Iterative Hybrid Method for Electromagnetic Scattering from a 3-D Object Above a 2-D Random Dielectric Rough Surface

An iterative hybrid method combining the Kirchhofi approximation (KA) and the multilevel fast multipole algorithm (MLFMA) is studied for electromagnetic scattering from a three- dimensional (3-D) object above a two-dimensional (2-D) random dielectric rough surface. In order to reduce the computational costs, some treatments have been studied. Firstly, the fast far-fleld approximation (FAFFA) is utilized to speed up the electromagnetic coupling interaction process between the rough surface and the object. Secondly, based on the scattering mechanism of the rough surface, a truncation rule on moderate rough surface for bi-static scattering is proposed under the plane wave illumination, which can further speed up the iteration. Compared with the conventional methods, the hybrid method with the above treatments is very e-cient to analyze the scattering of a 3-D object above random rough surfaces. Simulation results validate the efiectiveness and accuracy of the iterative hybrid method.