I. Introduction
The existing methods for solving this problem, as they are reported in [1], [2], [3], [4], [5], are mainly based on numerical techniques. For instance, in [1] the -matrix method was used, and in [2], [3], [4]– the numerical evaluation of the spheroidal wavefunctions was employed to solve the problem. In [5] the concept of the equiphase sphere was used by the authors to study the scattering by nonspherical dielectric particles, and they tested their technique for dielectric spheroids. However, analytical, closed-form solutions for dielectric spheroids do not exist in the literature. In the present work we construct an efficient method, based on a shape perturbation technique, to get analytical, closed-form expressions for the electromagnetic scattering by dielectric spheroids.