A High-Gain Mushroom-Shaped Dielectric Resonator Antenna for Wideband Wireless Applications

A high-gain mushroom-shaped dielectric resonator (DR) antenna for wideband wireless applications, featuring 65% fractional bandwidth, is proposed. The antenna consists of a low-permittivity hollow cylindrical DR provided with a top-mount spherical cap lens and a metal reflector, excited by means of coaxial probes. Suitable shaping of lens and reflector yields high gain (exceeding 14 dBi) and limited back radiation. The proposed antenna features a broadside radiation diagram with stable radiation patterns and wideband impedance matching. Its potential applications include access points for indoor/outdoor wireless multimedia systems as well as satellite terminal receivers. CST Microwave Studio, implementing a full-wave locally conformal finite integration technique, is employed to design and characterize the antenna, while the singularity expansion method is adopted to express the antenna response to arbitrary excitation waveforms. The numerical results concerning the antenna parameters are found to be in good agreement with the experimental measurements performed on an antenna prototype.