Full wave analysis of electromagnetic wave scattering from an imperfectly conducting cicular disc

Scattering from an imperfectly conducting circular disc of small thickness embedded in a homogeneous host medium is considered. The main feature of th e solution is the expansion of the unknown current distribution on the disc in terms of a complete set of orthogonal modal vector functions. The scatt ered electric field tangential to the disc is obtained as a single integrat ion over a spectral wavenumber. For a given exciting field, a procedure is outlined to obtain the amplitude of the vector wave functions representing the disc induced currents; consequently the scattered fields. A numerical e xample demonstrates the fast convergence of the modal current series. The s pecial case of excitation by a plane wave is treated in detail. The analysi s is relevant to mine detection within the earth.