On-Glass Grid Structure and Its Application in Highly-Transparent Antenna for Internet of Vehicles

In this paper, a low-cost printed-circuit-board (PCB) technology-based on-glass grid structure and its application in highly-transparent antenna for the internet of vehicles are presented. Firstly, a diamond-shaped grid structure on a glass substrate for high optical transparency (OT) is studied. To show the feasibility, two equal-length co-planar waveguide (CPW) transmission lines (TMLs) with conventional solid and the proposed grid structure are compared. It is found that identical electrical length and comparable performance of the two TMLs are obtained. The relationship between OT and electrical performance is also derived. In the next place, the application of the on-glass grid structure in the highly-transparent antenna design is explored, and the detailed fabrication process is presented. Finally, for demonstration, a CPW-fed wideband end-fire on-glass highly-transparent antenna covering the 5.8-GHz vehicle-to-vehicle band is designed, fabricated, and measured. Ultra-broad impedance bandwidth of 64.6% (3.08–6.02 GHz), wide H-plane beamwidths of over 146°, high antenna efficiencies of over 71.9%, and high OT of 69.8% are achieved. Easily fabricated with mature PCB technology and integrated on the vehicle windows, the proposed structure provides a low-cost highly-transparent solution for the internet of vehicles.