S-parameter test method for suppressing ripple, electronic device, and storage medium

Abstract

The application provides a kind of S parameter test method for inhibiting ripple, electronic equipment and storage medium, comprising: based on preset scanning power and preset scanning point number, control vector network analyzer to be measured in the test frequency range of measured piece to be measured piece calibration and frequency sweep test, determine the S parameter of measured piece;In the case where the S parameter exists ripple, reduce the test frequency range;The test frequency range after reduction is used as the test frequency range of new measured piece, repeat the above steps;Until it is determined that there is no ripple S parameter as the target S parameter of measured piece after inhibiting ripple.The application inhibits the ripple of S parameter caused by limited test frequency range by adjusting the test frequency range, without changing the length of measured piece in the whole calibration test process, thereby, without increasing the measurement cost and test complexity, effectively improves the accuracy and stability of S parameter parameter curve measurement in the field of electromagnetic measurement.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic measurement technology, and in particular to a method for testing S-parameters to suppress ripple, an electronic device, and a storage medium. Background Technology

[0002] Electromagnetic measurement is a crucial method for determining the electromagnetic properties of materials. With the advancement of science and technology, various fields, including radar navigation, aerospace, missile guidance, electronics, and new materials, are placing increasingly higher demands on the accuracy and stability of electromagnetic measurements. During electromagnetic measurements, S-parameters, as critical parameters, frequently exhibit ripple phenomena—that is, resonance, fluctuations, and abrupt changes in the S-parameter curve—which reduce the accuracy and stability of the measurement results. Therefore, suppressing S-parameter ripple during electromagnetic measurements to ensure the accuracy and stability of the results is of paramount importance. Summary of the Invention

[0003] This invention provides a method, electronic device, and storage medium for S-parameter testing to suppress ripple, which addresses the shortcomings of existing electromagnetic measurement processes where S-parameter ripple occurs. By adjusting the test frequency range, the ripple caused by the limitation of the test frequency range on the S-parameter is suppressed. Throughout the calibration and testing process, there is no need to change the length of the test piece. Thus, without increasing the measurement cost and testing complexity, the accuracy and stability of S-parameter parameter curve measurement in the field of electromagnetic measurement are effectively improved.

[0004] This invention provides an S-parameter testing method for suppressing ripple, applied to a parameter testing system. The parameter testing system includes a vector network analyzer, a coaxial cable, and a device under test (DUT), with the two ends of the coaxial cable connected to the vector network analyzer and the DUT, respectively. The method includes:

[0005] Based on a preset scanning power and a preset number of scanning points, the vector network analyzer is controlled to perform calibration and frequency sweep tests on the device under test within the test frequency range of the device under test, thereby determining the S-parameters of the device under test.

[0006] If ripple exists in the S-parameters, the test frequency range should be reduced.

[0007] The reduced test frequency range is used as the new test frequency range for the device under test, and the above steps are repeated until the S-parameter without ripple is determined as the target S-parameter of the device under test after ripple suppression.

[0008] According to the S-parameter testing method for suppressing ripple provided by the present invention, the method further includes:

[0009] When the test piece is being tested for S-parameters for the first time, the maximum test frequency is determined with the goal that the length of the test piece is greater than the preset operating wavelength of the test piece at the maximum test frequency.

[0010] The minimum scanning frequency of the vector network analyzer is determined as the minimum test frequency;

[0011] The test frequency range of the device under test is determined based on the minimum test frequency and the maximum test frequency.

[0012] According to the present invention, an S-parameter testing method for suppressing ripple is provided, wherein narrowing the test frequency range when ripple exists in the S-parameter includes:

[0013] If it is determined that there is ripple in the S-parameter, the highest test frequency in the test frequency range is reduced, and / or the lowest test frequency in the test frequency range is increased; to narrow the test frequency range; and the narrowed test frequency range belongs to the test frequency range before narrowing.

[0014] According to the S-parameter testing method for suppressing ripple provided by the present invention, reducing the highest test frequency in the test frequency range includes:

[0015] The length of the test piece is fixed, and the highest test frequency in the test frequency range is reduced so that the working wavelength of the test piece at the reduced highest test frequency is greater than the length of the test piece by H times; H≤0.5.

[0016] According to the S-parameter testing method for suppressing ripple provided by the present invention, increasing the lowest test frequency in the test frequency range includes:

[0017] The length of the test device is fixed, and the lowest test frequency in the test frequency range is increased so that the working wavelength of the test device at the increased lowest test frequency is less than the length of the test device by L times; L≥0.005, H>L.

[0018] According to the S-parameter testing method for suppressing ripple provided by the present invention, the method further includes:

[0019] If the parameter curve of the S-parameter is matched with the preset ripple-free parameter curve, and it is determined that the parameter curve of the S-parameter does not match the preset ripple-free parameter curve, then the S-parameter is determined to have ripple.

[0020] According to the S-parameter testing method for suppressing ripple provided by the present invention, the method further includes:

[0021] When an incident wave perpendicularly incident into the test piece undergoes multiple reflections and multiple transmissions through the test piece, a first ratio of the power of all reflected waves in the test piece to the power of the incident wave, and a second ratio of the power of all transmitted waves in the test piece to the power of the incident wave are determined.

[0022] The presence of ripple in the S-parameter is determined when the difference between the amplitude of the first ratio and 0 is minimized, and / or the difference between the amplitude of the second ratio and 1 is minimized.

[0023] According to the S-parameter testing method for suppressing ripple provided by the present invention, the process of determining the first ratio and the second ratio includes:

[0024] The first ratio and the second ratio are determined based on the reflection coefficient of the device under test, the length of the device under test, the effective dielectric constant of the device under test, the effective magnetic permeability of the device under test, and the propagation constant of the incident wave in the device under test.

[0025] Wherein, the effective dielectric constant and the effective permeability are both dielectric constants and permeabilities of media with the same electromagnetic properties as the test piece filled with a single medium or at least two media.

[0026] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the S-parameter testing method for suppressing ripple as described above.

