A method for scatter source analysis based on target geometry

Abstract

This invention discloses a scattering source analysis method based on target geometry, comprising the following two steps: First, the scattering center is extracted based on the target's measured data, specifically including: S1, acquiring a two-dimensional radar image; S2, extracting the scattering center; S3, converting the scattering center data to the target's body coordinate system; then, a scattering center distribution model combining the target's geometric characteristics is obtained, specifically including: S4, partitioning the target model; S5, classifying and focusing the scattering centers according to the partitions; S6, obtaining a scattering center distribution model related to the geometric structure. This invention avoids the problem of inaccurate target model description in traditional scattering center extraction methods, and can achieve distributed scattering center modeling that reflects the characteristics of complex target structures, greatly expanding its applicability.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic scattering modeling, and in particular to a scattering source analysis method based on the geometric shape of a target. Background Technology

[0002] From the perspective of target electromagnetic scattering mechanism, the target exhibits an electrically large size relative to the radar's incident wavelength. High-frequency scattering constitutes the main contribution to the target's scattering, resulting in consistent positional attributes at the target's edges, vertices, and geometric discontinuities. This leads to the accumulation of backscattered energy, forming local scattering sources or centers. The target's scattered field is a spatial vector synthesis of the electric fields from multiple scattering centers. Based on the distribution of target scattering centers, complex and time-consuming electromagnetic scattering simulations can be avoided, enabling rapid generation of target echoes. Furthermore, in radar hardware-in-the-loop simulation systems, multiple scattering centers can be used to simulate complex targets, verifying the detection capabilities of the radar under test. When using a scattering center model to simulate and characterize a target in simulation or hardware-in-the-loop testing systems, attention is paid to both the simulation accuracy of the scattering center amplitude on the target's RCS and the simulation of the target's geometric shape based on the scattering center distribution.

[0003] However, although many institutions at home and abroad have conducted relevant research on the scattering center model of targets, covering scattering center analysis based on forward modeling and scattering center analysis based on imaging, further research is still needed on how to comprehensively consider the geometric characteristics and backscattering properties of complex extended targets and realize the descriptive characterization of the distributed scattering center model related to the target geometry.

[0004] Therefore, it is urgent to establish a scattering source analysis method based on the target's geometric shape by analyzing test or simulation data, and to obtain a distributed scattering center model related to the target's geometric structure. This is of great significance for achieving high-precision scattering center characterization and simulation of the target. Summary of the Invention

[0005] The purpose of this invention is to propose a scattering source analysis method based on the target geometry, which can extract a scattering center distribution model that reflects the target's structural scale.

[0006] To achieve the above objectives, this invention provides a scattering source analysis method based on the target's geometric shape, comprising the following two steps: First, the scattering center is extracted based on the target's measured data, specifically including: S1, acquiring a two-dimensional radar image; S2, extracting the scattering center; S3, converting the scattering center data to the target's body coordinate system; then, a scattering center distribution model combining the target's geometric structure characteristics is obtained, specifically including: S4, partitioning the target model; S5, classifying and focusing the scattering centers according to the partitions; S6, obtaining a scattering center distribution model related to the geometric structure.

[0007] Furthermore, step S1 specifically includes:

[0008] S11. Establish a static RCS measurement system with a vector network analyzer as the core in a microwave anechoic chamber. The system mainly includes: radio frequency subsystem, turntable control system and instrument automatic control subsystem. Place the target on the turntable and use the turntable to drive the target to perform azimuth angle scanning, i.e., angle scanning test, to obtain the RCS of the target at each azimuth angle, i.e., the RCS of the angle scanning test.

[0009] S12. While using the turntable to drive the target to carry out the angle sweep test, a frequency sweep test is carried out for each azimuth angle to obtain the RCS of the target at different frequencies in each azimuth angle, that is, the RCS of the frequency sweep test.

[0010] S13. A two-dimensional radar image of the target is obtained by performing Fourier transform on the RCS of the frequency sweep test and the RCS of the angle sweep test.

[0011] Specifically, the calculation method for the RCS of the sweep angle test and the RCS of the sweep frequency test in step S1 is as follows: A standard body under the same test conditions is measured to obtain the maximum value of the standard body's echo power, which is then compared with the echo power of the target to obtain the target's RCS. The calculation formula is: Where, σ s σ is the RCS of the standard body, and U is the RCS of the target. b To measure the output response of the empty chamber receiver, U sm To measure the output response of the standard receiver, U tm To measure the output response of the target receiver.

