Large current injection equivalent electromagnetic radiation effect test calibration method and system

Abstract

The present invention provides a large current injection equivalent electromagnetic radiation effect test calibration method and system, using a radiation source to irradiate a parallel two-wire cable under a first preset field strength, recording a first value; maintaining irradiation, connecting a current injection probe to a preset load and then inserting it into the cable, recording a second value; calculating the test error according to the first value and the second value; stopping irradiation, adjusting the injection power after connecting the probe to a signal source, and determining a first injection power that is the same as the first value; determining the linear relationship between the signal source and the radiation source according to the first preset field strength, the test error and the first injection power; performing a general high field strength extrapolation test according to the linear relationship, and completing the electromagnetic radiation effect test process. By considering the influence of the current injection probe access on the equivalent radiation effect test during the experiment, the experimental error caused by the current injection probe access can be effectively reduced, thereby performing a calibration process and completing the equivalent electromagnetic radiation effect test more accurately.

Description

Technical Field

[0001] The invention belongs to the technical field of environmental monitoring, and in particular relates to a large current injection equivalent electromagnetic radiation effect test calibration method and system. Background Art

[0002] High-power radio frequency electromagnetic radiation fields have brought the most severe challenges to weapons and equipment, integrated electronic information systems, etc. In order to exchange information and transmit power, various devices or subsystems are often interconnected through different types of cables, resulting in a high probability that the weak link of electromagnetic protection will appear in the cable coupling channel. Multi-core cables are currently the most widely used type of cables in weapons and equipment, so it is very important to test and assess the electromagnetic radiation effects of multi-core cable coupling channels of weapons and equipment.

[0003] At present, the most mature electromagnetic radiation effect test method is the large current injection method. However, this method is mainly used to study the conduction sensitivity. When applied to equivalent replacement of strong field electromagnetic radiation effect test, there are still problems such as unreasonable selection of equivalent basis, difficulty in extrapolation test, and large test error when applied to nonlinear systems. Summary of the invention

[0004] In view of this, the present invention provides a large current injection equivalent electromagnetic radiation effect test correction method and system, aiming to solve the problem of large errors in strong field electromagnetic radiation effect tests under large current injection methods in the prior art.

[0005] A first aspect of an embodiment of the present invention provides a large current injection equivalent electromagnetic radiation effect test calibration method, comprising:

[0006] Under a first preset field strength, using a radiation source to irradiate the parallel two-wire cable, and recording a first value of the spectrum analyzer;

[0007] Maintaining the radiation source irradiation, injecting current into the probe, connecting the probe to the preset load, and then inserting the probe into the cable, and recording the second value of the spectrum analyzer;

[0008] Calculating a test error based on the first value and the second value;

[0009] Stop irradiation from the radiation source, inject current into the probe and connect it to the signal source, then adjust the injection power of the signal source to determine a first injection power that is the same as the first value;

[0010] Determining a linear relationship between a signal source and a radiation source according to a first preset field strength, a test error, and a first injection power;

[0011] A general high field strength extrapolation test is carried out based on the linear relationship to complete the electromagnetic radiation effect test process.

[0012] A second aspect of an embodiment of the present invention provides an equivalent electromagnetic radiation effect test system, characterized in that it includes: a coaxial load, a parallel two-wire cable, an antenna, a signal source, a current injection probe, a matching load, a through load, a signal conversion module and a receiver;

[0013] The coaxial load, parallel two-wire cable, antenna, current injection probe, matching load, and through-type load are all set in the microwave darkroom;

[0014] The coaxial load is connected to the first end of the parallel two-wire cable; the through-type load is connected to the second end of the parallel two-wire cable; and the signal conversion module is used to connect the through-type load arranged in the microwave darkroom with the receiver outside the microwave darkroom.

