Novel designs for broadband and compact dielectric resonator antennas

A Dielectric Resonator Antenna (DRA) with rectangular cross section is very versatile as it provides two independent degrees of freedom. In this thesis, various excitation mechanisms for the rectangular DRA such as coaxial probe, microstrip slot, and direct microstrip feed are discussed and analyzed using High Frequency Structure Simulator (HFSS).

The concept of a small DRA with wideband operation in the 5-6 GHz frequency band is presented. Two new DRA configurations with U-slot and square spiral shaped slot that offer significant enhancements to parameters such as size and bandwidth are investigated.

A very low profile DRA (length-to-height ratio ~ 4) made up of a relatively low permittivity material with broadband performance in the 8-10 GHz band is presented. Furthermore, the effect of a metallic patch on the resonant frequency and bandwidth of the low profile DRA is investigated. A modified microstrip feed is used to excite the DRAs.

The return loss, impedance characteristics and radiation patterns of the U-slot, square spiral-shaped slot, low profile and the compact DRAs are analyzed using Ansoft HFSS simulation software. The prototype and the test results for the low profile DRA and the compact DRA are discussed.