circuit.

[0012] Optionally, the signal amplification circuit includes a sixth resistor, a seventh resistor, a fourth amplifier, and a fifth amplifier. The first end of the sixth resistor is connected to the output end of the third amplifier, the other end of the sixth resistor is connected to the negative input end of the fourth amplifier, the seventh resistor is grounded after being connected to the positive input end of the fourth amplifier, the positive input end of the fifth amplifier is connected to the output end of the fourth amplifier, and the output end of the fifth amplifier is connected to the signal output circuit.

[0013] Optionally, the signal output circuit includes a receiver, and a signal acquisition card is provided in the receiver. The signal acquisition card is connected to the output end of the fifth amplifier and is configured to convert the signal output from the output end of the fifth amplifier into a digital signal.

[0014] Optionally, a filter circuit is further included. The filter circuit includes a filter capacitor. The first end of the filter capacitor is connected to the shunt and the positive input end of the first amplifier, and the second end of the filter capacitor is connected to the shunt and the positive input end of the second amplifier.

[0015] The technical effects achieved by the present invention are as follows: In the above-mentioned airborne electromagnetic emission current measurement system, by providing a transmitting coil, a non-inductive shunt, a signal conversion circuit, a signal amplification circuit, and a signal output circuit, the non-inductive shunt converts the current flowing through the transmitting coil into a voltage signal. Then, the signal conversion circuit performs proportional feedback processing on the voltage signal and generates a proportional feedback signal. Next, the signal amplification circuit amplifies the proportional feedback signal and generates an amplified analog signal. Finally, the signal output circuit performs analog-to-digital conversion on the amplified analog signal and generates a digital signal, realizing direct measurement based on the non-inductive shunt. A voltage drop is directly generated through the resistor, and the signal delay is only affected by the parasitic parameters of the circuit. The response time can reach the nanosecond level, which is suitable for detecting the magnitude of the emission current in the circuit by high-frequency transient current detection, with higher measurement accuracy. It solves the problem in the prior art that due to the use of a non-contact measurement method, magnetic field conversion and signal processing are required, resulting in a slow response speed. In addition, the non-inductive shunt is connected in the transmitting coil, the signal conversion circuit and the signal amplification circuit can be integrated on a small PCB board, and the signal output circuit is a receiver, so that the subsequent stage of the non-inductive shunt is connected to a small PCB board, and the output signal is directly connected to the inside of the receiver, thereby making the overall volume of the airborne electromagnetic emission current measurement system relatively small and suitable for detecting the emission current of airborne electromagnetics. Description of the Drawings

[0016] Figure 1 It is a circuit structure block diagram of the airborne electromagnetic emission current measurement system in an embodiment; Figure 2It is the circuit schematic diagram of the aviation electromagnetic emission current measurement system in an embodiment; Figure 3 It is the waveform diagram of the output signal obtained by simulation after inputting the test current signal into the aviation electromagnetic emission current measurement system in an embodiment; Figure 4 It is the output waveform diagram of the aviation electromagnetic emission current measurement system in a laboratory incubator when the temperature is controlled to be constant and there is no input; Figure 5 It is the linear error test result diagram of the aviation electromagnetic emission current measurement system in an embodiment; Figure 6 It is the temperature drift coefficient test result diagram of the aviation electromagnetic emission current measurement system in an embodiment.

[0017] Reference numerals: 100, signal conversion circuit; 110, proportional feedback processing circuit; 120, gain amplification circuit; 200, signal amplification circuit; 300, signal output circuit; 400, receiver; 500, filter circuit. Detailed implementation manners

[0018] For ease of understanding of this application, the following will describe this application more comprehensively with reference to the relevant drawings. Embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of this application more thorough and comprehensive.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs. The terms used in the description of this application herein are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0020] It can be understood that the terms "first", "second", etc. used in this application can be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, the first resistor can be called the second resistor, and similarly, the second resistor can be called the first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0021] It can be understood that "connection" in the following embodiments should be understood as "electrical connection", "communication connection", etc. if there is an electrical signal or data transfer between the connected circuits, modules, units, etc.

[0022] As used herein, the singular forms "a", "an" and "the" may also include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprises / comprising", "has / including", etc. specify the presence of the stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the related listed items.

