含曲面介质结构复杂目标电磁散射计算的射线追踪方法

针对含曲面介质结构的电大复杂目标电磁散射计算问题, 提出一种基于平面元网格模型曲率重构与射线密度归一化概念相结合的快速射线追踪方法.该方法通过曲率重构计算复杂目标表面的主曲率半径, 考虑从光疏介质到光密介质和从光密介质到光疏介质时电磁波照射凹凸曲面所具有的不同扩散或聚焦效应, 并利用射线密度归一化计算射线追踪过程中每一根射线对总散射场的贡献.当射线与介质表面的碰撞点位于焦散处时, 通过引入功率追踪成功克服了传统几何射线管在焦散处的奇异性.仿真结果验证了该方法的正确性和高效性.

Ray tracing method for electromagnetic scattering computation from complex target with curved surface dielectric structure

A ray tracing method combining the curvature reconstruction of faceted model with the ray-density normalization (RDN) is presented for electromagnetic(EM) scattering computation from electrically large complex target with curved surface dielectric structure. This method calculates the principal radii of curvature by curvature reconstruction, considers the different divergence or convergence effect for convex or concave surface illuminated by EM waves from optically thin medium to optically dense medium and from optically dense medium to optically thin medium, and calculates the contribution of each ray to the total scattered field by using RDN. The method also overcomes the singularity of traditional ray tubes at caustics by introducing the power tracing when the impact point between the ray and the interface is located at caustics. Simulation results verify the accuracy and efficiency of the proposed method.