Electromagnetic Wave Propagation and Scattering in a Randomly-Inhomogeneous Dielectric Sphere

摘要

Electromagnetic wave propagation and scattering in a sphere composed of an inhomogeneous medium having random variations in its permittivity are studied by using the Born approximation in solving the vector wave equation. The variations in the permittivity are taken to be isotropic and homogeneous, and are spatially characterized by a Gaussian correlation function. Temporal variations in the medium are not considered. Two particular problems are considered: (1) finding the far-zone electric field when an electric or magnetic dipole is situated at the center of the sphere, and (2) finding the electric field at the sphere's center when a linearly polarized plane wave is incident upon it. Expressions are obtained for the mean-square magnitudes of the scattered field components; it is found that the mean of the product of any two transverse components vanishes. The cases where the wavelength is much shorter than correlation distance of the medium and where it is much longer than it are both considered. (Author)