Target Scattering Characteristic Testing System and Testing Method

Abstract

The present invention provides a target scattering characteristic testing system and a testing method. The system includes: a transceiver unit for generating a test signal and receiving an echo signal; a testing unit communicatively connected to the transceiver unit. The testing unit includes a control component and an antenna array. A plurality of transmitting antennas and a plurality of receiving antennas are arranged on the antenna array. The control component is used to control the opening and closing of each of the transmitting antennas and each of the receiving antennas. The transmitting antennas and the receiving antennas are used to test the scattering characteristics of the target; a rotating unit connected to the antenna array for adjusting the angle of the antenna array; a computer communicatively connected to the transceiver unit and the testing unit respectively for controlling the transceiver unit and the testing unit. With this solution, the scattering characteristics of the target at different angles can be obtained quickly.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of electromagnetic scattering, and particularly to a target scattering characteristic test system and a test method. Background Art

[0002] The target scattering characteristic test technology is a powerful tool for diagnosing and analyzing the scattering mechanism of complex targets and supporting the research and development of stealth devices. In the prior art, it is already possible to test the scattering characteristics of a target in three dimensions of range, azimuth, and altitude. However, the existing test system cannot quickly adjust the positions of the transmitting antenna and the receiving antenna. Therefore, when it is necessary to test the scattering characteristics of a target at different angles, the test speed is relatively slow.

[0003] Therefore, there is an urgent need for a target scattering characteristic test system and a test method to quickly obtain the scattering characteristics of a target at different angles. Summary of the Invention

[0004] The embodiments of the present invention provide a target scattering characteristic test system and a test method, which can quickly obtain the scattering characteristics of a target at different angles.

[0005] In a first aspect, the embodiments of the present invention provide a target scattering characteristic test system, including:

[0006] A transceiver unit, configured to generate a test signal and receive an echo signal;

[0007] A test unit, communicatively connected to the transceiver unit. The test unit includes a control component and an antenna array. A plurality of transmitting antennas and a plurality of receiving antennas are arranged on the antenna array. The control component is configured to control the opening and closing of each of the transmitting antennas and each of the receiving antennas. The transmitting antennas and the receiving antennas are configured to test the scattering characteristics of a target;

[0008] A rotation unit, connected to the antenna array, configured to adjust the angle of the antenna array;

[0009] A computer, communicatively connected to the transceiver unit and the test unit respectively, configured to control the transceiver unit and the test unit.

[0010] In a possible design, it further includes a support member, configured to support the antenna array and the rotation unit.

[0011] In a possible design, the central height of the antenna array is the same as the height of the geometric center of the target.

[0012] In a possible design, the antenna array is a linear array.

[0013] In a possible design, the rotation unit is a ratchet structure.

[0014] In a possible design, the transceiver unit includes a radar transmitter, a radar receiver, a power amplifier, a low-noise amplifier, and a filter.

[0015] In a second aspect, an embodiment of the present invention further provides a method for testing the target scattering characteristics, which is applied to the target scattering characteristics testing system in any of the above designs, and the method includes:

[0016] Using the computer to control the transceiver unit to generate a test signal with a preset bandwidth;

[0017] Using the rotation unit to adjust the angle of the antenna array, and at each of the angles, the following operations are performed:

[0018] Using the control component to control the opening and closing of each transmitting antenna and each receiving antenna to obtain a plurality of test channels;

[0019] At each of the test channels, perform scattering characteristic testing on the target to obtain a test result.

[0020] In a possible design, before performing the scattering characteristic testing on the target, it further includes:

[0021] Preheat the transceiver unit to make the transceiver unit reach a stable state.

[0022] In a possible design, after the transceiver unit reaches a stable state, it further includes:

[0023] Perform calibration testing on the target scattering characteristics testing system to remove system errors.

[0024] In a possible design, after performing the scattering characteristic testing on the target to obtain a test result, it further includes:

[0025] Using the computer to process the test result to obtain the distribution function of each scattering center of the target;

[0026] According to the distribution function of each scattering center, obtain a three-dimensional image of the target.