[0012] The two dimensions of a target's two-dimensional radar image are the radial range dimension and the lateral range dimension. The radial range dimension is related to the sweep frequency parameters, while the lateral range dimension is related to the sweep angle parameters.

[0013] Further, step S2 specifically involves: using the CLEAN algorithm to find the location of the point with the maximum amplitude in the two-dimensional radar image, and taking this point as the target strong scattering center; then subtracting the product of the strong scattering center and the corresponding point spread function from the original image; after N iterations, when the amplitude of the maximum scattering point in the image domain is less than the required threshold, the target scattering center is extracted.

[0014] Specifically, when using the CLEAN algorithm to extract the scattering center, the selected test data needs to satisfy that the radial resolution and radial window width corresponding to the sweep frequency parameters are basically consistent with the lateral resolution and lateral window width corresponding to the sweep angle parameters, specifically: δ r =c / (2B)≈δ c =λ / (2Δφ), L r =c / (2d) f )≈L c =λ / (2δθ), where δ r For radial resolution, δ c Where L is the lateral resolution, c is the speed of light, B is the sweep bandwidth, λ is the sweep wavelength, and Δφ is the sweep width; r L is the radial window width. c d is the width of the horizontal window. f λ is the sweep frequency step size, λ is the sweep angle wavelength, and δθ is the sweep angle step size.

[0015] Furthermore, step S4 specifically involves: analyzing the strong scattering structure of the target based on its potential scattering mechanism; dividing the target into regions based on the distribution of the scattering structure on the target's geometric shape; establishing a partition model of the target's outline; and solving the boundary conditions of the target partition.

[0016] When dividing the target into regions, the boundary of the target region is defined by extending 20% ​​outward from the target outline.

[0017] Furthermore, step S5 specifically involves: extracting the distribution of the target's scattering centers from various observation angles, and grouping and focusing the scattering centers according to the target's regional division.

[0018] Furthermore, step S6 specifically involves: based on the scattering center groupings from step S5, calculating the amplitude and phase of the equivalent scattering center for each group, thereby obtaining the target's scattering point parameters at the current observation angle. The calculation formula is as follows: Where R0 is the position vector of the equivalent strong scattering point, R n Let N be the position vector of the nth scattering point, and N be the number of scattering centers in the current partition. The scattering vector of the nth scattering point. Let i be the scattering vector of the equivalent strong scattering point within the partition, where i is the imaginary unit and k is the incident electromagnetic wave number. Finally, based on the calculated position vector and scattering vector of the equivalent strong scattering point, a scattering center distribution model combining the geometric characteristics of the target is obtained.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. This invention avoids the problem of inaccurate target model description by traditional scattering center extraction methods through correlation analysis between the target's geometric shape and the distribution of scattering centers. It can realize distributed scattering center modeling that reflects the characteristics of complex target structures, greatly expanding the scope of application. Attached Figure Description

[0021] Figure 1 This is a flowchart of the method of the present invention;

[0022] Figure 2 (a) and Figure 2 (b) is a two-dimensional radar image of a vehicle target according to an embodiment of the present invention;

[0023] Figure 3 (a) and Figure 3 (b) is a two-dimensional scattering center distribution diagram of the vehicle target according to an embodiment of the present invention;

[0024] Figure 4 This is a schematic diagram of the region division of the vehicle model according to an embodiment of the present invention;

[0025] Figure 5 (a) and Figure 5 (b) is a structure-related distributed scattering center model of an embodiment of the present invention. Detailed Implementation

[0026] The technical content, structural features, objectives and effects of the present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments.

[0027] It should be noted that the accompanying drawings are in a very simplified form and use non-precise proportions. They are only used to facilitate and clarify the purpose of illustrating the embodiments of the present invention, and are not intended to limit the implementation conditions of the present invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportional relationship, or adjustments to the size should still fall within the scope of the technical content disclosed in the present invention, provided that they do not affect the effects and objectives that the present invention can produce.

