Electromagnetic signal measurement method and device, computer device and storage medium

Abstract

The application relates to an electromagnetic signal measurement method, device, computer equipment and storage medium. The method comprises the following steps: firstly, a near-field probe calibration matrix of an electromagnetic near-field probe calibration system is acquired, the near-field probe calibration matrix being generated based on characteristics of transmission signals in a closed loop of the electromagnetic near-field probe calibration system under different loads; then, an initial electromagnetic signal of a measured electronic device is corrected according to the near-field probe calibration matrix, so that a standard electromagnetic signal of the measured electronic device is obtained; finally, an electromagnetic interference result of the measured electronic device is determined according to the standard electromagnetic signal. The initial electromagnetic signal is obtained by measuring the measured electronic device through an electromagnetic field probe connected with the electromagnetic near-field probe calibration system. The electromagnetic interference of the electronic device can be accurately analyzed by using the method.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of signal processing, and in particular to an electromagnetic signal measurement method and device, computer equipment and a storage medium. BACKGROUND

[0002] With the trend of miniaturization and high frequency of electronic devices, electromagnetic interference (EMI) has gradually become a technical bottleneck for improving the performance of electronic devices. Based on this, the electromagnetic interference problem of the electronic device can be diagnosed and analyzed by measuring the electromagnetic signal on the electronic device.

[0003] In related technologies, a near-field probe is usually connected with a network analyzer to form an electromagnetic near-field probe calibration system, and the electromagnetic signal of the electronic device is measured by the near-field probe. Then, the network analyzer analyzes the electromagnetic interference of the electronic device according to the electromagnetic signal measured by the near-field probe.

[0004] However, the electromagnetic interference of the electronic device cannot be accurately analyzed in the related technologies. SUMMARY

[0005] Therefore, it is necessary to provide an electromagnetic signal measurement method, device, computer equipment and storage medium capable of accurately analyzing the electromagnetic interference of the electronic device to solve the above technical problems.

[0006] In a first aspect, the present application provides an electromagnetic signal measurement method applied to an electromagnetic near-field probe calibration system, and the method comprises:

[0007] Obtaining a near-field probe calibration matrix of the electromagnetic near-field probe calibration system; the near-field probe calibration matrix is generated based on the characteristics of the transmission signal in the closed loop of the electromagnetic near-field probe calibration system under different loads;

[0008] According to the near-field probe calibration matrix, the initial electromagnetic signal of the measured electronic device is corrected to obtain a standard electromagnetic signal of the measured electronic device; the initial electromagnetic signal is obtained by measuring the measured electronic device through an electromagnetic field probe connected with the electromagnetic near-field probe calibration system;

[0009] According to the standard electromagnetic signal, the electromagnetic interference result of the measured electronic device is determined.

[0010] In one embodiment, obtaining the near-field probe calibration matrix of the electromagnetic near-field probe calibration system comprises:

[0011] The scattering coefficient transmission parameters of the multiple calibration pieces are obtained through the multiple calibration pieces connected with the electromagnetic near-field probe calibration system; each calibration piece is a standard piece error source for the electromagnetic near-field probe calibration system, and each calibration piece and the electromagnetic near-field probe calibration system form a closed loop with different loads after being connected;

[0012] The near-field probe calibration matrix is generated according to the scattering coefficient transmission parameters of the multiple calibration pieces.

[0013] In one of the embodiments, the scattering coefficient transmission parameters of the calibration pieces are obtained through the multiple calibration pieces connected with the electromagnetic near-field probe calibration system, including:

[0014] The closed loops corresponding to each calibration piece and the electromagnetic near-field probe calibration system are obtained through the multiple calibration pieces connected with the electromagnetic near-field probe calibration system.

[0015] The multiple transmission parameters of the electromagnetic near-field probe calibration system in the closed loops are obtained according to the transmission characteristics of the closed loops.

[0016] The scattering coefficient transmission parameters of the electromagnetic near-field probe calibration system in the calibration pieces are obtained according to the multiple transmission parameters of the electromagnetic near-field probe calibration system in the closed loops.

[0017] In one of the embodiments, if the calibration piece is a straight-through calibration piece, the closed loop is a first straight-through loop.

[0018] If the calibration piece is a transmission line calibration piece, the closed loop is a second straight-through loop.

[0019] In one of the embodiments, the scattering coefficient transmission parameters of the multiple calibration pieces generate the near-field probe calibration matrix, including:

[0020] The standard impedance parameter matrix between each port of the electromagnetic near-field probe calibration system is obtained.

[0021] The test port parameter matrix between each port of the electromagnetic near-field probe calibration system is obtained according to the scattering coefficient transmission parameters of the multiple calibration pieces.

[0022] The near-field probe calibration matrix is generated according to the standard impedance parameter matrix and the test port parameter matrix.

[0023] In one of the embodiments, the test port parameter matrix between each port of the electromagnetic near-field probe calibration system is obtained according to the scattering coefficient transmission parameters of the multiple calibration pieces, including:

[0024] The error parameter matrix is calculated according to the scattering coefficient transmission parameters.

[0025] The test port parameter matrix between each port of the electromagnetic near-field probe calibration system is obtained according to the error parameter matrix.

[0026] In one embodiment, a near-field probe calibration matrix is generated according to a standard impedance parameter matrix and a test port parameter matrix, comprising:

[0027] fusing the test port parameter matrix into the standard impedance parameter matrix to obtain a fused port parameter matrix;

[0028] performing a number domain conversion on the fused port parameter matrix to obtain the near-field probe calibration matrix.

[0029] In a second aspect, the present application further provides an electromagnetic signal measurement device applied to an electromagnetic near-field probe calibration system. The device comprises:

[0030] a matrix obtaining module configured to obtain a near-field probe calibration matrix of the electromagnetic near-field probe calibration system, wherein the near-field probe calibration matrix is generated based on characteristics of transmission signals in a closed loop of the electromagnetic near-field probe calibration system under different loads;

[0031] a signal obtaining module configured to correct an initial electromagnetic signal of a measured electronic device according to the near-field probe calibration matrix to obtain a standard electromagnetic signal of the measured electronic device, wherein the initial electromagnetic signal is obtained by measuring the measured electronic device through an electromagnetic field probe connected to the electromagnetic near-field probe calibration system;

[0032] a result determining module configured to determine an electromagnetic interference result of the measured electronic device according to the standard electromagnetic signal.

[0033] In a third aspect, the present application further provides a computer device. The computer device comprises a memory and a processor, the memory stores a computer program, and the processor implements the steps of the method in any one of the embodiments of the first aspect when executing the computer program.

[0034] In a fourth aspect, the present application further provides a computer readable storage medium. The computer readable storage medium stores a computer program, and the computer program implements the steps of the method in any one of the embodiments of the first aspect when executed by a processor.

[0035] In a fifth aspect, the present application further provides a computer program product. The computer program product comprises a computer program, and the computer program implements the steps of the method in any one of the embodiments of the first aspect when executed by a processor.

[0036] The electromagnetic signal measurement method, apparatus, computer equipment, and storage medium provided in this application first acquire the near-field probe calibration matrix of an electromagnetic near-field probe calibration system. This near-field probe calibration matrix is ​​generated based on the characteristics of the transmitted signals in closed loops under different loads of the electromagnetic near-field probe calibration system. Then, the initial electromagnetic signal of the electronic device under test is corrected according to the near-field probe calibration matrix to obtain the standard electromagnetic signal of the electronic device under test. Finally, the electromagnetic interference result of the electronic device under test is determined based on the standard electromagnetic signal. The initial electromagnetic signal is obtained by measuring the electronic device under test using an electromagnetic field probe connected to the electromagnetic near-field probe calibration system. Since this method obtains the standard electromagnetic signal based on the initial electromagnetic signal and the near-field probe calibration matrix generated by the electromagnetic near-field probe calibration system in closed loops under different loads, it is equivalent to considering the influence of the measurement components other than the near-field probe in the electromagnetic near-field probe calibration system on the measurement results during the measurement of the electromagnetic signal of the electronic device under test, and quantifying this influencing factor into a near-field probe calibration matrix. This results in a more accurate measurement result of the electromagnetic signal of the electronic device under test. Attached Figure Description

[0037] Figure 1 This is a diagram illustrating the application environment of an electromagnetic signal measurement method in one embodiment.