[0023] In one embodiment, as Figure 1 - Figure 2 shown, an airborne electromagnetic emission current measurement system is provided, which includes a transmitting coil, a non-inductive shunt, a signal conversion circuit 100, a signal amplification circuit 200, and a signal output circuit 300.

[0024] The non-inductive shunt is connected to the transmitting coil and is used to convert the current flowing through the transmitting coil into a voltage signal; the signal conversion circuit 100 is connected to the non-inductive shunt and is used to perform proportional feedback processing on the voltage signal and generate a proportional feedback signal; the signal amplification circuit 200 is connected to the signal conversion circuit 100 and is used to amplify the proportional feedback signal and generate an amplified analog signal; the signal output circuit 300 is connected to the signal amplification circuit 200 and is used to perform analog-to-digital conversion on the amplified analog signal and generate a digital signal.

[0025] In this embodiment, by setting up a transmitting coil, a non-inductive shunt, a signal conversion circuit 100, a signal amplification circuit 200, and a signal output circuit 300, the non-inductive shunt converts the current flowing through the transmitting coil into a voltage signal. Then, the signal conversion circuit 100 performs proportional feedback processing on the voltage signal and generates a proportional feedback signal. Next, the signal amplification circuit 200 amplifies the proportional feedback signal and generates an amplified analog signal. Finally, the signal output circuit 300 performs analog-to-digital conversion on the amplified analog signal and generates a digital signal, realizing direct measurement based on the non-inductive shunt. A voltage drop is directly generated through a resistor, and the signal delay is only affected by circuit parasitic parameters, with a response time reaching the nanosecond level. It is suitable for detecting the magnitude of the transmitted current in a high-frequency transient current detection circuit, with higher measurement accuracy, solving the problem in the prior art that due to the use of a non-contact measurement method, magnetic field conversion and signal processing are required, resulting in a slow response speed. In addition, the non-inductive shunt is connected in the transmitting coil, and the signal conversion circuit 100 and the signal amplification circuit 200 can be integrated on a small PCB board. The signal output circuit 300 is a receiver 400, making the latter stage of the non-inductive shunt connected to a small PCB board, and the output signal is directly connected to the inside of the receiver 400, thereby making the overall volume of the airborne electromagnetic transmitted current measurement system relatively small and suitable for detecting the transmitted current of airborne electromagnetics.

[0026] In one embodiment, the non-inductive shunt is connected in series with the transmitting coil. In this embodiment, the non-inductive shunt is directly connected in series to the transmitting coil to collect the current signal in the transmitting coil. Through the optimized design of the structure of the non-inductive shunt, the influence of the phase shift between voltage and current and waveform distortion of the AC signal caused by parasitic inductance in the prior art is solved.

[0027] In one embodiment, the signal conversion circuit 100 includes a proportional feedback processing circuit 110 and a gain amplification circuit 120. The proportional feedback processing circuit 110 is connected to the non-inductive shunt, the gain amplification circuit 120 is connected to the proportional feedback processing circuit 110, and the gain amplification circuit 120 is also connected to the signal amplification circuit 200. The proportional feedback processing circuit 110 is used to proportionally feedback and amplify the voltage signal, and the gain amplification circuit 120 is used to perform gain amplification on the voltage signal after proportional feedback amplification and generate the proportional feedback signal.

[0028] In one embodiment, the proportional feedback processing circuit 110 includes a first amplifier U1, a second amplifier U2, a first resistor R1, a second resistor R2, and a third resistor R3. The positive input terminal of the first amplifier U1 is connected to the second resistor R2 and then to the shunt. The positive input terminal of the second amplifier U2 is connected to the shunt. The first resistor R1 is connected to the negative input terminal of the first amplifier U1 and then grounded. The third resistor R3 is connected to the negative input terminal of the first amplifier U1 and then to the gain amplification circuit 120. The output terminals of the first amplifier U1 and the second amplifier U2 are both connected to the gain amplification circuit 120.

[0029] Both ends of the non-inductive shunt are respectively connected to the first amplifier U1 and the second amplifier U2 of the operational amplifier. The first amplifier U1 and the second amplifier U2 are both non-inverting amplifiers, ensuring a relatively high input impedance of the circuit. The high input impedance presents a high impedance state to high-frequency noise, which can effectively attenuate high-frequency interference from the power supply, ground wire, or electromagnetic radiation, and improve the signal-to-noise ratio of the system.

