Vertical Handoff Algorithm Based on Type-2 Fuzzy Logic in Heterogeneous Networks

Currently, to ensure seamless roam across heterogeneous wireless technologies, efficient vertical handoff algorithms are required to enhance QoS and offer reliable pervasive computing environment. This study reviews traditional and classical artificial intelligent approaches adopted for vertical handoff across heterogeneous networks. A type-2 fuzzy multi-parameter based vertical handoff decision algorithm is proposed. The proposed algorithm considers five parameters of network and user, and applies a multi-mode smart terminal based speed adaptive vertical handoff policy. The speed adaptive policy overcomes the update drawbacks of the fixed, single network discovery methods by using RSS in the network discovery phase. Simulation results show that the proposed algorithm can effectively improve the network update speed, lower network blocking probability, and assure the effectiveness and fairness of handoff compared with vertical handoff algorithm based on traditional fuzzy logic.