Abstract

In vehicular scenarios, particularly at urban intersections, the line of sight among connected vehicles is partially or totally affected by obstacles. This obstruction negatively impacts the ability of road safety systems based on vehicular communications to detect neighboring vehicles into the cross road from the intersection. Typically, these obstructions lead to communication degradation, due to the severe signal attenuation. In this paper, we propose an efficient and robust retransmission mechanism based on the distance of the vehicle to the intersection, increasing the probability of successful packets delivery, as well as the warning range and the corresponding notification time needed by road safety systems. We demonstrate that the proposed retransmission mechanism outperforms the classic retransmission mechanisms in terms of the required channel capacity, by reducing the channel's load in a 50% and a 30%, when the transmissions are originated in the nearest zones from the intersection.