[0015] The large current injection equivalent electromagnetic radiation effect test calibration method and system provided by the embodiment of the present invention, under the first preset field strength, use a radiation source to irradiate the parallel two-wire cable, record the first value of the spectrum analyzer; maintain the radiation source irradiation, connect the current injection probe to the preset load and then insert it into the cable, record the second value of the spectrum analyzer; calculate the test error according to the first value and the second value; stop the radiation source irradiation, after the current injection probe is connected to the signal source, adjust the injection power of the signal source, and determine the first injection power that is the same as the first value; determine the linear relationship between the signal source and the radiation source according to the first preset field strength, the test error and the first injection power; perform a general high field strength extrapolation test according to the linear relationship to complete the electromagnetic radiation effect test process. By considering the influence of the current injection probe access on the equivalent radiation effect test during the experiment, the experimental error caused by the current injection probe access can be effectively reduced, thereby performing the calibration process and completing the equivalent electromagnetic radiation effect test more accurately. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0017] Figure 1 is a schematic diagram of the configuration of a parallel double-line irradiation experiment provided by an embodiment of the present invention;

[0018] Figure 2 is a schematic diagram of the configuration of a parallel double-line injection experiment provided by an embodiment of the present invention;

[0019] Figure 3 It is a schematic diagram of a simplified model of parallel double lines;

[0020] Figure 4 is a schematic diagram of the injection network model;

[0021] Figure 5 It is a schematic diagram of the irradiation network model;

[0022] Figure 6 It is the implementation flow chart of the traditional equivalent electromagnetic radiation effect test;

[0023] Figure 7 It is a flow chart for implementing a large current injection equivalent electromagnetic radiation effect test correction method provided by an embodiment of the present invention;

[0024] Figure 8 is the test curve before parallel double-line BCI correction;

[0025] Fig. 9 It is the test curve after parallel double-line BCI correction;

[0026] Fig.10 It is the test curve before parallel two-line BCI correction when the EUT impedance changes;

[0027] Fig.11 It is the test curve after parallel two-line BCI correction when the EUT impedance changes. DETAILED DESCRIPTION

[0028] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0029] Figure 1 It is a schematic diagram of the configuration of a parallel double-line irradiation experiment provided by an embodiment of the present invention. Figure 2 FIG. 1 is a schematic diagram of the configuration of a parallel double-line injection experiment provided by an embodiment of the present invention. Figure 1 and Figure 2 As shown, in some embodiments, an equivalent electromagnetic radiation effect test system includes: a coaxial load 11, a parallel two-wire cable 12, an antenna 13, a signal source 14, a current injection probe 15, a matching load 16, a through load 17, a signal conversion module 18 and a receiver 19.

[0030] The coaxial load 11, the parallel two-wire cable 12, the antenna 13, the current injection probe 15, the matching load 16, and the through-type load 17 are all arranged in a microwave darkroom.

[0031] The coaxial load 11 is connected to the first end of the parallel two-wire cable 12; the through-type load 17 is connected to the second end of the parallel two-wire cable 12; and the signal conversion module 18 is used to connect the through-type load 17 set in the microwave darkroom with the receiver 19 outside the microwave darkroom.

[0032] The signal conversion module 18 includes two photoelectric conversion modules, which are respectively connected to the through-type load 17 and the receiver 19, and the two photoelectric conversion modules are connected via optical fibers. The receiver 19 can be a test device, a spectrum analyzer, etc., which is not limited here.

[0033] The specific test system setting can be as follows: place a 2m long parallel double wire on a horizontal table with a height of 1m, connect a coaxial load with an impedance value of 50Ω at the left end of the parallel double wire, and connect a through-type load at the right end in turn. During irradiation, place a pair of biconical antennas as a radiation excitation source at a distance of 0.6m from the parallel double wire. During injection, insert a current probe into the right end of the parallel double wire, and connect the probe end to the injection excitation source (signal source). In order to better monitor the response of the through-type load at the right end, connect an optoelectronic conversion module to the right end of the through-type load to convert the electrical signal into an optical signal. Connect another optoelectronic conversion module through an optical fiber, and then connect it to a receiver (spectrum analyzer).

[0034] In some embodiments, when irradiating the parallel two-wire cable, the signal source and the antenna in the microwave darkroom form a radiation source, and the signal source outputs power corresponding to the first preset field strength or the second preset field strength to complete the irradiation process;

[0035] When current is injected into the parallel two-wire cable, the signal source is connected to the current injection probe in the microwave darkroom, and the signal source outputs the first injection power or the second injection power to complete the current injection process.

[0036] In some embodiments, the radiation source remains in operation, and the current injection probe is connected to the matching load and then snapped into the cable to complete the error test process.

[0037] For interconnected systems, the basis for engineering equivalence between injection and irradiation tests is that the effects of the equipment under test (EUT) are the same under the two conditions. In order to analyze this equivalence problem theoretically, the conditions for injection and irradiation equivalence are analyzed based on the equal port response of the EUT, and then the analysis model for injection and irradiation equivalence is established through theoretical deduction.

