Design of a novel dielectric resonator antenna using MgTiO3-CoTiO3 for wideband applications

In this work, a novel low profile design of a cylindrical dielectric resonator (DR) antenna with two different permittivity materials is proposed for wideband applications. The multi-permittivity cylindrical DR (MPCDR) was formed by combining four 90 degrees sectors whereby sectors with the same permittivity were positioned in opposite quadrants. Simulation of the antenna was performed in the time domain using computer simulation technology (CST 2014).A systematic analysis was carried out to optimize the antenna's sector size and permittivity. The prototype was fabricated using MgTiO3 (MTO) and CoTiO3 (CTO) dielectric materials prepared via solid state reaction. MTO and CTO were sintered at 950 degrees C (4 h) and subsequently analyzed by XRD to confirm the presence of a single phase. The dielectric properties of MTO and CTO were studied by electrical characterization; it was found that MTO and CTO have permittivity values of 15.72 and 9.85, respectively. The antenna performance was analyzed by placing the MPCDR on top of a microstrip line with an angular position (theta) of 27.5 degrees with respect to the longitudinal axis of the feed line An impedance bandwidth up to 56% with stable broadside radiation pattern was achieved in both the simulation and measured. (C) 2015 Elsevier Ltd. All rights reserved.