Analysis of a strip-grating twist reflector

Abstract

We present a rigorous analysis of scattering from a twist reflector composed of a strip grating placed on a dielectric slab and backed by a conducting metallic sheet. The obliquely incident, arbitrarily polarized plane wave is decomposed into fast- and slow-polarized modes, and a complete and accurate solution of the total diffracted fields is derived. The solution procedure used is an extension of our solution procedure developed for the analysis of scattering from a strip grating. We calculate the optimum height w, in order for the fast- and slow-polarized diffracted fields to be in phase, for various angles of incidence and different periods of the strip grating. With air as the dielectric between the strip grating and the ground plane, it is shown that a strip-grating twist polarizer behaves similarly to the corrugated-surface twist polarizer.