Flexible Circularly Polarized Antenna for LTE-V2X/5G Vehicular Safety Applications

A circularly polarized wideband antenna for wireless and vehicle-to-everything (V2X) applications is presented in this work. Investigations are carried out on connected vehicles for road safety applications in the 3.4 GHz to 3.8 GHz frequency band. The chosen band facilitates wide-area connectivity and reduces the propagation effects at the 5.9 GHz dedicated short-range communication (DSRC) band. Supporting rising media like stream video and other V2N applications, the 5G services in the 3.4 GHz - 3.8 GHz licensed band is a crucial requirement. This work concentrates on the design of two CPW fed flexible circularly polarized antennas to operate in the frequency range of 2 GHz to 5 GHz to cover 3.4 GHz - 3.8 GHz and LTE 2600 MHz (Uplink: 2500 MHz - 2570 MHz and Downlink: 2620 MHz - 2690 MHz) frequency bands. Here cylindrical curvature is considered to place the antenna structure. Polyimide material is selected for the fabrication of antenna models. The effect of curvature on performance metrics such as S11, axial ratio, and gain is studied here. The experimented results are in close agreement with simulation results. The antenna structure is simulated in a virtual vehicular environment using the Ansys Savant SBR technique. The antenna is placed on the vehicle rooftop and side-view mirror positions to study the antenna far-field patterns in the vehicular applications. From the results, the designed circularly polarized antennas cover 2.5 GHz - 2.57 GHz and 2.62-2.69 GHz and 3.4 GHz - 3.8 GHz bands with sufficient gain (more than 3.2 dB).