EM Diffraction by a Resistive Strip Attached to an Impedance Wedge

Abstract

The high frequency electromagnetic diffraction by a finite length resistive strip attached to a wedge with equal impedance faces is presented. The problem considered is two dimensional where the incident field is a plane wave polarized TM or TE to the axis of the wedge. Since the scatterer has two points of diffraction, the original problem can be first broken up into two simpler canonical problems which, due to the symmetry of the scatterer, can be obtained by a proper combination of special cases of the well known Maliuzhinets impedance wedge solution. A uniform asymptotic solution of these two canonical problems is developed which is continuous across the various shadow boundaries. This analysis also takes into account interactions between the two points of diffraction and points of reflection up to third order where spectral techniques are used to obtain the fields which are multiply diffracted and reflected as well as transmitted across the resistive strip. Incorporating these higher order interactions enhances the accuracy of the solution. Several numerical results are presented including comparisons with an independent moment method solution.