Low-level swept field test method, device, computer equipment, readable storage medium and program product

Abstract

The application relates to a low-level swept field test method and device, computer equipment, a computer readable storage medium and a computer program product. The method comprises the following steps: acquiring multiple preset polarization modes of a transmitting antenna, multiple preset illumination angles, and a reference electric field intensity corresponding to each preset polarization mode; for a preset combination formed by different preset polarization modes and different preset illumination angles, acquiring a received electric field intensity of an electric field in a first electromagnetic wave received by a receiving antenna under the condition that the transmitting antenna transmits an electromagnetic wave with a preset intensity based on the preset combination; and determining a target shielding coefficient of a measured system based on the received electric field intensity corresponding to the preset combination in which the preset polarization mode is located and the reference electric field intensity corresponding to the preset polarization mode. The method provided by the application can make the determined shielding coefficient more accurate.

Description

Technical Field

[0001] This application relates to the field of aircraft system-level HIRF testing technology, and in particular to a low-level sweep field testing method, apparatus, computer equipment, computer-readable storage medium, and computer program product. Background Technology

[0002] To determine an aircraft's immunity to external electric fields and ensure its continued normal operation after exposure to high-intensity electromagnetic fields, high-intensity radiated fields (HIRF) tests are required.

[0003] Existing technology proposes a low-level sweep method to obtain the transfer function of the aircraft-wide HIRF environment. This method employs a low-level sweep field test within the 100MHz~18GHz frequency band to obtain the aircraft's shielding coefficient, thereby calculating the magnitude of the internal electric field strength under external HIRF conditions. Finally, the attenuated electric field strength is used to conduct HIRF tests on the aircraft's internal equipment, thus replacing the full-aircraft HIRF test. However, this method lacks detailed descriptions of the test system requirements and methods, leading to numerous problems in practical engineering applications and potentially resulting in inaccurate aircraft shielding coefficients. Summary of the Invention

[0004] Therefore, it is necessary to provide a low-level sweep field test method, apparatus, computer equipment, computer-readable storage medium, and computer program product that can accurately determine the shielding coefficient of an aircraft system, addressing the aforementioned technical problems.

[0005] In a first aspect, this application provides a low-level swept field test method, the method comprising:

[0006] Given the positional relationship between the transmitting antenna located outside the system under test and the receiving antenna located inside the system under test, and provided that the preset positional relationship is satisfied, obtain multiple preset polarization modes, multiple preset illumination angles, and the corresponding reference electric field strength for each preset polarization mode; wherein, the polarization mode is used to determine the vector direction of the electric field in the electromagnetic wave emitted by the transmitting antenna, and the illumination angle is used to determine the propagation direction of the electromagnetic wave emitted by the transmitting antenna.

[0007] For preset combinations formed by different preset polarization methods and different preset illumination angles, when the transmitting antenna transmits electromagnetic waves of preset intensity based on the preset combination, the received electric field intensity of the electric field in the first electromagnetic wave received by the receiving antenna is obtained, and the received electric field intensity is determined as the corresponding received electric field intensity of the preset combination.

[0008] Based on the received electric field strength corresponding to the preset combination of preset polarization mode and the reference electric field strength corresponding to the preset polarization mode, the target shielding coefficient of the system under test is determined; whereby the shielding coefficient characterizes the shielding capability of the system under test against external electric fields.

[0009] In one embodiment, the preset positional relationship is as follows: the height of the first preset point on the transmitting antenna relative to the ground is a first preset height; the height of the second preset point on the receiving antenna relative to the ground is a second preset height; the distance between the first preset point and the second preset point is a preset distance; and both the transmitting antenna and the receiving antenna are within a preset test range.

[0010] In one embodiment, obtaining the reference electric field intensity corresponding to each preset polarization mode includes:

[0011] Under the conditions that the height of the first preset point relative to the ground is the first preset height, the height of the second preset point relative to the ground is the second preset height, the distance between the first preset point and the second preset point is the preset distance, and both the transmitting antenna and the receiving antenna are outside the system under test and within the preset test range, the reference illumination angle of the transmitting antenna is obtained.

[0012] For a reference combination formed by a preset polarization mode and a reference illumination angle, when the transmitting antenna transmits electromagnetic waves of a preset intensity based on the reference combination, the initial frequency domain signal of the second electromagnetic wave received by the receiving antenna is obtained, and the initial frequency domain signal is inversely transformed to obtain multiple consecutive initial time domain signals.

[0013] Obtain a preset time period and determine the signal within the preset time period from multiple consecutive initial time domain signals as the target time domain signal;

[0014] A forward transform is performed on the target time-domain signal to obtain the target frequency-domain signal, and the corresponding electric field intensity of the target frequency-domain signal is determined as the reference electric field intensity corresponding to the preset polarization mode.

[0015] In one embodiment, the second electromagnetic wave includes a direct wave and a reflected wave; wherein the direct wave is the electromagnetic wave directly received by the receiving antenna and emitted by the transmitting antenna, and the reflected wave is the electromagnetic wave reflected outward by a reflecting object based on the received electromagnetic wave emitted by the transmitting antenna; obtaining a preset time period includes:

[0016] Obtain the first reception time when the receiving antenna receives the direct wave, and the second reception time when it receives the reflected wave;

[0017] The time interval between the first reception time and the second reception time is obtained, and the time interval centered on the first reception time and with the time interval as the duration is determined as the preset time interval.

