A review of the recent advances in dielectric resonator antennas

This paper presents a comprehensive review of the state of art techniques and geometries which have been explored in the areas of Dielectric Resonator Antennas (DRA). With the evolution of first rectangular geometry to the current investigations, the basic aims of research in this field of electrical size miniaturization, retrofitting bandwidth as per commercial needs and radiation pattern stability by controlling the modes in the DRA still persist. Various techniques to miniaturize the physical and electrical size, mode excitation through varied mechanisms like probe, microstrip, slot, etc., improving bandwidth and radiation characteristics by various researchers have been included. The novel geometries and concept of fractals as introduced to the DRAs have also been addressed in this paper.