阅读说明：本技术 基于弹跳射线法的双站散射中心建模方法 (Double-station scattering center modeling method based on bounce ray method ) 是由 张磊 闫华 陆金文 李胜 于 2020-12-25 设计创作，主要内容包括：本发明涉及雷达技术领域,特别是一种基于弹跳射线法的双站散射中心建模方法。通过目标几何建模及剖分,形成目标网格模型,然后通过基于弹跳射线法的双站射线路径和散射场计算方法、双站射线位置等效方法、基于图像域射线管积分的三维双站ISAR图像快速生成方法和基于CLEAN的散射中心提取算法实现了目标双站散射中心模型的构建；整个建模过程效率高、散射机理清晰,构建出的散射中心模型与目标几何模型有着良好的对应关系,可为协同探测、网络化雷达、MIMO-SAR等新体制雷达系统仿真、数据快速生成、目标检测识别等应用提供有力技术支撑。(The invention relates to the technical field of radars, in particular to a double-station scattering center modeling method based on a bounce ray method. Forming a target grid model through geometric modeling and subdivision of a target, and then realizing construction of the target two-station scattering center model through a double-station ray path and scattered field calculation method based on a bounce ray method, a double-station ray position equivalent method, a three-dimensional double-station ISAR image rapid generation method based on image domain ray tube integration and a scattering center extraction algorithm based on CLEAN; the whole modeling process is high in efficiency and clear in scattering mechanism, the constructed scattering center model has a good corresponding relation with the target geometric model, and powerful technical support can be provided for application of cooperative detection, networked radar, MIMO-SAR and other new system radar system simulation, data rapid generation, target detection and identification and the like.)

1. A double-station scattering center modeling method based on a bounce ray method comprises the following steps:

s1, carrying out geometric modeling and subdivision on the target to form a target mesh model;

s2, calculating ray paths and scattered field data under the double-station condition based on a bounce ray method;

s3, according to the optical path difference equivalent relation and the relation of the optical path changing rate along with the attitude angle, the ray double-station multi-acting path position is equivalent to a double-station single-acting position;

s4, rapidly generating a target three-dimensional double-station ISAR image by using an image domain ray tube integration mode;

s5, extracting target double-station scattering center model parameters from the target three-dimensional double-station ISAR image by using a CLEAN algorithm so as to construct a target double-station scattering center model.

2. The bounce ray method-based dual-station scattering center modeling method according to claim 1, wherein the target is geometrically modeled and subdivided to form a target mesh model,

and (3) constructing a geometric model of the target by using modeling software, and then performing mesh generation on the geometric model to form a target mesh model.

3. The dual-station scatter center modeling method based on the bounce ray method according to claim 2, wherein in calculating ray path and scatter field data under dual-station conditions based on the bounce ray method,

far-field electromagnetic waves emitted by the radar are regarded as a series of parallel rays by using a bouncing ray method:

[ray₁,ray₂,...,ray_i,...,ray_N]where i ∈ [1, N ]]Represents the ith ray number; when the parallel rays irradiate the target grid model along the set incidence direction, multiple reflections occur on the target surface, and bounce paths [ path ] of all rays are tracked and recorded according to a geometric optics method₁,path₂,...,path_i,...,path_N]Let the ith ray path be path_i＝[p_i1,p_i2,...,p_ij,...,p_iM]Wherein p is_ij＝[x_ij；y_ij；z_ij]The position of the ray at the jth bounce point; after a plurality of bounces, the ray leaves the surface of the target to generate emergence, and the electric field [ E ] generated along the set receiving direction of the ray is calculated at the emergence point by a physical optical method₁,E₂,...,E_i,...,E_N]。