[0027] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the S-parameter testing method for suppressing ripple as described above.

[0028] This invention provides a method, electronic device, and storage medium for S-parameter testing with ripple suppression. The method involves using an electronic device to control a vector network analyzer to calibrate and perform frequency sweep tests on the device under test (DUT) within its test frequency range. When ripple is detected in the S-parameters, the test frequency range is changed while maintaining the length of the DUT. Calibration and frequency sweep tests are repeated based on the adjusted test frequency range until the target S-parameters after ripple suppression are determined. This suppresses ripple caused by the test frequency range limitation by adjusting the test frequency range. The entire calibration and testing process does not require changing the length of the DUT, thus effectively improving the accuracy and stability of S-parameter curve measurements in the field of electromagnetic measurement without increasing measurement costs or complexity. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 This is a flowchart illustrating the S-parameter testing method for suppressing ripple provided by the present invention.

[0031] Figure 2 This is a schematic diagram of the S-parameter testing system provided by the present invention;

[0032] Figure 3A This is a cross-sectional schematic diagram of the coaxial line provided by the present invention;

[0033] Figure 3B This is a three-dimensional schematic diagram of the coaxial cable provided by the present invention;

[0034] Figure 4A This is a schematic cross-sectional view of the microstrip line provided by the present invention;

[0035] Figure 4B This is a three-dimensional schematic diagram of the microstrip line provided by the present invention;

[0036] Figure 5 This is a schematic diagram of the transmission process of the test device to the incident electromagnetic wave provided by the present invention.

[0037] Figure 6 This is a schematic diagram of the first two reflections and transmission responses of the test device to the incident electromagnetic wave provided by the present invention;

[0038] Figure 7 This is a schematic diagram of the transmission of electromagnetic waves through a three-layer structured medium provided by the present invention;

[0039] Figure 8 This is one of the schematic diagrams of the amplitude curve of the S-parameter of the coaxial line as the test object provided by the present invention;

[0040] Figure 9 This is the second schematic diagram of the amplitude curve of the S-parameter of the coaxial line as the test piece provided by the present invention;

[0041] Figure 10 This is one of the schematic diagrams of the amplitude curves of the S-parameters of the microstrip line as the device under test provided by the present invention;

[0042] Figure 11 This is the second schematic diagram of the amplitude curve of the S-parameter of the microstrip line as the device under test provided by the present invention;

[0043] Figure 12This is a schematic diagram of the S-parameter testing device for suppressing ripple provided by the present invention;

[0044] Figure 13 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0046] The following is combined with Figures 1-13 This invention describes a ripple suppression S-parameter testing method, electronic device, and storage medium. The ripple suppression S-parameter testing method is applied to a parameter testing system, which includes a vector network analyzer, a coaxial cable, and a device under test (DUT). The two ends of the coaxial cable are connected to the vector network analyzer and the DUT, respectively. Furthermore, the execution entity of the ripple suppression S-parameter testing method is an electronic device connected to the vector network analyzer in the parameter testing system. This electronic device possesses at least frequency range determination, frequency range adjustment, and calibration test control functions. The electronic device can be a personal computer (PC), laptop computer, tablet computer, or other devices. Further, the ripple suppression S-parameter testing method can also be applied to a ripple suppression S-parameter testing device installed in an electronic device. This ripple suppression S-parameter testing device can be implemented through software, hardware, or a combination of both. The following description uses an example where the execution entity of the ripple suppression S-parameter testing method is a controller built into an electronic device.

[0047] To facilitate understanding of the S-parameter testing method for ripple suppression provided in the embodiments of the present invention, the following will describe in detail the S-parameter testing method for ripple suppression provided by the present invention through several exemplary embodiments. It is understood that these exemplary embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0048] Reference Figure 1 The above is a flowchart illustrating the S-parameter testing method for suppressing ripple provided by the present invention. Figure 1 As shown, the S-parameter test method for suppressing ripple includes the following steps 110 to 130.

[0049] Step 110: Based on the preset scanning power and preset number of scanning points, control the vector network analyzer to perform calibration and frequency sweep tests on the device under test within the test frequency range of the device under test, and determine the S-parameters of the device under test.

[0050] The device under test can be a coaxial line or a microstrip line, and can be equivalent to a symmetrical two-port network; for example, refer to Figure 2 The schematic diagram of the parameter testing system shown illustrates how two different ports of the vector network analyzer can be connected to one end of two coaxial cables, as follows: Figure 2 As shown, the other ends of the two coaxial cables are connected to the two ports of the device under test (DUT) to simplify the analysis of the electromagnetic response of a homogeneous DUT. This invention does not impose a specific limitation on the length of the DUT. Furthermore, S-parameters (i.e., scattering parameters) can be used to evaluate the performance of the reflected and transmitted signals of the DUT.

[0051] Specifically, in step 110, the test frequency range of the device under test can be either the test frequency range of the device under test or the non-test frequency range of the device under test.

[0052] For the test frequency range of the device under test (DUT), the test frequency range that matches both the current medium filling material and the length of the current DUT can be determined from the pre-set and stored mapping relationship between medium filling material, length, and test frequency range. Here, each test frequency range in the medium filling material-length-test frequency range mapping relationship is a test frequency range containing ripple S-parameters that can be obtained on the first use of the vector network analyzer. Alternatively, the user can manually determine the initial test frequency of the DUT and input it into the electronic device. Input methods include, but are not limited to, input via terminal device applications, voice input, and image input. For example, the test frequency range can be obtained by the user manually inputting it into an application on another electronic device connected to the electronic device, by the user or other electronic devices outputting the test frequency range of the DUT via voice, or by uploading an image containing the test frequency range of the DUT to the electronic device for image recognition. No specific limitations are specified here.

[0053] In addition, for the non-test frequency range of the device under test, it can be determined based on the previous test frequency range of the non-test frequency range, such as the test frequency range obtained after adjusting the previous test frequency range.

