Reliability of 5.8 GHz short range links in vehicle-roadside communication

An important part of a traffic management system is the exchange of detailed and individual information to and from the vehicles. The individual communication between infrastructure and vehicles is carried out over roadside beacons with a short range and bidirectional data link. The range varies and depends essentially on the speed of the vehicles, the applied data rate and the offered services. The technical aspects and propagation conditions of a 5.8-GHz mobile channel are investigated by simulation and measurements. The reliability of the data link is considered in multipath fading environment. Field trials at two test sites show that a reliable and suitable data link can be realized, if improvements such as space and frequency diversity techniques are implemented.