Hybridization of SBR and FEM for scattering by large bodies with cracks and cavities

A robust hybrid technique is presented for an evaluation of electromagnetic scattering by large bodies with cracks and cavities on their surfaces. This technique employs the shooting-and-bouncing-ray (SBR) method to compute the scattering from the large bodies with the cracks and cavities filled with perfect conductors and the finite-element method (FEM) to characterize the cracks and cavities whose openings are covered with perfect conductors. A coupling scheme is then developed to combine these two methods in such a manner that (i) it includes all significant interactions and (ii) it permits the SBR and FEM to be computed separately. This results in an efficient and accurate computation of the scattering by large bodies with cracks and cavities. Several numerical results are presented, demonstrating the accuracy, efficiency, and capability of the technique