[0054] Based on this, once the test frequency range of the device under test (DUT) is determined, the electronic device can control the vector network analyzer to start calibration and frequency sweep testing of the DUT within the test frequency range based on a preset scan power (e.g., 1W) and a preset number of scan points (e.g., 201). In other words, the electronic device can send a control command to the vector network analyzer to instruct it to start calibration and frequency sweep testing, thereby obtaining the S-parameters of the DUT.

[0055] It should be noted that, in order to facilitate the design of the characteristic impedance of the device under test, this invention uses the effective permittivity and effective permeability to represent the electromagnetic properties exhibited by the device under test in the test environment. When the coaxial line is used as the device under test, it is filled with a homogeneous medium, and its cross-sectional view is shown in the figure. Figure 3A As shown, the coaxial cable includes an inner conductor 301, a dielectric layer 302, an outer conductor 303, and a shielding layer 304. The dielectric constant and permeability of this dielectric are the effective dielectric constant and effective permeability of the coaxial cable. A three-dimensional schematic diagram of the coaxial cable is shown below. Figure 3B As shown, it includes an outer conductor, a shielding layer, an inner conductor, and a dielectric layer, as follows: Figure 3B As shown, both the inner and outer conductors are made of copper, and the intermediate dielectric material is polytetrafluoroethylene. The effective dielectric constant and effective permeability of the coaxial line are 2.1ε0 and μ0, respectively. The outer diameter of the coaxial line is 7 mm, the inner diameter is 3 mm, and the length is 15 mm. Here, ε0 represents the dielectric constant in vacuum, and μ0 represents the permeability in vacuum.

[0056] When a microstrip line is used as the device under test, it is filled with two or more dielectrics, and its cross-section is as follows: Figure 4A As shown, it includes a conductor strip 401, a ground plane 402, and a dielectric layer 403; a three-dimensional schematic diagram of the microstrip line is shown below. Figure 4B As shown, it includes a conductor strip, a dielectric layer, and a ground plane; in Figure 4B In this model, the conductor strip and the ground plane are both made of copper, the dielectric substrate is made of Rogers 5880, the effective permittivity and effective permeability of the microstrip line are 1.8ε0 and μ0, respectively, the conductor strip thickness is 35 μm, the conductor strip width is 0.6 mm, the dielectric substrate thickness is 0.508 mm, the ground plane thickness is 35 μm, the microstrip line width is 20 mm, and the microstrip line length is 50 mm. At this time, the effective permittivity and effective permeability of the microstrip line can be obtained by using the conformal mapping method. The solution process is shown in equations (1) and (2).

[0057]

[0058]

[0059] In equations (1) and (2), ε eff μ represents the effective dielectric constant. effε0 represents the effective permeability, ε0 represents the permittivity in vacuum, μ0 represents the permeability in vacuum, and q0 represents the air fill factor; q i (i = 1, 2, ..., n + m) represents the fill factor of the i-th layer of medium, satisfying: ε r(i) (i = 1, 2, ..., n + m) represents the relative permittivity of the i-th dielectric layer, μ r(i) (i = 1, 2, ..., n + m) represents the relative permeability of the i-th dielectric layer, n represents the number of dielectric layers below the conductor strip in the microstrip line, i.e., dielectric layers 1, 2, ..., n are below the conductor strip in the microstrip line, and m represents the number of dielectric layers above the conductor strip in the microstrip line, i.e., n + 1, n + 2, ..., n + m are above the conductor strip in the microstrip line.

[0060] Based on this, the parameter testing system provided in this invention is specifically a non-matching testing system, where the characteristic impedance of the device under test (DUT) is mismatched with the characteristic impedance of the signal source. This aims to increase the DUT's response to electromagnetic wave reflection and transmission. Furthermore, compared to a matched response, a mismatch between the DUT's characteristic impedance and the signal source's characteristic impedance increases both the reflection and transmission characteristics of the electromagnetic waves output by the vector network analyzer, and the amplitude fluctuation of the measured S-parameter curve also increases accordingly. In addition, the degree of mismatch between the DUT's characteristic impedance and the signal source's characteristic impedance is determined by the reflection coefficient R at both ends of the DUT; R = 0 indicates that the characteristic impedance of the DUT is mismatched with the signal source's characteristic impedance. The characteristic impedance of the signal source is matched. The greater the difference between the absolute value of R and 0, the greater the mismatch between the characteristic impedance of the device under test and the characteristic impedance of the signal source. If the absolute value of R is too large, the transmission characteristics of the device under test for incident electromagnetic waves will be extremely small. If the absolute value of R is too small, the reflection characteristics of the device under test for incident electromagnetic waves will be extremely small. Based on this, the value of R is preset in this invention and should not be too large or too small. Generally, the value range is |R| = 0.1-0.8. The characteristic impedance of the signal source is known. The value of R and the characteristic impedance of the signal source are used to determine the characteristic impedance of the device under test. The characteristic impedance of the device under test can be calculated by equation (3).

[0061]

[0062] In equation (3), R represents the reflection coefficient at both ends of the measured object, and Z... L Z represents the characteristic impedance of the measured component. C This represents the characteristic impedance of the signal source.

[0063] Subsequently, based on the already obtained characteristic impedance of the test device, the effective dielectric constant and effective permeability of the test device, and the characteristic impedance design formula of the test device shown in equations (4) to (7), the cross-sectional dimensions of the test device can be further obtained, thereby realizing the design of the cross-sectional dimensions of the unmatched test device.

[0064] When the coaxial line is used as the measured part, its cross-sectional dimensions (inner diameter a and outer diameter b of the coaxial line) can be determined by equation (4).

[0065]

[0066] In equation (4), The characteristic impedance of the coaxial line, ε eff μ represents the effective dielectric constant of the coaxial line. eff denoted by , b represents the effective permeability of the coaxial line, b represents the outer diameter of the coaxial line, and a represents the inner diameter of the coaxial line.

[0067] When a microstrip line is used as the device under test, its cross-sectional dimensions (the thickness of the dielectric substrate h and the width of the conductor strip w) can be determined by equations (5) to (7).

