Singular Integral Equation Approach to Plane Wave Diffraction by an Infinite Strip Grating at Oblique Incidence

Abstract

An accurate numerical solution of the plane wave diffraction by an infinite strip grating is presented, where the incident wave propagates in an arbitrary direction and is arbitrarily polarized. We derive a set of singular integral equations and solve it by the moment method, where the Chebyshev polynomials are chosen for the basis and the testing functions. The edge condition is incorporated in the expansion of the unknown functions in order to accelerate the convergence. A decomposition of the kernel into a singular and a regular part enables us to avoid the relative convergence phenomenon. Numerical results show the accuracy of the present method. Some numerical examples are presented for the polarization discrimination characteristics and surface current distributions.