Location Tracking Assisted Handover Algorithms for Broadband Wireless Networks

Abstract

The design of an efficient handover technique is considered a crucial topic in the cellular-based wireless networks. Feasible handover process can minimize the performance degradation as the mobile station (MS) is moving between different base stations (BSs). Based on the IEEE 802.16e standard, it is required to provide satisfactory handover performance under a wide-range of MS's moving speeds. With the requirements of providing location-based services as stated in the standard, it becomes feasible to utilize the MS's estimated location to assist the decision of the handover process. However, in order to achieve a satisfactory performance for location estimation, excessive time is required for synchronizing with multiple non-serving BSs. In this paper, two location tracking based handover schemes are proposed for achieving reduced number of handover without additional connections between the MS and the non-serving BSs. The kinematics-assisted tracking (KAT) algorithm adopts the kinematic relationship to estimate the MS's location while the non-serving BSs are unavailable. Furthermore, the geometry-assisted tracking (GAT) scheme utilizes the geometric constraints for the prediction of the MS's position. Numerical results show that the proposed GAT algorithm can effectively reduce the handover number under different environments.