[0027] An embodiment of the present invention provides a target scattering characteristic test system and a test method. The test system includes a transceiver unit, a test unit, a rotation unit, and a computer. Among them, the test unit includes a control component and an antenna array. A plurality of transmitting antennas and a plurality of receiving antennas are arranged on the antenna array. The plurality of transmitting antennas and the plurality of receiving antennas are used to form a plurality of test channels, and each test channel corresponds to a different test angle. In this system, the angle of the antenna array can be adjusted by the rotation unit. At any angle, the control component controls the opening and closing of each transmitting antenna and each receiving antenna to select different test channels. In this way, at any angle, only by selecting the transmitting antenna and the receiving antenna for each test through the control component, the tests of all test channels can be completed, and the scattering characteristics of the target at different test angles can be obtained, without the need to frequently move the positions of the transmitting antenna and the receiving antenna. Therefore, this measurement system can quickly obtain the scattering characteristics of the target at different angles. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0029] Figure 1 It is a schematic diagram of a target scattering characteristic test system provided by an embodiment of the present invention;

[0030] Figure 2 It is a schematic diagram of an antenna array with a transceiver-receiver structure provided by an embodiment of the present invention;

[0031] Figure 3 It is a flowchart of a target scattering characteristic test method provided by an embodiment of the present invention;

[0032] Figure 4 It is a schematic diagram of the antenna array rotating twice provided by an embodiment of the present invention;

[0033] Figure 5 It is a schematic diagram of the antenna array rotating four times provided by an embodiment of the present invention;

[0034] Figure 6 It is a schematic diagram of the antenna array rotating eight times provided by an embodiment of the present invention.

[0035] REFERENCE SIGNS:

[0036] 1 - Transceiver unit;

[0037] 2 - Test unit;

[0038] 21 - Antenna array;

[0039] 3 - Rotating unit;

[0040] 4 - Computer;

[0041] 5 - Support;

[0042] 51 - Support base;

[0043] 52 - Support rod. Detailed implementation manners

[0044] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0045] As described above, the prior art cannot quickly adjust the positions of the transmitting antenna and the receiving antenna. Therefore, when testing the scattering characteristics of a target at different angles, the testing speed is relatively slow.

[0046] To address this problem, the inventor proposes that a control component and a rotating unit can be used to quickly adjust the testing angles of the transmitting antenna and the receiving antenna.

[0047] The following describes the specific implementation manners of the above concept.

[0048] Please refer to Figure 1 , an embodiment of the present invention provides a target scattering characteristic testing system, and the testing system includes:

[0049] A transceiver unit 1 for generating a testing signal and receiving an echo signal;

[0050] A testing unit 2 communicatively connected to the transceiver unit 1. The testing unit 2 includes a control component and an antenna array 21. A plurality of transmitting antennas and a plurality of receiving antennas are arranged on the antenna array 21. The control component is used to control the opening and closing of each transmitting antenna and each receiving antenna, and the transmitting antennas and the receiving antennas are used to test the scattering characteristics of the target;

[0051] A rotating unit 3 connected to the antenna array 21 for adjusting the angle of the antenna array 21;

[0052] A computer 4 communicatively connected to the transceiver unit 1 and the testing unit 2 respectively for controlling the transceiver unit 1 and the testing unit 2.

[0053] An embodiment of the present invention provides a target scattering characteristic test system, which includes a transceiver unit 1, a test unit 2, a rotation unit 3, and a computer 4. Among them, the test unit 2 includes a control component and an antenna array 21. A plurality of transmitting antennas and a plurality of receiving antennas are arranged on the antenna array 21. The plurality of transmitting antennas and the plurality of receiving antennas are used to form a number of test channels, and each test channel corresponds to a different test angle. In this system, the angle of the antenna array 21 can be adjusted by the rotation unit 3. At any angle, the control component controls the opening and closing of each transmitting antenna and each receiving antenna to select different test channels. In this way, at any angle, only by selecting the transmitting antenna and receiving antenna for each test through the control component, the tests of all test channels can be completed, and the scattering characteristics of the target at different test angles can be obtained, without the need to frequently move the positions of the transmitting antenna and the receiving antenna. Therefore, this measurement system can quickly obtain the scattering characteristics of the target at different angles.

