关键词: 异构无线网络, 切换决策, 服务质量, 多目标遗传优化, 总最佳连接（ABC）, 博弈分析

Abstract: In heterogeneous wireless networks, handoff decision schemes need to consider plenty of factors, such as quality of service (QoS) requirements, service costs, user preferences, mobile terminal conditions and access network conditions, and make users and network providers reach win-win situations. This paper characterizes the factors which influence handoff decisions with the knowledge of fuzzy mathematics and microeconomics. On this basis, this paper proposes an always best connected (ABC) supported handoff decision scheme with multi-objective genetic optimization, which improves the decisions quality with the help of elitist selection and individual migration. Based on game analysis, this paper finds an optimal handoff solution of assigning multiple terminals to multiple access networks to make user utilities and network provider utilities achieve or approach Pareto optimum under Nash equilibrium. Simulation results show that this scheme is feasible and effective and has better performance than certain existing schemes.

Key words: heterogeneous wireless networks, handoff decision, quality of service (QoS), multi-objective genetic optimization, always best connected (ABC), game analysis