[0038] Figure 3 is a schematic diagram of a simplified model of parallel double lines. Figure 3As shown in the figure, for a parallel double line with a certain height H from the ground and a length of L, the probe is stuck at any position of the parallel double line. The length of the parallel double line on the left end of the probe is L1, and the length of the parallel double line on the right end of the probe is L2. Since the width of the probe is much smaller than the length of the parallel double line in terms of linearity, the width of the probe can be ignored.

[0039] Since the differential mode response of the EUT is being explored, according to the definition of the common differential mode, each matrix can be written under the condition of the modal domain. Through the transformation of the modal domain, each transmission matrix can be written in the form of the modal domain. It can be written as the modal domain matrix Z of the left and right devices L , Z R :

[0040]

[0041]

[0042] Among them, Z G,L and Z G,R are the ground impedances of the left and right terminals of the cable, Z DL and Z DR are the differential mode impedances of the devices at the left and right ends of the cable respectively. L and δ R They are the unbalanced degree of impedance of the equipment at the left and right ends respectively.

[0043] It can be concluded that:

[0044]

[0045] Among them, Z C is the parallel two-line modal domain matrix, Z CM is the common mode characteristic impedance of the parallel two-line, Z DM It is the differential characteristic impedance of parallel two lines.

[0046]

[0047]

[0048] Among them, Ф W (L1) is the parallel double-line transmission matrix in the modal domain on the left side of the probe. The length of the parallel double line is L1, Ф W (L2) is the parallel double-line transmission matrix in the modal domain on the right side of the probe, and the length of the parallel double line is L2.1 2×2 is the second-order unit matrix, and γ0 is the propagation constant.

[0049]

[0050]

[0051]

[0052] Among them, Ф P is the probe modal domain matrix, Z P is the modal domain probe impedance matrix, Y P is the modal domain probe admittance matrix. ZCMP is the common mode impedance of the probe coupled to the parallel double lines, and ZDMP is the differential mode impedance of the probe coupled to the parallel double lines. YCMP is the common mode admittance of the probe coupled to the parallel double lines, and YDMP is the differential mode admittance of the probe coupled to the parallel double lines.

[0053] F P =(V S -Y P ·V S ) T (9)

[0054] V S =V S (1 0) T (10)

[0055] Among them, F P is the source vector, V S is the injection source vector, V S The injection probe is applied to the common-mode voltage on the parallel pair of wires.

[0056] Under the above-mentioned parallel two-line model, the ETU response derivation is performed under injection conditions and irradiation conditions respectively.

[0057] Figure 4 is a schematic diagram of the injection network model. Figure 4 As shown, the EUT response of the injection condition is derived as follows:

[0058] The differential mode response of the right-end EUT in the BCI (Bulk current injection) method can be solved by the link parameter method. The subscripts 1 and 2 represent the two parallel cables, and the superscript (i) represents the injection condition. I represents the current, and V represents the voltage of the two cables to ground. According to the calculation method of the modal domain, the response matrix of the right-end EUT can be written as:

[0059]

[0060] V (i) (L) = Z R I (i) (L) (12)

[0061] V (i) (0) = -Z L I (i) (0) (13)

[0062] Among them, the specific expressions of M1 and N1 are as follows:

[0063]

[0064]

[0065] in, is the response matrix of the EUT on the right side of the injection method in the modal domain, is the response matrix of the left-end test device of the injection method in the modal domain. Substituting it into the solution, we can get:

[0066]

[0067] The same idea as the theoretical derivation model of the injection method, the solution model of the EUT response during irradiation can also use the link parameter method. The injection probe divides the parallel double line into two sections. Since only the response of the left and right terminals is concerned, the distributed source on the cable caused by irradiation in the Agrawal model can be converted into a lumped source at both ends of the cable, V SL1 、V SR1 The lumped source vector composed of W (L1) The source vector F on the left W1 Similarly, V SL2 、V SR2 The lumped source vector composed of W (L2) The source vector F on the left W2 .

