基于时域物理光学法的二维导体粗糙面电磁散射特性研究

In this paper, time-domain physical optics (TDPO) method is extended to investigate electromagnetic (EM) scattering from two-dimensional (2D) perfectly electrical conducting (PEC) rough surface in both time domain and frequency domain. The scheme requires relatively small amounts of computer memory and CPU time, and has advantage over the Kirchhoff Approximation (KA) method in obtaining transient response of rough surface by a program run. The 2D Gaussian randomly rough surface is generated by Monte Carlo method and then is partitioned into small triangle facets though the meshing preprocess. The accuracy of TDPO is validated by comparing the numerical results with those obtained by the KA method in both backward and specular directions. The transient response and its frequency distribution of radar cross section (RCS) from rough surface are shown, respectively. The scattering results from rough surface with different size in the specular direction are given. The influence of the root mean square height ( ) and correlation length ( ) on electromagnetic scattering from PEC rough surface are discussed in detail. Finally, the comparisons of backscattering results at different incident angles are presented and analyzed.