[0038] Figure 2 This is a flowchart illustrating an electromagnetic signal measurement method in one embodiment;

[0039] Figure 3 This is a flowchart illustrating a method for obtaining a near-field probe calibration matrix in one embodiment;

[0040] Figure 4 This is a flowchart illustrating a method for obtaining scattering coefficient transmission parameters in one embodiment;

[0041] Figure 5 This is a schematic diagram of the through-type calibration component in one embodiment;

[0042] Figure 6 This is a schematic diagram of the structure of the transmission calibration component in one embodiment;

[0043] Figure 7 This is a flowchart illustrating the near-field probe calibration matrix acquisition method in another embodiment;

[0044] Figure 8 This is a schematic diagram of the probe measurement calibration model in one embodiment;

[0045] Figure 9 This is a flowchart illustrating a method for obtaining a test port parameter matrix in one embodiment;

[0046] Figure 10 Fig. 11 is a flowchart of a method for obtaining a near-field probe calibration matrix in another embodiment;

[0047] Figure 11 Fig. 12 is a block diagram of an electromagnetic signal measurement device in an embodiment;

[0048] Figure 12 Fig. 13 is a diagram of an internal structure of a computer device in an embodiment. DETAILED DESCRIPTION

[0049] In order to make the purposes, technical solutions and advantages of the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application.

[0050] The electromagnetic signal measurement method provided by the embodiments of the present application can be applied in an application environment as shown in Fig. 1. Figure 1 The electromagnetic near-field probe calibration system 102 includes a network analyzer 1021 and a near-field probe 1022, and the near-field probe 1022 is provided with a probe. When the probe moves on the surface of the electronic device 104 under test, the network analyzer 1021 obtains the electromagnetic signal of the electronic device 104 under test.

[0051] Generally, the electromagnetic field signal generated on the surface of an electronic device is measured by using a near-field probe, and a microstrip line or a grounded coplanar waveguide (GCPW) as a standard magnetic field source is a very practical ultra-wideband near-field probe calibration method. As a practical tool for electromagnetic interference diagnosis and analysis, the design, characterization and application of the near-field probe have been widely studied in recent years. The main applications of the near-field probe include conducted emission measurement, radiated emission measurement, electromagnetic interference source positioning, signal and noise measurement, IGBT fault positioning, etc. These applications are related to the characteristics of the probe, such as frequency response (FR), calibration factor (CF) and common mode rejection ratio (CMRR).

[0052] The frequency of the electromagnetic field limits the calibration range in most near-field probe calibration methods. The related art proposes a calibration method using a standard electromagnetic field established in a transverse electric and magnetic (TEM) chamber, which can generate a standard electromagnetic field. Since the size of the probe is much smaller than the TEM, the probe has little effect on the electromagnetic field, so it is a relatively accurate probe calibration method. However, the frequency of the magnetic field established by this method is still limited by the frequency of the electromagnetic field, and it cannot calibrate the frequency range up to 20 GHz, and the measurement setup is very complex. On this basis, the related art proposes a gigahertz transverse electromagnetic (GTEM) cell method for calculating the parallel plate method of the 9 kHz to 100 MHz probe and the tapered transmission line method for calculating the 9 kHz to 20 GHz probe to generate an electromagnetic field with a wider frequency range, which facilitates the detection of electromagnetic signals of electronic devices by the near-field probe.

[0053] Although the above method solves the limitation of the ultra-wideband frequency, there are still some calibration problems to be solved. One of the problems is that the calibration curve of the ultra-wideband near-field probe calibration method will be affected by the embedded part that is unnecessary but must be embedded under ideal conditions for measurement.

[0054] The related art proposes a calibration method based on air or dielectric transmission lines (such as microstrip structures or grounded coplanar waveguide structures) as a common method for magnetic field probes. However, this method can introduce other problems, such as CF ripple, attenuation, and phase delay of the calibrator. These problems are not from the probe itself, but from the embedded part of the calibrator. Based on this, the embodiments of the present application propose a new electromagnetic signal measurement method based on the symmetry de-embedding technology of the GCPW calibrator, which quantifies the influence of the embedded part of the calibrator on the measurement results as a calibration matrix, and calculates the initial measurement results according to the calibration matrix to effectively reduce the influence of the embedded part on the calibration curve, including reducing the ripple, compensating for the attenuation and phase delay of the frequency response and the calibration factor.

[0055] In order to accurately analyze the electromagnetic interference of electronic devices, the present application provides an electromagnetic signal measurement method. In the embodiments of the present application, the electromagnetic signal measurement method is used in the electromagnetic near-field probe calibration system 102 in Figure 1 , as shown in Figure 2 , the measurement method includes the following steps:

[0056] S220, obtaining a near-field probe calibration matrix of the electromagnetic near-field probe calibration system; the near-field probe calibration matrix is generated based on the characteristics of the transmission signals in the closed loop of the electromagnetic near-field probe calibration system under different loads.

[0057] The electromagnetic near-field probe calibration system refers to a device for measuring electromagnetic signals of a measuring equipment, and specifically includes a network analyzer and a near-field probe. The network analyzer is a new type of instrument for measuring network parameters, and can directly measure complex scattering parameters of a two-port or single-port network that is active or passive, reversible or irreversible, and give the amplitude, phase and frequency characteristics of each scattering parameter in a sweep frequency mode. In the embodiments of the present application, the network analyzer can be a vector network analyzer for electromagnetic wave energy, which can measure the amplitude of various parameters of a single-port or two-port network, and can also measure the phase.

[0058] The near-field probe calibration matrix represents the gap between the measurement data of the measured electronic equipment obtained by the network analyzer and the actual data of the measured electronic equipment. When the network analyzer measures the measured electronic equipment, some embedded devices such as calibrators and test cables are usually included, which will affect the accuracy of the measurement data of the measured electronic equipment and cause measurement errors. At this time, the measurement results are corrected according to the near-field probe calibration matrix, which can eliminate the measurement errors of the test data caused by the embedded devices.

[0059] It should be noted that the embedded devices are fixed in each measurement process, and the measurement errors caused by the embedded devices in each measurement are also fixed. In each measurement, the measurement results are corrected according to the near-field probe calibration matrix generated by the embedded devices to eliminate the measurement errors caused by the embedded devices. That is, for the same measuring equipment, since the embedded devices are the same, the near-field probe calibration matrix is also the same, that is, the near-field probe calibration matrix has repeatability.

[0060] Specifically, the network analyzer is connected with different calibration pieces to construct electromagnetic near-field probe calibration systems corresponding to different calibration pieces, and then the errors included in the electromagnetic near-field probe calibration systems when connecting the near-field probe are obtained according to the measurement parameters of different electromagnetic near-field probe calibration systems, and the errors are taken as the near-field probe calibration matrix to correct the electromagnetic signals of the measured electronic equipment.