[0068] Figure 5 is a schematic diagram of the irradiation network model. Figure 5 As shown, the derivation of the EUT response under irradiation conditions is as follows:

[0069] F W1 =(V SL1 -cosh(γ0L1)V SR1 -sinh(γ0L1)Z C -1 V SR1 ) T (17)

[0070] F W2 =(V SL2 -cosh(γ0L2)V SR2 -sinh(γ0L2)Z C -1 V SR2 ) T (18)

[0071]

[0072] Since the field line coupling process is a linear process, the source S1, S7 and the radiation field strength are linearly related. Therefore, V SL1 、V SR1 、V SL2 、V SR2 It is linearly related to the radiation field strength.

[0073] Therefore, the response calculation matrix equation of the right-hand EUT during irradiation is:

[0074]

[0075] V (r) (L) = Z R I (r) (L) (21)

[0076] V (r) (0) = -Z L I (r) (0) (22)

[0077] The specific expressions of M2 and N2 are as follows, and the superscript (r) indicates the irradiation conditions:

[0078]

[0079]

[0080] in, is the response matrix of the right-hand EUT when irradiated in the modal domain, is the response matrix of the left test device when irradiated in the modal domain.

[0081] Through the above derivation, the response matrix of the EUT on the right is:

[0082]

[0083] In order to explore the corresponding relationship between the injection voltage during injection and the excitation source during irradiation, the equal differential mode voltage of the right-end EUT is used as the equivalent criterion. That is:

[0084]

[0085] After calculation, we can get:

[0086] V S =X1X2 (27)

[0087] Among them, the expressions of X1 and X2 are as follows:

[0088]

[0089] X1=4g 12 h21 Z DL -g 11 h 22 Z DL +2g 11 h 21 δ L Z DL -2g 12 h 22 δ L Z DL -g 12 g 21 Z DL 2 (29)

[0090] +g 11 g 22 Z DL 2 +g 12 g 21 δ L 2 Z DL 2 -g 11 g 22 δ L 2 Z DL 2 +h 11 (4h 22 -4g 22 Z DL -2g 21 δ L Z DL )

[0091] -4g 11 h 22 Z G,L -4g 12 g 21 Z DL Z G,L +4g 11 g 22 Z DL Z G,L +h 12 (-4h 21 +g 21 Z D1 +2g 22 δ L Z DL +4g 21 Z G,L )

[0092] Observe the above formula, X1 and X2 are independent of the parameters of the device under test on the right, while the parameters in E, F, G, and H represent the physical quantities of the parallel double wires. Therefore, the excitation voltage source V of the injection method can be determined. S It is linearly related to the source vector S1 and S7 during irradiation. The expressions of E, F, G, and H are as follows:

[0093]

[0094]

[0095]

[0096]

[0097] Substituting the parameters of the actual model, we get:

[0098] V S =X3(X5+X6) (34)

[0099] Among them, X4 is an element of X5 and X6.

[0100]

[0101]

[0102]

[0103] To simplify the expression form:

[0104]

[0105] Among them, H PL It is the transfer function of the parallel two-wire coupling channel. The transfer function is determined by the impedance characteristics of the parallel two-wire itself, the impedance characteristics of the probe coupled to the cable, the admittance characteristics, and the impedance characteristics of the left transmitter, and has nothing to do with the impedance characteristics of the EUT on the right. In engineering, the transmitter is usually in a low-resistance state, and its impedance is often relatively stable. Therefore, it can be considered that the equivalent correspondence is linear. Through theoretical derivation, the three problems of EUT being a nonlinear system, how to obtain the injection excitation voltage source, and the lack of basis for directly linearly extrapolating the excitation source to simulate high-field intensity irradiation tests can be solved.

[0106] For question 1, the correspondence between the size of the injected excitation voltage source and the irradiation field strength in the BCI method is only related to the impedance characteristics of the parallel double wires themselves, the impedance characteristics of the probe coupled to the cable, and the impedance characteristics of the transmitting end at the left end of the cable, and has nothing to do with the impedance characteristics of the EUT at the right end. In other words, this correspondence is also applicable to nonlinear systems.

[0107] For question 2, the equivalent correspondence is independent of the impedance characteristics of the EUT, so the equivalent injection excitation source can be obtained by removing the EUT or monitoring the cable terminal response in parallel. Under the irradiation and injection conditions, adjust the amplitude of the injection excitation voltage source so that the cable terminal response under these two conditions is consistent. In this way, the equivalent injection excitation voltage source has been obtained, and the corresponding relationship with the irradiation field strength has been established.