4. The method for modeling the double-station scattering center based on the bounce ray method according to claim 3, wherein the ray double-station multi-action path position is equivalent to the double-station single-action position according to the optical path difference equivalent relation and the optical path change rate relation with the attitude angle,

converting the position of a first bounce point in a ray path obtained by tracking under a target coordinate system into a position under a radar coordinate system along an incident direction, and converting the position of a last bounce point in the ray path into a radar seat along an emergent directionA position under the mark; the position p of a first bounce point of the ith ray in a target coordinate system_i1＝[x_i1；y_i1；z_i1]And the position p of the last bounce point_iM＝[x_iM；y_iM；z_iM]Respectively converted into bounce positions p 'under a radar coordinate system according to a coordinate transformation formula'_i1＝[x'_i1；y'_i1；z'_i1]And p'_iM＝[x'_iM；y'_iM；z'_iM](ii) a The coordinate transformation formula is as follows:

wherein θ anda pitch angle and an azimuth angle in the incident or receiving direction, respectively; based on the obtained bounce position under the radar coordinate system, deducing and determining the equivalent position of the multiple actions of the double-station rays under the radar coordinate system according to the optical path difference equivalent relation and the relation of the optical path changing rate along with the attitude angle; the ith ray has equivalent position p 'under a radar coordinate system'_i＝[x'_i；y'_i；z'_i]The calculation formula of (2) is as follows:

wherein d is_jIndicating the distance from the jth bounce point to the jth-1 bounce point of the ray.

5. The double-station scattering center modeling method based on the bounce ray method according to claim 4, characterized in that an image domain tube integral mode is used for rapidly generating a three-dimensional double-station ISAR image of a target,

deriving a closed expression of the image domain ray tube integral under the small aperture angle according to a single-station and double-station equivalent principle based on the ray electric field obtained in the step S2 and the ray equivalent position obtained in the step S3; the integral calculation formula of the image domain ray tube of the ith ray is as follows:

Image3D_Rayi(x,y,z)＝E_ih(x-x'_i,y-y'_i,z-z'_i)

wherein k is₀Is the wave number, delta k is the wave number width, delta theta is the pitch angle width, and delta phi azimuth angle width; after an image domain ray tube integral result of each ray is obtained through calculation, all ray results are superposed to obtain a total three-dimensional double-station ISAR image of the target:

6. the bounce ray method-based double-station scattering center modeling method based on the claim 5, characterized in that a CLEAN algorithm is adopted to extract model parameters of the target double-station scattering center from a three-dimensional double-station ISAR image of the target,

suppose that the three-dimensional double-station ISAR image of the target consists of Q independent point scattering centers SC₁,SC₂,...,SC_n,...,SC_Q]Each scattering center is formed by an amplitude parameter A_nAnd a position parameter p under the target coordinate system_n＝[x_n；y_n；z_n]And (3) representing, namely, the target three-dimensional double-station ISAR image is obtained by overlapping and approximating the scattering center after image domain integration, and the formula of the target three-dimensional double-station ISAR image obtained by overlapping and approximating is as follows:

wherein p'_n＝[x'_n；y'_n；z'_n]The position parameters of the scattering center under a radar coordinate system are obtained; obtaining a target three-dimensional double-station ISAR image formula based on superposition approximation, and extracting the scattering center by adopting a CLEAN algorithm through circulating the following processes until the amplitude of the strongest point of the image is smaller than a set threshold value: firstly, extracting the intensity and the position of the strongest point in a target three-dimensional double-station ISAR image as the amplitude of a scattering center and the position of the scattering center under a radar coordinate system, then subtracting the integral result of the scattering center in an image domain from the ISAR image, wherein the residual image of the nth cycle is as follows:

(ResidualImage3D)_n+1＝(ResidualImage3D)_n-[A_nh(x-x'_n,y-y'_n,z-z'_n)]

wherein A is_nIs the amplitude, p 'of the extracted nth scattering center'_n＝[x'_n；y'_n；z'_n]The extracted position of the nth scattering center in a radar coordinate system; after the extraction of the scattering center is finished, converting the lower position of the radar coordinate system of the double-station scattering center into the lower position of a target coordinate system; the coordinate transformation formula of the nth scattering center position is as follows:

wherein the content of the first and second substances,representing the pitch and azimuth angles of the incident direction,a pitch angle and an azimuth angle representing a reception direction,in the incident and receiving directions in step S3, respectivelyThe superscript "-1" indicates the matrix inversion.