[0018] In one embodiment, the target shielding coefficient of the system under test is determined based on the received electric field strength corresponding to the preset combination of preset polarization and the reference electric field strength corresponding to the preset polarization, including:

[0019] For each preset polarization mode, the initial shielding coefficient of the system under test under the preset polarization mode is obtained based on the ratio between the maximum electric field intensity and the reference electric field intensity among all the received electric field intensities.

[0020] For all initial shielding coefficients of the system under test under various preset polarization modes, the minimum shielding coefficient among all initial shielding coefficients is determined as the target shielding coefficient.

[0021] In one embodiment, the method further includes:

[0022] For electromagnetic waves of a preset intensity emitted by the transmitting antenna, obtain the preset transmission frequency of the electromagnetic waves;

[0023] When the preset transmission frequency is within the first frequency range, the type of transmission antenna is determined to be a log-periodic antenna;

[0024] When the preset transmission frequency is within the second frequency range, the type of transmitting antenna is determined to be a horn antenna; wherein the lower limit of the second frequency range is not less than the upper limit of the first frequency range.

[0025] Secondly, this application also provides a low-level sweep field test apparatus, the apparatus comprising:

[0026] The first acquisition module is used to acquire, under the condition that the positional relationship between the transmitting antenna located outside the system under test and the receiving antenna located inside the system under test satisfies the preset positional relationship, multiple preset polarization modes, multiple preset illumination angles, and the corresponding reference electric field strength of each preset polarization mode; wherein, the polarization mode is used to determine the vector direction of the electric field in the electromagnetic wave emitted by the transmitting antenna, and the illumination angle is used to determine the propagation direction of the electromagnetic wave emitted by the transmitting antenna.

[0027] The second acquisition module is used to acquire the received electric field strength of the electric field in the first electromagnetic wave received by the receiving antenna when the transmitting antenna transmits electromagnetic waves of a preset intensity based on the preset combination formed by different preset polarization methods and different preset illumination angles, and to determine the received electric field strength as the corresponding received electric field strength of the preset combination.

[0028] The determination module is used to determine the target shielding coefficient of the system under test based on the received electric field strength corresponding to the preset combination of preset polarization mode and the reference electric field strength corresponding to the preset polarization mode; wherein, the shielding coefficient characterizes the shielding capability of the system under test against external electric fields.

[0029] Thirdly, this application also provides a computer device. The computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the steps of the method in any of the above embodiments.

[0030] Fourthly, this application also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program thereon, which, when executed by a processor, implements the steps of the methods in any of the above embodiments.

[0031] Fifthly, this application also provides a computer program product. The computer program product includes a computer program that, when executed by a processor, implements the steps of the methods in any of the above embodiments.

[0032] The aforementioned low-level swept field test method, apparatus, computer equipment, computer-readable storage medium, and computer program product, under the condition that the positional relationship between the transmitting antenna located outside the system under test and the receiving antenna located inside the system under test satisfies a preset positional relationship, acquires multiple preset polarization modes, multiple preset illumination angles of the transmitting antenna, and the corresponding reference electric field strength for each preset polarization mode; wherein, the polarization mode is used to determine the vector direction of the electric field in the electromagnetic wave emitted by the transmitting antenna, and the illumination angle is used to determine the propagation direction of the electromagnetic wave emitted by the transmitting antenna; for preset combinations formed by different preset polarization modes and different preset illumination angles, when the transmitting antenna emits an electromagnetic wave of preset intensity based on the preset combination, the received electric field strength of the electric field in the first electromagnetic wave received by the receiving antenna is acquired, and the received electric field strength is determined as the received electric field strength corresponding to the preset combination; based on the received electric field strength corresponding to the preset combination of the preset polarization mode and the corresponding reference electric field strength of the preset polarization mode, the target shielding coefficient of the system under test is determined; wherein, the shielding coefficient characterizes the shielding capability of the system under test against external electric fields. The method provided in this application can directly determine the shielding coefficient of the entire system. The shielding coefficient determined in this way is more in line with the actual shielding capability of the system. Furthermore, the shielding coefficient is determined comprehensively based on different preset polarization methods and different preset illumination angles, making the determined shielding coefficient more accurate. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a flowchart illustrating a low-level swept field test method in one embodiment;

[0035] Figure 2 Here is a block diagram of the test system in one embodiment;

[0036] Figure 3 This is a flowchart illustrating a method for determining the reference electric field strength in one embodiment;

[0037] Figure 4 This is a block diagram of another test system in one embodiment;

[0038] Figure 5 This is a schematic diagram of the electromagnetic waves received by the receiving antenna in one embodiment;

[0039] Figure 6 This is a schematic diagram of direct and reflected waves in one embodiment;

[0040] Figure 7 This is a schematic diagram of electromagnetic waves received by another receiving antenna in one embodiment;

[0041] Figure 8 This is a flowchart illustrating a low-level swept field test method in another embodiment;

[0042] Figure 9 This is a structural block diagram of a low-level swept field test apparatus in one embodiment;

[0043] Figure 10 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0045] In existing technologies, the reverberation chamber method is often used for high-intensity radiation field testing. However, since the reverberation chamber method requires a relatively small space, it can only be used to test equipment within an aircraft, and not to test the entire aircraft system.

[0046] The method provided in this embodiment can directly determine the shielding coefficient of the entire aircraft system. The shielding coefficient determined in this way is more in line with the actual shielding capability of the aircraft system. Furthermore, the shielding coefficient is determined comprehensively based on different preset polarization methods and different preset illumination angles, making the determined shielding coefficient more accurate.

