Efficient Utilization of WLAN Networks in the Next-Generation Heterogeneous Environments

Wireless local area networks (WLANs) offer a promising role in the fourth-generation heterogeneous wireless networks. This requires efficient and timely switching of a mobile node´s connection (called vertical handover) from cellular network to WLAN. Existing methods to initiate vertical handover do not fully utilize the WLAN potential and result in switching to cellular networks even when a WLAN network is available. We propose a hybrid approach to determine vertical handover timing with a goal to maximize the utilization of WLAN resources, while maintaining a low probability of handover failure. Simulation results indicate the proposed technique showing better performance in terms of number of ping-pong events and handover dropping probability as compared to existing techniques which are based on mean RSS, FFT and adaptive threshold.