A New Wideband Circularly Polarized Stair-Shaped Dielectric Resonator Antenna

A circularly polarized stair-shaped dielectric resonator antenna (DRA) with a wideband circular polarization (CP) radiation is introduced for wireless local area network (WLAN) applications. This antenna is implemented by using two rectangular dielectric resonators (DRs), which are joined together to form a stair-shaped dielectric resonator antenna (DRA). In this structure, the excitation of multiple orthogonal modes leads to a wideband CP bandwidth. Measured results show that the proposed antenna has an axial ratio (AR) bandwidth of 22% (5.2–6.5 GHz), an impedance bandwidth of 37% (4.6–6.7 GHz), and a peak gain of 5.7 dB. In addition, the antenna radiation efficiency of more than 90% is achieved.