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

Highlights: • A wideband antenna was designed and studied both theoretically and experimentally. • Systematic analysis was performed to optimize sector angular size and permittivity. • Maximum impedance bandwidth was observed when the sector size was kept at 90°. • Multi-permittivity cylindrical resonator was fabricated from MgTiO₃–CoTiO₃ ceramics. • Impedance bandwidth up to 56% with stable broadside radiation pattern was achieved. - Abstract: 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° 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 °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 (θ) of 27.5° 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.