Technical Field

The invention relates to the technical field of radars, in particular to a double-station scattering center modeling method based on a bounce ray method.

Background

The new system radar technologies such as cooperative detection, networked radar, MIMO-SAR and the like can acquire multi-angle double/multi-station scattering information of the target, and have great potential in the aspect of improving the target detection and identification capabilities. Currently, for the new system radar, the existing research mainly focuses on radar station arrangement, coherent processing, imaging and the like, but the research on the aspects of complex target double-station scattering mechanism, feature extraction and identification and the like is relatively less.

The target scattering center parameterized model is a scattering mechanism representation-based target scattering model with a concise analytic expression form, and can be used for not only fast generation of radar signals/scene data, but also mining of deep-level attribute features of a target. From the last 90 s to the present, scholars at home and abroad propose a plurality of electromagnetic scattering parametric model forms and modeling methods. Proposed representative parameterized models include: prony model, GTD model, attribute scattering center model, etc. have obtained better effect in the practical application. However, most of the models are established for a single-station situation, and the target double-station scattering mechanism and characteristics cannot be effectively described. Although partial models, such as a typical scattering feature model, can express the characteristic of the two-station scattering, because the research on the mechanism of the two-station scattering is not deep enough, a reliable and effective two-station scattering center model cannot be constructed at present.

Therefore, in order to solve the above problems, it is necessary to establish a target two-station scattering center parameterized model based on a two-station scattering mechanism, solve the difficult problem of complex target two-station scattering parameterized modeling, and provide technical support for applications such as rapid generation of scene data and target identification under radar detection of a new system.

Disclosure of Invention

The invention aims to provide a double-station scattering center modeling method based on a bounce ray method, and solves the problem that a reliable and effective double-station scattering center model cannot be constructed in the past.

One aspect of the application provides a double-station scattering center modeling method based on a bounce ray method, which comprises the following steps:

s1, carrying out geometric modeling and subdivision on the target to form a target mesh model;

s2, calculating ray paths and scattered field data under the double-station condition based on a bounce ray method;

s3, according to the optical path difference equivalent relation and the relation of the optical path changing rate along with the attitude angle, the ray double-station multi-acting path position is equivalent to a double-station single-acting position;

s4, rapidly generating a target three-dimensional double-station ISAR image by using an image domain ray tube integration mode;

s5, extracting target double-station scattering center model parameters from the target three-dimensional double-station ISAR image by using a CLEAN algorithm so as to construct a target double-station scattering center model.

Wherein, the target geometric modeling and subdivision are carried out to form a target mesh model,

and (3) constructing a geometric model of the target by using modeling software, and then performing mesh generation on the geometric model to form a target mesh model.

Wherein, in calculating ray path and scattered field data under the double-station condition based on the bounce ray method,

far-field electromagnetic waves emitted by the radar are regarded as a series of parallel rays by using a bouncing ray method:

[ray₁,ray₂,...,ray_i,...,ray_N]where i ∈ [1, N ]]Represents the ith ray number; when the parallel rays irradiate the target grid model along the set incidence direction, multiple reflections occur on the target surface, and bounce paths [ path ] of all rays are tracked and recorded according to a geometric optics method₁,path₂,...,path_i,...,path_N]Let the ith ray path be path_i＝[p_i1,p_i2,...,p_ij,...,p_iM]Wherein p is_ij＝[x_ij；y_ij；z_ij]The position of the ray at the jth bounce point; after a plurality of bounces, the ray leaves the surface of the target to generate emergence, and the electric field [ E ] generated along the set receiving direction of the ray is calculated at the emergence point by a physical optical method₁,E₂,...,E_i,...,E_N]。

