Experimental Characterization of a Helical Antenna Integrated in the Rear of a Vehicle for C-V2X Communications

A helical antenna for Cellular-Vehicle To Everything (C-V2X) communications is manufactured and integrated around the car high mount stop light (CHMSL) area of a Ford SUV vehicle. The antenna performance is measured on a foam pillar, on a ground plane and on the vehicle, inside a near field measurement system. The antenna consists of three helical arms wrapped around a 3D-printed hemisphere with a radius of 4.8 mm. The helical arms are built using commercial wire with a radius of 0.127 mm. It operates in a monopole configuration, has an omni-directional radiation pattern and vertical polarization. The maximum measured realized gain of the antenna when integrated on the vehicle is 2.5 dBi at 5.9 GHz.