[0068]

[0069]

[0070]

[0071] In equations (5) to (7), ε represents the characteristic impedance of the microstrip line. eff μ represents the effective dielectric constant of the microstrip line. eff t' represents the effective permeability of the microstrip line, h represents the thickness of the dielectric substrate of the microstrip line, and t' represents the thickness of the conductor strip of the microstrip line.

[0072] Step 120: If there is ripple in the S-parameters, reduce the test frequency range.

[0073] Among them, the presence of ripple in the S-parameter can be at least one of the following: resonance, fluctuation, and abrupt change in the S-parameter curve.

[0074] Step 130: Use the reduced test frequency range as the new test frequency range, and repeat steps 110 and 120 until the S-parameters without ripple are determined as the target S-parameters of the device under test after ripple suppression.

[0075] Specifically, the S-parameters initially determined by the control vector network analyzer can be recorded as the first S-parameters, and it is determined that the first S-parameters must have ripple. When the electronic device obtains the first S-parameters of the device under test through the control vector network analyzer, it can be determined that there is ripple and the initially determined test frequency range can be adjusted, that is, the test frequency range can be narrowed, and the narrowed test frequency range can be used as the new test frequency range. Then, the process returns to steps 110 and 120.

[0076] Conversely, if it is determined that the S-parameter is not the first one, it can be recorded as the second S-parameter. The parameter curve of the second S-parameter can be further analyzed to determine whether the parameter curve of the second S-parameter has at least one of the following conditions: resonance, fluctuation, and abrupt change. If it is determined that the parameter curve of the second S-parameter does not have resonance, fluctuation, or abrupt change, it can be determined that it does not have ripple, and the second S-parameter without ripple is determined as the target S-parameter of the device under test after ripple suppression. Conversely, if it is determined that the parameter curve of the second S-parameter has at least one of the following conditions: resonance, fluctuation, and abrupt change, it can be determined that the second S-parameter has ripple, and the test frequency range corresponding to the second S-parameter with ripple is adjusted, that is, the test frequency range is narrowed, and the narrowed test frequency range is used as the new test frequency range. Then, return to steps 110 and 120; until the target S-parameter of the device under test after ripple suppression is determined.

[0077] It should be noted that since the characteristic impedance of the device under test (DUT) is mismatched with the characteristic impedance of the signal source, this mismatch can be used to amplify the appearance and suppression of ripple without changing its presence. By adjusting the test frequency range of the DUT, a method to suppress S-parameter ripple can be obtained. That is, within the test frequency range, the ratio of the length of the DUT to its operating wavelength should be kept between L and H, where L represents the minimum ratio of the length of the DUT to its operating wavelength and H represents the maximum ratio of the length of the DUT to its operating wavelength.

[0078] The S-parameter testing method for ripple suppression provided in this invention involves using an electronic device to calibrate and perform frequency sweep tests on the device under test (DUT) within its test frequency range using a control vector network analyzer. When ripple is detected in the S-parameters, the test frequency range is changed while maintaining the length of the DUT. Calibration and frequency sweep tests are repeated based on the adjusted test frequency range until the target S-parameters after ripple suppression are determined. This method suppresses ripple caused by the limitation of the test frequency range by adjusting the test frequency range. The entire calibration and testing process does not require changing the length of the DUT, thus effectively improving the accuracy and stability of S-parameter curve measurements in the field of electromagnetic measurement without increasing measurement costs or complexity.

[0079] Based on the above Figure 1 The S-parameter testing method for suppressing ripple, as shown in the example embodiment, for the first S-parameter test of the device under test (DUT), the test frequency range of the DUT can be determined based on the relationship between the operating wavelength of the DUT at different test frequencies and the length of the DUT, as well as the scanning frequency of the vector network analyzer. Based on this, the S-parameter testing method for suppressing ripple provided in this embodiment of the invention may further include:

[0080] First, when the test device is undergoing S-parameter testing for the first time, the maximum test frequency is determined with the goal that the length of the test device is greater than the preset operating wavelength of the test device at the maximum test frequency; and the minimum scanning frequency of the vector network analyzer is determined as the minimum test frequency; then, based on the minimum test frequency and the maximum test frequency, the test frequency range of the test device is determined.

[0081] Specifically, when it is determined that the device under test (DUT) is undergoing S-parameter testing for the first time, the highest test frequency can be determined with the goal that half of the operating wavelength of the DUT at the highest test frequency within the test frequency range is less than the length of the DUT. The lowest test frequency within the test frequency range can be determined as the lowest scanning frequency of the vector network analyzer. The highest test frequency is greater than the lowest test frequency. The test frequency range obtained in this way, which includes the lowest test frequency and the highest test frequency, can be the test frequency range of the DUT.

[0082] It should be noted that the reason for setting the test frequency range in this invention is to ensure that the S-parameters obtained by the vector network analyzer in the first test using this test frequency range will definitely have ripple, so that the target S-parameters without ripple can be quickly and accurately determined by adjusting the test frequency range in the future.

[0083] Based on the above Figure 1 The S-parameter testing method for suppressing ripple, as shown in one example embodiment, allows for adjusting the test frequency range corresponding to S-parameters exhibiting ripple by adjusting at least one of the two extreme values ​​within that range. Based on this, narrowing the test frequency range when S-parameters exhibit ripple can be achieved through a specific implementation process that includes:

[0084] If ripple is found in the S-parameters, the highest test frequency in the test frequency range is reduced, and / or the lowest test frequency in the test frequency range is increased; to narrow the test frequency range; and the narrowed test frequency range belongs to the test frequency range before narrowing.

[0085] Specifically, when S-parameters exhibit ripple, the test frequency range corresponding to the presence of ripples can be reduced according to a preset adjustment range. This adjustment can be an increase or a decrease. For example, if the test frequency range is determined to be the ratio of the length of the test piece to the working wavelength, and S-parameters exhibit ripples, the adjustment range can be set to 0.01 from the preset adjustment range [0.01, 0.02]. This allows for a reduction from [0.1, 0.5] to [0.11, 0.5], [0.1, 0.49], or [0.11, 0.49], thereby achieving the goal of gradually reducing the test frequency range corresponding to the presence of ripples in the S-parameters.

