Refined target electromagnetic scattering characteristic calculation method based on measurement and calculation fusion

Abstract

The invention provides a refined target electromagnetic scattering characteristic calculation method based on measurement and calculation fusion, and the method comprises the steps: S1, building a corresponding target physical model for a target, and building a digital geometric model corresponding to the target physical model; s2, micro structures in the target physical model are analyzed and manually screened; s3, obtaining the electromagnetic current data of each screened micro structure, and rejecting the micro structure of which the corresponding electromagnetic current data is lower than the background noise; s4, searching a target surface element corresponding to the position of the micro structure, and establishing an association relationship between the micro structure and the corresponding target surface element; s5, performing electromagnetic scattering characteristic simulation on the target digital model to obtain electromagnetic current data of each target surface element, and updating the electromagnetic current data of the corresponding target surface element based on the electromagnetic current data of the micro structure; and S6, performing electromagnetic field integral operation on the electromagnetic current data of all the target surface elements to obtain a scattering field of the target.

Description

Technical Field

[0001] The present invention relates to the technical field of target characteristic simulation, and in particular to a method for calculating refined target electromagnetic scattering characteristics based on measurement and calculation fusion. Background Art

[0002] The refined target electromagnetic scattering characteristic modeling technology is one of the key technologies in the target and environment characteristic simulation technology. It can obtain accurate target characteristic data, analyze the target electromagnetic scattering hotspots, and support the design of low-scattering targets, target detection and recognition algorithms. At present, domestic and foreign experts and scholars have conducted a lot of research on the simulation algorithm of target electromagnetic scattering characteristics, forming theoretical methods covering high-frequency asymptotic method, full-wave numerical method, etc., and verifying the algorithm in combination with microwave darkroom testing, which has promoted the development of target characteristic simulation algorithm.

[0003] However, how to improve the accuracy of the target electromagnetic scattering characteristic data and enhance the confidence of the target characteristic simulation data is still a realistic challenge faced by experts and scholars today. At present, the common practice is to strengthen the research on the simulation algorithm of the target electromagnetic scattering characteristics and develop more accurate and efficient electromagnetic algorithms. Another method is to establish a geometric digital model that is closer to the target object and the target material is complete. Both of the above methods have shortcomings. The first method lacks research on the actual model of the target, and the second method is affected by the machine processing accuracy and modeling accuracy. It is difficult to achieve a digital model that is completely consistent with the physical model.

[0004] At present, in order to improve the accuracy of the simulation data of the target electromagnetic scattering characteristics, most of the focus is on the research of electromagnetic scattering simulation algorithms, but there is a lack of research on the input of simulation digital models. The consistency between the digital geometric model and the physical model is difficult to achieve due to objective conditions. Therefore, it is necessary to find a refined target electromagnetic scattering characteristic calculation method based on measurement and calculation fusion, combining the physical model with the simulation algorithm, fully considering the scattering contribution of the tiny structure in the target, obtaining more accurate target electromagnetic scattering characteristic data, and making the simulation of the target electromagnetic scattering characteristics more refined and accurate. Summary of the invention

[0005] The purpose of the present invention is to provide a method for calculating the electromagnetic scattering characteristics of a refined target based on measurement and calculation fusion, which separates the microstructure in the target physical model, uses a pre-test method to obtain the electromagnetic flow data of the microstructure, and uses it to update the electromagnetic flow data of the corresponding target surface element in the digital geometric model (corresponding to the target physical model), and performs electromagnetic field integration operation on the electromagnetic flow data of all target surface elements to obtain the scattering field of the target. The present invention can greatly improve the accuracy and precision of modeling in the modeling of the electromagnetic scattering characteristics of the target.

