Circularly polarized monopole antenna with bandwidth enhancement

A circularly polarized monopole antenna with bandwidth enhancement is presented. The circularly polarized characteristic is achieved by a C-shaped monopole. To enhance the bandwidth of the antenna, a rectangle stub is adopted on the ground. Simulated and measured results show that the antenna can operate at 3.5 GHz band. The impedance bandwidth and axial ratio bandwidth are 44.4% and 29.1%, respectively. Also, good radiation performance has been achieved.