A Filtering Method for Improving the Precision of Cooperative Positioning in VANETs

Vehicular Cooperative Positioning (CP) is a recently emerged concept to estimate or improve position information of vehicles in Vehicular Ad-Hoc Networks (VANETs). Using CP, positioning accuracy and availability is improved in the areas without (or with poor) availability of the Global Navigation Satellite System (GNSS) signals. CP is based on vehicular communication for which Dedicated Short Range Communication (DSRC) is considered as a standard medium. Considering the aspects and constraints of DSRC, participating infrastructure nodes in a CP system must be installed along the streets, especially in dense urban areas. This geometrical arrangement can lead to reduced Dilution of Precision (DOP) which has an impact on the performance of a CP technique. In this article, the effect of such typical geometry on the performance of two typical CP methods, rangebased and range-rate-based, is investigated. The DOP is analysed for these CP methods and a filtering method is proposed to improve the precision of positioning.