An Endfire Circularly Polarized Antenna for GNSS Mobile Phone Application

An endfire circularly polarized antenna for global navigation satellite system (GNSS) mobile phone applications is presented. The structure combines an inverted-F antenna (IFA) etched on the metal frame of mobile phone with a coupled-mode substrate integrated waveguide (CPSIW) cavity antenna on the back cover. The two radiators can generate dual orthogonal linear polarizations, respectively. The cavity antenna is directly fed by a probe, while the IFA is parasitically coupled. Righthand circularly polarized (RHCP) wave towards the endfire direction of the chassis ground plane is achieved by properly changing the distance between the two radiators. The proposed antenna achieves a -6dB bandwidth of 600MHz (1.55GHz to 1.61GHz). In the vicinity of the endfire direction, the GainRHCP is greater than 0 dBiC.