Wherein, the ray double-station multi-action path position is equivalent to the double-station single-action position according to the optical path difference equivalent relation and the relation of the optical path changing rate along with the attitude angle,

converting the position of a first bounce point in a ray path obtained by tracking under a target coordinate system into a position under a radar coordinate system along the incident direction, and converting the position of a last bounce point in the ray pathConverting the position of the radar coordinate system into a position along the emergent direction; the position p of a first bounce point of the ith ray in a target coordinate system_i1＝[x_i1；y_i1；z_i1]And the position p of the last bounce point_iM＝[x_iM；y_iM；z_iM]Respectively converted into bounce positions p 'under a radar coordinate system according to a coordinate transformation formula'_i1＝[x'_i1；y'_i1；z'_i1]And p'_iM＝[x'_iM；y'_iM；z'_iM](ii) a The coordinate transformation formula is as follows:

wherein θ anda pitch angle and an azimuth angle in the incident or receiving direction, respectively; based on the obtained bounce position under the radar coordinate system, deducing and determining the equivalent position of the multiple actions of the double-station rays under the radar coordinate system according to the optical path difference equivalent relation and the relation of the optical path changing rate along with the attitude angle; the ith ray has equivalent position p 'under a radar coordinate system'_i＝[x'_i；y'_i；z'_i]The calculation formula of (2) is as follows:

wherein d is_jIndicating the distance from the jth bounce point to the jth-1 bounce point of the ray.

Wherein, the three-dimensional double-station ISAR image of the target is rapidly generated by utilizing an image domain ray tube integral mode,

deriving a closed expression of the image domain ray tube integral under the small aperture angle according to a single-station and double-station equivalent principle based on the ray electric field obtained in the step S2 and the ray equivalent position obtained in the step S3; the integral calculation formula of the image domain ray tube of the ith ray is as follows:

Image3D_Rayi(x,y,z)＝E_ih(x-x'_i,y-y'_i,z-z'_i)

wherein k is₀Is the wave number, delta k is the wave number width, delta theta is the pitch angle width, and delta phi azimuth angle width; after an image domain ray tube integral result of each ray is obtained through calculation, all ray results are superposed to obtain a total three-dimensional double-station ISAR image of the target:

wherein, the CLEAN algorithm is adopted to extract model parameters of the target double-station scattering center from the target three-dimensional double-station ISAR image,

suppose that the three-dimensional double-station ISAR image of the target consists of Q independent point scattering centers SC₁,SC₂,...,SC_n,...,SC_Q]Each scattering center is formed by an amplitude parameter A_nAnd a position parameter p under the target coordinate system_n＝[x_n；y_n；z_n]And (3) representing, namely, the target three-dimensional double-station ISAR image is obtained by overlapping and approximating the scattering center after image domain integration, and the formula of the target three-dimensional double-station ISAR image obtained by overlapping and approximating is as follows:

wherein p'_n＝[x'_n；y'_n；z'_n]The position parameters of the scattering center under a radar coordinate system are obtained; obtaining a target three-dimensional double-station ISAR image formula based on superposition approximation, and realizing dispersion by adopting a CLEAN algorithm through the following processes until the amplitude of the strongest point of the image is smaller than a set threshold valueExtraction of shot centers: firstly, extracting the intensity and the position of the strongest point in a target three-dimensional double-station ISAR image as the amplitude of a scattering center and the position of the scattering center under a radar coordinate system, then subtracting the integral result of the scattering center in an image domain from the ISAR image, wherein the residual image of the nth cycle is as follows:

(Residual Image3D)_n+1＝(Residual Image3D)_n-[A_nh(x-x'_n,y-y'_n,z-z'_n)]

wherein A is_nIs the amplitude, p 'of the extracted nth scattering center'_n＝[x'_n；y'_n；z'_n]The extracted position of the nth scattering center in a radar coordinate system; after the extraction of the scattering center is finished, converting the lower position of the radar coordinate system of the double-station scattering center into the lower position of a target coordinate system; the coordinate transformation formula of the nth scattering center position is as follows:

wherein the content of the first and second substances,representing the pitch and azimuth angles of the incident direction,a pitch angle and an azimuth angle representing a reception direction,in the incident and receiving directions in step S3, respectivelyThe superscript "-1" indicates the matrix inversion.

