In recent years, there has been an increasing interest in the use of dielectric resonator (DR) structures as radiating antenna elements, and The University of Mississippi Department of Electrical Engineering has participated heavily in the development of models for the analysis of both the DR and DR antenna structures. This research has evolved out the faculty's research beginning in the early 1980's as related to simple, cylindrical DR elements made of high dielectric constant ceramics as shown in the accompanying figures. This research led to the publishing of the first definitive book on DIELECTRIC RESONATORS by Artech House in 1986 that has been reprinted by Vector Forum in 1990 and by Noble Publishing in 1998 in a Second Edition by Drs. Darko Kajfez and Pierre Guillon, editors, along with other faculty members from The University of Mississippi. The accompanying, line drawn figure shows an early version of Microstrip-fed DR antenna (reference "Input impedance of microstrip-slot-coupled DR antennas mounted on thin dielectric layers", by Junker, Kishk, Kajfez, Glisson and Guo, International Journal of Microwave and MM-Wave Computer-Aided Engineering, Vol. 6 No. 3, 174-182, 1996).

DRA Test Fixture

Dielectric Resonators

The DR antenna element has the potential to provide significant advantages in terms of size reduction, improved bandwidth, higher power handling capability, and increased efficiency as compared with the microstrip antennas (See accompanying figures). The current state of the art in the utilization of the DR antennas, however, is probably about where the utilization of the widely used microstrip antenna was about 30 years ago. However, with the advent of increased computational power and a better understanding of the DR antennas, advances have been made at an increasing rate recently.

DR antennas made from new ceramic materials with high dielectric constants and low loss are inherently smaller in size and they have greater operating bandwidths than microstrip antennas. Thus, they may be useful in a variety of personal and mobile communications systems, and other commercial and military systems over a wide range of frequencies.

DRA Radiation Pattern

Return Loss of DRA

The University of Mississippi DR antenna research group has developed a basic design and computer simulation for a dielectric resonator antenna element for implementation and testing of a small, phased array antenna. Research based on numerical simulation and measurements is ongoing to determine the characteristics of a wide variety of DR antenna shapes elements to for a wide range of commercial and military applications.

At present, various element shapes are investigated for their suitability of generating the appropriate radiation patterns for linear or circular polarizations. Work related to measurement of the radiation efficiency of the dielectric resonator element has been initiated and is being pursued.