An acceleration iteration technique for the electromagnetic scattering from objects above a rough surface

A hybrid analytic-numerical method combining the analytic physical optics (PO) and the numerical multilevel fast multipole algorithm (MLFMA) is applied in this paper to solve the electromagnetic scattering problem from the objects above a rough surface, where the PO and MLFMA are used to calculate the electromagnetic scattering of the rough surfaces and the object, respectively. In order to take the interaction effects among the rough surface into account, an iterative PO is introduced to improve the accuracy of tangent-plane approximation. Meanwhile, the fast far-field approximation (FAFFA) for the hybrid method is applied to speed up the electromagnetic iterative process between the two objects. Compared with the conventional method, the above treatments are very efficient to analyze this kind of scattering problem, especially for the Monte Carlo simulations in the random rough surface.