A fuzzy logic based vertical handoff decision algorithm between WWAN and WLAN

Next generation wireless communications will integrate multiple wireless access networks, including Wireless Wide Area Network (WWAN) and Wireless Local Area Network (WLAN). Vertical handoff decision plays an important role in heterogeneous networks. In this paper, we propose a fuzzy logic based vertical handoff decision algorithm (VHDA) to provide ubiquitous access at any time. Our proposed algorithm considers received signal strength (RSS), available network bandwidth (B), monetary cost (C) and user preference (P) as the vertical handoff decision criteria. The proposed VHDA uses the fuzzy logic method to evaluate the performance of the available networks. Then handoff decisions are made to select the most appropriate network for the mobile nodes (MNs). Simulation results show that fuzzy logic based VHDA is able to make accurate handoff decisions, reduce unnecessary handoffs and decrease the probability of call blocking and dropping.