Radiation pattern computation of a spherical lens using Mie series

The radiation pattern of a sphericai layered dielectric lens is computed using eigenfunction expansions. The method is an adaptation of the well-known classical solution for plane wave scattering from a layered sphere but uses the less well-known vector addition theorem for spherical wave functions to represent the off-center sources. The usefulness of this formulation is that the solution is analytical and "exact," and is an efficient tool for investigating spherical lens radiation properties. The method is illustrated for a typical Luneburg lens.