The dielectric-coated conducting sphere-modal and near-field characteristics

Abstract

A modal analysis and neat-field study for a dielectric-coated conducting sphere excited by a delta function electric field source has been made. The structure can support an infinite number of modes theoretically. For equatorial excitation only odd order modes are excited, whereas for non-equatorial excitation both even and odd order modes are excited. The variation of the amplitude coefficients both internal and external exhibit a different nature of variation with respect to the various structure parameters for different modes. The field distributions both in the rand 0 directions for non-equatorial excitation show good agreement between theory and experiment for the strongest mode.