[0086] Based on the above Figure 1 The S-parameter testing method for suppressing ripple, as shown in one example embodiment, involves reducing the highest test frequency in the test frequency range corresponding to the presence of ripple in the S-parameters. The specific determination process may include:

[0087] With the length of the test piece fixed, the highest test frequency in the test frequency range corresponding to the presence of S-parameter ripple is reduced so that H times the operating wavelength of the test piece at the reduced highest test frequency is greater than the length of the test piece; H ≤ 0.5. Furthermore, the highest test frequency in the test frequency range corresponding to the presence of S-parameter ripple is f. max The minimum test frequency is f min At that time, f max >f min f max <100f min ,

[0088] Based on the above Figure 1 The S-parameter testing method for suppressing ripple, as shown in one example embodiment, involves increasing the lowest test frequency in the test frequency range corresponding to the presence of ripple in the S-parameter. The specific determination process may include:

[0089] With the length of the test piece fixed, the lowest test frequency in the test frequency range corresponding to the presence of ripple in the S-parameter is increased so that the working wavelength of the test piece at the increased lowest test frequency is less than the length of the test piece by L times; L≥0.005, H>L.

[0090] It should be noted that the reason for adjusting the test frequency range corresponding to the presence of ripple in the S-parameters is to avoid the length of the test piece being equal to or close to an integer multiple of half the wavelength within the test frequency range. If the length of the test piece is equal to or close to an integer multiple of half the working wavelength at a certain frequency within the test frequency range, the S-parameter curve will exhibit phenomena such as resonance, fluctuation, and abrupt changes, that is, the S-parameter curve will show ripple. The reason for this phenomenon is also the reason for adjusting the test frequency range to avoid ripple in the S-parameter curve. This reason can be analyzed from three aspects: phase superposition and cancellation, multi-layer media propagation, and transmission reflection theory.

[0091] For S-parameter phase superposition and cancellation, considering that the electromagnetic wave is incident perpendicularly on the test object and undergoes multiple reflections and transmissions through the test object, the electromagnetic wave transmission process is as follows: Figure 5 As shown, with the increase of the number of transmissions, the phase of the electromagnetic wave gradually increases, but the intensity gradually decreases. Therefore, phase superposition and cancellation only determine the phase difference between the secondary reflected wave and the primary reflected wave, and the phase difference between the secondary transmitted wave and the primary transmitted wave, to obtain the superposition and cancellation of the amplitudes of the reflected wave and the transmitted wave. Figure 6 This is a schematic diagram of the first two reflections and transmission responses of the device under test to an incident electromagnetic wave.

[0092] According to the principle and characteristics of electromagnetic wave transmission, the phase difference between multiple reflected waves and the first reflected wave, and the phase difference between multiple transmitted waves and the first transmitted wave can be expressed by equations (8) and (9).

[0093]

[0094]

[0095] In equations (8) and (9), Indicates the phase difference of the reflected wave. ω represents the phase difference of the transmitted wave, t represents the time it takes for the electromagnetic wave to pass through the test piece, l represents the length of the test piece, and λ represents the working wavelength.

[0096] Based on the phase difference between the secondary reflected wave and the primary reflected wave, and the phase difference between the secondary transmitted wave and the primary transmitted wave, it is found that when the length of the measured object is half the wavelength or an integer multiple thereof, the reflected waves cancel each other out to the maximum extent and have the smallest amplitude, while the transmitted waves are superimposed in phase to the maximum extent and have the largest amplitude.

[0097] For propagation in multi-layered media, we consider electromagnetic waves incident perpendicularly to the test object, and there is no limitation on the number of layers in the media structure. Here, we take a three-layered media structure as an example, and the conclusions can be applied to multi-layered media structures. The propagation process of electromagnetic waves in a three-layered media structure is as follows: Figure 7As shown, from left to right, they are medium 1, medium 2 and medium 3. Medium 1 and medium 3 are semi-infinite media, which are close to the electromagnetic measurement conditions, and the electromagnetic waves are incident perpendicularly.

[0098] like Figure 7 As shown, the three-layer structure medium has two media interfaces, interface 1 and interface 2, which affect the transmission of electromagnetic waves. The reflection coefficient and transmission coefficient of each interface are shown in equations (10) to (14).

[0099]

[0100]

[0101]

[0102]

[0103] In equations (10) to (14), R2 represents the reflection coefficient at interface 2, τ2 represents the transmission coefficient at interface 2, R1 represents the reflection coefficient at interface 1, τ1 represents the transmission coefficient at interface 1, η1 represents the wave impedance of medium 1, η2 represents the wave impedance of medium 2, η3 represents the wave impedance of medium 3, γ2 represents the propagation constant of the electromagnetic wave in medium 2, and l2 represents the length of medium 2; η ef The equivalent wave impedance of media 2 and media 3 at interface 1 can be expressed as:

[0104]

[0105] When the length of the middle medium in a three-layer medium structure is half the working wavelength or an integer multiple thereof, and the wave impedances η1 and η3 of the other two media are the same, electromagnetic waves can pass through the three-layer medium structure without loss. At this time, all incident electromagnetic waves pass through the device under test and there are no reflected waves. Based on the electromagnetic wave transmission analysis of the three-layer medium structure, it can be extended to the electromagnetic wave transmission analysis of structures with more than three layers of media.

[0106] For the transmission reflection method, considering the electromagnetic wave incident perpendicularly on the test object, the test object's response to multiple reflections and transmissions of the incident electromagnetic wave is as follows: Figure 5 As shown, the ratio S of all reflected wave power to incident wave power 11 The ratio S of all transmitted wave power to incident wave power 21 It can be expressed as equations (15) to (17).

[0107]

[0108]

[0109]

[0110] In equations (15) to (17), R represents the reflection coefficients at both ends of the measured component, γ represents the propagation constant of the incident wave in the measured component, l represents the length of the measured component, ω represents the angular frequency, and μ represents the reflection coefficients at both ends of the measured component. eff ε represents the effective permeability of the measured component. eff This represents the effective dielectric constant of the device under test.