[0028] It should be noted that, in this invention, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only the expressly listed elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0029] This invention provides a scattering source analysis method based on target geometry. First, scattering centers are extracted based on measured data. Then, a scattering center distribution model combining the characteristics of the target's geometry is obtained, such as... Figure 1 As shown, the extraction of scattering centers based on measured data specifically includes the following steps:

[0030] S1. Test the electromagnetic scattering characteristics of the target and obtain two-dimensional radar images of the target at different observation angles. Specific steps include:

[0031] S11. Obtain the RCS (Radar Cross Section) of the target at different azimuth angles. Specifically, a static RCS measurement system centered on a vector network analyzer is established in a microwave anechoic chamber. This system mainly includes: a radio frequency (RF) subsystem, a turntable control subsystem, and an instrument automatic control subsystem. The instrument automatic control subsystem is the core control system of the entire system, connected to the RF subsystem and the turntable control subsystem via connecting cables. The instrument automatic control subsystem controls the RF subsystem to emit electromagnetic waves of a certain frequency, controls the turntable control subsystem to rotate, and then controls the turntable control subsystem to rotate the turntable. The target's RCS is then measured using a relative comparison method, i.e., a standard object (metal plate) under the same test conditions is measured to obtain its maximum echo power, which is compared with the target's echo power to obtain the target's RCS. The calculation formula is:

[0032]

[0033] In the formula, σ s σ is the RCS of the standard body; σ is the RCS of the target; U b To measure the output response of the empty chamber receiver (the receiving device of the radio frequency subsystem); U sm To measure the output response of the standard receiver; U tmTo measure the output response of the target receiver, the target is placed on a turntable, and the turntable is used to drive the target to perform an azimuth scan, i.e., an angle scan test. During the rotation of the turntable controlled by the turntable control subsystem, for each azimuth angle, its RCS is calculated by the formula (1), and the RCS of the target at each azimuth angle (RCS in the angle scan test) can be obtained.

[0034] S12. Obtain the RCS of the target at different frequencies under the same azimuth angle and a certain bandwidth. Specifically, while using a turntable to drive the target to carry out the angle sweep test, for each azimuth angle, under a certain bandwidth, use the radio frequency subsystem to transmit electromagnetic waves with frequencies continuously changing from high to low (or from low to high), that is, carry out a frequency sweep test with a certain bandwidth. Calculate its RCS using the formula (1) to obtain the RCS of the target at different frequencies under the same azimuth angle (RCS in the frequency sweep test).

[0035] S13. A two-dimensional radar image of the target is obtained by performing Fourier transform on the RCS obtained from the frequency sweep test and the RCS obtained from the angle sweep test.

[0036] Furthermore, the two-dimensional radar image of the target is the distribution of the target's scattering center on the two-dimensional imaging plane. Its two dimensions are the radial range dimension and the lateral range dimension. The radial range dimension is related to the sweep frequency parameter, and the lateral range dimension is related to the sweep angle parameter.

[0037] S2. Extract the target scattering center from the two-dimensional radar image using the CLEAN algorithm. Specifically: the target two-dimensional radar image obtained in step S1. Affected by the window function's bandwidth and angle range, Extracting the target scattering center f(r,φ) from a 2D radar image is a deconvolution process, which is the convolution of the target scattering center f(r,φ) and the point spread function h(r,φ) (the function of the corresponding window function in the image domain). The CLEAN algorithm is an iterative algorithm. The algorithm finds the position of the point with the maximum amplitude in the image and takes this point as the strong scattering center of the target. Then, it subtracts the product of the strong scattering center and the corresponding point spread function from the original image. After N iterations, the amplitude of the maximum scattering point in the image domain is less than the required threshold. At this time, the energy of the remaining scattering center of the target is very small and does not contribute much to the overall RCS of the target. It is considered that the target scattering center has been extracted.

[0038] It should be noted that, in order to facilitate the extraction of scattering centers by the CLEAN algorithm, it is necessary to ensure that the radial resolution and radial window width corresponding to the frequency sweep parameters are basically consistent with the lateral resolution and lateral window width corresponding to the sweep angle parameters in the selected test data, as follows:

[0039] δ r =c / (2B)≈δ c=λ / (2Δφ) (2)

[0040] L r =c / (2d) f )≈L c =λ / (2δθ) (3)

[0041] In equation (2), δ r For radial resolution, δ c For lateral resolution, c is the speed of light, B is the sweep bandwidth, λ is the sweep wavelength, and Δφ is the sweep width; in equation (3), L r L is the radial window width. c d is the width of the horizontal window. f λ is the sweep frequency step size, λ is the sweep angle wavelength, and δθ is the sweep angle step size.

