Electromagnetic Scattering by an Inhomogeneous Gyroelectric Sphere Using Volume Integral Equation and Orthogonal Dini-Type Basis Functions

The electromagnetic scattering by an inhomogeneous gyroelectric sphere is studied in this work. The solution is constructed using the well-known electric field volume integral equation (EFVIE). The kernel that incorporates the Green´s function is expanded in spherical vector wave functions, and the unknown electric field and electric displacement is expanded in spherical vector wave functions using fully orthogonal Dini-type basis functions. The permittivity tensor of the spherical object supports a continuously varying radial inhomogeneity, while its permeability is that of free space. This approach allows a fully analytical computation of the unknown matrix coefficients in special cases of homogeneous permittivity tensors. The validation of our method is performed by comparisons with published results in the literature. New numerical results are given for various continuously varying permittivity tensors.