Mobile Direction Assisted Predictive Base Station Switching for Broadband Wireless Systems

Many broadband wireless access (BWA) systems, such as IEEE 802.16e, support high-mobility users traveling at vehicular speeds. BWA systems capable of high data rates and low bit-error rates typically require micro-cell or pico- cell deployments. High-mobility users usually need to perform frequent handovers in smaller cell structures, which could drastically increase system overhead and thus degrade the overall network performance. This paper presents a new handover decision algorithm for BWA systems, called predictive base station switching (PBSS). PBSS makes use of the mobile speed and direction information to reduce the number of handovers without degrading the received signal level. It is demonstrated via simulation results that PBSS performs better than existing algorithms based on signal levels and distance information, even when the mobile stations move randomly or when accurate direction and speed information is unavailable.