[0061] S240, correcting the initial electromagnetic signal of the measured electronic equipment according to the near-field probe calibration matrix to obtain a standard electromagnetic signal of the measured electronic equipment; the initial electromagnetic signal is obtained by measuring the measured electronic equipment through an electromagnetic field probe connected with the electromagnetic near-field probe calibration system.

[0062] The near-field probe is a device for finding interference sources in cooperation with a spectrum analyzer. According to the type of electromagnetic field, the near-field probe can be divided into an electric field probe and a magnetic field probe. If it is high voltage and weak current, the electric field plays a greater role, and the electric field probe is selected. If it is low voltage and strong current, the magnetic field plays a greater role, and the magnetic field probe is selected. It should be noted that when the near-field probe gradually moves away from the measured electronic device, the decay rate of the magnetic field is faster than that of the electric field, so the near-field probe is mostly selected as the magnetic field probe.

[0063] Specifically, the initial electromagnetic signal is obtained by first moving the near-field probe on the surface of the measured electronic device, and the near-field probe receives the electromagnetic signal of the measured electronic device. Then, since the near-field probe is connected to the port of the network analyzer, the near-field probe transmits the received electromagnetic signal to the network analyzer, and the network analyzer takes the electromagnetic signal of the measured electronic device received by the near-field probe as the initial electromagnetic signal.

[0064] Further, the standard electromagnetic signal is obtained by calculating the initial electromagnetic signal and the near-field probe calibration matrix after obtaining the initial electromagnetic signal of the measured electronic device and the near-field probe calibration matrix, and outputting the standard electromagnetic signal of the measured electronic device.

[0065] Optionally, the near-field probe calibration matrix can be embedded in the network analyzer, and the network analyzer outputs the standard electromagnetic signal of the measured electronic device according to the initial electromagnetic signal of the measured electronic device and the near-field probe calibration matrix.

[0066] Optionally, the initial electromagnetic signal and the near-field probe calibration matrix can be input to a computer device, and the initial electromagnetic signal and the near-field probe calibration matrix are processed according to the preset algorithm of the computer device to obtain the standard electromagnetic signal of the measured electronic device.

[0067] S260, determining the electromagnetic interference result of the measured electronic device according to the standard electromagnetic signal.

[0068] It should be noted that when the near-field probe continuously moves on the surface of the measured electronic device, the standard electromagnetic signal of the measured electronic device is continuous, and the electromagnetic interference of the measured electronic device is determined according to the continuous standard electromagnetic signal. Specifically, if the standard electromagnetic signal of the measured electronic device fluctuates within a preset range, it indicates that the development and use of the measured electronic device are normal. If the electromagnetic signal of the measured electronic device fluctuates greatly, the position of the measured electronic device corresponding to the near-field probe can be preliminarily judged as the fault point of the measured electronic device, and the position with the largest fluctuation amplitude of the standard electromagnetic signal is the position with the most serious electromagnetic signal leakage of the measured electronic device, that is, the interference source of the measured electronic device.

[0069] The electromagnetic signal measurement method provided in the embodiments of the present application first acquires a near-field probe calibration matrix of an electromagnetic near-field probe calibration system, the near-field probe calibration matrix being generated based on characteristics of transmission signals of the electromagnetic near-field probe calibration system in closed loops with different loads; then corrects an initial electromagnetic signal of the electronic device under test according to the near-field probe calibration matrix to obtain a standard electromagnetic signal of the electronic device under test; and finally determines an electromagnetic interference result of the electronic device under test according to the standard electromagnetic signal. The initial electromagnetic signal is obtained by measuring the electronic device under test by an electromagnetic field probe connected with the electromagnetic near-field probe calibration system. Since the method is based on the initial electromagnetic signal and the near-field probe calibration matrix generated by the electromagnetic near-field probe calibration system in the closed loops with different loads, the standard electromagnetic signal is obtained. In other words, in the process of measuring the electromagnetic signal of the electronic device under test, the influence of the measurement part of the electromagnetic near-field probe calibration system except the near-field probe on the measurement result is considered, and the influence factor is quantified as a near-field probe calibration matrix, so that the measurement result of the electromagnetic signal of the electronic device under test is more accurate.

[0070] When acquiring the electromagnetic signal of the electronic device under test, the near-field probe calibration matrix is generally combined with the measured electromagnetic signal to calculate an accurate standard electromagnetic signal. Based on this, the specific acquisition method of the near-field probe calibration matrix is described below through an embodiment.

[0071] In one embodiment, as shown in Figure 3 the process of acquiring the near-field probe calibration matrix of the electromagnetic near-field probe calibration system includes the following steps:

[0072] S320, acquire scattering coefficient transmission parameters of a plurality of calibration pieces connected with the electromagnetic near-field probe calibration system; each calibration piece is a standard piece error source of the electromagnetic near-field probe calibration system, and each calibration piece and the electromagnetic near-field probe calibration system form a closed loop with different loads after being connected.

[0073] The scattering coefficient transmission parameters include return loss, reverse transmission coefficient, insertion loss and reflection coefficient. Specifically, the return loss and insertion loss transmission parameters are acquired according to the transmission loss characteristics of the closed loop, and the reverse transmission coefficient and reflection coefficient are acquired according to the forward and reverse transmission characteristics of the closed loop.

[0074] The electromagnetic near-field probe calibration system is connected with the near-field probe and the embedded device related to the near-field probe when connected with the near-field probe, and the error of the embedded device will affect the final measurement result. In order to accurately quantify the influence of the embedded device on the measurement result, different calibration pieces are used as error sources of the electromagnetic near-field probe calibration system, a closed loop is formed by connecting the network analyzer and the different calibration pieces, and the scattering coefficient transmission parameters of the different calibration pieces are obtained. Since the calibration piece and the network analyzer can be directly connected to form the electromagnetic near-field probe calibration system, or can be connected through the near-field probe and other embedded devices to form the electromagnetic near-field probe calibration system, correspondingly, the scattering coefficient transmission parameters of the multiple calibration pieces obtained contain part of the error of the embedded device and part of the error of the embedded device.

[0075] In S340, the near-field probe calibration matrix is generated according to the scattering coefficient transmission parameters of the multiple calibration pieces.

[0076] The port of the network analyzer connected with the calibration piece is regarded as an actual port, and the port of the network analyzer connected with the calibration piece after removing the error caused by the embedded device is regarded as a virtual port. The near-field probe calibration matrix represents the error conversion relationship between the actual port and the virtual port.

[0077] After obtaining multiple sets of scattering coefficient transmission parameters, the near-field probe calibration matrix needs to be calculated. Specifically, first, according to the calculation of multiple sets of scattering coefficient transmission parameters, the conversion parameters of each set of actual port and virtual port are obtained respectively, and then the matrix expression of each set of actual port and virtual port is obtained by combining the matrix form of each set of actual port and virtual port; then, the matrix expression of the actual port and the virtual port is obtained by substituting the matrix expression of each set of actual port and virtual port into the expression of the actual port; the matrix expression of the actual port and the virtual port is used as the near-field probe calibration matrix.

[0078] In the embodiments of the present application, the scattering coefficient transmission parameters obtained by the multiple calibration pieces are used to calculate the near-field probe calibration matrix, which represents the error of the electromagnetic near-field probe calibration system in multiple dimensions, and improves the effectiveness of the near-field probe calibration matrix.

[0079] When obtaining the scattering coefficient transmission parameters, a closed loop is generally constructed according to multiple different loads to improve the reliability of the scattering coefficient transmission parameters. Based on this, the specific acquisition method of the scattering coefficient transmission parameters of the network analyzer is described below through an embodiment.

