Map Matching Algorithm Design And Realization

With the increasing of vehicle traffic, traffic jam is becoming more and more serious and thus the requirement for real-time and accuracy of navigation system more and more high. Compared with developed countries, China is late in navigation system and the domestic technology falls behind developed counterparts. Map matching algorithm, however, can mitigate this deficiency of navigation system, by means of correcting GPS data to guarantee vehicle accurate positioning. Current map matching algorithms, still, are not perfect to realize this function, especially under some scenarios. Therefore, designers will combine several algorithms to propose a reliable map matching algorithm.In this paper, algorithm based on topology and that based on weights will be considered and combined to design a novel map matching algorithm which takes distance, direction and path similarity into account. After computing error area, this algorithm will compute and compare matching degree of each candidate path and finally show vehicle position. This system is developed on Carbide C++. The work finished is as follows.1.Analyze current map matching algorithm and make the requirement investigation of this system. The function of this system consists of four functions:error area determination; matching path selection; position correction and matching position output. Two subfunction is determined in path selection, which are matching degree computation and weight automated allocation, respectively.2.Design map matching algorithm and corresponding coding work independently.3.Join part of algorithm testing and simulate with MatLab independently. GPS data Record of Running vehicle is employed in simulation, especially for parallel paths, section turning paths and cross sections.During debugging, the system runs well and reliably with a good user experience. The test and simulation confirms that the algorithm designed in this paper can work in real-time high accuracy and reliability required cases. It can meet the demand of navigation systems.