[0030] In one embodiment, the proportional feedback processing circuit 110 further includes a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5, and a sixth capacitor C6. The third capacitor C3 and the fourth capacitor C4 are both connected to the first amplifier U1. The fifth capacitor C5 and the sixth capacitor C6 are both connected to the second amplifier U2. The third capacitor C3, the fourth capacitor C4, the fifth capacitor C5, and the sixth capacitor C6 serve as power supply filter capacitors, reducing the interference generated by the power supply to the first amplifier U1 and the second amplifier U2.

[0031] Specifically, by setting up a proportional feedback processing circuit with the first amplifier U1 and the second amplifier U2 as the core for proportional feedback processing, the voltages at both ends of the non-inductive shunt present a fixed ratio, solving the problem of poor linearity caused by differential processing in the prior art.

[0032] In one embodiment, the gain amplification circuit 120 includes a fourth resistor R4, a fifth resistor R5, a third amplifier U3, and a ninth resistor R9. The first end of the fourth resistor R4 is connected to the output terminal of the first amplifier U1. The first end of the fifth resistor R5 is connected to the output terminal of the second amplifier U2. The second end of the fourth resistor R4 is connected to the second end of the fifth resistor R5. The second end of the fourth resistor R4 is also connected to the negative input terminal of the third amplifier U3. The ninth resistor R9 is connected to the positive input terminal of the third amplifier U3. The output terminal of the third amplifier U3 is connected to the signal amplification circuit 200.

[0033] Furthermore, taking GND in the circuit as a reference point, the voltage across the non-inductive shunt is a value of a constant ratio, and the specific relationship is as follows: ,in, is the positive input voltage of the first amplifier U1, i.e., the upper terminal voltage of the non-inductive shunt, is the positive input voltage of the second amplifier U2, that is, the lower end voltage of the non-inductive shunt. Such a circuit structure design can greatly enhance the anti-interference ability of the circuit.

[0034] and The negative feedback between them is to feed the output signal back to the input end in reverse phase, and superimpose it with the original input signal to form a net input signal. Therefore, the amplified output mainly depends on the feedback ratio, rather than the characteristics of a single op amp or amplifier. At the same time, through the buffering of the first amplifier U1, the voltage of the shunt node is hardly lowered. And the system can automatically adjust the output to reduce the deviation caused by the non-ideal characteristics of the amplifier, temperature drift, etc.

[0035] In one embodiment, the gain amplifier circuit 120 further includes a second capacitor C2, a seventh capacitor C7 and an eighth capacitor C8. The first end of the second capacitor C2 is connected to the fifth resistor R5, the second end of the second capacitor C2 is connected to the input end of the third amplifier U3, and the second capacitor C2 is used as a phase compensation capacitor to avoid excessive oscillation in the circuit. The seventh capacitor C7 and the eighth capacitor C8 are used for filtering.

[0036] In one embodiment, the signal amplifying circuit 200 includes a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a fourth amplifier U4 and a fifth amplifier U5, the first end of the sixth resistor R6 is connected to the output end of the third amplifier U3, the other end of the sixth resistor R6 is connected to the negative input end of the fourth amplifier U4, the seventh resistor R7 is connected to the positive input end of the fourth amplifier U4 and then grounded, the positive input end of the fifth amplifier U5 is connected to the output end of the fourth amplifier U4, the output end of the fifth amplifier U5 is connected to the signal output circuit 300, and the two ends of the eighth resistor R8 are respectively connected to the negative input end and the output end of the fourth amplifier U4.

[0037] In this embodiment, the fourth amplifier U4 is used as a signal amplification module, adopts reverse amplification, and the reverse amplification circuit has only differential mode signal input. This structure effectively suppresses the influence of common mode interference (such as power supply noise, electromagnetic interference).

[0038] The circuit outputs to the NI USB-4431 acquisition card inside the receiver 400 in the signal output circuit 300. The cable length is close to one meter. When the output current is insufficient, waveform distortion is likely to occur. The fifth amplifier U5 adopts a follower structure. The main purpose is to select an operational amplifier with high load-carrying capacity. At the same time, the output impedance of the non-inverting amplifier is relatively low, which further improves the load-carrying capacity and ensures the output power.

