Stacked Conical-Cylindrical Hybrid Dielectric Resonator Antenna for Improved Ultrawide Bandwidth

Conical and cylindrical dielectric resonator elements are vertically stacked and excited by a simple coaxial monopole. Compared to all earlier configurations, the proposed geometry significantly improves the impedance bandwidth. The ultrawideband response is enhanced due to the multiple resonances occurring by the suggested hybrid antenna. The footprint area of the antenna is only 63.6 mm(2) or 25.44 x 10(-3) lambda(2)(o) at the lowest operating frequency. The performance of the antenna is verified experimentally and numerically. Presented results show that the proposed hybrid monopole-DRA has a measured impedance bandwidth up to 148.6% (S-11 < -10 dB) along with consistent monopole-like radiation patterns and peak gain of 7.14 dBi. With such properties, the proposed hybrid monopole-DRA can be used in different ultra-wideband wireless applications and as wideband electromagnetic interference (EMI) sensors.