Integral theory of diffraction for material junctions

Abstract

A new approach to the scattering problem of waves by junctions is developed with the aid of the modified theory of physical optics (MTPO). The relation between the fundamental MTPO integral and the Fresnel function is given as a theorem with its proof. Then the integrals relation with the geometrical optics (GO) and diffracted waves is put forth with a theorem on the uniform asymptotic evaluation of scattering integrals. A new definition is introduced for the scattering process and it is shown that the solutions of some problems, related with material half-planes and junctions can be obtained easily by only evaluating the GO fields according to the new definition of the scattering phenomenon. The scattered and diffracted fields can be derived directly in terms of the MTPO integrals as a result of the relation between the GO and scattered waves. The resultant diffracted field expressions are investigated numerically.