An Enhanced Vector-Based Update Algorithm for Network-Constrained Moving Clients

Location based services (LBS) is one of the fastest growing areas in recent years. Location update of mobile clients is fundamental in all types of LBS. But algorithms proposed in this field generally didn´t concern the restricted context of road network and caused some unnecessary update. This paper proposed a revised vector-based update algorithm which taking characteristics of road network into account. The improved approach adopts two-step correction to revise the predicted position of the moving clients. First, the erect correction is implemented. Second, horizontal correction is carried out based on the erect correction. The proposed algorithm is evaluated via the simulator and compared with the vector-based algorithm. Experimental results show our algorithm can significantly decrease the number of updates compared to barely vector-based strategy while having lower error, and is scalable and stable.