Two-way TOA with limited dead reckoning for GPS-free vehicle localization using single RSU

Road safety applications in Vehicular Ad Hoc Networks (VANETs) necessitate highly accurate vehicle localization techniques. Unfortunately, Global Positioning System (GPS)-based localization techniques do not only suffer from the lack of ubiquitous GPS coverage but also are susceptible to high localization errors (10 m to 30 m). Consequently, such techniques are not suitable for road safety applications. Recently, GPS-free localization based on vehicle communication with installed roadside units (RSUs) has emerged as a more accurate alternative. However, existing GPS-free techniques require the vehicle to communicate with two RSUs in order to achieve high localization accuracy. Such techniques either increase the system cost due to the high number of needed RSUs or delay the localization decisions. In this paper, we propose a GPS-free localization framework that uses two-way time of arrival with partial use of dead reckoning to locate the vehicles based on communication with a single RSU. Our results show that the accuracy of the proposed framework is 13.1% to 20.1% better than the techniques that use 1 RSUs while completely depending on dead reckoning, and only 3% to 8.9% worse than those techniques that use 2 RSUs on both sides on the road.