Circularly Polarized Metallic Post Integrated Patch Antenna for Road Transport and Traffic Telematics Application at 5.8 GHz DSRC Band

A left hand circularly polarized (LHCP) circular microstrip patch antenna (CMSA), operating at 5.8 GHz dedicated short range communication (DSRC) band using metallic posts (MPs) is explored in this paper for road transport and traffic telematics (RTTT) application. Optimal tuning of the distance between each pair of MPs a 176◦ wide axial ratio (AR) beamwidth for on-board unit (OBU) antenna is achieved. The OBU antenna offers a 18.5 dB cross-polarization isolation well-above the European standard (CEN-EN12253) for RTTT application. Analysis of the OBU integrated on a car model is also done to evaluate the effect of a large electromagnetic object on the antenna performance. The OBU antenna integrated on a vehicle offers a considerably high gain of 10.4 dBic with the 3 dB AR beamwidth of 298◦ and 236◦ in E-plane and H-plane, respectively.