978-1-4244-5113-5/09/$25.00 c©2009 IEEE RF-GPS: RFID Assisted Localization in VANETs

Abstract—Providing vehicles ’ position is essential in VANETs. Currently, GPS positioning is widely used, but the accuracy is not adequate for emerging safety applications. In order to provide accurate positioning, this paper proposes RF-GPS, a RFID-assisted localization system that reliably supports lane-level position accuracy. It improves accuracy of the GPS system by em-ploying a DGPS-like concept. It also allows vehicles without GPS to compute their position by contacting GPS equipped neighbors. We evaluate the performance of the proposed localization system via simulation. I