Message-Efficient Route Planning Based on Comprehensive Real-time Traffic Map in VANETs

Abstract

Traffic congestion has become one of the major society issues in many urban areas around the world. It greatly increases the commuting time and fuel consumption. Researchers have proposed many solutions in different aspects to alleviate this issue. In recent years, many works adopt Vehicular Ad Hoc Networks (VANETs) to relieve the problem. Vehicles with communication ability can receive traffic information from infrastructures or other vehicles. Furthermore, drivers can select its driving path by avoiding congestion areas based on the real-time information. However, to speed up the procedures of information collections, many existing works suggest proactive messages to acquire traffic information from other vehicles, which incurs heavy communication overheads. In this work, we propose a real-time traffic collection mechanism, which adopt both proactive and passive schemes. Vehicles passively collect traffic information in most of the time, and proactively broadcast the traffic data only in certain situations in order to speed up urgent information spreading. Thus, vehicles can obtain real-time traffic information in a low-cost way. In addition, we propose a routing planning scheme, which considers travel time, reliability, expected traffic flow as well as other factors, to select reliable and fast routes for vehicles. The simulation results show that, comparing with previous works, the proposed schemes can find better driving paths for vehicles with lower communication cost.