UAPO Solution for the Plane Wave Diffraction by a 90° Coated Wedge

This paper provides an alternative solution to the diffraction problem associated to a plane wave incident on a perfectly conducting wedge coated by dielectric layers. The skew incidence with respect to the edge of a right-angled structure is considered. The proposed analytical approach starts by considering the scattering integral and using a physical optics approximation of the electric and magnetic equivalent surface currents located on the external faces of the coated wedge. Useful approximations and analytical calculations allow one to apply a uniform asymptotic evaluation to the resulting integrals to obtain the diffraction coefficients. They are easy to handle and able to compensate the geometrical optics discontinuities.

1. Introduction

The canonical diffraction problem tackled in this manuscript refers to a uniform plane wave impacting on a perfectly conducting (PEC) wedge coated by dielectric layers. Such a problem is well known in literature and many methods have been proposed to solve it for a limited number of cases. The interest is justified by its occurrence in many application areas such as radar detection and wave propagation analysis in man-made environments.