Scattering by a composite wedge of metal and dielectric

Abstract

Summary form only given. In an analysis of the diffraction by an arbitrary-angled dielectric wedge Kim, Ra, and Shin (1991) formulated two sets of dual integral equations in the spectral domain, one inside the dielectric and the other outside the dielectric. The physical optics (PO) solution is obtained by using the two-dimensional Green's theorem for the geometrical optical (GO) contributions along the dielectric interfaces. The PO solution gives the reflected and the refracted GO fields, and the edge diffracted fields. The edge diffracted fields of the PO solution are asymptotically two cylindrical waves emanating from the edge, one valid inside the wedge v/sub 2/ and the other valid outside the wedge v/sub 1/. Substituting the physical optics solution plus unknown correction field, which makes the exact field solution, into the dual integral equation, one obtains the relation between the correction field and two edge diffracted fields of PO. It turns out that if one finds the nonuniform currents along tile dielectric interfaces that produce a field v/sub 1/ inside and -v/sub 2/ outside the region of the wedge with a background medium of free space and a dielectric, respectively, they give the correction fields. One may apply this method of dual integral equations to the scattering of electromagnetic waves by a composite wedge of metal and dielectric.