Analysis of a Dielectric Resonator Antenna by Applying a Combined Semi-Analytical Method and Simulation

Abstract

The radiation properties of a hemispherical dielectric resonator, consisting of a monopole antenna placed in a dielectric hemisphere is theoretically examined. A method based on the combination of Green's function theory, in conjunction with the Method of Auxiliary Sources (MAS), is used to solve analytically and calculate the electromagnetic field at any arbitrary point of the structure. The Green's function theory is used to calculate the response of the hemisphere to an excitation consisting of an elementary dipole placed inside its volume. The Method of Auxiliary Sources (MAS) is applied by distributing a set of elementary dipoles along the axis of the antenna probe. A number of matching points, lying on the surface of the cylindrical antenna, are used to calculate the dipole moments of the auxiliary sources, by imposing appropriate boundary conditions. Additionally, the input impedance and the current distribution on the antenna are also derived through application of the above-mentioned methodology. The numerical results are finally validated by comparing them with the simulation results of the relevant configuration elicited using a commercial simulation FEM tool.