Diversity Performance of Benchmark Scenarios for Hidden Vehicle-to-X Antennas Underneath the Roof

Various benchmark scenarios at 5.9 GHz for Vehicle-to-Everything (V2X) antennas hidden underneath the roof of the car are investigated. Spatial micro-diversity combining techniques compensate to a great extent the worsening of performance by hiding the antennas underneath the chassis. The feasibility of a new hidden position underneath the back of the roof is investigated. It shows better performance than the system centered underneath the roof. It is also demonstrated that such diversity systems counteract the disturbing effects of random scenarios that occur in a trip, such as the presence of human bodies or roll down of the side windows. Simulations with high-frequency asymptotic methods show good agreement with measurements performed in an outdoor far-field test range.