Abstract: The handoff mechanism is a key technology which can provide user with seamless mobile application services in wireless communication system．It also has very important impact on user oriented service experience and application．In this paper,a context-aware and mobile location prediction based handoff mechanism was proposed,which uses the modified Dempster-Shafer theory together with a variety of context information to predict the location of mobile users．The proposed method can not only efficiently avoid "ping-pong" handoff,but also shorten handoff delay,and provide basis for fast,accurate and reliable decisions,and reserve resources in advance．Thus,it can significantly improve the QoS(Quality of Service)of network．Theoretical analysis and simulation results show that location prediction is closer to user’s real trajectory.The RMSE of position is smaller,which means the success rate of handoff is largely improved.

Key words: Handoff mechanism,Context,Dempster-Shafer(D-S)theory,GIS(Geographic information system),Hausdorff distance