Electromagnetic scattering by inhomogeneous dielectric bodies modeled by cubic elements

The electric field distribution in an axially symmetric inhomogeneous dielectric body illuminated by a homogeneous plane wave is investigated by using a generalized analytical technique. The problem is formulated through the dyadic Green's function technique and solved by using the Method of Moments (MoM), which models an arbitrarily shaped dielectric body in terms of cubic elements. The singularity appearing in Green's functions is eliminated through a procedure which shapes the elements of MoM matrix into surface integrals that can be computed effectively. The numerical solutions are compared to analytical reference solutions for the special cases of homogeneous and concentric homogeneous spheres and the required size of the MoM matrix is observed to be quite small providing a rapid convergence. The convergence and the range of validity of the general analytical technique under consideration is tested for the first time for certain canonical problems of practical interest.