PLANE-WAVE DIFFRACTION BY A 2-PART IMPEDANCE STRIP

A uniform asymptotic high-frequency solution Is developed for the diff raction of (E-polarised) electromagnetic plane waves by a two-part imp edance strip. Uniform expressions for the interactions up to third ord er between the edges of the strip, including the conversion of surface -wave fields into space-wave fields, and vice-versa, via edge or junct ion diffraction, are obtained. The solution is based on a spectral ite ration technique consisting of taking the spectral representation of t he n-tuply diffracted field by one edge as the incident field for a ha lf-plane (or a two-part plane) associated with the other edge (or junc tion) where the (n + 1)th diffraction will take place. The analysis is then performed through the Wiener-Hopf technique for the (n + 1)th di ffraction. Bistatic diffraction patterns are obtained for different va lues of the surface impedances of the strip.