[0108] For question 3, a preliminary test of equivalent irradiation can be conducted at low field strength to find the corresponding relationship between the injection excitation source and the irradiation field strength. Since the radiation field strength is not defined in the equivalent corresponding relationship, after the low field strength is extrapolated to the high field strength, the extrapolated corresponding relationship is still linear, and the irradiation effect test under high field strength can be simulated by the method of extrapolating the excitation source.

[0109] Therefore, in engineering, the equivalent corresponding relationship between the injection excitation voltage source and the irradiation field strength is obtained under low field strength conditions, and the injection excitation source is linearly extrapolated under high field strength, so that the BCI equivalent high-field irradiation effect test can be carried out.

[0110] To carry out strong field radiation equivalence test, it is first necessary to obtain the response of cable terminals under both radiation and injection conditions.

[0111] There are many types of EUTs at present. If the EUT has an output port that can be directly monitored, then the spectrum analyzer can be connected to the output port to directly monitor the response. However, most devices do not have direct output ports, and it is difficult to measure their response under certain conditions, which makes it very difficult to establish a linear relationship of injected equivalent irradiation by directly monitoring the port response under low field strength. Therefore, it is necessary to find a solution.

[0112] Since the relationship between the injection source and the radiation field strength has nothing to do with the impedance of the EUT, no matter what device is connected to the cable terminal, it does not affect the corresponding relationship between the injection excitation voltage source and the irradiation field strength. In order to facilitate monitoring, in actual projects, the cable can be disconnected to directly test the terminal response of the cable, or the EUT can be turned off and a set of line pairs can be connected in parallel at the cable terminal.

[0113] Next, we need to obtain an equivalent injection excitation voltage source. The purpose of the equivalent test is always to make the responses monitored under irradiation and injection conditions equal. In order to simplify the operation steps and calculation process, the output power of the injection excitation voltage source can be directly adjusted so that the response of the cable terminal under injection conditions is consistent with the response under irradiation conditions. In this way, the injection excitation voltage source is the equivalent excitation source calculated by the irradiation field intensity. The equivalent correspondence relationship is established.

[0114] After obtaining the equivalent injection excitation source, an extrapolation test is required. The above formula does not define the size of the irradiation field strength E0, which means that the corresponding relationship between the injection excitation voltage source and the irradiation field strength is always linear regardless of low or high field strength. In this way, in high field strength, the irradiation and injection excitation at the external port of the EUT are consistent. The changes in the impedance of the EUT are also consistent, and the response is also consistent.

[0115] The linear equivalent correspondence is very important, which means that linear extrapolation can be performed during the equivalent field irradiation test. This is also the reason why the equivalent correspondence established under low field strength conditions is used. High field strength conditions are not easy to achieve, but low field strength conditions are obviously very easy to achieve.

[0116] Assume that the injection excitation voltage source that establishes an equivalent corresponding relationship under low field strength conditions is V S0 , the irradiation field strength is E0, and its simplified expression is V S0 =k×E0. In the effect test of EUT, the critical field strength of EUT is set as E1. However, it is very difficult to achieve a strong electromagnetic field E1 in a large space. Therefore, the equivalent injection excitation voltage source V can be converted. S1 =k×E1. Because the equivalent correspondence is linear, k remains unchanged during extrapolation.

[0117] The traditional equivalent electromagnetic radiation effect test is carried out based on the above theoretical analysis. Figure 6 This is the implementation flow chart of the traditional equivalent electromagnetic radiation effect test. Figure 6 As shown, the test method for the equivalent irradiation effect of parallel two-line coupled continuous wave BCI is as follows:

[0118] (1) Prepare for the test. Keep the equipment at the left end of the interconnected transmission line unchanged, remove the EUT at the right end of the parallel double line, and directly monitor the response at the right end of the cable. Alternatively, turn off the EUT, connect a set of line pairs in parallel at the cable terminal, and then connect a spectrum analyzer to monitor the response at the cable terminal.

[0119] (2) Conduct a low-field strength pre-experiment and obtain the response of the right end of the cable under a known low-field strength irradiation condition. Then, adjust the injection excitation voltage source under the injection condition so that the response of the cable terminal during injection excitation is the same as the response of the cable terminal during irradiation excitation, thereby establishing a linear relationship between the injection excitation voltage source and the radiation field strength.