[0080] In one embodiment, as shown in Figure 4 the process of obtaining the scattering coefficient transmission parameters of the network analyzer through the multiple calibration pieces connected with the network analyzer includes the following steps:

[0081] S420, acquiring a closed loop of each calibration piece and the electromagnetic near-field probe calibration system through a plurality of calibration pieces connected with the electromagnetic near-field probe calibration system.

[0082] Two ports of the network analyzer are connected with two ends of a calibration piece, and an input voltage and an input current are connected with the ports of the network analyzer, so that a closed loop including a standard piece and a network analyzer is obtained. When the network analyzer is connected with different calibration pieces, different closed loops are correspondingly formed.

[0083] The calibration piece includes a through calibration piece and a transmission line calibration piece. Figures 5-6 The selection criteria of the calibration piece are described as follows. Figure 5 Fig. 2 is a structural schematic diagram of the through calibration piece. Figure 6 Fig. 3 is a structural schematic diagram of the transmission line calibration piece. Figures 5-6 In the above formula, a3 and b3 represent one port of the calibration piece, a4 and b4 represent another port of the calibration piece, two ports of the calibration piece are connected with two ports of the network analyzer at the same time, and a closed loop is formed. In the calculation process of the near-field probe calibration matrix, the requirement for the selection of the calibration piece is that the transmission line is longer than the through line.

[0084] Based on this, the selection criteria of the through calibration piece and the transmission line calibration piece are described as follows.

[0085] (1) The through calibration piece

[0086] When the electrical length of the through standard piece is 0, there is no loss and no reflection, and the transmission coefficient is 1. When the electrical length is not 0, the characteristic impedance of the through standard piece must be the same as that of the delay line standard piece, and the loss does not need to be known. If the through standard piece is used as the reference measurement surface, the specific value of the electrical length of the through standard piece must be known. At the same time, if the group delay is set to 0 at this time, the reference measurement surface is located in the middle of the through standard piece.

[0087] (2) The transmission line / matching load calibration piece

[0088] The characteristic impedance of the transmission line is used as the reference impedance during measurement, and the system impedance is defined as being consistent with the characteristic impedance of the delay line. The insertion phase difference value between the transmission line and the through line of the through calibration piece must be between 20 degrees and 160 degrees (or-20 degrees to-160 degrees). If the phase difference value is close to 0 or 180 degrees, it is easy to cause phase ambiguity due to the characteristics of the tangent function. In addition, the optimal phase difference value is generally 1 / 4 wavelength or 90 degrees.

[0089] The transmission line calibration piece is realized through two 100Ω surface-mounted impedances. In general, it is easier to design a load at low frequency than at high frequency, which is one of the reasons why multiple delay line standard pieces are used to design calibration pieces at high frequency.

[0090] The phase of a transmission line is related to the phase velocity of the signal, the frequency, and the effective dielectric constant. Since a microstrip line does not have a fixed dielectric constant, the effective dielectric constant must be used to account for the mixture of air and PCB material. The frequency ranges of the multiple transmission lines should overlap to ensure that the multiple transmission lines cover the required frequency range.

[0091] When the operating frequency range is greater than 8:1, that is, the frequency span to the starting frequency ratio is greater than 8, one or more transmission lines must be used to cover the entire frequency range. When the operating frequency is too high, the physical size of the 1 / 4 wavelength transmission line is too short to be manufactured, and at this time, a non-0 length straight line is generally selected to increase the physical size of the delay line by using the difference between the two.

[0092] The matched impedance also establishes the reference impedance during measurement, and the reflection coefficients of the matched load at each test port must be the same.

[0093] S440, according to the transmission characteristics of each closed loop, obtaining multiple transmission parameters of the electromagnetic near-field probe calibration system in each closed loop.

[0094] The transmission characteristics include loss, dispersion, attenuation, polarization, and nonlinear effects, and the corresponding transmission parameters include impedance loss, frequency attenuation, etc. In the closed loop, the network analyzer port obtains four transmission parameters: return loss, insertion loss, reverse transmission coefficient, and reflection coefficient according to the transmission loss characteristics.

[0095] S460, according to the multiple transmission parameters of the electromagnetic near-field probe calibration system in each closed loop, obtaining the scattering coefficient transmission parameters of the electromagnetic near-field probe calibration system in each calibration piece.

[0096] One closed loop corresponds to one calibration piece and a set of transmission parameters, and a set of transmission parameters includes four transmission parameters: return loss, reverse transmission coefficient, insertion loss, and reflection coefficient. Then, for multiple closed loops, multiple sets of scattering coefficient transmission parameters are obtained. For example, if the network analyzer and two standard pieces form closed loop 1 and closed loop 2, respectively, then in each closed loop, four transmission parameters will be generated: return loss, reverse transmission coefficient, insertion loss, and reflection coefficient. These four transmission parameters form a set of scattering coefficient transmission parameters. Since there are two closed loops, a total of eight transmission parameters are generated, and two sets of scattering coefficient transmission parameters are generated.

[0097] In the embodiment of the present application, the manufacturing cost of the calibration piece is low, and the scattering coefficient transmission parameters are obtained by using multiple calibration pieces and network analyzers to form a loop, which can control the measurement cost while ensuring the accuracy of the scattering coefficient transmission parameters.

[0098] In one embodiment, if the calibration piece is a through calibration piece, the closed loop is a first through loop;

[0099] If the calibration piece is a transmission line calibration piece, the closed loop is a second through loop.

[0100] The first through loop corresponding to the through calibration piece is obtained by connecting the through calibration piece with the network analyzer; and then the return loss, reverse transmission coefficient, insertion loss and reflection coefficient of the first through calibration piece are obtained according to the transmission characteristics of the first through loop.

[0101] The second through loop corresponding to the transmission line calibration piece is obtained by connecting the transmission line calibration piece with the network analyzer; and then the return loss, reverse transmission coefficient, insertion loss and reflection coefficient of the first transmission line calibration piece are obtained according to the transmission characteristics of the first transmission line loop.

[0102] In obtaining the electromagnetic signal of the electronic device under test, the calibration piece error data of the network analyzer is generally used for calculation to obtain more accurate system error data. Based on this, the specific obtaining method of the near-field probe calibration matrix is described below through an embodiment.

[0103] In one embodiment, as shown in Figure 7 the process of generating the near-field probe calibration matrix according to the scattering coefficient transmission parameters of the multiple calibration pieces includes the following steps:

[0104] S720, obtaining a standard impedance parameter matrix between each port of the electromagnetic near-field probe calibration system.

[0105] The standard impedance parameter matrix refers to the known impedance between each port of the network analyzer. If the network analyzer has three actual ports in the measurement process, which are port 2, port 3 and port 4. Then, the standard impedance parameter matrix is represented as:

[0106]

[0107] In formula 1, U i represents the input voltage of port i, I i represents the input current of port i, and Z ij represents the impedance from port i to port j.

[0108] S740, obtaining a test port parameter matrix between each port of the electromagnetic near-field probe calibration system according to the scattering coefficient transmission parameters of the multiple calibration pieces.

[0109] The port of the network analyzer connected with the calibration piece is taken as an actual port, the port of the network analyzer connected with the calibration piece after removing the error of the near-field probe is taken as a virtual port, and the near-field probe calibration matrix represents the error conversion relationship between the actual port and the virtual port.

[0110] The connection mode of the standard part and the network analyzer is characterized in the form of an error box. The structure of a probe measurement calibration model is shown in Figure 8 The port 2, the port 3 and the port 4 are actual ports, the port 2 is connected with a near-field probe, the port 3 and the port 4 are connected with two ports of a calibration part, and the port 5 and the port 6 are virtual ports. According to the scattering coefficient transmission matrix of the actual ports, a test port parameter matrix of the actual port 3 and the virtual port 5 is obtained, and a test port parameter matrix of the actual port 4 and the virtual port 6 is obtained. The test port parameter matrix is expressed in the form of a scattering coefficient transmission parameter.