[0042] S3. The position of the target scattering center is transformed from the two-dimensional radar imaging plane to the target body coordinate system through coordinate transformation.

[0043] It should be noted that the scattering center extraction based on the CLEAN algorithm in step S2 only considers the strength of the scattering center energy in the radar image, and does not take into account the distribution of the scattering center in the target. In the actual application of the scattering center model, scattering centers that are clustered together may not be distinguished by the radar under test. Therefore, it is necessary to improve the method for extracting and representing the target scattering center.

[0044] The process of obtaining the scattering center distribution model that incorporates the geometric characteristics of the target includes the following steps:

[0045] S4. Divide the target model into regions. Specifically, based on the target's potential scattering mechanism, analyze the target's strong scattering structure. Based on the distribution of the scattering structure on the target's geometric shape, divide the target into regions, establish a partition model of the target contour, and solve the boundary conditions of the target partition.

[0046] It should be noted that, considering that the location of the scattering center caused by multipath scattering between target components may deviate from the target itself, when dividing the target into regions, the target outline is used as the reference and extended outward by 20% as the boundary of the target partition.

[0047] Specifically, target scattering mechanisms include surface scattering, multiple scattering, edge diffraction, vertex and apex diffraction, surface crawling wave and creeping wave scattering, etc. For the same scattering mechanism, there are also many variations in target geometry. For example, the geometry corresponding to surface scattering includes flat plates, cylinders, spheres, etc., while the geometry corresponding to multiple scattering includes dihedrals, cap tops, trihedrals, etc.

[0048] S5. The scattering centers are classified and focused according to the regions. Specifically, the distribution of the scattering centers of the target is extracted from various observation angles. The number of extracted scattering centers is large and relatively discrete. The scattering centers are grouped, classified and focused according to the region of the target, and the target is described using a limited number of scattering centers.

[0049] S6. Obtain a scattering center distribution model that incorporates the target's geometric characteristics. Specifically, according to the scattering center grouping in step S5, calculate the amplitude and phase of the equivalent scattering center for each group to obtain the target's scattering point parameters at the current observation angle. The calculation formula is as follows:

[0050]

[0051]

[0052] In the formula, R0 is the position vector of the equivalent strong scattering point; R n The position vector of the nth scattering point; N is the number of scattering centers in the current partition; This is the scattering vector of the nth scattering point; is the scattering vector of the equivalent strong scattering point within the partition; i is the imaginary unit; k is the incident electromagnetic wave number. Based on the calculated position vector and scattering vector of the equivalent strong scattering point, a scattering center distribution model combining the geometric characteristics of the target is obtained.

[0053] In this preferred embodiment, taking the analysis of scattering sources related to the geometric shape of a vehicle target as an example, firstly, a static RCS measurement system is used in a microwave anechoic chamber to conduct an angle-scanning test on the vehicle target at a certain frequency and bandwidth to acquire electromagnetic scattering data. Then, imaging processing is performed based on the electromagnetic scattering data to obtain two-dimensional radar images of the target at different observation angles. Specifically, as shown... Figure 2 As shown, imaging processing was performed on test data of a vehicle target at a frequency of 77 GHz, a bandwidth of 1 GHz, and azimuth angles of 0° (incidence from the head direction) and 45° to obtain a two-dimensional radar image of the vehicle target. Figure 2 (a) is a two-dimensional radar image of a vehicle target at an azimuth angle of 0°. Figure 2 (b) is a two-dimensional radar image of a vehicle target at an azimuth angle of 45°.

[0054] Subsequently, based on the acquired two-dimensional radar image of the vehicle target, the CLEAN algorithm is used to extract the scattering centers, obtaining a scattering center distribution map under the radar imaging plane, as shown below. Figure 3 As shown, the number of scattering centers selected for each two-dimensional radar image is 20. Figure 3 The scattering centers are marked with "+", where, Figure 3(a) is a distribution of the scattering centers of a vehicle target under the radar imaging plane at an azimuth angle of 0°. Figure 3 (b) is a distribution map of the scattering centers of a vehicle target under the radar imaging plane at an azimuth angle of 45°. Figure 3 (a) and Figure 3 (b) It is visible that the scattering center is mainly concentrated in the area of ​​the vehicle target illuminated by radar waves.

[0055] The scattering center data is transformed from the radar imaging plane to the vehicle target coordinate system through coordinate transformation.

