Predictive handover mechanism based on required time estimation in heterogeneous wireless networks

In most conventional layer 2 triggering approaches, a pre-defined threshold for a specific perspective such as the received signal strength is used so that it may cause too late or too early handover executions. In this paper we propose a new predictive handover framework that uses the neighbor network information to generate timely the link triggers so that the required handover procedures can appropriately finish before the current link goes down. First we estimate a required handover time for the given neighbor network conditions, then using a predictive link triggering mechanism the handover start time is dynamically determined to minimize handover costs. The handover costs are analyzed in terms of the total required handover time and the service disruption time. The numerical analysis and simulation results show that the proposed method significantly enhances the handover performance.