[0047] In one embodiment, such as Figure 1 As shown, a low-level swept field test method is provided. This embodiment illustrates the method by applying it to a terminal. It is understood that this method can also be applied to a server, and to a system including both a terminal and a server, and implemented through interaction between the terminal and the server. In this embodiment, the method includes the following steps:

[0048] S102. Given the positional relationship between the transmitting antenna located outside the system under test and the receiving antenna located inside the system under test, and provided that the preset positional relationship is satisfied, obtain multiple preset polarization modes, multiple preset illumination angles, and the corresponding reference electric field strength for each preset polarization mode; wherein, the polarization mode is used to determine the vector direction of the electric field in the electromagnetic wave emitted by the transmitting antenna, and the illumination angle is used to determine the propagation direction of the electromagnetic wave emitted by the transmitting antenna.

[0049] A transmitting antenna is a device that converts electrical signals into electromagnetic waves and radiates them into free space. A receiving antenna is a device that converts electromagnetic waves in space into electrical signals. Polarization can be represented by the angle between the transmitting antenna and the ground. The angle between the vector direction of the electric field and the ground is the same as the angle between the transmitting antenna and the ground. Polarization can include, but is not limited to, horizontal polarization, vertical polarization, and linear polarization. Horizontal polarization means that the vector direction of the electric field is parallel to the ground (the angle between the vector direction and the ground is 0°), vertical polarization means that the vector direction of the electric field is perpendicular to the ground (the angle between the vector direction and the ground is 90°), and linear polarization means that the angle between the vector direction of the electric field and the ground is any angle between 0° and 90°. The illumination angle represents the main direction or the width of the main lobe of the electromagnetic wave emitted by the transmitting antenna, which is used to describe the degree of concentration of the radiated energy of the transmitting antenna in space.

[0050] Optionally, when the system under test is an aircraft, the connection diagram of the test system can be as follows: Figure 2 As shown, the frequency coverage range of the test system can be, but is not limited to, 100MHz~18GHz. Figure 2In this system, the signal analyzer has radio frequency (RF) signal transmission and reception capabilities, used to output and receive sinusoidal signals. It can achieve RF signal sweep output and reception, and also has signal analysis windowing, time-domain pattern measurement, and time-domain gating functions. For example, the signal analyzer can be a vector network analyzer. The power amplifier amplifies the signal output from the signal analyzer. Its input is connected to the signal analyzer, and its output is connected to the transmitting antenna to drive the transmitting antenna to generate an electric field. In HIRF testing, a power amplifier with multiple frequency bands is usually required. The stirrer is located inside the cabin and near the receiving antenna. During the test, the stirrer rotates to agitate the electric field inside the cabin, ensuring that the electric field is uniform. The fiber optic transmission system includes a transmitting module and a receiving module. The system consists of a transmitter module whose input is a radio frequency signal connected to a receiving antenna, and an output of an optical signal connected to the input of a receiver module via optical fiber. The receiver module converts the optical signal into an electrical signal and outputs the electrical signal to the input of a signal analyzer. The optical fiber transmission system has built-in attenuators and amplifiers to attenuate or amplify the input signal. The control computer controls the signal analyzer and the optical fiber transmission system through installed test software. Specifically, the test software can control the signal analyzer's frequency selection, frequency sweeping output, and reception process. It can automatically adjust the attenuation or gain of the optical fiber transmission system according to the test signal strength, automatically compensate for attenuation according to transmission link loss, calculate the test time per frequency point based on the stirrer speed, and perform data processing and analysis based on the test results to generate a transfer function.

[0051] S104. For preset combinations formed by different preset polarization methods and different preset illumination angles, when the transmitting antenna transmits electromagnetic waves of preset intensity based on the preset combination, the received electric field intensity of the electric field in the first electromagnetic wave received by the receiving antenna is obtained, and the received electric field intensity is determined as the corresponding received electric field intensity of the preset combination.

[0052] Optionally, since the electric field has directionality, the received electric field strength can be the combined electric field strength of the electric field in the first electromagnetic wave in the X, Y, and Z directions, where the plane formed by the X and Y directions is parallel to the ground, and the X and Y directions are perpendicular to each other, and the Z direction is perpendicular to the ground; the received electric field strength can be expressed as follows:

[0053]

[0054] In the formula, To receive electric field strength, Let X be the electric field intensity in the X direction. Let Y be the electric field intensity in the Y direction. Let be the electric field intensity in the Z direction.

[0055] Optionally, due to reflections within the system under test and the presence of a stirrer, electromagnetic waves will undergo multiple reflections after irradiating the system. The electric field measured after these multiple reflections is a reverberant environmental electric field. Therefore, the received electric field strength is theoretically a statistically uniform value, meaning the electric field strength is the same in the X, Y, and Z directions. For example, when the preset polarization is horizontal or vertical, the received electric field strength can be expressed as follows:

[0056]

[0057]

[0058] In the formula, and These represent the received electric field strength for horizontal polarization and the received electric field strength for vertical polarization, respectively. Let be the electric field intensity in any one of the X, Y, and Z directions under horizontal polarization. Let be the electric field intensity in any one of the three directions X, Y, and Z under vertical polarization.

[0059] S106. Based on the received electric field strength corresponding to the preset combination of the preset polarization mode and the reference electric field strength corresponding to the preset polarization mode, determine the target shielding coefficient of the system under test; wherein, the shielding coefficient characterizes the shielding capability of the system under test against external electric fields.

[0060] The larger the shielding coefficient, the stronger the shielding ability of the tested system to external electric fields.

[0061] Optionally, the initial shielding coefficient of the system under test can be determined first under each preset polarization mode. Then, a shielding coefficient can be selected from all the initial shielding coefficients according to the preset selection rules as the target shielding coefficient. Alternatively, all the initial shielding coefficients can be input into a preset function, and the target shielding coefficient can be determined based on the function output. This application embodiment does not specifically limit this.

