摘要
在CDMA2000蜂窝网络和WLAN组成的异构无线网络中,呼叫接纳控制算法对于提高系统资源的利用率有着非常重要的作用。根据WLAN的网络负载情况和移动用户的速度来判决是否接入WLAN;提出一种基于概率机制的CAC算法,WLAN能够限制来自于蜂窝网的VHO呼叫,减少不必要的VHO处理负荷;对新呼叫阻塞率和DVHO呼叫阻塞率进行理论分析和推导。仿真结果表明,该CAC算法能够减少不必要的重复上下垂直切换,同时将DVHO呼叫阻塞率控制在可接受的范围内。算法保证了较高的系统吞吐量,提高了系统整体性能。
CAC between heterogeneous wireless networks,such as an integrated CDMA2000 cellular network and a WLAN,play an important role to utilize the system resources in a more efficient way.This paper proposed that the preference to the WLAN was determined based on the traffic load in the WLAN and the velocity of the cellular mobile users.Therefore,it proposed a probabilistic CAC algorithm that allowed the WLAN to limit VHOs from the cellular network to reduce unnecessary VHO processing.It derived the expressions of new call blocking rate and DVHO blocking rate.Simulation results demonstrate that our CAC scheme reduces the unnecessary VHO processing while keeping the DVHO blocking rate within acceptable limits,maintaining reasonable through put and improves the overall performance of the system.
出处
《计算机应用研究》
CSCD
北大核心
2012年第6期2321-2324,2328,共5页
Application Research of Computers
基金
国家科技重大专项基金资助项目(2011ZX03005-004-03)
江苏"973"项目(BK2011027)
江苏省2011年普通高校研究生科研创新计划项目(CXLX11_0401)
南京邮电大学青蓝计划项目(NY210033)
关键词
异构无线网络
呼叫接纳控制
向下垂直切换
向上垂直切换
heterogeneous wireless networks
call admission control（CAC）
downward vertical handover（DVHO）
upward vertical handover（UVHO）