[0120] (3) Perform a high field strength extrapolation experiment. Based on the linear relationship obtained previously, the excitation source is linearly extrapolated. At the same time, the right end of the parallel double line is connected back to the original EUT. At this time, the response of the BCI excitation to the EUT is the response of the irradiation field strength to the EUT through the same linear extrapolation. The BCI equivalent irradiation test under strong field conditions is completed.

[0121] Through the above analysis and verification, it can be known that in the BCI equivalent strong field irradiation test of the parallel two-wire coupling channel, when the irradiation conditions are met, a current injection probe needs to be inserted into the cable. Only in this way can the BCI strict equivalent strong field irradiation test be guaranteed. However, in actual engineering, the irradiation conditions often do not require the current injection probe to be inserted into the cable. Changes in the current injection probe will cause errors in the equivalent test to a certain extent, so the present invention has made the following improvements:

[0122] Figure 7 1 is a flow chart of the implementation of the large current injection equivalent electromagnetic radiation effect test calibration method provided by the embodiment of the present invention. Figure 7 As shown, in some embodiments, a large current injection equivalent electromagnetic radiation effect test calibration method includes:

[0123] S710, irradiating the parallel two-wire cable using a radiation source under a first preset field strength, and recording a first value of the spectrum analyzer;

[0124] S720, maintaining the radiation source irradiation, injecting current into the probe, connecting the probe to a preset load, and then inserting the probe into the cable, and recording a second value of the spectrum analyzer;

[0125] S730, calculating a test error according to the first value and the second value;

[0126] S740, stopping the radiation source from irradiating, injecting a current into the probe and connecting it to the signal source, adjusting the injection power of the signal source, and determining a first injection power that is the same as the first value;

[0127] S750, determining a linear relationship between the signal source and the radiation source according to the first preset field strength, the test error and the first injection power;

[0128] S760, conducts a general high field strength extrapolation test based on the linear relationship to complete the electromagnetic radiation effect test process.

[0129] The key to the correction technology is to obtain the response difference between the cable terminal with and without the probe under irradiation conditions. When the equivalent relationship between the injection excitation voltage source and the irradiation field strength is established at low field strength, the injection power can be based on the original equivalent irradiation power with the probe to compensate for the difference in the response of the cable with or without the probe under irradiation conditions. Therefore, the present invention records the first value and the second value of the spectrum analyzer before and after the current injection probe is connected under irradiation, and the difference between the two recorded values ​​can be obtained to obtain the impact of the current injection probe connection on the equivalent test.

[0130] The size of the preset load connected to the current injection probe is determined by the equivalent impedance when the current injection probe is connected to the signal source, for example, it may be 50Ω.

[0131] In some embodiments, S750 includes:

[0132]

[0133] Among them, V S0 is the first injection power, Δ is the experimental error, and E0 is the first preset field strength.

[0134] In the embodiment of the present invention, under low field strength conditions, the preliminary steps are the same as the conventional low field strength pre-test steps, except that, after the original equivalent correspondence between the injection excitation voltage source and the irradiation field strength is established, the current probe is removed under irradiation conditions. The response of the cable terminal at this time is monitored, and the difference Δ(dB) with the terminal response with the current probe under irradiation conditions is calculated. Then, this difference Δ(dB) is added to the injected power. The corrected equivalent correspondence is established.

[0135] In some embodiments, before S730, the method further includes: obtaining the frequency of the current injection probe; and determining whether to execute the step of calculating the test error based on the first value and the second value according to the frequency of the current injection probe.

[0136] In some embodiments, determining whether to execute the step of calculating the test error based on the first value and the second value is performed based on the frequency of the current injection probe, including: when the frequency of the current injection probe is greater than the preset frequency, executing the step of calculating the test error based on the first value and the second value.

[0137] In some embodiments, determining whether to execute the step of calculating the test error according to the first value and the second value is performed according to the frequency of the current injection probe, including: when the frequency of the current injection probe is not greater than the preset frequency, not executing the step of calculating the test error according to the first value and the second value, and instead executing the following steps: stopping the radiation source irradiation, connecting the current injection probe to the signal source, adjusting the injection power of the signal source, and determining a first injection power that is the same as the first value; determining the linear relationship between the signal source and the radiation source according to the first preset field strength and the first injection power; and performing a general high field strength extrapolation test according to the linear relationship to complete the electromagnetic radiation effect test process.

