Broadband Circularly Polarized Patch Antenna Array for Vehicle Communication

A circularly polarized (CP) antenna which is a set of 2×2 patch array with parasitic rectangular elements is designed and measured. The parasitic patch can enhanced the gain of the antenna. Each antenna element is fed by two probe that is connected to the feeding network. The final design, with an overall size of 160mm×160mm×28mm ( ~ 1.1λ0×1.1λ0×0.2λ0 at 2.09 GHz), was fabricated and measured. The proposed antenna has been fabricated and measured. The antenna array has a measured dB bandwidth of 1.82-2.4 GHz(27.5%), the 3-dB axial-ratio(AR) bandwidth of 1.9-2.2 GHz is also obtained. Besides, the peak gain of the antenna array is 13.46 dBi at 2.01 GHz.