Accurate and fast calculation for dielectric-coated PEC surfaces with thin dielectric approximations

To calculate the scattering from thin dielectric-coated perfect electric conductor (PEC) surfaces, the impedance boundary conditions (IBC) and thin dielectric sheet (TDS) approximation are quite powerful in integral equation method because both remove the need to solve the field in dielectric layer. However, the rigid validation criteria restrict the application scope of IBC method. Although the TDS approximation removes physical restrictions by basing on the rigorous integral formulation, only electric material coating have been considered in available literatures. This paper gives an introduction of our progress in the calculation for dielectric-coated PEC surfaces with thin dielectric approximation, including the hybrid PEC-dielectric formulations to deal with the coating with electric and magnetic materials; the multi-layer TDS approximation to analyze coatings with relatively large thickness; the utilization of phase extracted basis functions for electrically large and smooth PEC coatings and some special treatments near the edges to account for the singularity currents for open PEC surfaces.