Pattern-Reconfigurable Cylindrical Dielectric Resonator Antenna Based on Parasitic Elements

A novel pattern-reconfigurable cylindrical dielectric resonator antenna is presented. By the incorporation of four p-i-n diode switches and four parasitic elements, the mode of dielectric resonator excited by the probe changed. The antenna's radiation patterns can be shaped to concentrate energy in four specific directions, while minimizing the gain in other unwanted directions without affecting the impedance bandwidth of the antenna for its complete symmetry in structure. The antenna switches its radiation patterns among four reconfigurable modes with orthogonal directions at azimuth plane covering a bandwidth of several 870 MHz and exhibiting a high maximum gain of 9.74 dBi. A fully functional prototype has been designed, fabricated, and tested. The measured results of the reflection coefficient, radiation patterns, and realized gain verify the effectiveness of the proposed pattern switching concept for cylindrical dielectric resonator antenna. These capabilities make the antenna suitable for smart wireless devices in next generation communication systems as it can enhance the radio frequency front-end flexibility and performance by adding pattern diversity, especially for muti-input-muti-output systems in multipath environments.