Wideband planar monopole antenna with circular polarized radiation

The wideband circularly polarized planar monopole antenna that employs a wideband feeding network is presented in this paper. The proposed antenna is formed by four simple wideband planar monopole antenna elements in order to improve the performance of circular polarization. Also, it achieves simple structure in the wideband antenna with wideband feeding network. The attractive characteristics of the proposed antenna are the wide impedance bandwidth of 87.3% (1 GHz to 2.55 GHz), the 3 dB axial ratio bandwidth of 95% (1.05 GHz to 2.95 GHz), and the maximum gain within the 3 dB AR bandwidth is about 4 dBic. Moreover, the ground size is less than λ₀ × λ₀.