[0111] S760, generating a near-field probe calibration matrix according to the standard impedance parameter matrix and the test port parameter matrix.

[0112] Specifically, first, the test port parameter matrix and the standard impedance parameter matrix are calculated to obtain an initial near-field probe calibration matrix characterized in the form of a scattering coefficient transmission parameter, and then the initial near-field probe calibration matrix is converted in different forms according to the actual measurement requirements of the electronic equipment under test to generate the near-field probe calibration matrix.

[0113] According to the scattering coefficient transmission parameter, the error box is constructed, and the near-field probe calibration matrix is calculated in combination with the standard impedance parameter matrix of each port of the network analyzer, so that the operation is simple, the logic is strong, and the calculation efficiency of the near-field probe calibration matrix can be improved.

[0114] When the near-field probe calibration matrix is obtained, the scattering coefficient transmission parameter of the network analyzer can be used for calculation. Based on this, the specific acquisition method of the test port parameter matrix between each port of the network analyzer is described below through an embodiment.

[0115] In an embodiment, as shown in Figure 9 According to the scattering coefficient transmission parameter of the multiple calibration parts, the process of obtaining the test port parameter matrix between each port of the electromagnetic near-field probe calibration system includes the following steps:

[0116] S920, calculating an error parameter matrix according to the scattering coefficient transmission parameter.

[0117] The scattering coefficient transmission parameter corresponds to the actual port of the network analyzer, and the error parameter matrix corresponds to the virtual port of the network analyzer after removing the system error.

[0118] Exemplarily, if in the probe measurement calibration model, the through calibration piece and the network analyzer are connected in the through closed loop, the scattering coefficient transmission parameter corresponding to the actual port of the network analyzer is T=[T11 T12;T21 T22]; if the transmission line calibration piece and the network analyzer are connected in the transmission line loop, the scattering coefficient transmission parameter corresponding to the actual port of the network analyzer is L=[L11 L12;L21 L22]. Then the related parameters of the error box are calculated as follows:

[0119]

[0120] E 11 11 22 12 Equation 3

[0121]

[0122] E 12 21 Equation 5

[0123] In Equation 2, e -γl represents the propagation factor, which is expressed as:

[0124]

[0125] According to the related parameters of the error box, the error parameter matrix is calculated as follows:

[0126]

[0127]

[0128]

[0129]

[0130] Wherein, Z0 is the impedance parameter inside the network analyzer.

[0131] S940, according to the error parameter matrix, the test port parameter matrix between each port of the electromagnetic near-field probe calibration system is obtained.

[0132] After obtaining the error parameter matrix, the test port parameter matrix between each port of the network analyzer can be obtained according to the connection mode of the error box.

[0133] Exemplarily, in the probe measurement calibration model shown in Figure 8 , the test port parameter matrix between the actual port 3 and the virtual port 5, and the test port parameter matrix between the actual port 4 and the virtual port 6 are calculated as follows: ​​​​

[0134]

[0135]

[0136] In the embodiments of the present application, the transmission parameters of each port of the network analyzer are characterized by the error parameter matrix, the principle is simple, the logic is clear, and the test port parameters of each port of the network analyzer can be quickly obtained.

[0137] When the near-field probe calibration matrix is obtained, the initial electromagnetic signal of the measured electronic device can be corrected to calculate the effective standard electromagnetic signal. Based on this, the specific acquisition method of the near-field probe calibration matrix is described below through an embodiment.

[0138] In one embodiment, as shown in Figure 10 The process of generating the near-field probe calibration matrix according to the standard impedance parameter matrix and the test port parameter matrix includes the following steps:

[0139] S1020, the test port parameter matrix is fused into the standard impedance parameter matrix to obtain a fused port parameter matrix.

[0140] Specifically, the test port parameter matrix is substituted into the standard impedance parameter matrix to obtain the fused port parameter matrix. It should be noted that the fused port parameter matrix is expressed in the form of impedance at this time.

[0141] For example, in the probe measurement calibration model shown in Figure 8 The relationship matrix of the probe port 2, the virtual port 5 and the virtual port 6 is expressed as:

[0142]

[0143] The fused port parameter matrix is:

[0144]

[0145] S1040, the fused port parameter matrix is subjected to a number domain conversion process to obtain a near-field probe calibration matrix.

[0146] After obtaining the fused port parameter matrix, since the electromagnetic signal of the measured electronic device is characterized in the form of frequency, such as common-mode rejection ratio, calibration factor, etc., it is necessary to convert the impedance expression form of the fused port parameter matrix into a scattering parameter expression form, so as to be used for the calculation of the electromagnetic signal of the measured electronic device. At this time, the expression of the near-field probe calibration matrix is:

[0147]

[0148] The relationship of the probe port 2, the virtual port 5 and the virtual port 6 is updated as:

[0149]

[0150] Optionally, the magnetic field simultaneously exists the common mode response and the differential mode response, and then the common mode rejection ratio of the measured electronic device is obtained:

[0151]

[0152] FR in formula 17 d is the differential mode frequency response:

[0153]

[0154] FR in formula 17 c is the common mode frequency response:

[0155]

[0156] In the embodiment of the application, since the fusion port parameter matrix is characterized in the form of impedance parameters, the calculation is facilitated, the conversion flexibility of the parameter form is high, and the standard electromagnetic signal of the measured electronic device is easily obtained.

[0157] In one embodiment, an electromagnetic signal measurement method is provided, and the embodiment includes:

[0158] (1) obtaining the transmission parameters of the multiple calibration pieces by connecting the multiple calibration pieces to the electromagnetic near-field probe calibration system.

[0159] (2) obtaining the scattering coefficient transmission parameters of the first through circuit by connecting the network analyzer to the reflection calibration piece.

[0160] (3) obtaining the scattering coefficient transmission parameters of the second through circuit by connecting the network analyzer to the transmission line calibration piece.

[0161] (4) calculating the error parameter matrix according to the scattering coefficient transmission parameters of each closed circuit.

[0162] (5) obtaining the test port parameter matrix between the ports of the network analyzer according to the error parameter matrix.

[0163] (6) obtaining the standard impedance parameter matrix between the ports of the network analyzer.

[0164] (7) fusing the test port parameter matrix into the standard impedance parameter matrix to obtain the fusion port parameter matrix.

[0165] (8) performing the number domain conversion processing on the fusion port parameter matrix to obtain the near-field probe calibration matrix.

[0166] (9) Calibrating the initial electromagnetic signal of the electronic device under test according to the near-field probe calibration matrix to obtain a standard electromagnetic signal of the electronic device under test.

[0167] (10) Determining the electromagnetic interference result of the electronic device under test according to the standard electromagnetic signal.

[0168] In the embodiments of the present application, first, a near-field probe calibration matrix of an electromagnetic near-field probe calibration system is obtained, the near-field probe calibration matrix being generated based on characteristics of transmission signals in a closed loop of the electromagnetic near-field probe calibration system under different loads; then, the initial electromagnetic signal of the electronic device under test is corrected according to the near-field probe calibration matrix to obtain a standard electromagnetic signal of the electronic device under test; finally, the electromagnetic interference result of the electronic device under test is determined according to the standard electromagnetic signal. The initial electromagnetic signal is obtained by measuring the electronic device under test by an electromagnetic field probe connected to the electromagnetic near-field probe calibration system. Since the method is based on the initial electromagnetic signal and the near-field probe calibration matrix generated by the electromagnetic near-field probe calibration system in the closed loop under different loads, the standard electromagnetic signal is obtained. It is equivalent to considering the influence of the measurement part of the electromagnetic near-field probe calibration system except the near-field probe on the measurement result in the process of measuring the electromagnetic signal of the electronic device under test, and quantifying the influence factor as a near-field probe calibration matrix, so that the measurement result of the electromagnetic signal of the electronic device under test is more accurate.