[0039] When selecting the first amplifier U1, the second amplifier U2, the third amplifier U3, and the fourth amplifier U4, attention should be paid to the bandwidth. A suitable gain-bandwidth product is calculated by those skilled in the art. At the same time, an operational amplifier with low offset voltage needs to be selected to ensure the overall sensitivity of the circuit. For the first amplifier U1 and the second amplifier U2, special attention should also be paid to the magnitude of the input impedance to ensure the anti-interference ability.

[0040] The third resistor R3 and the first resistor R1 jointly control the amplification factor of the first amplifier U1. The sixth resistor R6 and the eighth resistor R8 jointly control the amplification factor of the fourth amplifier U4. The fifth resistor R5 and the fourth resistor R4 jointly control the amplification factor of the third amplifier U3.

[0041] In one embodiment, the signal output circuit 300 includes a receiver 400. A signal acquisition card is provided inside the receiver 400. The signal acquisition card is connected to the output end of the fifth amplifier U5 and is used to convert the signal output from the output end of the fifth amplifier U5 into a digital signal. Specifically, the output voltage is directly output from the fifth amplifier U5 to the NI USB-4431 acquisition card inside the receiver 400. The NI USB-4431 acquisition card records data, performs analog-to-digital conversion, and presents it in real time through the host.

[0042] In one embodiment, the airborne electromagnetic emission current measurement system further includes a filter circuit 500. The filter circuit 500 includes a filter capacitor C1. The first end of the filter capacitor C1 is connected to the shunt and the positive input end of the first amplifier U1. The second end of the filter capacitor C1 is connected to the shunt and the positive input end of the second amplifier U2. It should be understood that the filter capacitor C1 is connected in parallel with the non-inductive shunt and has the function of a low-pass filter, thereby effectively suppressing the high-frequency interference signals coupled on the shunt and improving the signal-to-noise ratio of the low-frequency signals.

[0043] In another embodiment, as Figure 3As shown, the test current signal input to the airborne electromagnetic emission current measurement system is a bipolar trapezoidal wave current signal with a peak value of ±500 A, a rise time of 1.3 ms, a flat top time of 5 ms, a fall time of 1.04 ms, and a frequency of 25 Hz. It can be seen that the waveform of the input current signal can be completely and truly retained at the output after being processed by the airborne electromagnetic emission current measurement system, ensuring high-fidelity transmission of the system in terms of amplitude-frequency characteristics, phase response, and linearity.

[0044] Furthermore, as Figure 4 shown, in a laboratory incubator, with the temperature controlled to be constant and in a state of no input, an 8558A eight-and-a-half-digit multimeter is used to record the output waveform of the airborne electromagnetic emission current measurement system. Within 20 minutes, the maximum output offset of the circuit does not exceed 5 μV, verifying the reliable zero-point stability of the airborne electromagnetic emission current measurement system and indicating that the low-frequency noise level of the airborne electromagnetic emission current measurement system is low.

[0045] Furthermore, as Figure 5 shown, in a laboratory incubator, with the temperature controlled to be constant, a 5730A seven-and-a-half-digit current source is used to input current through a 1 Ω sampling resistor. The input current increases by 20 mA from -500 mA to +500 mA, and an 8558A eight-and-a-half-digit multimeter is used to measure the output value of the airborne electromagnetic emission current measurement system. It can be obtained that the maximum output linear error is not greater than 0.005%.

[0046] Furthermore, as Figure 6 shown, in a laboratory incubator, the temperature of the incubator is increased by 10 °C from 0 °C to 50 °C. At the same time, at each temperature, a 5730A seven-and-a-half-digit current source is used to input currents of different magnitudes, and an 8558A eight-and-a-half-digit multimeter is used to record the output voltage. The temperature drift coefficient of each group of different currents is obtained, and the maximum temperature drift coefficient does not exceed 2.5×10 -3 % / °C, that is, 25 ppm / °C.

[0047] The above content is a further detailed description of the embodiments of the present application in combination with specific / preferred embodiments, and it cannot be determined that the specific implementation of the embodiments of the present application is only limited to these descriptions. For those of ordinary skill in the technical field to which the embodiments of the present application belong, without departing from the concept of the embodiments of the present application, they can also make several substitutions or modifications to these described embodiments, and these substitution or modification methods should all be regarded as belonging to the protection scope of the embodiments of the present application. In the description of this specification, the description with reference to terms such as "an embodiment", "some embodiments", "preferred embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0048] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this application.