[0006] In order to achieve the above object, the present invention provides a method for calculating the electromagnetic scattering characteristics of a refined target based on measurement and calculation fusion, comprising the steps of:

[0007] S1, establishing a corresponding target physical model for a target; establishing a digital geometric model corresponding to the target physical model; the digital geometric model includes a plurality of target surface elements;

[0008] S2, analyzing the microstructures in the target physical model and performing manual screening;

[0009] S3, obtaining the electromagnetic flow data of each of the screened microstructures, and discarding the microstructures whose corresponding electromagnetic flow data is lower than the background noise;

[0010] S4, searching for the target surface element corresponding to the location of the microstructure, and establishing an association relationship between the microstructure and the corresponding target surface element;

[0011] S5, simulating the electromagnetic scattering characteristics of the target digital model to obtain the electromagnetic flow data of each target surface element; updating the electromagnetic flow data of the corresponding target surface element based on the electromagnetic flow data of the microstructure;

[0012] S6. Perform electromagnetic field integration operation on the electromagnetic flow data of all target surface elements to obtain the scattering field of the target.

[0013] Optionally, step S1 includes: generating a corresponding mesh model for the target physical model by a laser three-dimensional scanning method; converting the mesh model into a corresponding solid model, importing the solid model into CAD software for model modification, and obtaining the digital geometric model.

[0014] Optionally, the model modification in step S1 includes: manually correcting areas of surface overlap, non-conformal edges, and vertex separation in the digital geometric model, and correcting the surface curvature of the digital geometric model according to the surface curvature of the target physical model.

[0015] Optionally, obtaining the screened electromagnetic flow data of the microstructure in step S3 includes:

[0016] S31, establishing a microstructure physical model corresponding to the microstructure;

[0017] S32. Perform microwave darkroom testing on the microstructure physical model at different frequency bands and different polarizations to obtain electromagnetic flow data of the microstructure physical model in the entire space and wide frequency band; the electromagnetic flow data of the microstructure physical model is used as the electromagnetic flow data of the microstructure.

[0018] Optionally, step S4 includes:

[0019] S41, numbering the microstructures; numbering each target surface element;

[0020] S42, searching for the target surface element corresponding to the location of the microstructure, and establishing a key-value pair based on the number of the microstructure and the number of the corresponding target surface element, with the number of the microstructure as the key and the number of the target surface element as the value.

[0021] Optionally, in step S5, a full-wave numerical algorithm is used to simulate electromagnetic scattering characteristics of the target digital model.

[0022] Optionally, updating the electromagnetic flow data corresponding to the target surface element includes: adding the electromagnetic flow data of the microstructure to the electromagnetic flow data of the corresponding target surface element, and using the result of the addition as the updated electromagnetic flow data of the corresponding target surface element.

[0023] Optionally, the microstructure includes at least one of a rivet and a gap.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The method for calculating the electromagnetic scattering characteristics of a refined target based on measurement and calculation fusion of the present invention obtains the electromagnetic flow data of each target surface element by simulating the electromagnetic scattering characteristics of the digital geometric model of the target. At the same time, the scattering contribution of the microstructure is fully considered, the microstructure in the target physical model is separated, and the electromagnetic flow data of the microstructure is obtained by pre-testing means, which is used to update the electromagnetic flow data of the corresponding target surface element. Finally, the scattering field of the target is obtained by performing electromagnetic field integration operations on the electromagnetic flow data of all target surface elements. Based on the idea of ​​measurement and calculation fusion, the present invention combines the target physical model with the corresponding digital geometric model, solves the problem that it is difficult to maintain consistency between the target physical model and the digital geometric model, and realizes the refined calculation of the target electromagnetic scattering characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings required for the description. Obviously, the drawings described below are an embodiment of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work:

[0027] Figure 1 The present invention is a flow chart of a method for calculating the electromagnetic scattering characteristics of a refined target based on measurement and calculation fusion. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] It should be understood that when used in this specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0030] It should also be understood that the terms used in this application specification are only for the purpose of describing specific embodiments and are not intended to limit the application. As used in this application specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0031] It should be further understood that the term “and / or” used in the specification and appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0032] As used in this specification and the appended claims, the term "if" may be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrases "if it is determined" or "if [described condition or event] is detected" may be interpreted as meaning "upon determination" or "in response to determining" or "upon detection of [described condition or event]" or "in response to detecting [described condition or event]," depending on the context.

