The fast methods of high-frequency wave scattering in complex media and structures

Abstract

In this review work, we give a review of recent works of high-frequency electromagnetic (EM) wave scattering in complex media and structures. The EM wave scattering from electrically large scatterers remains an important and challenging problem. We introduce the quadratic patches to discretize the electrically large scatterers and present the fast physical optics (FPO) method to solve the PO radiation integral. The computational workload and accuracies of the physical optics (PO) scattered fields from the quadratic patches are error-controllable and frequency-independent, respectively. To remedy the limitations of the accuracies of the PO scattered fields in the lit region of the electrically large scatterers, we consider the Fock current from the convex scatterers to cover the contributions of creeping wave fields in the shadow region. For the coated material from the perfectly conducting structure, we propose the multi-level technique together with the PO method to calculate the scattered field in an efficient way. In the process of mesh discretization for electrically large scatterers, we adopt the quadratic patches and further extend them to adaptive patches. For the multi-scale scatterers, we use the hybrid method of moment and FPO (MoM-FPO) method to calculate the scattered field from the multi-scale scatterers.