[0169] It should be understood that, although each step in the flowchart involved in the above embodiments is displayed in sequence according to the arrow, these steps are not necessarily executed in the order indicated by the arrow. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other orders. Moreover, at least part of the steps in the flowchart involved in the above embodiments can include multiple steps or stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least part of other steps or steps or stages in other steps.

[0170] Based on the same inventive concept, the embodiments of the present application also provide an electromagnetic signal measurement device for implementing the above-mentioned electromagnetic signal measurement method. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme described in the above method, so the specific limitations in one or more electromagnetic signal measurement device embodiments provided below can refer to the limitations of the electromagnetic signal measurement method in the above text, which will not be repeated here.

[0171] In one embodiment, as Figure 11As shown, an electromagnetic signal measurement device 110 is provided, applied to a network analyzer, comprising a matrix obtaining module 1120, a signal obtaining module 1140 and a result determining module 1160, wherein:

[0172] The matrix obtaining module 1120 is configured to obtain a near-field probe calibration matrix of the electromagnetic near-field probe calibration system; the near-field probe calibration matrix is generated based on characteristics of transmission signals of the electromagnetic near-field probe calibration system in different closed loops.

[0173] The signal obtaining module 1140 is configured to correct an initial electromagnetic signal of the electronic device under test according to the near-field probe calibration matrix to obtain a standard electromagnetic signal of the electronic device under test; the initial electromagnetic signal is obtained by measuring the electronic device under test by an electromagnetic field probe connected with the electromagnetic near-field probe calibration system.

[0174] The result determining module 1160 is configured to determine an electromagnetic interference result of the electronic device under test according to the standard electromagnetic signal.

[0175] In one embodiment, the matrix obtaining module 1120 comprises:

[0176] A first obtaining unit is configured to obtain scattering coefficient transmission parameters of a plurality of calibration pieces connected with the electromagnetic near-field probe calibration system; each calibration piece is a standard piece error source of the electromagnetic near-field probe calibration system, and each calibration piece and the electromagnetic near-field probe calibration system form a closed loop with different loads after being connected;

[0177] A second obtaining unit is configured to generate the near-field probe calibration matrix according to the scattering coefficient transmission parameters of the plurality of calibration pieces.

[0178] In one embodiment, the first obtaining unit comprises:

[0179] A first obtaining sub-unit is configured to obtain a closed loop corresponding to each calibration piece and the electromagnetic near-field probe calibration system by connecting the plurality of calibration pieces with the electromagnetic near-field probe calibration system;

[0180] A second obtaining sub-unit is configured to obtain a plurality of transmission parameters of the electromagnetic near-field probe calibration system in each closed loop according to transmission characteristics of each closed loop;

[0181] A third obtaining sub-unit is configured to obtain scattering coefficient transmission parameters of the electromagnetic near-field probe calibration system in each calibration piece according to the plurality of transmission parameters of the electromagnetic near-field probe calibration system in each closed loop.

[0182] In one embodiment, if the calibration piece is a straight-through calibration piece, the closed loop is a first straight-through loop.

[0183] If the calibration object is a transmission line calibration object, the closed loop is a second through loop.

[0184] In one embodiment, the second obtaining unit comprises:

[0185] The fourth obtaining sub-unit is configured to obtain a standard impedance parameter matrix between ports of the electromagnetic near-field probe calibration system.

[0186] The fifth obtaining sub-unit is configured to obtain a test port parameter matrix between the ports of the electromagnetic near-field probe calibration system according to the scattering coefficient transmission parameters of the plurality of calibration objects.

[0187] The sixth obtaining sub-unit is configured to generate the near-field probe calibration matrix according to the standard impedance parameter matrix and the test port parameter matrix.

[0188] In one embodiment, the fifth obtaining sub-unit is further configured to calculate an error parameter matrix according to the scattering coefficient transmission parameters, and obtain the test port parameter matrix between the ports of the electromagnetic near-field probe calibration system according to the error parameter matrix.

[0189] In one embodiment, the sixth obtaining sub-unit is further configured to fuse the test port parameter matrix into the standard impedance parameter matrix to obtain a fused port parameter matrix, and perform a numerical domain conversion on the fused port parameter matrix to obtain the near-field probe calibration matrix.

[0190] The above-mentioned modules in the electromagnetic signal measurement device can be realized by software, hardware, or a combination thereof. The above-mentioned modules can be embedded in or independent of a processor in a computer device in hardware form, or stored in a memory in a computer device in software form, so as to be called and executed by a processor to perform operations corresponding to the above-mentioned modules.

[0191] In one embodiment, a computer device is provided, which can be a terminal, and an internal structure diagram of the computer device can be as shown in Figure 12The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. The processor, the memory and the input / output interface are connected through a system bus. The communication interface, the display unit and the input device are connected to the system bus through the input / output interface. The processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for running the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is configured to exchange information between the processor and external devices. The communication interface of the computer device is configured to perform wired or wireless communication with external terminals. The wireless communication can be achieved through WIFI, mobile cellular network, NFC (Near Field Communication) or other technologies. The computer program is executed by the processor to implement an electromagnetic signal measurement method. The display unit of the computer device is configured to form a visually visible picture, which can be a display screen, a projection device or a virtual reality imaging device. The display screen can be a liquid crystal display screen or an electronic ink display screen. The input device of the computer device can be a touch layer overlaid on the display screen, or a key, trackball or touchpad arranged on the shell of the computer device, or an external keyboard, touchpad or mouse, etc.

[0192] Those skilled in the art can understand that, Figure 12 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. A specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0193] In one embodiment, a computer device is provided, including a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the following steps:

[0194] Obtaining a near-field probe calibration matrix of the electromagnetic near-field probe calibration system; the near-field probe calibration matrix is generated based on characteristics of transmission signals in a closed loop of the electromagnetic near-field probe calibration system under different loads;

[0195] According to the near-field probe calibration matrix, correcting an initial electromagnetic signal of the electronic device under test to obtain a standard electromagnetic signal of the electronic device under test; the initial electromagnetic signal is obtained by measuring the electronic device under test through an electromagnetic field probe connected to the electromagnetic near-field probe calibration system;

[0196] Determining an electromagnetic interference result of the electronic device under test according to the standard electromagnetic signal.

[0197] In one embodiment, the processor, when executing the computer program, also implements the following steps:

[0198] The scattering coefficient transmission parameters of the plurality of calibration pieces are obtained by connecting the plurality of calibration pieces to the electromagnetic near-field probe calibration system;

[0199] The near-field probe calibration matrix is generated according to the scattering coefficient transmission parameters of the plurality of calibration pieces.

[0200] In one embodiment, the processor, when executing the computer program, also implements the following steps:

[0201] The scattering coefficient transmission parameters of the plurality of calibration pieces are obtained by connecting the plurality of calibration pieces to the electromagnetic near-field probe calibration system;

[0202] The scattering coefficient transmission parameters of the plurality of calibration pieces are obtained by connecting the plurality of calibration pieces to the electromagnetic near-field probe calibration system;

[0203] The scattering coefficient transmission parameters of the plurality of calibration pieces are obtained by connecting the plurality of calibration pieces to the electromagnetic near-field probe calibration system;

[0204] In one embodiment, if the calibration piece is a straight-through calibration piece, the closed loop is a first straight-through loop;

[0205] If the calibration piece is a transmission line calibration piece, the closed loop is a second straight-through loop.