[0033] In addition, in the description of the present application, the terms "first", "second", "third", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0034] This embodiment provides a method for calculating the electromagnetic scattering characteristics of a refined target based on measurement and calculation fusion. Figure 1 As shown, it includes the steps:

[0035] S1. Establishing a corresponding target physical model for the target; establishing a digital geometric model corresponding to the target physical model; the digital geometric model includes a plurality of target surface elements;

[0036] In this embodiment, a corresponding mesh model is generated for the target physical model by a laser three-dimensional scanning method, and then the mesh model is converted into a corresponding solid model, and the solid model is imported into CAD software for model modification to obtain the digital geometric model.

[0037] In this embodiment, the modification of the physical model includes: manually modifying the parts of the digital geometric model where the surfaces overlap, the edges are not conformal, and the vertices are separated, and modifying the surface curvature of the digital geometric model according to the surface curvature of the target physical model. After the modification, the target physical model is completely consistent with the digital geometric model except for the tiny structures in the target physical model. The tiny structures in this embodiment include at least one of rivets and gaps.

[0038] S2. Analyze the tiny structures in the target physical model and perform manual screening.

[0039] In this embodiment, tiny structures that have a greater impact on the scattering characteristics of the target are manually screened out, and a tiny structure set is established based on the screening results. For example, the tiny structures can be screened based on their sizes, and when the size of a tiny structure is larger than a preset size, it is determined to be a tiny structure that has a greater impact on the scattering characteristics of the target, and the tiny structure is placed in the tiny structure set.

[0040] S3, obtaining the electromagnetic flow data of each screened microstructure, and discarding the microstructure whose corresponding electromagnetic flow data is lower than the background noise;

[0041] The screened microstructures are microstructures in the microstructure set. In this embodiment, step S3 includes:

[0042] S31, establishing a microstructure physical model corresponding to the microstructure (in the microstructure set);

[0043] In a preferred embodiment, for microstructures with the same shape and size, it is sufficient to establish a physical model of the microstructure.

[0044] S32. Conduct microwave darkroom testing on the physical model of the microstructure at different frequency bands and different polarizations to obtain electromagnetic flow data of the physical model of the microstructure in the full space and wide frequency band; use the electromagnetic flow data of the physical model of the microstructure as the electromagnetic flow data of the corresponding microstructure.

[0045] S33. If the electromagnetic flow data of the tiny structure is lower than the background noise, the tiny structure is deleted from the tiny structure set.

[0046] S4, searching for a target surface element corresponding to the location of the microstructure, and establishing an association relationship between the microstructure and the corresponding target surface element;

[0047] In this embodiment, step S4 includes:

[0048] S41, numbering the microstructures in the microstructure set; numbering each target surface element;

[0049] S42. Search for the target surface element corresponding to the location of the microstructure, and establish a key-value pair based on the number of the microstructure and the number of the corresponding target surface element, in the form of <microstructure number, target surface element number>, with the microstructure number as the key and the target surface element number as the value.

[0050] S5, simulating the electromagnetic scattering characteristics of the target digital model to obtain the electromagnetic flow data of each target surface element; updating the electromagnetic flow data of the corresponding target surface element based on the electromagnetic flow data of the microstructure;

[0051] In this embodiment, a full-wave numerical algorithm is used to simulate the electromagnetic scattering characteristics of the target digital model (this is the prior art).

[0052] In this embodiment, the electromagnetic flow data of the microstructure and the electromagnetic flow data of the corresponding target surface bin are added, and the result of the addition operation is used as the updated electromagnetic flow data of the corresponding target surface bin.

[0053] The electromagnetic flow data includes current data and magnetic flow data.

[0054] Order I total represents the updated current data of the target surface element, I face represents the current data of the target surface element before updating, I micro represents the current data corresponding to the microstructure, then

[0055] I total =I face +I micro .

[0056] Let M total represents the updated magnetic flow data of the target surface element, M face represents the magnetic flow data of the target surface element before updating, M micro represents the magnetic flow data corresponding to the microstructure, then

[0057] M total =M face +M micro .

[0058] S6. Perform electromagnetic field integration operation on the electromagnetic flow data of all target surface elements to obtain the scattering field of the target (this is the prior art).