[0054] In addition, in this embodiment, the transceiver unit 1 can be a radio frequency transceiver device, which is used to generate a broadband swept-frequency signal, such as a radio frequency signal of 8-12 GHz, to perform a broadband swept-frequency test on the target.

[0055] In some embodiments, the transceiver unit 1 includes a radar transmitter, a radar receiver, a power amplifier, a low-noise amplifier, and a filter. Of course, other devices can also be included. This part belongs to the well-known technology in the art and will not be elaborated here.

[0056] In some embodiments, a support member 5 is further included, which is used to support the antenna array 21 and the rotation unit 3. The support member 5 can include a support base 51 and a support rod 52. The support base 51 is in contact with the ground or the platform. The support rod 52 is arranged on the support base 51 in the vertical direction. The support rod 52 is connected to the rotation unit 3, and the rotation unit 3 is connected to the central position of the antenna array 21.

[0057] In some embodiments, by adjusting the installation height of the rotation unit 3 on the support rod 52, the central height of the antenna array 21 is made the same as the height of the geometric center of the target. Of course, the central height of the antenna array 21 and the height of the geometric center of the target may not be the same. When they are not the same, corresponding phase corrections need to be made to the test results.

[0058] In some embodiments, the antenna array 21 is a linear array, and the control component is a microwave switch matrix. The microwave switch matrix is controlled by the computer 4, so that the microwave switch matrix can switch different transmitting antennas and receiving antennas to test the target, and the antenna array 21 can test the target at different azimuth angles.

[0059] Preferably, the antenna array 21 can adopt, for example Figure 2The transceiver structure shown. Of course, the user can also adopt other multi-input multi-output array configurations, which are not specifically limited in this application.

[0060] In some embodiments, the rotating unit 3 is a ratchet structure, so that the antenna array 21 can be controlled to rotate a fixed angle each time, for example, the rotation angle each time can be 30°, 45°, 60°, etc.

[0061] In a second aspect, as Figure 3 shown, the embodiment of the present invention further provides a method for testing target scattering characteristics, which is applied to the target scattering characteristics testing system in any of the above embodiments. The method includes:

[0062] Step 300: Use the computer 4 to control the transceiver unit 1 to generate a test signal with a preset bandwidth;

[0063] Step 302: Use the rotating unit 3 to adjust the angle of the antenna array 21. At each angle, the following operations are performed:

[0064] Control the opening and closing of each transmitting antenna and each receiving antenna by using the control component to obtain a number of test channels;

[0065] At each test channel, perform a scattering characteristics test on the target to obtain a test result.

[0066] In this embodiment, it is assumed that the antenna array 21 includes 4 transmitting antennas and 5 receiving antennas. Then, according to the principle of permutation and combination, 20 test channels can be formed. Then at each angle, for example, when the angle of the antenna array 21 is 0°, only need to control the microwave switch matrix by the computer 4, select one test channel each time to test the target, obtain the wideband sweep angle result of the target, until the tests of 20 channels are completed, and obtain 20 test results at different angles (i.e., target echo data). After the angle test is completed, the antenna array 21 can be rotated to the next angle by the rotating unit 3, for example, rotated to 90°. At this angle, adopt the above method to complete the tests of 20 channels in sequence until the antenna array 21 is rotated to 180° to complete the test and obtain a preset number of test results.

[0067] Generally speaking, in order to obtain more comprehensive test results, the antenna array 21 needs to be rotated 180°, and the angle interval of each rotation is different, and the number of rotations and the number of tests are also different. As Figure 4 shown, it is a schematic diagram of the antenna array 21 rotating twice, and the rotation angles are 0° and 90°; as Figure 5 shown, it is a schematic diagram of the antenna array 21 rotating four times, and the rotation angles are 0°, 45°, 90°, and 135°; as Figure 6As shown, it is a schematic diagram of the antenna array 21 rotating eight times, with the rotation angles being 0°, 22.5°, 45°, 67.5°, 90°, 112.5°, 135°, and 157.5°. It can be understood that the smaller the rotation angle each time, the more test times, the longer the test time, and the better the corresponding test effect; conversely, the larger the rotation angle each time, the fewer test times, the shorter the test time, and the slightly worse the corresponding test effect. The present application does not make specific limitations on the rotation angle interval.

