Research On 3D Electromagnetic Scattering Modeling Based On Analytic Physical Optics And Feature Extraction Method

The target exhibits obvious scattering center characteristics in the high frequency region,and the feature extraction of the target scattering center provides strong support for radar image interpretation and target classification and recognition.The feature extraction method based on the electromagnetic scattering parametric model can effectively extract the features reflecting the target physical properties and electromagnetic scattering characteristics from the target echo data.In this paper,based on the analytic physical optics to construct the slab and spatially separated dihedral structure electromagnetic scattering parametric model,the influence of target spacing on the target scattering center feature extraction is studied,and a new idea of feature extraction is proposed.The establishment of the target electromagnetic scattering parametric model is the basis for the feature extraction of the target scattering center.In this paper,the spatially separated dihedral structure is extracted from the typical spatial target.Based on the validity of the analytic physical optics method using rectangular flat-plate structure verification,the analytic physical optics and geometric optics are combined to establish the three-dimensional bistatic electromagnetic scattering parametric model of separated dihedral.The experiment results show that the established parametric model achieves similar computational accuracy with the numerical simulation algorithm of electromagnetic simulation software and greatly improves the computational efficiency.Scattering center feature extraction based on parametric model is a kind of parameter estimation problem.Based on the accurate parameterization model of rectangular plate and spatially separated dihedral structure,the maximum likelihood estimation method based on decoupling in image domain is used to study the influence of target spacing on the scattering center feature extraction.A new idea of feature extraction is proposed.The parameter initialization and parameter optimization are performed by the scattering center image domain response and the frequency domain response respectively,and the effectiveness of the feature extraction method is verified.