The scheme shows that the invention has the following beneficial effects:

according to the method, a target grid model is formed through geometric modeling and subdivision of a target, and then the construction of the target two-station scattering center model is realized through a double-station ray path and scattering field calculation method based on a bounce ray method, a double-station ray position equivalent method, a three-dimensional double-station ISAR image rapid generation method based on image domain ray tube integration and a scattering center extraction algorithm based on CLEAN; the whole modeling process is high in efficiency and clear in scattering mechanism, the constructed scattering center model has a good corresponding relation with the target geometric model, powerful technical support can be provided for application of cooperative detection, new-system radar system simulation of networked radar, MIMO-SAR and the like, data rapid generation, target detection and identification and the like, and the model is reliable and effective.

Drawings

FIG. 1 is a schematic flow chart of a double-station scattering center modeling method based on a bounce ray method;

FIG. 2 is a schematic diagram of a modeling principle of a double-station scattering center modeling method based on a bounce ray method;

FIG. 3 is a schematic diagram of a dihedral target geometry model in the present application;

FIG. 4 is a schematic diagram of a dihedral target mesh model in the present application;

FIG. 5 is a schematic view of the ray path and the scattered field in the present application;

FIG. 6 is a schematic diagram of the ray equivalent location in the present application;

FIG. 7 is a schematic diagram of a dihedral target three-dimensional dual-station ISAR in the present application;

FIG. 8 is a schematic diagram of a three-dimensional two-station scattering center of a dihedral target according to the present application corresponding to a geometric model.

Detailed Description

As shown in fig. 1 to 8, a method for modeling a dual-station scattering center based on a bounce ray method provided by an embodiment of the present invention includes the following steps:

s1, carrying out geometric modeling and subdivision on the target to form a target mesh model;

s2, calculating ray paths and scattered field data under the double-station condition based on a bounce ray method;

s3, according to the optical path difference equivalent relation and the relation of the optical path changing rate along with the attitude angle, the ray double-station multi-acting path position is equivalent to a double-station single-acting position;

s4, rapidly generating a target three-dimensional double-station ISAR image by using an image domain ray tube integration mode;

s5, extracting target double-station scattering center model parameters from the target three-dimensional double-station ISAR image by using a CLEAN algorithm so as to construct a target double-station scattering center model.

In the embodiment, a target grid model is formed by geometric modeling and subdivision of a target, and then the construction of the target two-station scattering center model is realized by a double-station ray path and scattering field calculation method based on a bounce ray method, a double-station ray position equivalent method, a three-dimensional double-station ISAR image rapid generation method based on image domain ray tube integration and a scattering center extraction algorithm based on CLEAN; the whole modeling process is high in efficiency and clear in scattering mechanism, the constructed scattering center model has a good corresponding relation with the target geometric model, and powerful technical support can be provided for application of cooperative detection, networked radar, MIMO-SAR and other new system radar system simulation, data rapid generation, target detection and identification and the like.

The method comprises the following specific implementation steps:

1. modeling and subdividing the target geometry: firstly, a geometric model of a target is constructed by utilizing CAD modeling software (such as ANSYS, Hypermesh and the like), and a geometric model of a dihedral angle target constructed by utilizing Hypermesh is shown in FIG. 3; and then, mesh generation is carried out on the constructed target geometric model, and the generated target mesh model is shown in FIG. 4.