[0206] In one embodiment, the processor, when executing the computer program, also implements the following steps:

[0207] The standard impedance parameter matrix between the ports of the electromagnetic near-field probe calibration system is obtained;

[0208] The test port parameter matrix between the ports of the electromagnetic near-field probe calibration system is obtained according to the scattering coefficient transmission parameters of the plurality of calibration pieces;

[0209] The near-field probe calibration matrix is generated according to the standard impedance parameter matrix and the test port parameter matrix.

[0210] In one embodiment, the processor, when executing the computer program, also implements the following steps:

[0211] The error parameter matrix is calculated according to the scattering coefficient transmission parameters;

[0212] The test port parameter matrix between the ports of the electromagnetic near-field probe calibration system is obtained according to the error parameter matrix.

[0213] In one embodiment, the processor, when executing the computer program, also implements the following steps:

[0214] fuse the test port parameter matrix into the standard impedance parameter matrix to obtain a fused port parameter matrix;

[0215] perform a number field conversion on the fused port parameter matrix to obtain a near-field probe calibration matrix.

[0216] In one embodiment, a computer readable storage medium is provided, which stores a computer program, and the computer program, when executed by a processor, implements the following steps:

[0217] obtain a near-field probe calibration matrix of an electromagnetic near-field probe calibration system; the near-field probe calibration matrix is generated based on characteristics of transmission signals of the electromagnetic near-field probe calibration system in different closed loops with different loads;

[0218] correct an initial electromagnetic signal of the electronic device under test according to the near-field probe calibration matrix to obtain a standard electromagnetic signal of the electronic device under test; the initial electromagnetic signal is obtained by measuring the electronic device under test by an electromagnetic field probe connected to the electromagnetic near-field probe calibration system;

[0219] determine an electromagnetic interference result of the electronic device under test according to the standard electromagnetic signal.

[0220] In one embodiment, the processor, when executing the computer program, also implements the following steps:

[0221] obtain scattering coefficient transmission parameters of a plurality of calibration pieces connected to the electromagnetic near-field probe calibration system; each calibration piece is a standard piece error source of the electromagnetic near-field probe calibration system, and each calibration piece, when connected to the electromagnetic near-field probe calibration system, forms a closed loop with different loads;

[0222] generate the near-field probe calibration matrix according to the scattering coefficient transmission parameters of the plurality of calibration pieces.

[0223] In one embodiment, the processor, when executing the computer program, also implements the following steps:

[0224] obtain a plurality of closed loops corresponding to each calibration piece and the electromagnetic near-field probe calibration system by connecting a plurality of calibration pieces to the electromagnetic near-field probe calibration system;

[0225] obtain a plurality of transmission parameters of the electromagnetic near-field probe calibration system in each closed loop according to transmission characteristics of each closed loop;

[0226] obtain scattering coefficient transmission parameters of the electromagnetic near-field probe calibration system in each calibration piece according to the plurality of transmission parameters of the electromagnetic near-field probe calibration system in each closed loop.

[0227] In one embodiment, if the calibration object is a through calibration object, the closed loop is a first through loop;

[0228] If the calibration object is a transmission line calibration object, the closed loop is a second through loop.

[0229] In one embodiment, the processor, when executing the computer program, further implements the following steps:

[0230] Obtaining a standard impedance parameter matrix between each port of the electromagnetic near-field probe calibration system;

[0231] According to the scattering coefficient transmission parameters of the plurality of calibration objects, obtaining a test port parameter matrix between each port of the electromagnetic near-field probe calibration system;

[0232] According to the standard impedance parameter matrix and the test port parameter matrix, generating a near-field probe calibration matrix.

[0233] In one embodiment, the processor, when executing the computer program, further implements the following steps:

[0234] According to the scattering coefficient transmission parameters, calculating an error parameter matrix;

[0235] According to the error parameter matrix, obtaining a test port parameter matrix between each port of the electromagnetic near-field probe calibration system.

[0236] In one embodiment, the processor, when executing the computer program, further implements the following steps:

[0237] Fusing the test port parameter matrix into the standard impedance parameter matrix to obtain a fused port parameter matrix;

[0238] Performing a number domain conversion on the fused port parameter matrix to obtain a near-field probe calibration matrix.

[0239] In one embodiment, a computer program product is provided, comprising a computer program which, when executed by a processor, implements the following steps:

[0240] Obtaining a near-field probe calibration matrix of the electromagnetic near-field probe calibration system; the near-field probe calibration matrix is generated based on characteristics of transmission signals in different load closed loops of the electromagnetic near-field probe calibration system;

[0241] According to the near-field probe calibration matrix, correcting an initial electromagnetic signal of the electronic device under test to obtain a standard electromagnetic signal of the electronic device under test; the initial electromagnetic signal is obtained by measuring the electronic device under test by an electromagnetic field probe connected to the electromagnetic near-field probe calibration system;

[0242] According to the standard electromagnetic signal, determining an electromagnetic interference result of the electronic device under test.

[0243] In one embodiment, the processor, when executing the computer program, also implements the following steps:

[0244] Obtain the scattering coefficient transmission parameters of the plurality of calibration pieces by connecting the plurality of calibration pieces to the electromagnetic near-field probe calibration system; each calibration piece is a standard piece error source for the electromagnetic near-field probe calibration system, and each calibration piece forms a closed loop with different loads after being connected to the electromagnetic near-field probe calibration system;

[0245] Generate a near-field probe calibration matrix according to the scattering coefficient transmission parameters of the plurality of calibration pieces.

[0246] In one embodiment, the processor, when executing the computer program, also implements the following steps:

[0247] Obtain the closed loops corresponding to each calibration piece and the electromagnetic near-field probe calibration system by connecting the plurality of calibration pieces to the electromagnetic near-field probe calibration system;

[0248] Obtain a plurality of transmission parameters of the electromagnetic near-field probe calibration system in each closed loop according to the transmission characteristics of each closed loop;

[0249] Obtain the scattering coefficient transmission parameters of the electromagnetic near-field probe calibration system in each calibration piece according to the plurality of transmission parameters of the electromagnetic near-field probe calibration system in each closed loop.

[0250] In one embodiment, if the calibration piece is a straight-through calibration piece, the closed loop is a first straight-through loop;

[0251] If the calibration piece is a transmission line calibration piece, the closed loop is a second straight-through loop.

[0252] In one embodiment, the processor, when executing the computer program, also implements the following steps:

[0253] Obtain a standard impedance parameter matrix between each port of the electromagnetic near-field probe calibration system;

[0254] Obtain a test port parameter matrix between each port of the electromagnetic near-field probe calibration system according to the scattering coefficient transmission parameters of the plurality of calibration pieces;

[0255] Generate a near-field probe calibration matrix according to the standard impedance parameter matrix and the test port parameter matrix.

[0256] In one embodiment, the processor, when executing the computer program, also implements the following steps:

[0257] Calculate an error parameter matrix according to the scattering coefficient transmission parameters;

[0258] Obtain a test port parameter matrix between each port of the electromagnetic near-field probe calibration system according to the error parameter matrix.

[0259] In one embodiment, the processor, when executing the computer program, also implements the following steps:

[0260] The test port parameter matrix is fused into the standard impedance parameter matrix to obtain a fused port parameter matrix.

[0261] The fused port parameter matrix is subjected to a number domain conversion process to obtain a near-field probe calibration matrix.