[0062] In the aforementioned low-level swept field test method, under the condition that the positional relationship between the transmitting antenna located outside the system under test and the receiving antenna located inside the system under test satisfies the preset positional relationship, multiple preset polarization modes, multiple preset illumination angles, and the corresponding reference electric field strength of each preset polarization mode are obtained. The polarization mode is used to determine the vector direction of the electric field in the electromagnetic wave emitted by the transmitting antenna, and the illumination angle is used to determine the propagation direction of the electromagnetic wave emitted by the transmitting antenna. For preset combinations formed by different preset polarization modes and different preset illumination angles, when the transmitting antenna emits an electromagnetic wave of a preset intensity based on the preset combination, the received electric field strength of the first electromagnetic wave received by the receiving antenna is obtained, and the received electric field strength is determined as the received electric field strength corresponding to the preset combination. Based on the received electric field strength corresponding to the preset combination of the preset polarization mode and the corresponding reference electric field strength of the preset polarization mode, the target shielding coefficient of the system under test is determined. The shielding coefficient characterizes the shielding capability of the system under test against external electric fields. The method provided in this application can directly determine the shielding coefficient of the entire system. The shielding coefficient determined in this way is more in line with the actual shielding capability of the system. Furthermore, the shielding coefficient is determined comprehensively based on different preset polarization methods and different preset illumination angles, making the determined shielding coefficient more accurate.

[0063] In some embodiments, the preset positional relationship is that the height of the first preset point on the transmitting antenna relative to the ground is a first preset height, the height of the second preset point on the receiving antenna relative to the ground is a second preset height, the distance between the first preset point and the second preset point is a preset distance, and both the transmitting antenna and the receiving antenna are within a preset test range.

[0064] In some embodiments, such as Figure 3 As shown, the reference electric field intensity for each preset polarization mode is obtained, including:

[0065] S302. Under the condition that the height of the first preset point relative to the ground is the first preset height, the height of the second preset point relative to the ground is the second preset height, the distance between the first preset point and the second preset point is the preset distance, and both the transmitting antenna and the receiving antenna are outside the system under test and are within the preset test range, obtain the reference illumination angle of the transmitting antenna.

[0066] S304. For the reference combination formed by the preset polarization mode and the reference illumination angle, when the transmitting antenna transmits electromagnetic waves of a preset intensity based on the reference combination, the initial frequency domain signal of the second electromagnetic wave received by the receiving antenna is obtained, and the initial frequency domain signal is inversely transformed to obtain multiple consecutive initial time domain signals.

[0067] S306. Obtain a preset time period and determine the signal within the preset time period from multiple consecutive initial time domain signals as the target time domain signal.

[0068] S308. Perform a forward transform on the target time domain signal to obtain the target frequency domain signal, and determine the corresponding electric field strength of the target frequency domain signal as the reference electric field strength corresponding to the preset polarization mode.

[0069] Optionally, but not limited to, the initial frequency domain signal can be inversely transformed based on the inverse fast Fourier transform (IFFT) or the inverse linear frequency modulated Z transform (ICZT), and the target time domain signal can be forward transformed based on the fast Fourier transform (FFT) or the linear frequency modulated Z transform (CZT).

[0070] Optionally, a preset time period can be regarded as a time-domain gate to filter the initial time-domain signals of multiple consecutive frames, retaining the initial time-domain signals within the time-domain gate and eliminating the initial time-domain signals outside the time-domain gate.

[0071] Optionally, the connection diagram of the test system for determining the reference electric field strength can be as follows: Figure 4 As shown, Figure 4 In this system, both the receiving antenna and the transmitting antenna are located outside the system under test.

[0072] In this embodiment, the signal within a preset time period in the multiple consecutive initial time-domain signals is determined as the target time-domain signal. This way, only the time-domain signal related to the determination of the reference electric field strength is retained, and irrelevant time-domain signals are eliminated, making the determined reference electric field strength more accurate.

[0073] In some embodiments, the second electromagnetic wave includes a direct wave and a reflected wave; wherein, the direct wave is an electromagnetic wave directly received by the receiving antenna and emitted by the transmitting antenna, and the reflected wave is an electromagnetic wave reflected outward by a reflecting object based on the received electromagnetic wave emitted by the transmitting antenna; obtaining a preset time period includes: obtaining a first receiving time when the receiving antenna receives the direct wave and a second receiving time when it receives the reflected wave; obtaining the time interval between the first receiving time and the second receiving time, and determining the time period centered on the first receiving time and with the time interval as the duration as the preset time period.

[0074] Optionally, electromagnetic waves may be reflected when they encounter buildings, trees, or other objects during propagation, forming reflected waves. When the reflected wave and the direct wave act on the same point, the superposition of the direct and reflected waves with different phases will affect the electric field strength at that point, resulting in a multipath effect. Therefore, in determining the reference electric field strength, it is necessary to filter out the electric field strength corresponding to the reflected wave from the electric field strength received by the receiving antenna. The target time-domain signal within a preset time period is the remaining time-domain signal after filtering, which is also the time-domain signal corresponding to the direct wave. The reference electric field strength determined based on the target time-domain signal is the electric field strength of the direct wave received by the receiving antenna.

