Design and Full Wave Green’s Function Analysis of Two Layer Hemispherical DRA

A Two layer hemispherical dielectric resonator antenna (HDRA) fed by a coaxial probe is rigorously analyzed here. The method of moment technique and Green’s function is used to obtain the probe current from which the input impedance of the DRA is calculated. The magnetic frill source model is considered. The piecewise sinusoidal (PWS) expansion mode is used and the results are compared. The Dielectric layers Permittivites and layer thickness between the outer and inner hemisphere are optimized for broadband operation of the coaxial probe fed DRA. Frequency tuning of the antenna structure is demonstrated, which maintains the broadband characteristics. Probe location (centered and offset) and length of the coaxial probe are optimized to obtain better impedance bandwidth and stable radiation pattern. The radiation characteristic of the antenna is also investigated in this research work. Simulations were carried out using HFSS v12.0 and it is observed that better impedance bandwidth and stable radiation pattern are obtained across the frequency range between 4–11 GHz.