Fast Computation of Electromagnetic Scattering From a Metal–Dielectric Composite and Randomly Distributed BoRs Cluster

Abstract

An efficient equivalence principle algorithm with spherical equivalent source (SEPA) is proposed to analyze the electromagnetic scattering from a metal–dielectric composite and randomly distributed bodies of revolution (BoRs) cluster, which is called SEPA-CBoR for short. Due to the rotationally symmetrical property, the electromagnetic currents on the BoRs and the equivalence spheres (ESs) are all expanded by the basis functions of BoR. In this way, the self-action and the interaction can be both calculated by using the method of moment for BoR (BoR-MoM). With the repeatability fully used, the self-action for the BoRs with the same size just needs to be calculated once. Moreover, the interaction can also be got once when the size and relative displacement vector of their corresponding ESs are the same. Since these self-action/interaction matrices are constructed in mutually orthogonal Fourier modes, the entire problem is eventually solved by a couple of small matrix equations independently. As a result, the SEPA-CBoR method can greatly save the memory requirement and solution time. Several numerical examples are presented to demonstrate the accuracy and efficiency for the composite BoRs cluster problems. Especially, it is helpful to distinguish the fake targets with the accurate echo signs obtained from the efficient SEPA-CBoR method.