Scattering from impedance objects at the edge of a perfectly conducting wedge

Abstract

In this study, scattering from impedance bodies positioned at the edge of a perfectly conducting (PEC) wedge is investigated. In the treatment of the problem, eigenfunction expansion in terms of spherical vector wave functions is employed. A complete dyadic Green’s function for the spherical impedance boss at the edge is developed and through decomposing the dyadic Green’s function, it can be observed that the contribution of the scatterer is separated from the wedge. It is shown that the scattering is highly enhanced by the edge guided waves. For the general case of irregularly shaped scatterer the solution is extended using T-matrix method. The method is implemented by replacing free space Green’s function with the dyadic Green’s function of the PEC wedge. The solution is verified by applying it to the case of spherical scatterer and results are compared with the dyadic Green’s function solution. The T-matrix solution is generalized for the multiple scatterer case. Numerical results are obtained for two impedance scatterers at the edge and compared with the PEC case.