Modeling of resistive sheets in finite element solutions [EM scattering]

A variational formulation is presented for modeling a resistive card in the context of the finite-element method (FEM). To validate this formulation, results based on a physical modeling of the resistive sheet are also presented. In this case, the resistive sheet is equivalently replaced by a thin dielectric layer. The modeling of such a layer in the usual manner leads to larger and consequently inefficient linear systems, which is the primary reason for resorting to a mathematical modeling of the resistive sheet. Results based on the mathematical and physical modeling are presented in connection with the scattering by a metal-backed cavity in a ground plane. These are used to validate the proposed mathematical model