Circularly Polarized Antenna with Low Profile and High Gain

A low profile and high gain circularly polarized (CP) antenna is investigated in this paper. The CP antenna consists of two orthogonal metallic strips and periodic shorting slices on their edges. The strips are fed with 90-degree phase difference at the corner by a single coaxial probe to realize circular polarization. Then four metallic strips are arrayed in sequential rotation and fed by a compact 3/4 ring. The simulated 10-dB impedance bandwidth and 3-dB axial ratio bandwidth are 30.9% (6.76–9.23 GHz) and 18.8% (6.75–8.15 GHz), respectively. The CP antenna with a low profile of $\sim 0.06 \lambda_{0}$ has a peak gain of 13.3dBi.