[0111] According to the theory and formula of the transmission reflection method, if the length of the measured object is half the working wavelength or an integer multiple thereof, the transmission coefficient amplitude is 1. In this case, S... 11 The minimum amplitude is 0, S 21 The maximum amplitude is 1.

[0112] In the field of electromagnetic measurement, to better describe and calculate S-parameters, the unit for representing S-parameters is dB, where S... 11 When the amplitude is close to 0, if expressed in dB, S 11 The magnitude of S approaches negative infinity (-∞); 21 When the amplitude is close to 1, if expressed in dB, S 21 The amplitude is close to 0. Based on this, it can be concluded that when the length of the tested component is equal to or close to half the working wavelength or an integer multiple thereof within the test frequency range, the amplitude of all reflected electromagnetic waves is minimal, S 11 Using dB representation, which is close to -∞, will cause the S-parameter curve to deviate from the normal value, such as resonance, fluctuation and abrupt change, that is, the S-parameter will exhibit ripple phenomenon.

[0113] Since ripple appears in the S-parameter curve when the length of the measured component is equal to or close to an integer multiple of half the working wavelength, the values ​​of H and L should be H < 0.5 and L > 0, with H > L. However, 0.5 and 0 represent extreme cases and cannot effectively suppress the ripple in the S-parameter curve. Based on this, and through extensive simulations and actual tests, it was determined that when H ≤ 0.45, L ≥ 0.005, and H > L, the ripple in the S-parameter curve can be effectively suppressed.

[0114] Based on the above Figure 1 The S-parameter testing method for suppressing ripple, as shown in one example embodiment, determines whether ripple exists in the S-parameter by matching the parameter curve of the currently determined S-parameter with the parameter curve of the ripple-free standard parameter when the electronic device has pre-stored the parameter curve of the S-parameter. Based on this, the S-parameter testing method for suppressing ripple provided by the present invention may further include:

[0115] If the parameter curve of the S-parameter is matched with the preset ripple-free parameter curve, and it is determined that the parameter curve of the S-parameter does not match the preset ripple-free parameter curve, then the S-parameter is determined to have ripple.

[0116] Specifically, the preset ripple-free parameter curve can be a standard parameter curve in which the S-parameters do not exhibit resonance, fluctuation, or abrupt changes.

[0117] Specifically, in order to improve the efficiency of determining whether there is ripple in the S-curve, a preset ripple-free parameter curve that characterizes the absence of ripple in the S-parameters can be pre-set and stored, and then matched with the S-parameters obtained in the current test. If the parameter curve of the S-parameters obtained in the current test does not match the preset ripple-free parameter curve, then it is determined that there is ripple in the S-parameters obtained in the current test.

[0118] It should be noted that if the S-parameters obtained from the current test are matched with the preset ripple-free parameter curve, then the S-parameters obtained from the current test are the target S-parameters after the ripple of the test piece is suppressed.

[0119] For example, will Figure 3B The coaxial cable shown is used as the test object, meaning that both the inner and outer conductors are made of copper, and the intermediate dielectric material is polytetrafluoroethylene (PTFE). The effective dielectric constant and effective permeability of the coaxial cable are 2.1ε₀ and μ₀, respectively. The outer diameter of the coaxial cable is 7 mm, the inner diameter is 3 mm, and the length is 15 mm. Under these conditions, with a test frequency range of 50 MHz–40 GHz, a preset scan power of 1 W, and a preset scan point count of 201, the following results can be obtained: Figure 8 The diagram shown illustrates the amplitude curve of the S-parameters of the coaxial line as the measured component, with units in dB.

[0120] By maintaining a coaxial cable length of 15mm, adjusting the test frequency range to 200MHz–5GHz, setting the preset scan power to 1W, and the preset scan point count to 201, the following results can be obtained: Figure 9 The diagram shown illustrates the amplitude curve of the S-parameters of the coaxial line as the measured component, with units in dB.

[0121] Will Figure 4B The microstrip line shown is used as the device under test, such as Figure 4B As shown, the microstrip line is filled with two dielectric materials: copper for both the conductor strip and the ground plane, i.e., Rogers 5880 for the dielectric substrate. The effective dielectric constant and effective permeability of the microstrip line are 1.8ε0 and μ0, respectively. The conductor strip thickness is 35 μm, the conductor strip width is 0.6 mm, the dielectric substrate thickness is 0.508 mm, the ground plane thickness is 35 μm, the microstrip line width is 20 mm, and the microstrip line length is 50 mm. At this point, with a test frequency range of 50 MHz–10 GHz, a preset scan power of 1 W, and a preset scan point count of 201, the following results can be obtained: Figure 10 The diagram shown is a schematic of the amplitude curve of the S-parameters of the microstrip line as the device under test, with units in dB.

[0122] By maintaining a microstrip line length of 50mm, adjusting the test frequency range to 50MHz-1.8GHz, setting the preset scan power to 1W, and the preset scan point count to 201, the following results can be obtained: Figure 11 The diagram shown is a schematic of the amplitude curve of the S-parameters of the microstrip line as the device under test, with units in dB.

[0123] Based on the above Figure 1 The S-parameter testing method for suppressing ripple, as shown in one example embodiment, involves an electromagnetic wave perpendicularly incident on the test piece (DPT) and transmitted multiple times within the DPT via multiple reflections and transmissions. The presence of ripple in the S-parameters obtained from this test can be determined based on the relationship between the reflected wave, the transmitted wave, and the incident wave. Therefore, the S-parameter testing method for suppressing ripple provided in this embodiment of the invention may further include:

[0124] First, when an incident wave perpendicularly incident into the test piece undergoes multiple reflections and multiple transmissions through the test piece, a first ratio of the power of all reflected waves in the test piece to the power of the incident wave, and a second ratio of the power of all transmitted waves in the test piece to the power of the incident wave are determined. Then, when the difference between the amplitude of the first ratio and 0 is minimized, and / or the difference between the amplitude of the second ratio and 1 is minimized, it is determined that the S-parameters of the test piece have ripple.

