Safety Distance Calculation for Collision Avoidance in Vehicular Ad hoc Networks

A Vehicular Ad-Hoc Network (VANET) is a special form of Mobile ad-hoc network used for the communication between nearby vehicles and between vehicles and fixed roadside equipment. VANETs are an important component of Intelligent Transport System (ITS) that combines computer and communication technologies for traffic management to reduce traffic congestion, improve traffic efficiency, avoid accidents and improve road safety. Vehicular safety is an important application of VANET and these include vehicle collision warning, brake warning from a preceding car, obstacle warning and other emergency notifications. In this paper, we focus on accident prevention and propose a Safety Distance Calculation methodology that is based on the relative velocity and distance between the vehicles. The driver is warned, when the safety distance to another vehicle is reached so that the driver can take appropriate steps for collision avoidance. The proposed system is based on the positional information provided by GPS receivers. As most cars, today, are equipped with GPS receivers, our proposed system provides a simple and feasible solution for accident prevention. Since, the relative distance between the vehicles is used for computation; the safety distance can be accurately estimated.