[0056] Based on the potential scattering mechanism of vehicle targets, the strong scattering structure of vehicle targets is analyzed. The geometric structure of vehicle targets such as the front, rear, body, and rearview mirrors is mostly composed of typical geometric bodies, such as flat plates, first-order curved surfaces, hyperboloids, cylinders, and spires. Among them, flat plates correspond to planar scattering, cones and cylinders correspond to single-order surface scattering, spheres or hyperboloids correspond to hyperboloid scattering, and wedges, curved edges, and spires correspond to diffraction.

[0057] Based on the above analysis of the strong scattering structure of the vehicle target, the target area is divided into regions. Specifically, the length of the vehicle target along the X-axis is denoted as L, the width along the Y-axis as W, and the geometric center of the vehicle target is located at the origin. The range of values ​​for the X-axis in the region division is -0.6L to 0.6L, and the range of values ​​for the Y-axis is -0.6W to 0.6W. Figure 4 As shown, the vehicle target is divided into 12 typical zones, from zone A to zone L. The main scattering center types and boundary constraints corresponding to each zone are as follows, where x and y are the coordinates of the corresponding scattering centers:

[0058] (a) Region A: The specular scattering center of the area near the normal incidence.

[0059] 0.4L < x ≤ 0.6L

[0060] -0.4W≤y≤0.4W

[0061] (b) Area B: The scattering center corresponding to the left front corner of the vehicle

[0062] 0.3L < x ≤ 0.6L

[0063] 0.4W < y ≤ 0.6W

[0064] (c) Area C: The scattering center corresponding to the intersection point to the right front of the vehicle.

[0065] 0.3L < x ≤ 0.6L

[0066] -0.6W ≤ y < -0.4W

[0067] (d) Area D: The scattering center corresponding to the vehicle's left front wheel, left front door, and left rearview mirror is 0≤x≤0.3L

[0068] 0.4W < y ≤ 0.6W

[0069] (e) Zone E: The scattering center corresponding to the right front wheel, right front door, and right side mirror of the vehicle is 0≤x≤0.3L

[0070] -0.6W ≤ y < -0.4W

[0071] (f) Area F: Radiation center corresponding to the left rear wheel and left rear door of the vehicle

[0072] -0.3L≤x<0

[0073] 0.4W < y ≤ 0.6W

[0074] (g) Area G: Scattering center corresponding to the right rear wheel and right rear door of the vehicle

[0075] -0.3L≤x<0

[0076] -0.6W ≤ y < -0.4W

[0077] (h) H area: The scattering center corresponding to the left rear corner of the vehicle

[0078] -0.6L ≤ x < -0.3L

[0079] 0.4W < y ≤ 0.6W

[0080] (i) Area I: The scattering center corresponding to the right rear corner of the vehicle

[0081] -0.6L ≤ x < -0.3L

[0082] -0.6W ≤ y < -0.4W

[0083] (j) J region: the specular scattering center of the vehicle's rear area.

[0084] -0.6L ≤ x < -0.4L

[0085] -0.4W≤y≤0.4W

[0086] (k) K region: the scattering center corresponding to the rear section of the vehicle body

[0087] -0.4L≤x<0

[0088] -0.4W≤y≤0.4W

[0089] (l) L area: the scattering center corresponding to the front part of the vehicle body

[0090] 0≤x≤0.4L

[0091] -0.4W≤y≤0.4W

[0092] Will Figure 3 The scattering centers of the vehicle targets obtained in the data are categorized and focused according to 12 zones, such as... Figure 5 As shown, a distributed scattering center model of the vehicle target that reflects the geometric characteristics of the target is obtained, and the scattering centers are marked with black dots. Figure 5 (a) is a scattering center model based on the vehicle target geometry at an azimuth angle of 0°. Figure 5 (b) is the scattering center model based on the vehicle target geometry at an azimuth angle of 45°.

[0093] In summary, compared with the prior art, the scattering source analysis method based on the target geometry proposed in this invention avoids the problems of inaccurate target model description by traditional scattering center extraction methods by analyzing the correlation between the target geometry and the distribution of scattering centers. It can realize distributed scattering center modeling that reflects the characteristics of complex target structures, and greatly expands the scope of application.

