A GTD Solution to Scattering of Plane Waves at Oblique Incidence by a Dielectric Coated Circular Cylinder.

The problem of scattering of plane waves at oblique incidence on a dielectric coated conducting circular cylinder is studied. The eigenfunction series solution is developed from the boundary conditions where it becomes necessary to introduce a coupled part of the field. The eigenfunction series solution is then changed into a residue series solution for the shadow region via Watsons Transformation. Since the residue series solution is valid only in the shadow region, the physical optics approximation was evaluated asymptotically to obtain the geometrical optics solution in the lit region. Combining the residue series and the geometrical optics solution yields a solution compatible with the Geometric Theory Diffraction GTD. In carrying out Watsons Transformation it is seen that the coupled field is still present in the residue series solution while the geometrical optics solution remains uncoupled in the lit region.