Broadcasting with Prediction and Selective Forwarding in Vehicular Networks

Broadcasting in vehicular networks has attracted great interest in research community and industry. Broadcasting on disseminating information to individual vehicle beyond the transmission range is based on inter-vehicle communication systems. It is crucial to broadcast messages to other vehicles as fast as possible because the messages in vehicle communication systems are often emergency messages such as accident warning or alarm. In many current approaches, the message initiator or sender selects the node among its neighbors that is farthest away from it in the broadcasting direction and then assigns the node to rebroadcast the message once the node gets out of its range or after a particular time slot. However, this approach may select a nonoptimal candidate because it does not consider the moving status of vehicles including their moving directions and speeds. In this paper, we develop a new approach based on prediction of future velocity and selective forwarding. The current message sender selects the best candidate that will rebroadcast the message to other vehicles as fast as possible. Key to the decision making is to consider the candidates’ previous moving status and predict the future moving trends of the candidates so that the message is spread out faster. In addition, this approach generates very low overhead. Simulations demonstrate that our approach significantly decreases end-to-end delay and improves message delivery ratio. 1. Introduction Vehicular ad hoc networks (VANETs) are mobile ad hoc networks (MANETs) between road-bound vehicles such as cars and trucks. Vehicles play important roles in our daily life. Nowadays, vehicles are becoming more and more intelligent. Smart vehicles integrate environment-aware, route-planning, decision-making and drive-assistant technologies. The technologies contain computers, sensors, communication, artificial intelligence, and control technology [1]. VANET has attracted considerable attention from both research community and automotive industry. Many automobile manufacturers started planning to build communication devices into their vehicles for purposes of security, convenience, and comfort. In addition, the increasing importance of VANET has been recognized by the governmental organizations. The Federal Communications Commission (FCC) has allocated particular spectrum for intervehicle communications. Many attractive applications have emerged [2] with the development of the VANET. The first application is “Collision Avoidance.” About 40 thousand deaths occur every year in USA [3]. Many of them are