Electromagnetic scattering and radiation involving dielectric objects

Abstract

The influence of dielectric objects on electromagnetic fields is an important consideration in many engineering problems. In some applications, the scattering from dielectric objects for a known incident field is of interest. In other situations where dielectric objects interact with radiators - such as biological tissue near a wireless transceiver or a dielectric loaded antenna - the resulting input impedance, far-field radiation and power absorption characteristics are important quantities to determine. In this work an integral equation approach is used to solve these problems for which the method of moments is applied to facilitate a numerical solution. A comprehensive computer program was developed that handles both scattering and radiation problems. With the computer program both dipole and superquadric loop antennas can be modeled which have any arbitrary relative location and orientation to dielectric bodies of interest. The implementation is verified by comparison with finite-difference time-domain results and available measured data for both a scattering and radiation problem involving dielectric objects. It is then used to study some diverse situations which would be difficult to handle with standard Cartesian grid finite-difference time-domain, including: monostatic radar cross section of a dielectric slab with various conductivities; dipole and superquadric loop radiators printed on a dielectric substrate; and loop antennas in close proximity to a model of the human head.