[0125] Specifically, the difference between the amplitude of the first ratio and 0 is minimized; specifically, the first ratio is close to 0. In dB terms, this means the amplitude of the first ratio is close to negative infinity (-∞). Similarly, the difference between the amplitude of the second ratio and 1 is minimized; specifically, the second ratio is close to 1. In dB terms, this means the amplitude of the second ratio is close to 0. At least one of these two situations will cause the S-parameter curve to deviate from its normal value, exhibiting resonance, fluctuations, or abrupt changes—that is, ripple in the S-parameters. Therefore, when an incident wave perpendicularly incident on the test device undergoes multiple reflections and transmissions, the presence of ripple in the S-parameters of the test device can be determined by minimizing the difference between the amplitude of the first ratio of the power of all reflected waves in the test device to the power of the incident wave and 0, and / or minimizing the difference between the amplitude of the second ratio of the power of all transmitted waves in the test device to the power of the incident wave and 1. This improves the flexibility and accuracy of determining whether ripple exists in the S-parameters.

[0126] Based on the above Figure 1The S-parameter testing method for suppressing ripple, as shown in one example embodiment, determines the effective dielectric constant and effective permeability of the corresponding device under test (DUT) by determining the dielectric constant and permeability of a medium with the same electromagnetic properties as the DUT, when the DUT is filled with a single dielectric (such as a coaxial line) or at least two dielectrics (such as a microstrip line). Based on this, the first ratio and the second ratio are determined. The specific determination process may include:

[0127] The first ratio and the second ratio are determined based on the reflection coefficient of the test device, the length of the test device, the effective dielectric constant of the test device, the effective magnetic permeability of the test device, and the propagation constant of the incident wave in the test device.

[0128] The effective dielectric constant and effective permeability are the dielectric constant and permeability of a medium with the same electromagnetic properties as the test piece filled with a single medium or at least two media.

[0129] Specifically, this first ratio is the ratio S of all reflected wave power to incident wave power. 11 The second ratio is specifically the ratio S of all transmitted wave power to incident wave power. 21 In the case of [the aforementioned situation], the first ratio and the second ratio can be determined using equations (15) to (17) in the foregoing embodiments. The specific determination process and related diagrams can be found in the foregoing embodiments. They will not be repeated here.

[0130] The S-parameter testing device for suppressing ripple provided by the present invention will be described below. The S-parameter testing device for suppressing ripple described below can be referred to in correspondence with the S-parameter testing method for suppressing ripple described above.

[0131] The S-parameter testing device for suppressing ripple provided by the present invention is applied to a parameter testing system, which includes a vector network analyzer, a coaxial cable and a device under test, with the two ends of the coaxial cable connected to the vector network analyzer and the device under test, respectively.

[0132] Reference Figure 12 The diagram below shows the structure of the S-parameter testing device for suppressing ripple provided by the present invention. Figure 12 As shown, the S-parameter testing device 1200 for suppressing ripple includes: a control testing module 1210 and a frequency range adjustment module 1220.

[0133] The control test module 1210 is used to control the vector network analyzer to perform calibration and frequency sweep tests on the device under test within the test frequency range of the device under test based on the preset scan power and preset scan points, and to determine the S-parameters of the device under test.

[0134] The frequency range adjustment module 1220 is used to narrow the test frequency range when there is ripple in the S-parameters; and to use the narrowed test frequency range as the new test frequency range of the device under test, and to repeatedly execute the steps of controlling the vector network analyzer to calibrate and sweep the test device under test within the test frequency range of the device under test based on the preset scan power and preset scan points, and to determine the S-parameters of the device under test; until the S-parameters without ripple are determined as the target S-parameters of the device under test after ripple suppression.

[0135] Optionally, the control test module 1210 is specifically used to determine the maximum test frequency when the test device is being tested for the first time, with the target being that the length of the test device is greater than the preset operating wavelength of the test device at the highest test frequency; to determine the minimum scanning frequency of the vector network analyzer as the minimum test frequency; and to determine the test frequency range of the test device based on the minimum test frequency and the maximum test frequency.

[0136] Optionally, the frequency range adjustment module 1220 is specifically used to reduce the highest test frequency in the test frequency range and / or increase the lowest test frequency in the test frequency range when it is determined that there is ripple in the S-parameter; so as to narrow the test frequency range; and the narrowed test frequency range belongs to the test frequency range before narrowing.

[0137] Optionally, the frequency range adjustment module 1220 is used to fix the length of the test piece and reduce the highest test frequency in the test frequency range so that the working wavelength of the test piece at the reduced highest test frequency is greater than the length of the test piece; H≤0.5.

[0138] Optionally, the frequency range adjustment module 1220 is used to fix the length of the test piece and increase the lowest test frequency in the test frequency range so that the working wavelength of the test piece at the increased lowest test frequency is less than the length of the test piece; L≥0.005, H>L.

[0139] Optionally, the frequency range adjustment module 1220 is specifically used to determine that there is ripple in the S-parameter when the parameter curve of the S-parameter is matched with the preset ripple-free parameter curve and it is determined that the parameter curve of the S-parameter does not match the preset ripple-free parameter curve.

[0140] Optionally, the frequency range adjustment module 1220 is specifically used to determine, when the incident wave perpendicularly incident into the test piece undergoes multiple reflections and multiple transmissions through the test piece, a first ratio of the power of all reflected waves in the test piece to the power of the incident wave, and a second ratio of the power of all transmitted waves in the test piece to the power of the incident wave; and to determine that ripple exists in the S-parameter when the difference between the amplitude of the first ratio and 0 is minimized, and / or the difference between the amplitude of the second ratio and 1 is minimized.

[0141] Optionally, the frequency range adjustment module 1220 is specifically used to determine the first ratio and the second ratio based on the reflection coefficient of the test device, the length of the test device, the effective dielectric constant and the effective permeability of the test device, and the propagation constant of the incident wave in the test device; wherein the effective dielectric constant and the effective permeability are both dielectric constants and permeabilities of media with the same electromagnetic properties as the test device filled with a single medium or at least two media.