[0075] Optionally, in determining the reference electric field strength, if there are no reflecting objects, the electric field strength received by the receiving antenna is only related to the gain and spatial attenuation of the transmitting and receiving antennas. If the preset test area is completely covered with absorbing material, it can be assumed that there are no reflecting objects within the preset test area. For example... Figure 5 As shown, Figure 5 The more tortuous curve represents the change in electromagnetic waves received by the receiving antenna when no absorbing material is laid within the preset test range, while the smoother curve represents the change in electromagnetic waves received by the receiving antenna when the preset test range is fully covered with absorbing material. As can be seen from the figure, the presence of reflective objects has a greater impact on the electromagnetic waves received by the receiving antenna.

[0076] Optionally, since direct and reflected waves cannot be directly distinguished in the frequency domain, the frequency domain signal is transformed to the time domain using IFFT or ICZT for display. In the time domain, two prominent signals can be clearly observed: one is the direct wave from the transmitting antenna, and the other is the reflected wave from the electromagnetic wave radiated by the transmitting antenna, which reaches the receiving antenna after being reflected by a reflecting object. Because the direct wave has a shorter propagation path and takes less time than the reflected wave, the first arriving wave crest is displayed as the direct wave in the time domain, and the subsequent arriving wave crests are the reflected waves, such as... As shown, M1 and M2 are the signals corresponding to the direct wave and the reflected wave, respectively, and the time interval between the two signals is the propagation time of the path difference between the direct and reflected waves. By setting an appropriate preset time period (time domain gate), M1 and M2 can be separated, retaining the M1 signal corresponding to the direct wave and eliminating the M2 signal corresponding to the reflected wave, thereby eliminating the multipath effect. Figure 7 As shown, Figure 7The most convoluted curve is the waveform of the electromagnetic wave received by the receiving antenna when neither absorbing material is laid within the preset test range nor time-domain gate processing is performed. Of the two smoother curves, one is the waveform of the electromagnetic wave received by the receiving antenna when absorbing material is laid within the preset test range, and the other is the waveform of the electromagnetic wave received by the receiving antenna after time-domain gate processing. It can be seen from the figure that the waveform after time-domain gate processing is basically consistent with the waveform obtained when absorbing material is laid within the preset test range.

[0077] In this embodiment, by determining the preset time period based on the first receiving time when the receiving antenna receives the direct wave and the second receiving time when it receives the reflected wave, the reflected wave can be eliminated from the electromagnetic waves received by the receiving antenna more accurately, thereby making the subsequently determined reference electric field strength more accurate.

[0078] In some embodiments, determining the target shielding coefficient of the system under test based on the received electric field strength corresponding to the preset combination of preset polarization and the reference electric field strength corresponding to the preset polarization includes: for all received electric field strengths corresponding to each preset combination of preset polarization, obtaining the initial shielding coefficient of the system under test under the preset polarization based on the ratio between the maximum electric field strength and the reference electric field strength among all received electric field strengths; and for all initial shielding coefficients of the system under test under multiple preset polarizations, determining the minimum shielding coefficient among all initial shielding coefficients as the target shielding coefficient.

[0079] Optionally, when multiple preset polarization modes are used, including horizontal polarization and vertical polarization, the formula for determining the target shielding coefficient is as follows:

[0080]

[0081] In the formula, The target shielding coefficient, These represent the received electric field intensities corresponding to preset combinations formed by horizontal polarization and different preset illumination angles. These represent the received electric field intensities corresponding to preset combinations formed by vertical polarization and different preset illumination angles. The reference electric field strength corresponding to horizontal polarization, The reference electric field strength corresponding to vertical polarization, This represents the initial shielding coefficient corresponding to horizontal polarization. This represents the initial shielding coefficient corresponding to vertical polarization.

[0082] In this embodiment, the minimum initial shielding coefficient is determined as the target shielding coefficient. Thus, the shielding capability of the system under test determined based on the target shielding coefficient is the lower limit of the shielding capability of the system under test. Based on this lower limit of shielding capability, the maximum electric field intensity that the system under test is allowed to be irradiated by is determined, which can maximize the safety of the system under test during the process of being irradiated by electromagnetic waves.

[0083] In some embodiments, the method further includes: obtaining a preset transmission frequency of an electromagnetic wave of preset intensity emitted by a transmitting antenna; determining the type of the transmitting antenna as a log-periodic antenna when the preset transmission frequency is within a first frequency range; and determining the type of the transmitting antenna as a horn antenna when the preset transmission frequency is within a second frequency range; wherein the lower limit of the second frequency range is not less than the upper limit of the first frequency range.

[0084] Among them, the log-periodic antenna is a broadband antenna. Its design is based on a log-periodic structure and can maintain good performance over a wide frequency range. This antenna consists of a series of gradually changing dipoles, the length and spacing of each dipole changing according to a log-periodic law. The horn antenna is a waveguide antenna, one end of which gradually expands into a horn shape. It is used to convert electromagnetic waves in the waveguide into electromagnetic waves in free space. Horn antennas are usually used in the microwave band and have high gain and good directivity.

[0085] Optionally, when the first frequency range is 100MHz to 1GHz, the type of transmitting antenna is determined to be a log-periodic antenna; when the first frequency range is 1GHz to 18GHz, the type of transmitting antenna is determined to be a horn antenna.

[0086] In this embodiment, different types of transmitting antennas are selected for different transmitting frequencies, which can improve the propagation efficiency of electromagnetic waves and optimize the coverage of electromagnetic waves.

[0087] In one embodiment, such as Figure 8 As shown, another low-level swept field test method is provided, which includes the following:

[0088] (1) Electric field calibration

[0089] a) Select the test location, determine the test area, and follow the instructions. Figure 4 Connect to the test system.

