A Discontinuous Galerkin Self-Dual Integral Equation Method for Scattering From IBC Objects

A discontinuous Galerkin self-dual integral equation (DG-SDIE) method is presented for accurately calculating electromagnetic scattering from objects with impedance boundary condition (IBC) surfaces. The working mechanisms of each term in the DG-SDIE formulation are studied physically and numerically. Based on the mechanisms, we propose a new efficient nonsymmetric DG-SDIE formulation (NDG-SDIE) for IBC problems. A comprehensive study is made to compare the NDG-SDIE with the previous symmetric DG-SDIE (SDG-SDIE) and antisymmetric DG-SDIE (ADG-SDIE) extension formulations for IBC. Numerical results demonstrate that NDG-SDIE is more efficient than SDG-SDIE and ADG-SDIE while generally maintaining the similar accuracy. In addition, we show that the DG methods are more attractive than the standard SDIE due to its flexible performance on large complex multiscale objects.