RSS method and fuzzy logic combined vertical handoff decision algorithm

The next generation wireless networks are envisioned as convergence of different radio access technologies, in which vertical handoff occurs when a mobile terminal switches from one network to another. To provide seamless vertical handoff and improve quality of service (QoS), the vertical handoff algorithm cannot be achieved with the use of traditional receive signal strength (RSS) as the vertical handoff criteria. At the same time, using the fuzzy logic alone can not eliminate ping-pong effect. In this paper, we propose an improved vertical handoff algorithm which uses RSS measurement as the first stage: determine the available networks first and execute pre-handoff decision, and then select the optimal network through a fuzzy logic decision algorithm. We give a vertical handoff (VHO) scenario to illustrate the performance of the proposed algorithm.