[0138] In the embodiment of the present invention, it is found through preliminary tests that the magnitude of the correction power of the irradiation with or without the probe is as shown in Table 1:

[0139] Table 1 Correction power of irradiation with and without probe

[0140]

[0141] Figure 8 It is the test curve before the parallel double-line BCI correction. Fig. 9This is the test curve after parallel dual-line BCI calibration. The horizontal axis is the frequency, and the vertical axis is the response of the device under test. Fig.10 It is the test curve before parallel two-line BCI correction when the EUT impedance changes. Fig.11 This is the test curve after parallel double-line BCI correction when the EUT impedance changes. The horizontal axis is the frequency, and the vertical axis is the relative error. As shown in Table 1, Figure 8 , Fig. 9 , Fig.10 and Fig.11 As shown, the effect of BCI correction in the parallel two-wire coupling channel is significantly better than the result without correction, and the result after correction is closer to the situation of irradiation without probe in actual engineering. However, in the results before correction, the errors of 600MHz and 700MHz are very large. The performance of the current probe may decline at a frequency higher than 400MHz. It can also be seen from the corrected power value that the influence of the probe after 400MHz will increase, resulting in a large error in the terminal response of the cable with or without the probe under irradiation conditions. However, looking at the data before 400MHz, most of the errors before correction are less than 6dB, which also meets the actual needs of the project. Therefore, when the test error requirements are not very strict, the effect test of the frequency below 400MHz does not need to be corrected. However, if a frequency above 400MHz is to be performed, it is recommended to perform correction due to the existence of unstable frequencies. Therefore, the present invention uses 400MHz as the preset frequency to determine whether the test error needs to be calculated, thereby reducing the amount of calculation of the test as much as possible.

[0142] In some embodiments, S760 includes: obtaining a second preset field strength required to be verified in a high field strength extrapolation test; wherein the second preset field strength is greater than the first preset field strength; under the second preset field strength, using a radiation source to irradiate a parallel two-wire cable, and recording a third value of the spectrum analyzer; calculating a second injection power based on a linear relationship; stopping the radiation source from irradiating, injecting current into the probe, connecting it to the signal source, and then inserting it into the cable, adjusting the injection power of the signal source to the second injection power, and recording a fourth value of the spectrum analyzer; determining the differential mode response of the high field strength extrapolation test based on the third and fourth values, and completing the electromagnetic radiation effect test process.

[0143] In some embodiments, the differential mode response of the high field strength extrapolation test is determined based on the third value and the fourth value, including: calculating the difference between the third value and the fourth value to obtain the differential mode voltage; if the differential mode voltage is less than the preset value, the linear relationship is valid, and the electromagnetic radiation effect test process is completed.

[0144] In an embodiment of the present invention, the second preset field strength may be one or more, which is not limited here. For example, if two high field strength extrapolation tests are required, the response size under the two conditions can be recorded by increasing 20 dB each time on the basis of the first preset field strength, observing the response of the right-end through-type load during irradiation excitation and injection excitation after field strength extrapolation as the nonlinear change of the impedance of the right-end EUT changes, and recording the differential mode response of the right-end EUT under the two excitation conditions. This method conducts two field strength extrapolation experiments, each time increasing by 20 dB, and each time changing the impedance of the right-end EUT. It is worth noting that in the extrapolation test, the impedance value of the right-end through-type load is also changed to simulate the nonlinear change of the EUT impedance under strong field conditions.

[0145] In summary, the beneficial effects of the present invention are specifically as follows:

[0146] 1. By considering the influence of the current injection probe access on the equivalent radiation effect test during the experiment, the experimental error caused by the current injection probe access can be effectively reduced, so as to carry out the correction process and complete the equivalent electromagnetic radiation effect test more accurately.

[0147] It should be understood that the order of execution of the steps in the above embodiment does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0148] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention.

Claims

1. A large current injection equivalent electromagnetic radiation effect test calibration method, characterized in that: include: Under a first preset field strength, using a radiation source to irradiate the parallel two-wire cable, and recording a first value of the spectrum analyzer; Maintaining the radiation source irradiation, injecting current into the probe, connecting the probe to the preset load, and then inserting the probe into the cable, and recording the second value of the spectrum analyzer; Calculating an experimental error based on the first value and the second value; Stop irradiation from the radiation source, inject a current into the probe and connect it to the signal source, then adjust the injection power of the signal source to determine a first injection power that is the same as the first value; Determining a linear relationship between a signal source and a radiation source according to the first preset field strength, the test error, and the first injection power; A high field strength extrapolation test is performed based on the linear relationship to complete the electromagnetic radiation effect test process.

