Scattering from an object above a rough surface using the Extended PILE method hybridized with PO approximation

A new hybrid method which combines the E-PILE (Extended Propagation-Inside-Layer Expansion) method and the Physical Optics approximation (PO), is developed for computing the electromagnetic scattering from an object above a rough surface for a three-dimensional problem. Such a 3-D problem involves a large number of unknowns and can not be solved easily with a conventional method of moments (MoM) by using a direct LU inversion. Thus, a hybridization between the E-PILE and PO reduces significantly the memory requirements and CPU time.