Near-Field Pattern Diffracted by a Spherical Cavity in a Denser Medium

Abstract

A copolarized electric field diffracted by a spherical cavity in a denser dielectric medium is analyzed in the forward near-field region when the wavelength is comparable to one half the cavity radius. It is shown that double nulls and dips exist in the measurement plane transverse to the propagating direction of the incident field, and their dependences on the frequency, the distance of the measurement plane, and the measurement angles are analyzed.