Thin dielectric sheet simulation by surface integral equation using modified RWG and pulse bases

The conventional thin dielectric sheet surface integral equation, proposed by Harrington and Mautz, is reviewed. Due to its simplicity and inadequency for certain problems, a new surface integral equation is proposed to fill the gap. This new formulation takes both tangential and normal currents into account so that it can handle problems with high and low permittivity and grazing incident waves. Based on the D-field formulation, inhomogeneity and surface charge can be treated correctly. Modelling the geometry by triangles, this surface integral equation is discretized and is suitable for the method of moments to solve. Rao-Wilson-Glisson and pulse functions are employed simultaneously for basis and testing functions and so the moment solution has full descriptions of polarization current in the thin dielectric layer. Several examples are examined by both analytical and other published numerical methods. These results show excellent agreement and demonstrate the validity and effectiveness of this new integral equation.