[0094] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A method for analyzing scattering sources based on the geometry of a target, characterized in that, It includes the following two steps: First, the scattering center is extracted based on the measured data of the target, specifically including: S1, acquiring a two-dimensional radar image; S2, extracting the scattering center; S3, converting the scattering center data to the target body coordinate system. The following steps involve obtaining a scattering center distribution model that incorporates the characteristics of the target's geometric structure, specifically including: S4, dividing the target model into partitions; S5, classifying and focusing the scattering centers according to the partitions; and S6, obtaining a scattering center distribution model related to the geometric structure. Step S4 specifically includes: analyzing the strong scattering structure of the target based on the target's potential scattering mechanism, dividing the target into regions based on the distribution of the scattering structure on the target's geometric shape, establishing a partition model of the target's outline, and solving the boundary conditions of the target partition. Step S5 specifically includes: extracting the distribution of the target's scattering centers from various observation angles, and grouping and focusing the scattering centers according to the target's regional division; Specifically, step S6 involves: calculating the position vector and scattering vector of the equivalent strong scattering point based on the scattering center grouping obtained in step S5, and obtaining a scattering center distribution model that combines the geometric characteristics of the target.

2. The scattering source analysis method based on target geometry as described in claim 1, characterized in that, Step S1 specifically includes: S11. Establish a static RCS measurement system with a vector network analyzer as the core in a microwave anechoic chamber. The system mainly includes: radio frequency subsystem, turntable control system and instrument automatic control subsystem. Place the target on the turntable and use the turntable to drive the target to perform azimuth angle scanning, i.e., angle scanning test, to obtain the RCS of the target at each azimuth angle, i.e., the RCS of the angle scanning test. S12. While using the turntable to drive the target to carry out the angle sweep test, a frequency sweep test is carried out for each azimuth angle to obtain the RCS of the target at different frequencies in each azimuth angle, that is, the RCS of the frequency sweep test. S13. A two-dimensional radar image of the target is obtained by performing Fourier transform on the RCS of the frequency sweep test and the RCS of the angle sweep test.

3. The scattering source analysis method based on target geometry as described in claim 2, characterized in that, The calculation methods for the RCS of the sweep angle test and the sweep frequency test in step S1 are as follows: A standard body under the same test conditions is measured to obtain the maximum value of the standard body's echo power. This value is then compared with the echo power of the target to obtain the target's RCS. The calculation formula is as follows: ,in, It is the RCS of the standard body. It is the target's RCS. To measure the output response of the empty chamber receiver, To measure the output response of the standard receiver, To measure the output response of the target receiver.

4. The scattering source analysis method based on target geometry as described in claim 2, characterized in that, The two dimensions of a target's two-dimensional radar image are the radial range dimension and the lateral range dimension. The radial range dimension is related to the sweep frequency parameters, while the lateral range dimension is related to the sweep angle parameters.

5. The scattering source analysis method based on target geometry as described in claim 2, characterized in that, Step S2 specifically involves: using the CLEAN algorithm to find the location of the point with the maximum amplitude in the two-dimensional radar image, and taking this point as the strong scattering center of the target. Then, subtract the product of the strong scattering center and the corresponding point spread function from the original image. After N iterations, when the amplitude of the maximum scattering point in the image domain is less than the required threshold, the target scattering center is extracted.

6. The scattering source analysis method based on target geometry as described in claim 5, characterized in that, When using the CLEAN algorithm to extract scattering centers, the selected test data needs to meet the following requirements: the radial resolution and radial window width corresponding to the sweep frequency parameters are basically consistent with the lateral resolution and lateral window width corresponding to the sweep angle parameters. Specifically: , ,in, For radial resolution, For horizontal resolution, At the speed of light, For the sweep bandwidth, For the sweep wavelength, This refers to the sweeping angle width; Radial window width, The width of the horizontal window. For the sweep step size, For the sweep wavelength, This is the sweeping step size.

7. The scattering source analysis method based on target geometry as described in claim 6, characterized in that, When dividing the target into regions, the boundary of the target region is defined by extending 20% ​​outward from the target outline.

8. The scattering source analysis method based on target geometry as described in claim 7, characterized in that, Step S6 specifically involves: calculating the amplitude and phase of the equivalent scattering centers of each group to obtain the scattering point parameters of the target at the current observation angle. The calculation formula is as follows: , ,in, The position vector of the equivalent strong scattering point. Let n be the position vector of the nth scattering point. This represents the number of scattering centers within the current partition. The scattering vector of the nth scattering point. This represents the scattering vector of the equivalent strong scattering point within the partition. The imaginary unit, The incident electromagnetic wave number is denoted as .

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