代价函数权值可变的速度自适应的异构无线网络垂直切换算法  

Cost Function Weight-Variable and Speed-Adaptive Vertical Handoff Algorithm for a Vehicle Terminal in Heterogeneous Wireless Networks

作　　者：谢显中[1] 肖博仁[1] 马彬[1] 高川[1] 

机构地区：[1]重庆邮电大学宽带接入网络研究所,重庆400065

出　　处：《电子学报》2011年第10期2417-2421,共5页Acta Electronica Sinica

基　　金：国家自然科学基金(No.60872037);教育部春晖计划(No.F2007-08);航天"十一五"预研项目(No.E2007-08);重庆市教委科学技术研究项目(No.KJ110530);重庆市自然科学基金(No.CSTC2010BB2415)

摘　　要：利用移动车载终端的测速功能,针对移动WiMAX网络支持高速移动的特点,本文提出了一种在异构无线网络中的基于车载终端的代价函数权值可变的速度自适应垂直切换算法.该算法使用速度自适应策略克服了网络发现阶段采用测量网络的接收信号强度这种固定且单一的网络发现方式带来的缺点,提高了候选网络集更新速度,改进了高速移动用户网络发现的时机;进一步,在切换判决阶段使用代价函数权值可变的垂直切换算法,综合考虑了接入网络和用户的多种属性,选取代价函数值最大的网络为切换的最佳网络.仿真结果表明,本文算法可以有效地提高网络更新速度,降低网络阻塞率,减少切换次数,保证切换的有效性和公平性.Considering velocity-measure capabilities of vehicle terminals and high-speed mobile supporting features of WiMAX network,this paper proposes a speed adaptive vertical handoff algorithm with variable weight cost function for a vehicle terminal in heterogeneous networks.The proposed algorithm uses speed adaptive strategy in the discovery phase of vertical handoff,which overcomes the drawbacks of the fixed and single network discovery methods by the received signal strength.Moreover,a cost function weight-variable algorithm is used during handoff decision,which selects the network with the maximum cost function value as the handoff network.Simulation results show that the proposed algorithm can effectively improve the update rate,lower the blocking probability,reduce the switching frequency,ensure effectiveness and fairness of vertical handoff.

关 键 词：异构网络 垂直切换 速度自适应 代价函数 权值优化 

分 类 号：TN929.5[电子电信—通信与信息系统]