[0142] The S-parameter testing device 1200 for suppressing ripple provided in this embodiment of the invention can execute the technical solution in any embodiment of the above-described S-parameter testing method for suppressing ripple. Its implementation principle and specific implementation process are similar to those of the S-parameter testing method for suppressing ripple. Please refer to the implementation principle and specific implementation process of the S-parameter testing method for suppressing ripple, which will not be repeated here.

[0143] Figure 13 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 13 As shown, the electronic device may include: a processor 1310, a communication interface 1320, a memory 1330, and a communication bus 1340, wherein the processor 1310, the communication interface 1320, and the memory 1330 communicate with each other through the communication bus 1340. The processor 1310 can call logic instructions in the memory 1330 to execute an S-parameter test method for ripple suppression, the method including:

[0144] Based on the preset scanning power and preset number of scanning points, the vector network analyzer is controlled to perform calibration and frequency sweep tests on the device under test (DUT) within the test frequency range to determine the S-parameters of the DUT. If ripple exists in the S-parameters, the test frequency range is narrowed. The narrowed test frequency range is used as the new test frequency range for the DUT, and the above steps are repeated until the S-parameters without ripple are determined as the target S-parameters of the DUT after ripple suppression.

[0145] Furthermore, the logical instructions in the aforementioned memory 1330 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0146] On the other hand, the present invention also provides a computer program product, the computer program product comprising a computer program that can be stored on a non-transitory computer-readable storage medium, wherein when the computer program is executed by a processor, the computer is capable of executing the S-parameter testing method for ripple suppression provided by the above methods, the method comprising:

[0147] Based on the preset scanning power and preset number of scanning points, the vector network analyzer is controlled to perform calibration and frequency sweep tests on the device under test (DUT) within the test frequency range to determine the S-parameters of the DUT. If ripple exists in the S-parameters, the test frequency range is narrowed. The narrowed test frequency range is used as the new test frequency range for the DUT, and the above steps are repeated until the S-parameters without ripple are determined as the target S-parameters of the DUT after ripple suppression.

[0148] In another aspect, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the S-parameter testing method for suppressing ripple provided by the methods described above, the method comprising:

[0149] Based on the preset scanning power and preset number of scanning points, the vector network analyzer is controlled to perform calibration and frequency sweep tests on the device under test (DUT) within the test frequency range to determine the S-parameters of the DUT. If ripple exists in the S-parameters, the test frequency range is narrowed. The narrowed test frequency range is used as the new test frequency range for the DUT, and the above steps are repeated until the S-parameters without ripple are determined as the target S-parameters of the DUT after ripple suppression.

[0150] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0151] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0152] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for testing S-parameters to suppress ripple, characterized in that, The method is applied to a parameter testing system, which includes a vector network analyzer, a coaxial cable, and a device under test (DUT), wherein the two ends of the coaxial cable are respectively connected to the vector network analyzer and the DUT; the method includes: Based on a preset scanning power and a preset number of scanning points, the vector network analyzer is controlled to perform calibration and frequency sweep tests on the device under test within the test frequency range of the device under test, thereby determining the S-parameters of the device under test. If ripple is found in the S-parameter, the length of the test piece is fixed, the highest test frequency in the test frequency range is decreased, and / or the lowest test frequency in the test frequency range is increased to obtain a reduced test frequency range, which is a subset of the original test frequency range. Specifically, decreasing the highest test frequency in the test frequency range results in the test piece operating at the reduced highest test frequency. H The working wavelength is greater than the length of the test piece. H ≤0.5; Increase the lowest test frequency in the test frequency range so that the device under test is at the increased lowest test frequency. L The working wavelength is less than the length of the test piece. L ≥0.005, H > L ; The reduced test frequency range is used as the new test frequency range for the device under test, and the above steps are repeated until the S-parameter without ripple is determined as the target S-parameter of the device under test after ripple suppression.

2. The S-parameter testing method for suppressing ripple according to claim 1, characterized in that, The method further includes: When the test piece is being tested for S-parameters for the first time, the maximum test frequency is determined with the goal that the length of the test piece is greater than the preset operating wavelength of the test piece at the maximum test frequency. The minimum scanning frequency of the vector network analyzer is determined as the minimum test frequency; The test frequency range of the device under test is determined based on the minimum test frequency and the maximum test frequency.

3. The S-parameter testing method for suppressing ripple according to claim 1 or 2, characterized in that, The method further includes: If the parameter curve of the S-parameter is matched with the preset ripple-free parameter curve, and it is determined that the parameter curve of the S-parameter does not match the preset ripple-free parameter curve, then the S-parameter is determined to have ripple.

4. The S-parameter testing method for suppressing ripple according to claim 1 or 2, characterized in that, The method further includes: When an incident wave perpendicularly incident into the test piece undergoes multiple reflections and multiple transmissions through the test piece, a first ratio of the power of all reflected waves in the test piece to the power of the incident wave, and a second ratio of the power of all transmitted waves in the test piece to the power of the incident wave are determined. The presence of ripple in the S-parameter is determined when the difference between the amplitude of the first ratio and 0 is minimized, and / or the difference between the amplitude of the second ratio and 1 is minimized.

5. The S-parameter testing method for suppressing ripple according to claim 4, characterized in that, The process of determining the first ratio and the second ratio includes: The first ratio and the second ratio are determined based on the reflection coefficient of the device under test, the length of the device under test, the effective dielectric constant of the device under test, the effective magnetic permeability of the device under test, and the propagation constant of the incident wave in the device under test. Wherein, the effective dielectric constant and the effective permeability are both dielectric constants and permeabilities of media with the same electromagnetic properties as the test piece filled with a single medium or at least two media.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the S-parameter test method for suppressing ripple as described in any one of claims 1 to 5.

7. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the S-parameter testing method for suppressing ripple as described in any one of claims 1 to 5.

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