A survey on the extension of the UTD to the analysis of inhomogeneous plane wave diffraction

An overview of the work performed to extend the Uniform Geometrical Theory of Diffraction (UTD) to the analysis of inhomogeneous plane wave diffraction by a wedge is presented in this paper. The work was done in collaboration between the staff of the Microwave and Radiation Laboratory, Department of Information Engineering, University of Pisa and Prof. Robert G. Kouyoumjian, ElectroScience Laboratory, Ohio State University. We introduce first the two-dimensional solution for the scattering of inhomogeneous plane waves by a perfectly conducting wedge in a lossless medium. The above solution is then extended to account for dissipative losses in the medium surrounding the wedge, when also the wedge faces may be characterized by different surface impedances. Suitable expressions for the fields are also found in the more general three-dimensional case, for arbitrary polarization. The final objective is to apply these UTD solutions for calculating electromagnetic scattering from polygonal cylinders buried in lossy media.