2. After the parameters of the double-station radar such as the incident direction (incident pitch angle and azimuth angle) of electromagnetic waves, the receiving direction (receiving pitch angle and azimuth angle), the frequency and the receiving and transmitting polarization are set, the ray bounce path and the scattered electric field under the double-station condition are calculated by using a GO-PO electromagnetic simulation algorithm. FIG. 5 shows the ith ray path under the polarization of transmitting/receiving VV with the electromagnetic wave incident at a pitch angle of 90 degrees, an azimuth angle of-30 degrees, a receiving pitch angle of 90 degrees, an azimuth angle of 30 degrees, and a frequency of 16GHz_iAnd a scattered field E_iSchematic representation.

3. Firstly, converting the position of a first bounce point and the position of a last bounce point of a ray in a target coordinate system according to an incident direction, a receiving direction and a coordinate transformation formulaThe ray bounce position under the radar coordinate system is obtained; then, substituting the ray bounce position under the radar coordinate system into a double-station ray multi-action equivalent position calculation formula to solve the target double-station ray equivalent position under the radar coordinate system; FIG. 6 shows the two-time action position p of the ith ray in the target coordinate system under the two-station condition_i1、p_i2Equivalent is equivalent position p 'under radar coordinate system'_iSchematic representation of (a).

4. After setting imaging parameters such as wave number width, pitch angle width, azimuth angle width and the like, introducing ray equivalent position and ray scattering field data under a radar coordinate system into an image domain ray tube integral calculation formula, and accumulating to obtain a target three-dimensional double-station ISAR image; fig. 7 shows a three-dimensional dual-station ISAR image of a dihedral target at a wavenumber width of 20.9440rad/m, a pitch angle width of 5.7296 °, and an azimuth angle width of 5.7296 ° (corresponding to a 0.15m image resolution).

5. Setting a CLEAN algorithm extraction threshold, and extracting the range of the target three-dimensional double-station scattering center and the position under a radar coordinate system from the target three-dimensional double-station ISAR image by utilizing a CLEAN algorithm and a residual image calculation formula. And then, the scattering center position, the incidence direction and the receiving direction under the radar coordinate system are taken into a scattering center position coordinate transformation formula to solve the scattering center position under the target coordinate system. The position and the amplitude of a scattering center under a target coordinate system form a target three-dimensional double-station scattering center model; FIG. 8 shows a corresponding diagram of the extracted dihedral angle target three-dimensional two-station scattering center and the geometric model when the CLEAN algorithm threshold is 30dB below the maximum value of the ISAR image.

Wherein, in calculating ray path and scattered field data under the double-station condition based on the bounce ray method,

far-field electromagnetic waves emitted by the radar are regarded as a series of parallel rays by using a bouncing ray method:

[ray₁,ray₂,...,ray_i,...,ray_N]where i ∈ [1, N ]]Represents the ith ray number; when the parallel rays irradiate the target grid model along the set incidence direction, multiple reflections occur on the target surface, and the bounce paths of all the rays are tracked and recorded according to a geometric optics methodPath (path)₁,path₂,...,path_i,...,path_N]Let the ith ray path be path_i＝[p_i1,p_i2,...,p_ij,...,p_iM]Wherein p is_ij＝[x_ij；y_ij；z_ij]The position of the ray at the jth bounce point; after a plurality of bounces, the ray leaves the surface of the target to generate emergence, and the electric field [ E ] generated along the set receiving direction of the ray is calculated at the emergence point by a physical optical method₁,E₂,...,E_i,...,E_N]。

Wherein, the ray double-station multi-action path position is equivalent to the double-station single-action position according to the optical path difference equivalent relation and the relation of the optical path changing rate along with the attitude angle,

converting a first bounce point position in a ray path obtained by tracking under a target coordinate system into a position under a radar coordinate system along an incident direction, and converting a last bounce point position in the ray path into a position under the radar coordinate system along an emergent direction; the position p of a first bounce point of the ith ray in a target coordinate system_i1＝[x_i1；y_i1；z_i1]And the position p of the last bounce point_iM＝[x_iM；y_iM；z_iM]Respectively converted into bounce positions p 'under a radar coordinate system according to a coordinate transformation formula'_i1＝[x'_i1；y'_i1；z'_i1]And p'_iM＝[x'_iM；y'_iM；z'_iM](ii) a The coordinate transformation formula is as follows:

