An improved map-matching algorithm used in vehicle navigation system

Vehicle navigation system estimates vehicle location from Global Positioning System (GPS) or dead-reckoning (DR) system. However, because of unknown GPS noise, the estimated location has undesirable errors. The purpose of map matching (MM) algorithm is to locate the inaccuracy position of the vehicle to the map data that is referenced by the system. In this paper, a simple map-matching algorithm is discussed first. Then Kalman filtering and Dempster-Shafer (D-S) theory of evidence are introduced into the improved map-matching algorithm. The real road experiments demonstrate the effectiveness and applicability of the improved algorithm, and it is found to produce better results.