[0049] The above embodiments only express several implementation manners of the present application, and their descriptions are relatively specific and detailed, but they cannot be understood as a limitation to the patent scope of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several deformations and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of the present application, and they should all be covered within the scope of the claims and the description of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions that fall within the scope of the claims.

Claims

1. An aviation electromagnetic launch current measurement system, including a launch coil, characterized in that, Further included are: A non-inductive shunt, which is connected to the transmitting coil and is used to convert the current flowing through the transmitting coil into a voltage signal; A signal conversion circuit, which is connected to the non-inductive shunt and is used to perform proportional feedback processing on the voltage signal and generate a proportional feedback signal; A signal amplification circuit, which is connected to the signal conversion circuit and is used to amplify the proportional feedback signal and generate an amplified analog signal; A signal output circuit, which is connected to the signal amplification circuit and is used to perform analog-to-digital conversion on the amplified analog signal and generate a digital signal.

2. The aviation electromagnetic emission current measurement system according to claim 1, wherein The non-inductive shunt is connected in series with the transmitting coil.

3. The aviation electromagnetic emission current measurement system according to claim 1, characterized in that The signal conversion circuit includes a proportional feedback processing circuit and a gain amplification circuit. The proportional feedback processing circuit is connected to the non-inductive shunt, the gain amplification circuit is connected to the proportional feedback processing circuit, and the gain amplification circuit is also connected to the signal amplification circuit; the proportional feedback processing circuit is used to proportionally feedback and amplify the voltage signal, and the gain amplification circuit is used to perform gain amplification on the voltage signal after proportional feedback amplification and generate the proportional feedback signal.

4. The airborne electromagnetic emission current measurement system according to claim 2, characterized in that, The proportional feedback processing circuit includes a first amplifier, a second amplifier, a first resistor, a second resistor, and a third resistor; the positive input terminal of the first amplifier is connected to the second resistor and then to the shunt, the positive input terminal of the second amplifier is connected to the shunt, the first resistor is connected to the negative input terminal of the first amplifier and then grounded, the third resistor is connected to the negative input terminal of the first amplifier and then to the gain amplification circuit; the output terminals of the first amplifier and the second amplifier are both connected to the gain amplification circuit.

5. The airborne electromagnetic emission current measurement system according to claim 4, characterized in that The gain amplification circuit includes a fourth resistor, a fifth resistor, a third amplifier, and a ninth resistor. The first end of the fourth resistor is connected to the output terminal of the first amplifier, the first end of the fifth resistor is connected to the output terminal of the second amplifier, the second end of the fourth resistor is connected to the second end of the fifth resistor, the second end of the fourth resistor is also connected to the negative input terminal of the third amplifier, the ninth resistor is connected to the positive input terminal of the third amplifier, and the output terminal of the third amplifier is connected to the signal amplification circuit.

6. The airborne electromagnetic emission current measurement system according to claim 5, characterized in that, The signal amplification circuit includes a sixth resistor, a seventh resistor, a fourth amplifier, and a fifth amplifier. The first end of the sixth resistor is connected to the output terminal of the third amplifier, the other end of the sixth resistor is connected to the negative input terminal of the fourth amplifier, the seventh resistor is connected to the positive input terminal of the fourth amplifier and then grounded, the positive input terminal of the fifth amplifier is connected to the output terminal of the fourth amplifier, and the output terminal of the fifth amplifier is connected to the signal output circuit.

7. The airborne electromagnetic emission current measurement system according to claim 6, characterized in that, The signal output circuit includes a receiver, and a signal acquisition card is provided in the receiver. The signal acquisition card is connected to the output terminal of the fifth amplifier and is used to convert the signal output from the output terminal of the fifth amplifier into a digital signal.

8. The airborne electromagnetic emission current measurement system according to claim 4, characterized in that, It further includes a filter circuit, the filter circuit includes a filter capacitor, a first end of the filter capacitor is connected to the shunt and a positive input terminal of the first amplifier, and a second end of the filter capacitor is connected to the shunt and a positive input terminal of the second amplifier.

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