[0090] b) Determine the height and distance of the transmitting and receiving antennas. The height of the transmitting and receiving antennas depends on the height of the electric field measurement position inside the aircraft. There are no special requirements for the distance. Just make sure that the measurement position can be covered by the main lobe width of the transmitting antenna and that the electric field signal can be measured inside the aircraft. Usually, a test distance of 10m is selected.

[0091] c) First, perform pre-calibration to obtain information on direct and reflected waves. Set a fixed output power in the signal analyzer, turn on the power amplifier to perform a frequency sweep test, obtain the spectrum curve, switch to time domain mode, find the direct and reflected waves (in time domain mode, the first arriving peak is the direct wave, and the subsequent arriving peaks are the reflected waves), and mark the arrival time t0 of the direct wave and the arrival time t1 of the first reflected wave.

[0092] d) The test software sets the signal analyzer's test frequency range and a fixed output power P0. At the same time, the time domain gate parameters are set to center time t0 and gate width t1-t0. The time domain gate is opened, and a frequency sweep test is performed to obtain the electric field intensity spectrum curve after the time domain gate is opened.

[0093] e) Obtain the horizontal polarization calibration electric field strength E0 in this manner. H and the calibrated electric field strength E of vertical polarization 0-V .

[0094] (2) Measurement of electric field inside the aircraft

[0095] a) Move the aircraft to the test area, and follow... Figure 2 Connect to the test system.

[0096] b) Place the receiving antenna at the location to be measured. The polarization of the receiving antenna is between horizontal and vertical polarization, and it is placed at 45° (theoretically, polarization does not need to be considered in a reverberant environment, but in actual testing, in order to avoid antenna polarization isolation, the receiving antenna is placed at 45°).

[0097] c) The stirrer is placed near the receiving antenna and the rotation speed is set to v, in revolutions per second (r / s).

[0098] d) Set the signal analyzer's test frequency range and the fixed output power P0 set during calibration in the test software, and set the dwell time per frequency point. The maximum value of the trajectory mode is maintained for seconds, without the need to open the time domain gate, and the maximum internal electric field strength value is obtained by frequency sweep test.

[0099] e) Switch the polarization of the transmitting antenna while keeping the receiving antenna unchanged, and obtain the internal electric field strength E of the aircraft under the two polarization test conditions at the current illumination angle. H1 and E V1 .

[0100] f) By changing different illumination angles, obtain the internal electric field strength E of the aircraft under two polarization test conditions at n illumination angles. Hn and E Vn .

[0101] (3) Data processing

[0102] Since electric fields have directionality, the electric field strength at a certain location should be the combined electric field strength in the X, Y, and Z directions at that location. The combined electric field strength inside the aircraft is calculated using the following formula:

[0103]

[0104] Due to reflections from the aircraft's internal cavities and the presence of agitators, the electric field measured after electromagnetic waves irradiate the aircraft's interior and undergo multiple reflections is a reverberant environmental electric field. Theoretically, it is a statistically uniform value, with the electric field strength being the same in every direction. In actual testing, only one set of electric field values ​​E was measured for each polarization of the transmitting antenna. H and E V This is equivalent to an electric field value in only one direction, which needs to be multiplied by... ,Right now and Only then can the combined electric field inside the aircraft be represented. Under horizontally and vertically polarized illumination, the combined internal electric field strength is expressed as:

[0105]

[0106]

[0107] For each polarization irradiation, electric field intensity test data are obtained from multiple angles. The largest value at each frequency is used to form an envelope curve, which is then normalized to the calibration electric field of the corresponding polarization to obtain the aircraft shielding attenuation under a single polarization. The shielding attenuation under two polarizations is then compared, and the smallest envelope, corresponding to the worst aircraft shielding effectiveness, is selected. This yields a set of shielding attenuation data. The same data processing is performed on each test location, resulting in a shielding attenuation function for each location. The calculation method for aircraft shielding attenuation is as follows:

[0108]

[0109] In the formula Let be the electric field strength inside the aircraft under horizontally polarized n illumination angles. Let E be the electric field strength inside the aircraft under vertically polarized n illumination angles. 0-H and E 0-V These are the electric field calibration intensities for horizontal and vertical polarization, respectively.

[0110] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0111] Based on the same inventive concept, this application also provides a low-level sweep field test apparatus for implementing the low-level sweep field test method described above. The solution provided by this apparatus is similar to the implementation described in the above method; therefore, the specific limitations in one or more embodiments of the low-level sweep field test apparatus provided below can be found in the limitations of the low-level sweep field test method described above, and will not be repeated here.

[0112] In one exemplary embodiment, such as Figure 9 As shown, a low-level swept field test apparatus 900 is provided, comprising: a first acquisition module 901, a second acquisition module 902, and a determination module 903, wherein:

[0113] The first acquisition module 901 is used to acquire, under the condition that the positional relationship between the transmitting antenna located outside the system under test and the receiving antenna located inside the system under test satisfies the preset positional relationship, multiple preset polarization modes, multiple preset illumination angles, and the corresponding reference electric field strength of each preset polarization mode; wherein, the polarization mode is used to determine the vector direction of the electric field in the electromagnetic wave emitted by the transmitting antenna, and the illumination angle is used to determine the propagation direction of the electromagnetic wave emitted by the transmitting antenna.

[0114] The second acquisition module 902 is used to acquire the received electric field strength of the electric field in the first electromagnetic wave received by the receiving antenna when the transmitting antenna transmits electromagnetic waves of a preset intensity based on the preset combination formed by different preset polarization methods and different preset illumination angles, and to determine the received electric field strength as the corresponding received electric field strength of the preset combination.

