Scattering from a conducting cylinder shielded with a dielectric bead

Modal theory of electromagnetics in combination with Fourier transform techniques are used to formulate a three-dimensional scattering problem. A perfectly conducting circular cylinder of infinite extent is shielded partially with a homogeneous dielectric bead. Exact interior eigenfunctions are utilized as whole-body expansion functions in the moment method formulation of the scattering problem. Exploiting the natural internal modes in the moment solution results in a significant reduction in the number of unknowns and ultimately a marked computational advantage. Numerical results pertaining to the interior EM fields and the convergence properties of the series expansions are presented. Effects of the dielectric coating on the backscattered field as well as bistatic scattering are also studied.