【摘要】 对掉话率的控制是蜂窝网中一个非常重要的QoS(Quality-of-Service)问题,而小区半径的不断变小以及网络中需要支持业务种类的增多使这一问题变得更为复杂。因此,在会话申请接入系统时就必须使用良好的接入控制(AdmissionControl)方法。该文提出了一种基于自适应门限调整的CAC方案(AT-CAC),该方案可以根据实际的掉话率来调整接入门限并对不同的会话采取相应的处理方法,如接纳、拒绝、排队。仿真结果显示,AT-CAC具有良好的性能和自适应调整能力。更多还原

【Abstract】 How to control hand-off dropping rate is a very important Quality-of-Service(QoS)issue in cellular networks.The current trend in cellular networks of reducing cell size and increasing services will make this issue more difficult to resolve.A novel CAC scheme based on Adaptive Threshold control(AT-CAC)is proposed in this paper.AT-CAC can adjust admitting threshold according to hand-off dropping rate and process session requests in different methods,e.g.accepting,rejecting and queuing.It can control hand-off dropping rate effectively and increase system utilization rate at the same time.Numerical results show that AT-CAC meets the design goal and outperforms the static reservation scheme under fluctuation of system load.更多还原