A Novel Low-Profile Dual Circularly Polarized Dielectric Resonator Antenna

A novel dual-port dual-sense circularly polarized (CP) T-shaped dielectric resonator antenna is introduced. The antenna consists of a T-shaped dielectric resonator, a pair of microstrip-fed stubs printed on a substrate with a truncated ground plane, and a decoupling network. Circular polarization is obtained by the structure to excite multiple orthogonal modes. The antenna can radiate left-hand CP (LHCP) or right-hand CP (RHCP) fields depending on the feed port selected. The measured RHCP (LHCP) field at the boresight direction is more than 26 dB (25 dB) stronger than the LHCP (RHCP) counterpart at the center operating frequency. The measured results show that the antenna has usable bandwidths of 17.2% (4.98-5.92 GHz) and 17.9% (5.02-6.03 GHz) and peak gains of 3.2 and 3.3 dBic at two feed ports, respectively. The isolations between two feed ports are better than 22.5 dB over the whole operating band. In addition, the antenna has peak radiation efficiencies of about 89% and 91% for Ports 1 and 2, respectively.