A broadband circularly polarized cross-dipole antenna for GNSS applications

A broadband circularly polarized (CP) cross-dipole antenna is proposed for GNSS applications. The antenna has a very simple structure and a small size but has a very broad impedance bandwidth from 1.15 to 1.75 GHz (a fractional bandwidth of 41.4%) for S11 <; -10 dB. The CP bandwidth is from 1.37 to 1.5 GHz for axial ratio <; 3 dB. A computer simulation is conducted to optimize its dimensions and predict its performance. The optimized antenna is fabricated and measured. The simulated and measured results are in good agreement and have demonstrated that the proposed antenna is indeed a very good candidate for GNSS applications.