Diffraction of Plane Waves by Arbitrary-Angled Coated Wedges

Abstract

This research work deals with the plane wave diffraction by a coated perfect electrically conducting wedge with arbitrary apex angle. The uniform layer covering the impenetrable wedge is made of a standard double positive material or an unfamiliar double negative metamaterial with negative permittivity and permeability at the operating frequencies. The propagation mechanism is studied when the incidence direction is perpendicular to the edge of the composite structure, and uniform asymptotic solutions are proposed to evaluate the diffraction contribution for both the polarizations. Such approximate solutions are obtained by using the Uniform Asymptotic Physical Optics approach based on electric and magnetic equivalent surface currents radiating in the neighboring free space. The related expressions are user-friendly and provide reliable field values as verified by numerical tests involving a full-wave electromagnetic solver.