2. The large current injection equivalent electromagnetic radiation effect test calibration method according to claim 1 is characterized in that: Determining a linear relationship between a signal source and a radiation source according to the first preset field strength, the test error, and the first injection power includes: Among them, V S0 is the first injection power, Δ is the test error, and E0 is the first preset field strength.

3. The large current injection equivalent electromagnetic radiation effect test calibration method according to claim 1 is characterized in that: Before calculating the test error according to the first value and the second value, the method further includes: Get the frequency of the current injection probe; According to the frequency point of the current injection probe, it is determined whether to execute the step of calculating the test error according to the first value and the second value.

4. The large current injection equivalent electromagnetic radiation effect test calibration method according to claim 3 is characterized in that: Determining whether to perform a step of calculating a test error according to the first value and the second value according to the frequency point of the current injection probe includes: When the frequency point of the current injection probe is greater than the preset frequency point, a step of calculating a test error according to the first value and the second value is performed.

5. The large current injection equivalent electromagnetic radiation effect test calibration method according to claim 3 is characterized in that: Determining whether to perform a step of calculating a test error according to the first value and the second value according to the frequency point of the current injection probe includes: When the frequency point of the current injection probe is not greater than the preset frequency point, the step of calculating the test error according to the first value and the second value is not performed, and the following steps are performed instead: Stop irradiation from the radiation source, inject a current into the probe and connect it to the signal source, then adjust the injection power of the signal source to determine a first injection power that is the same as the first value; Determining a linear relationship between a signal source and a radiation source according to the first preset field strength and the first injection power; A high field strength extrapolation test is performed based on the linear relationship to complete the electromagnetic radiation effect test process.

6. The large current injection equivalent electromagnetic radiation effect test calibration method according to claim 1, characterized in that: According to the linear relationship, a high field strength extrapolation test is performed to complete the electromagnetic radiation effect test process, including: Obtaining a second preset field strength required to be verified in a high field strength extrapolation test; wherein the second preset field strength is greater than the first preset field strength; Under the second preset field strength, use the radiation source to irradiate the parallel two-wire cable, and record the third value of the spectrum analyzer; Calculating a second injection power according to the linear relationship; Stop irradiation from the radiation source, connect the current injection probe to the signal source and then insert the cable, adjust the injection power of the signal source to the second injection power, and record the fourth value of the spectrum analyzer; According to the third value and the fourth value, the differential mode response of the high field strength extrapolation test is determined to complete the electromagnetic radiation effect test process.

7. The large current injection equivalent electromagnetic radiation effect test calibration method according to claim 6, characterized in that: Determining a differential mode response of a high field strength extrapolation test according to the third value and the fourth value includes: Calculate the difference between the third value and the fourth value to obtain a differential mode voltage; If the differential mode voltage is less than the preset value, the linear relationship is valid, and the electromagnetic radiation effect test process is completed.

8. An equivalent electromagnetic radiation effect test system, characterized in that: The large current injection equivalent electromagnetic radiation effect test correction method as described in any one of claims 1 to 7 above is applied to the system, the system comprising: a coaxial load, a parallel two-wire cable, an antenna, a signal source, a current injection probe, a matching load, a through load, a signal conversion module and a receiver; The coaxial load, parallel two-wire cable, antenna, current injection probe, matching load and through-type load are all arranged in a microwave darkroom; The coaxial load is connected to the first end of the parallel two-wire cable; the through-type load is connected to the second end of the parallel two-wire cable; and the signal conversion module is used to connect the through-type load arranged in the microwave darkroom with a receiver outside the microwave darkroom.

9. The equivalent electromagnetic radiation effect test system according to claim 8, characterized in that: When the system irradiates the parallel two-wire cable, the signal source and the antenna in the microwave darkroom form a radiation source, and the signal source outputs power corresponding to the first preset field strength or the second preset field strength to complete the irradiation process; When the system performs current injection on the parallel two-wire cable, the signal source is connected to the current injection probe in the microwave darkroom, and the signal source outputs the first injection power or the second injection power to complete the current injection process.

10. The equivalent electromagnetic radiation effect test system according to claim 9, characterized in that: After the irradiation process is completed, the radiation source keeps running, and the current injection probe is connected to the matching load and then inserted into the cable to complete the error test process.

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