wherein θ andpitching in incident or receiving direction, respectivelyAngle and azimuth; based on the obtained bounce position under the radar coordinate system, deducing and determining the equivalent position of the multiple actions of the double-station rays under the radar coordinate system according to the optical path difference equivalent relation and the relation of the optical path changing rate along with the attitude angle; the ith ray has equivalent position p 'under a radar coordinate system'_i＝[x'_i；y'_i；z'_i]The calculation formula of (2) is as follows:

wherein d is_jIndicating the distance from the jth bounce point to the jth-1 bounce point of the ray.

In particular, in the method of utilizing image domain tube integration to quickly generate a target three-dimensional double-station ISAR image,

deriving a closed expression of the image domain ray tube integral under the small aperture angle according to a single-station and double-station equivalent principle based on the ray electric field obtained in the step S2 and the ray equivalent position obtained in the step S3; the integral calculation formula of the image domain ray tube of the ith ray is as follows:

Image3D_Rayi(x,y,z)＝E_ih(x-x'_i,y-y'_i,z-z'_i)

wherein k is₀Is the wave number, delta k is the wave number width, delta theta is the pitch angle width, and delta phi azimuth angle width; after an image domain ray tube integral result of each ray is obtained through calculation, all ray results are superposed to obtain a total three-dimensional double-station ISAR image of the target:

specifically, a CLEAN algorithm is adopted to extract model parameters of the target double-station scattering center from a target three-dimensional double-station ISAR image,

suppose a target three-dimensional dual-station ISARThe image consists of Q independent point scattering centers [ SC₁,SC₂,...,SC_n,...,SC_Q]Each scattering center is formed by an amplitude parameter A_nAnd a position parameter p under the target coordinate system_n＝[x_n；y_n；z_n]And (3) representing, namely, the target three-dimensional double-station ISAR image is obtained by overlapping and approximating the scattering center after image domain integration, and the formula of the target three-dimensional double-station ISAR image obtained by overlapping and approximating is as follows:

wherein p'_n＝[x'_n；y'_n；z'_n]The position parameters of the scattering center under a radar coordinate system are obtained; obtaining a target three-dimensional double-station ISAR image formula based on superposition approximation, and extracting the scattering center by adopting a CLEAN algorithm through circulating the following processes until the amplitude of the strongest point of the image is smaller than a set threshold value: firstly, extracting the intensity and the position of the strongest point in a target three-dimensional double-station ISAR image as the amplitude of a scattering center and the position of the scattering center under a radar coordinate system, then subtracting the integral result of the scattering center in an image domain from the ISAR image, wherein the residual image of the nth cycle is as follows:

(Residual Image3D)_n+1＝(Residual Image3D)_n-[A_nh(x-x'_n,y-y'_n,z-z'_n)]

wherein A is_nIs the amplitude, p 'of the extracted nth scattering center'_n＝[x'_n；y'_n；z'_n]The extracted position of the nth scattering center in a radar coordinate system; after the extraction of the scattering center is finished, converting the lower position of the radar coordinate system of the double-station scattering center into the lower position of a target coordinate system; the coordinate transformation formula of the nth scattering center position is as follows:

wherein the content of the first and second substances,representing the pitch and azimuth angles of the incident direction,a pitch angle and an azimuth angle representing a reception direction,in the incident and receiving directions in step S3, respectivelyThe superscript "-1" indicates the matrix inversion.

In conclusion, the modeling method provided by the application has high efficiency in the modeling process and clear scattering mechanism, the constructed scattering center model has good corresponding relation with the target geometric model, and powerful technical support can be provided for the applications of cooperative detection, networked radar, MIMO-SAR and other new system radar system simulation, data rapid generation, target detection and identification and the like.