[0068] In some embodiments, before testing the scattering characteristics of the target, it further includes:

[0069] Preheating the transceiver unit 1 to make the transceiver unit 1 reach a stable state. The preheating time can be 30 minutes. Of course, the specific time depends on the actual situation, and the present application does not make specific limitations.

[0070] Determined according to the actual situation, generally it can be set

[0071] In some embodiments, after the transceiver unit 1 reaches a stable state, it further includes:

[0072] Performing a calibration test on the target scattering characteristic test system to remove system errors.

[0073] In this embodiment, the specific steps of the calibration test are:

[0074] Step A1, placing the calibration sphere at the center position of the antenna array 21, and the center height of the calibration sphere is the same as the center height of the antenna array 21;

[0075] Step A2, determining the test distance R0. The calculation formula for the test distance is:

[0076]

[0077] In the formula, where c is the speed of light, L is the array length, B is the test bandwidth, and λ is the wavelength corresponding to the test center frequency point. The test distance determined by this formula can ensure that the resolution in each dimension of the imaging result is approximately the same.

[0078] Step A3, testing the calibration sphere to obtain the calibration test result of the test system.

[0079] In some embodiments, after testing the scattering characteristics of the target to obtain the test result, it further includes:

[0080] Using the computer 4 to process the test result to obtain the distribution function of each scattering center of the target;

[0081] According to the distribution function of each scattering center, obtain the three-dimensional image of the target.

[0082] In this embodiment, the specific process of obtaining the target three-dimensional image is as follows:

[0083] For the near-field test imaging situation based on the antenna array 21 system, an imaging model is constructed. Let the antenna coordinate system be (u, v), and the target coordinate system be (x, y, z).

[0084] In the case of multiple scattering centers, the echo data received in each test can be expressed as:

[0085]

[0086] In the formula, s(f, u, v) represents the target echo data received under the conditions of the current observation frequency, the current positions of the transmitting antenna and the receiving antenna; Γ(x, y, z) represents the target scattering distribution function of a single scattering center in the target coordinate system; L is the distance in the exponential term, which is the phase delay corresponding to the single scattering center and the reference center, and describes the integral path of the imaging measurement of this scattering center.

[0087] In some embodiments, the geometric relationship of the planar two-dimensional transmit-receive-transmit antenna array 21 is as Figure 2 shown. Under this structure, the calculation formula for the integral path L is:

[0088]

[0089] In the formula, R t is the distance from the transmitting antenna to the scattering center, R0 is the distance from the receiving antenna to the scattering center, and R0 is the distance from the target to the center of the antenna array 21.

[0090] Based on the three-dimensional BP imaging algorithm, perform an inverse transformation on Equation 2 to obtain the following formula:

[0091]

[0092] In the formula, p u,v (L) represents the one-dimensional range image of the test channel, k represents the wave number, k min represents the lower bound of the wave number, k max represents the upper bound of the wave number, e j2πkL represents the phase parameter, u max 、u min respectively represent the upper and lower bounds of one dimension in the antenna coordinate system, v max 、v min respectively represent the upper and lower bounds of another dimension in the antenna coordinate system; is the estimated value of the target scattering distribution function Γ(x, y, z).

[0093] After solving , the three-dimensional image of the target can be obtained.

[0094] Since the above-mentioned target scattering characteristic test method is based on the same concept as the embodiment of the target scattering characteristic test system of the present invention, for the specific content, reference can be made to the description in the embodiment of the positioning system of the present invention, and details are not described herein again.

[0095] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element.