[0262] A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiments can be completed by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer readable storage medium. When the computer program is executed, it can include the processes of the above-mentioned embodiments. Any reference to a memory, a database or other medium in the embodiments provided in the present application can include at least one of a non-volatile memory and a volatile memory. The non-volatile memory can include a read-only memory (ROM), a magnetic tape, a floppy disk, a flash memory, an optical storage, a high-density embedded non-volatile memory, a resistive memory (ReRAM), a magnetoresistive random access memory (MRAM), a ferroelectric random access memory (FRAM), a phase change memory (PCM), a graphene memory, etc. The volatile memory can include a random access memory (RAM) or an external cache memory, etc. As an illustration but not limitation, the RAM can be in various forms, such as a static random access memory (SRAM) or a dynamic random access memory (DRAM), etc. The database involved in the embodiments provided in the present application can include at least one of a relational database and a non-relational database. The non-relational database can include a distributed database based on a block chain, etc., without being limited thereto. The processor involved in the embodiments provided in the present application can be a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., without being limited thereto.

[0263] Any combination of the technical features of the above embodiments can be made. In order to make the description concise, all possible combinations of the technical features in the above embodiments are not described, however, as long as the combination of the technical features does not exist, it should be considered as the scope of the present application.

[0264] The above embodiments only express several implementation ways of the present application, and the description is more specific and detailed, but it should not be understood as a limitation to the patent scope of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, several modifications and improvements can be made, which 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.

Claims

1. A method of measuring an electromagnetic signal, characterized by, The method is applied to an electromagnetic near-field probe calibration system, and comprises the following steps: Obtaining scattering coefficient transmission parameters of each calibration piece based on a closed loop of the electromagnetic near-field probe calibration system under different loads, wherein the closed loop under different loads comprises a first through loop formed by connecting a through calibration piece and a second through loop formed by connecting a transmission line calibration piece; Determining error box related parameters according to the scattering coefficient transmission parameters of the first through loop and the scattering coefficient transmission parameters of the second through loop, wherein the error box related parameters comprise: wherein T11, T12, T21 and T22 are scattering coefficient transmission parameters of the first through circuit, and L11, L12, L21 and L22 are scattering coefficient transmission parameters of the second through circuit; For the propagation factor, the corresponding expression is: Calculating an error parameter matrix according to the error box related parameters and impedance parameters of a network analyzer; Obtaining a test port parameter matrix between each port of the electromagnetic near-field probe calibration system according to the error parameter matrix; Generating a near-field probe calibration matrix according to standard impedance parameter matrices between each port of the electromagnetic near-field probe calibration system and the test port parameter matrix, wherein the near-field probe calibration matrix represents measurement errors generated by embedding equipment in a process of measuring an electronic device by the network analyzer; Correcting an initial electromagnetic signal of the measured electronic device according to the near-field probe calibration matrix to obtain a standard electromagnetic signal of the measured electronic device, wherein the initial electromagnetic signal is obtained by measuring the measured electronic device by an electromagnetic field probe connected to the electromagnetic near-field probe calibration system; Determining that the measured electronic device is in a normal working state in a case that the standard electromagnetic signal of the measured electronic device fluctuates within a preset range; Preliminarily judging that a corresponding spatial position of the measured electronic device is a fault point and determining a position with the largest fluctuation amplitude of the standard electromagnetic signal as an interference source of the measured electronic device in a case that the standard electromagnetic signal of the measured electronic device fluctuates beyond the preset range.

2. The method of claim 1, wherein, Each calibration piece is a standard piece error generation source of the electromagnetic near-field probe calibration system, and each calibration piece forms the closed loop under different loads after being connected to the electromagnetic near-field probe calibration system; Generating the near-field probe calibration matrix according to scattering coefficient transmission parameters of a plurality of calibration pieces.

3. The method of claim 2, wherein, Before the step of obtaining the scattering coefficient transmission parameters of each calibration piece based on the closed loop of the electromagnetic near-field probe calibration system under different loads, the method further comprises the following steps: Obtaining a corresponding closed loop of each calibration piece and the electromagnetic near-field probe calibration system by connecting a plurality of calibration pieces to the electromagnetic near-field probe calibration system.

4. The method of claim 2, wherein, The step of obtaining the scattering coefficient transmission parameters of each calibration piece comprises the following steps: Obtaining a plurality of transmission parameters of the electromagnetic near-field probe calibration system in each closed loop according to transmission characteristics of each closed loop; Obtaining scattering coefficient transmission parameters of the electromagnetic near-field probe calibration system in each calibration piece according to the plurality of transmission parameters of the electromagnetic near-field probe calibration system in each closed loop.

5. The method according to any one of claims 1 to 4, characterized in that, The expression of the error parameter matrix is ; The corresponding calculation expression of the step of calculating the error parameter matrix according to the error box related parameters and the impedance parameters of the network analyzer is as follows: Wherein, Z0 is the impedance parameter of the network analyzer.

6. The method of claim 5, wherein, The near-field probe calibration matrix is generated according to the standard impedance parameter matrix between each port of the electromagnetic near-field probe calibration system and the test port parameter matrix, and the near-field probe calibration matrix comprises: The test port parameter matrix is fused into the standard impedance parameter matrix to obtain a fused port parameter matrix; The fused port parameter matrix is subjected to a numerical domain conversion process to obtain the near-field probe calibration matrix.

7. An electromagnetic signal measuring device, characterized by The device is applied to an electromagnetic near-field probe calibration system, and the device comprises: A matrix acquisition module is configured to acquire scattering coefficient transmission parameters of each calibration piece based on closed loops of different loads of the electromagnetic near-field probe calibration system, wherein the closed loops of different loads comprise a first through loop connected with a through calibration piece and a second through loop connected with a transmission line calibration piece. Error box related parameters are determined according to the scattering coefficient transmission parameters of the first through loop and the scattering coefficient transmission parameters of the second through loop, wherein the error box related parameters comprise: where T11, T12, T21 and T22 are the scattering coefficient transmission parameters of the first through circuit, and L11, L12, L21 and L22 are the scattering coefficient transmission parameters of the second through circuit; For the propagation factor, the corresponding expression is: An error parameter matrix is calculated according to the error box related parameters and impedance parameters of a network analyzer, a test port parameter matrix between each port of the electromagnetic near-field probe calibration system is acquired according to the error parameter matrix, and a near-field probe calibration matrix is generated according to a standard impedance parameter matrix between each port of the electromagnetic near-field probe calibration system and the test port parameter matrix, wherein the near-field probe calibration matrix represents measurement errors generated by equipment embedded in a process of measuring an electronic device by the network analyzer. A signal acquisition module is configured to correct an initial electromagnetic signal of a measured electronic device according to the near-field probe calibration matrix to obtain a standard electromagnetic signal of the measured electronic device, wherein the initial electromagnetic signal is obtained by measuring the measured electronic device by an electromagnetic field probe connected with the electromagnetic near-field probe calibration system. A result determination module is configured to determine that a working state of the measured electronic device is normal in a case where the standard electromagnetic signal of the measured electronic device fluctuates within a preset range, preliminarily determine that a corresponding spatial position of the measured electronic device is a fault point in a case where the standard electromagnetic signal of the measured electronic device fluctuates beyond the preset range, and determine a position with a maximum fluctuation amplitude of the standard electromagnetic signal as an interference source of the measured electronic device.

8. The apparatus of claim 7, wherein, The matrix acquisition module is further configured to fuse the test port parameter matrix into the standard impedance parameter matrix to obtain a fused port parameter matrix, and to perform a numerical domain conversion process on the fused port parameter matrix to obtain the near-field probe calibration matrix. 9.A computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the computer device is configured to perform the method according to any one of claims 1-8 when the computer program is executed by the processor. The processor executes the computer program to implement the steps of the method of any one of claims 1 to 6.

10. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the method of any one of claims 1 to 6.

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