[0059] The method for calculating the electromagnetic scattering characteristics of a refined target based on measurement and calculation fusion of the present invention obtains the electromagnetic flow data of each target surface element by simulating the electromagnetic scattering characteristics of the digital geometric model of the target. At the same time, the scattering contribution of the microstructure is fully considered, the microstructure in the target physical model is separated, and the electromagnetic flow data of the microstructure is obtained by pre-testing means, which is used to update the electromagnetic flow data of the corresponding target surface element. Finally, the scattering field of the target is obtained by performing electromagnetic field integration operations on the electromagnetic flow data of all target surface elements. Based on the idea of ​​measurement and calculation fusion, the present invention combines the target physical model with the corresponding digital geometric model, solves the problem that it is difficult to maintain consistency between the target physical model and the digital geometric model, and realizes the refined calculation of the target electromagnetic scattering characteristics.

[0060] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0061] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for calculating the electromagnetic scattering characteristics of a refined target based on measurement and calculation fusion, characterized in that: Contains steps: S1, establishing a corresponding target physical model for a target; establishing a digital geometric model corresponding to the target physical model; the digital geometric model includes a plurality of target surface elements; S2, analyzing the microstructures in the target physical model and performing manual screening; S3, obtaining the electromagnetic flow data of each of the screened microstructures, and discarding the microstructures whose corresponding electromagnetic flow data is lower than the background noise; S4, searching for the target surface element corresponding to the location of the microstructure, and establishing an association relationship between the microstructure and the corresponding target surface element; S5, simulating the electromagnetic scattering characteristics of the target digital model to obtain the electromagnetic flow data of each target surface element; updating the electromagnetic flow data of the corresponding target surface element based on the electromagnetic flow data of the microstructure; S6. Perform electromagnetic field integration operation on the electromagnetic flow data of all target surface elements to obtain the scattering field of the target.

2. The method for calculating the electromagnetic scattering characteristics of a refined target based on measurement and calculation fusion according to claim 1, characterized in that: Step S1 includes: generating a corresponding mesh model for the target physical model by a laser three-dimensional scanning method; converting the mesh model into a corresponding solid model, importing the solid model into CAD software for model modification, and obtaining the digital geometric model.

3. The method for calculating the electromagnetic scattering characteristics of a refined target based on measurement and calculation fusion according to claim 2, characterized in that: The model modification in step S1 includes: manually correcting the parts of the digital geometric model where the surfaces overlap, the edges are not conformal, and the vertices are separated, and correcting the surface curvature of the digital geometric model according to the surface curvature of the target physical model.

4. The method for calculating the electromagnetic scattering characteristics of a refined target based on measurement and calculation fusion according to claim 1, characterized in that: The step S3 of obtaining the screened electromagnetic flow data of the microstructure includes: S31, establishing a microstructure physical model corresponding to the microstructure; S32. Perform microwave darkroom testing on the microstructure physical model at different frequency bands and different polarizations to obtain electromagnetic flow data of the microstructure physical model in the entire space and wide frequency band; the electromagnetic flow data of the microstructure physical model is used as the electromagnetic flow data of the microstructure.

5. The method for calculating the electromagnetic scattering characteristics of a refined target based on measurement and calculation fusion according to claim 1, characterized in that: Step S4 includes: S41, numbering the microstructures; numbering each target surface element; S42, searching for the target surface element corresponding to the location of the microstructure, and establishing a key-value pair based on the number of the microstructure and the number of the corresponding target surface element, with the number of the microstructure as the key and the number of the target surface element as the value.

6. The method for calculating the electromagnetic scattering characteristics of a refined target based on measurement and calculation fusion according to claim 1, characterized in that: In step S5, a full-wave numerical algorithm is used to simulate the electromagnetic scattering characteristics of the target digital model.

7. The method for calculating the electromagnetic scattering characteristics of a refined target based on measurement and calculation fusion according to claim 5, characterized in that: The updating of the electromagnetic flow data corresponding to the target surface element includes: performing a sum operation on the electromagnetic flow data of the microstructure and the electromagnetic flow data of the corresponding target surface element, and using the sum operation result as the updated electromagnetic flow data of the corresponding target surface element.

8. The method for calculating the electromagnetic scattering characteristics of a refined target based on measurement and calculation fusion according to claim 1, characterized in that: The microstructure includes at least one of a rivet and a gap.

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