[0115] The determination module 903 is used to determine the target shielding coefficient of the system under test based on the received electric field strength corresponding to the preset combination of preset polarization mode and the reference electric field strength corresponding to the preset polarization mode; wherein, the shielding coefficient characterizes the shielding capability of the system under test against external electric fields.

[0116] In some embodiments, the low-level sweep field test apparatus 900 is specifically used to preset the positional relationship as follows: the height of a first preset point on the transmitting antenna relative to the ground is a first preset height, the height of a second preset point on the receiving antenna relative to the ground is a second preset height, the distance between the first preset point and the second preset point is a preset distance, and both the transmitting antenna and the receiving antenna are within a preset test range.

[0117] In some embodiments, the first acquisition module 901 includes:

[0118] The first acquisition unit is used to acquire the reference illumination angle of the transmitting antenna when the height of the first preset point relative to the ground is a first preset height, the height of the second preset point relative to the ground is a second preset height, the distance between the first preset point and the second preset point is a preset distance, and both the transmitting antenna and the receiving antenna are outside the system under test and within a preset test range.

[0119] The second acquisition unit is used to acquire the initial frequency domain signal of the second electromagnetic wave received by the receiving antenna when the transmitting antenna transmits electromagnetic waves of a preset intensity based on the reference combination formed by the preset polarization mode and the reference illumination angle, and to perform inverse transformation on the initial frequency domain signal to obtain multiple consecutive initial time domain signals.

[0120] The third acquisition unit is used to acquire a preset time period and determine the signal within the preset time period from multiple consecutive initial time-domain signals as the target time-domain signal.

[0121] The transformation unit is used to perform a forward transformation on the target time-domain signal to obtain the target frequency-domain signal, and to determine the electric field intensity of the target frequency-domain signal as the reference electric field intensity corresponding to the preset polarization mode.

[0122] In some embodiments, the second electromagnetic wave includes a direct wave and a reflected wave; wherein, the direct wave is an electromagnetic wave directly received by the receiving antenna and emitted by the transmitting antenna, and the reflected wave is an electromagnetic wave reflected outward by a reflecting object based on the received electromagnetic wave emitted by the transmitting antenna; the third acquisition unit is further configured to acquire a first reception time when the receiving antenna receives the direct wave and a second reception time when it receives the reflected wave; acquire the time interval between the first reception time and the second reception time, and determine the time interval centered on the first reception time and with the time interval as the duration as a preset time interval.

[0123] In some embodiments, the determining module 903 is further configured to, for all received electric field intensities corresponding to each preset polarization mode, obtain the initial shielding coefficient of the system under test under the preset polarization mode based on the ratio between the maximum electric field intensity and the reference electric field intensity among all received electric field intensities; and for all initial shielding coefficients of the system under test under multiple preset polarization modes, determine the minimum shielding coefficient among all initial shielding coefficients as the target shielding coefficient.

[0124] In some embodiments, the low-level swept field test apparatus 900 is further configured to obtain a preset transmission frequency of an electromagnetic wave of preset intensity emitted by a transmitting antenna; when the preset transmission frequency is within a first frequency range, determine the type of the transmitting antenna as a log-periodic antenna; when the preset transmission frequency is within a second frequency range, determine the type of the transmitting antenna as a horn antenna; wherein the lower limit of the second frequency range is not less than the upper limit of the first frequency range.

[0125] Each module in the aforementioned low-level swept field test apparatus can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0126] In one exemplary embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram may be as follows: Figure 10 As shown, the computer device includes a processor, memory, input / output interface, communication interface, display unit, and input device. The processor, memory, and input / output interface are connected via a system bus, and the communication interface, display unit, and input device are also connected to the system bus via the input / output interface. The processor provides computational and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage medium. The input / output interface is used for exchanging information between the processor and external devices. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, mobile cellular networks, Near Field Communication (NFC), or other technologies. When executed by the processor, the computer program implements a low-level swept-field testing method.

[0127] Those skilled in the art will understand that Figure 10The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0128] In one embodiment, a computer device is also provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above method embodiments.

[0129] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon that, when executed by a processor, implements the steps in the above method embodiments.

[0130] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0131] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0132] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.

[0133] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0134] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A low-level swept field test method, characterized by, The method comprises: In a positional relationship between a transmitting antenna located outside a measured system and a receiving antenna located inside the measured system, in a case where a preset positional relationship is met, a plurality of preset polarization modes of the transmitting antenna, a plurality of preset irradiation angles, and a reference electric field intensity corresponding to each preset polarization mode are acquired; wherein the polarization mode is used to determine the vector direction of the electric field in the electromagnetic wave emitted by the transmitting antenna, and the irradiation angle is used to determine the propagation direction of the electromagnetic wave emitted by the transmitting antenna; the preset positional relationship is that a first preset point on the transmitting antenna has a first preset height relative to the ground, a second preset point on the receiving antenna has a second preset height relative to the ground, the distance between the first preset point and the second preset point is a preset distance, and the transmitting antenna and the receiving antenna are both within a preset test range; The acquisition method of the reference electric field intensity corresponding to each preset polarization mode comprises: acquiring a reference irradiation angle of the transmitting antenna in a case where the first preset point has the first preset height relative to the ground, the second preset point has the second preset height relative to the ground, the distance between the first preset point and the second preset point is the preset distance, the transmitting antenna and the receiving antenna are both outside the measured system, and are both within the preset test range; for a reference combination formed by the preset polarization mode and the reference irradiation angle, in a case where the transmitting antenna emits electromagnetic waves of the preset intensity based on the reference combination, an initial frequency domain signal of the second electromagnetic wave received by the receiving antenna is acquired, and an inverse transform is performed on the initial frequency domain signal to obtain a plurality of frames of continuous initial time domain signals; a preset time period is acquired, and a signal within the preset time period in the plurality of frames of continuous initial time domain signals is determined as a target time domain signal; a forward transform is performed on the target time domain signal to obtain a target frequency domain signal, and a corresponding electric field intensity of the target frequency domain signal is determined as the reference electric field intensity corresponding to the preset polarization mode; For a preset combination formed by different preset polarization modes and different preset irradiation angles, in a case where the transmitting antenna emits electromagnetic waves of a preset intensity based on the preset combination, a receiving electric field intensity of the electric field in the first electromagnetic wave received by the receiving antenna is acquired, and the receiving electric field intensity is determined as the receiving electric field intensity corresponding to the preset combination; Based on the receiving electric field intensity corresponding to the preset combination in which the preset polarization mode is located, and the reference electric field intensity corresponding to the preset polarization mode, a target shielding coefficient of the measured system is determined; wherein the shielding coefficient represents the shielding ability of the measured system to external electric fields.

