Joint utility optimization based vertical handoff algorithm in heterogeneous network

The next generation wireless communication system is expected to provide users with high-speed communication services through integrating multiple wireless access technologies, including cellular system, wireless local area network, worldwide interoperability for microwave access, and ad hoc network, etc. In a heterogeneous wireless network scenario, mobile nodes with multiple interfaces will be capable of choosing different access networks for service accessing and performing vertical handoff among various networks. However, the heterogeneity and incompatibility of wireless access technologies and the varieties of user service types pose difficulties and challenges to efficient vertical handoff scheme design. In this paper, the joint access network utility is modeled based on quadratic utility function and a vertical handoff decision algorithm that achieves the maximization of joint network utility under certain constraints of network load status and user handoff number is proposed. Numerical results demonstrate the efficiency of the proposed algorithm.