A novel center-fed dual-band circularly polarized antenna for GNSS applications

A novel center-fed Global Navigation Satellite System (GNSS) antenna is proposed in this paper. The antenna is composed of two layers of microstrip patches, a folded ground plane and three choke rings. Simulated and measured results show that two frequency bands for return loss >10 dB cover GPS L2 (1.193~1.247 GHz) and GPS L1 (1.545~1.625 GHz) with good axial ratio (AR) performance. The radiation patterns with AR<;3 dB cover the whole half upper space and the forward to backward ratio (FBR) is higher than 30 dB in the operating bands. The antenna is suitable for GNSS applications.