[0096] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A target scattering characteristic test system, characterized in that, Comprising: A transceiver unit (1) for generating a test signal and receiving an echo signal; A test unit (2) communicatively connected to the transceiver unit (1), the test unit (2) includes a control component and an antenna array (21), a plurality of transmitting antennas and a plurality of receiving antennas are provided on the antenna array (21), the control component is used to control the opening and closing of each of the transmitting antennas and each of the receiving antennas, and the transmitting antennas and the receiving antennas are used to test the scattering characteristics of the target; A rotating unit (3) connected to the antenna array (21) for adjusting the angle of the antenna array (21); A computer (4) communicatively connected to the transceiver unit (1) and the test unit (2) respectively for controlling the transceiver unit (1) and the test unit (2); The central height of the antenna array (21) is the same as the height of the geometric center of the target; The computer (4) is used to control the transceiver unit (1) to generate a test signal with a preset bandwidth; The computer (4) is further used to perform: after obtaining the test result, process the test result to obtain the distribution function of each scattering center of the target; and obtain the three-dimensional image of the target according to the distribution function of each scattering center; wherein, The specific process of obtaining the three-dimensional image of the target is: For the near-field test imaging result obtained based on the antenna array, an imaging model is constructed, and the antenna coordinate system is set as (u, v), and the target coordinate system is set as (x, y, z); When there are multiple scattering centers, the echo data received each time the test is performed is expressed as: In the formula, s(f, u, v) represents the target echo data received under the conditions of the current observation frequency, the current positions of the transmitting antenna and the receiving antenna; Γ(x, y, z) represents the target scattering distribution function of a single scattering center in the target coordinate system; L is the distance in the exponential term, which is the phase delay corresponding to the single scattering center and the reference center, describing the integral path of the imaging measurement of this scattering center; the calculation formula of the integral path L is: where R t is the distance from the transmitting antenna to the scattering center, R r is the distance from the receiving antenna to the scattering center, and R0 is the distance from the target to the center of the antenna array; Based on the three-dimensional BP imaging algorithm, perform an inverse transform on s(f, u, v) to obtain the following formula: where p u,v (L) represents the one-dimensional range profile of the test channel, k represents the wave number, k min represents the lower bound of the wave number, k max represents the upper bound of the wave number, e j2πkL represents the phase parameter, u max and u min represent the upper and lower bounds of one dimension in the antenna coordinate system respectively, v max and v min represent the upper and lower bounds of another dimension in the antenna coordinate system respectively; is the estimated value of the target scattering distribution function Γ(x, y, z); After solving the three-dimensional image of the target can be obtained.

2. The test system according to claim 1, characterized in that, It further includes a support member (5) for supporting the antenna array (21) and the rotating unit (3).

3. The test system according to claim 1, wherein The antenna array (21) is a linear array.

4. The test system according to claim 1, characterized in that, The rotating unit (3) is a ratchet structure.

5. The test system according to claim 1, characterized in that, The transceiver unit (1) includes a radar transmitter, a radar receiver, a power amplifier, a low-noise amplifier, and a filter.

6. A method for testing the scattering characteristics of a target, characterized in that, Applied to the target scattering characteristic test system according to any one of claims 1-5, the method includes: Using the computer (4) to control the transceiver unit (1) to generate a test signal with a preset bandwidth; Using the rotating unit (3) to adjust the angle of the antenna array (21), and at each of the angles, perform: Using the control component to control the opening and closing of each of the transmitting antennas and each of the receiving antennas to obtain a number of test channels; At each of the test channels, perform a scattering characteristic test on the target to obtain a test result.

7. The test method according to claim 6, wherein Before performing the scattering characteristic test on the target, it further includes: Preheat the transceiver unit (1) to bring the transceiver unit (1) to a stable state.

8. The test method according to claim 7, wherein After the transceiver unit (1) reaches a stable state, it further includes: Perform a calibration test on the target scattering characteristic test system to remove system errors.

9. The test method according to claim 6, wherein After performing the scattering characteristic test on the target and obtaining the test results, it further includes: Use the computer (4) to process the test results to obtain the distribution function of each scattering center of the target; Obtain the three-dimensional image of the target according to the distribution function of each scattering center.

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