Comparison of Assisted and Unassisted Cooperative Collision Avoidance Distances at Intersections

Excess path loss due to obstruction by building corners at road intersections in urban and suburban areas (and the consequent loss of connectivity between vehicles or vehicles and infrastructure) limits the performance of vehicular ad hoc networks, especially those used to implement cooperative collision avoidance systems and emergency vehicle alert systems that warn drivers of oncoming traffic on cross streets. In recent years, researchers have developed simplified models of the excess path loss due to propagation around intersection corners that are useful in the simulation of vehicular ad hoc networks in suburban and urban environments. However, the geometry of actual intersections often exhibit a great deal more complexity than the simplified or idealized versions that form the basis for such existing excess path loss models. Here, we use ray-tracing simulations based upon accurate renderings of thirty-five intersections in and around urban and suburban areas of Vancouver, BC. to assess the accuracy of commonly used closed- form corner propagation models and compare the performance of assisted and unassisted cooperative collision avoidance systems.