2. The method of claim 1, wherein, The second electromagnetic wave comprises direct waves and reflected waves; wherein the direct waves are electromagnetic waves emitted by the transmitting antenna and directly received by the receiving antenna, and the reflected waves are electromagnetic waves reflected outward by a reflecting object based on the received electromagnetic waves emitted by the transmitting antenna; the acquisition of the preset time period comprises: acquire a first receiving moment when the direct wave is received by the receiving antenna and a second receiving moment when the reflected wave is received; acquire a time interval between the first receiving moment and the second receiving moment, and determine a time period with the first receiving moment as a center moment and with the time interval as a time length as the preset time period.

3. The method of claim 1, wherein, The target shielding coefficient of the measured system is determined based on the received electric field intensity corresponding to the preset combination of the preset polarization mode and the reference electric field intensity corresponding to the preset polarization mode, and includes: For all received electric field intensities corresponding to each preset combination of the preset polarization mode, an initial shielding coefficient of the measured system under the preset polarization mode is acquired based on a ratio between the maximum electric field intensity in the all received electric field intensities and the reference electric field intensity; For all initial shielding coefficients of the measured system under the multiple preset polarization modes, the minimum shielding coefficient in the all initial shielding coefficients is determined as the target shielding coefficient.

4. The method of claim 1, wherein, The method further includes: For the electromagnetic wave of the preset intensity emitted by the transmitting antenna, a preset transmitting frequency of the electromagnetic wave is acquired; In a case where the preset transmitting frequency is within a first frequency range, the type of the transmitting antenna is determined as a logarithmic-periodic antenna; In a case where the preset transmitting frequency is within a second frequency range, the type of the transmitting antenna is determined as a horn antenna; wherein a lower limit value of the second frequency range is not less than an upper limit value of the first frequency range.

5. A low-level swept field test apparatus, characterized by, The device includes: The first acquiring module is configured to, in a case where a positional relationship between a transmitting antenna located outside a measured system and a receiving antenna located inside the measured system satisfies a preset positional relationship, acquire multiple preset polarization modes, multiple preset illumination angles of the transmitting antenna, and a reference electric field intensity corresponding to each preset polarization mode; wherein a polarization mode is used to determine a vector direction of an electric field in an electromagnetic wave emitted by the transmitting antenna, and an illumination angle is used to determine a propagation direction of the electromagnetic wave emitted by the transmitting antenna; the preset positional relationship is that a first preset point on the transmitting antenna has a first preset height relative to a ground, a second preset point on the receiving antenna has a second preset height relative to the ground, a distance between the first preset point and the second preset point is a preset distance, and the transmitting antenna and the receiving antenna are both within a preset test range; The first acquisition module is further configured to acquire a reference irradiation angle of the transmitting antenna when the first preset point is at the first preset height, the second preset point is at the second preset height, the distance between the first preset point and the second preset point is the preset distance, the transmitting antenna and the receiving antenna are both outside the system under test, and both are within the preset test range; acquire an initial frequency domain signal of a second electromagnetic wave received by the receiving antenna when the transmitting antenna transmits the preset intensity of electromagnetic wave based on a reference combination formed by the preset polarization mode and the reference irradiation angle, and perform inverse transformation on the initial frequency domain signal to obtain a plurality of frames of continuous initial time domain signals; acquire a preset time period, and determine a signal within the preset time period in the plurality of frames of continuous initial time domain signals as a target time domain signal; perform forward transformation on the target time domain signal to obtain a target frequency domain signal, and determine a corresponding electric field intensity of the target frequency domain signal as a reference electric field intensity corresponding to the preset polarization mode; and determine a target shielding coefficient of the system under test based on the corresponding reference electric field intensity of the preset polarization mode and the corresponding reference electric field intensity of the preset polarization mode. The second acquisition module is configured to acquire a receiving electric field intensity of an electric field in a first electromagnetic wave received by the receiving antenna when the transmitting antenna transmits a preset intensity of electromagnetic wave based on a preset combination formed by different preset polarization modes and different preset irradiation angles, and determine the receiving electric field intensity as a corresponding receiving electric field intensity of the preset combination. The determination module is configured to determine a target shielding coefficient of the system under test based on the corresponding receiving electric field intensity of the preset combination in which the preset polarization mode is located and the corresponding reference electric field intensity of the preset polarization mode. The shielding coefficient represents the shielding ability of the system under test to external electric field. 6.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 1-5 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 4.

7. 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 4.

8. A computer program product comprising 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 4. The computer program is executed by the processor to implement the steps of the method of any one of claims 1 to 4.

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