异构网络中多媒体业务的联合呼叫接纳控制

Joint call admission control algorithm for multimedia services in heterogeneous wireless networks

提出了3G与WLAN互连的异构网络中一种多媒体业务的联合呼叫接纳控制算法,针对不同类型用户的业务特性选择合适的优先接入网络,考虑到切换用户及不同业务类型用户的优先级,分别在3G和WLAN中设置了多级的接入门限值.运用多维Markov链模型对该算法的新呼叫阻塞率和切换呼叫掉线率性能进行了理论分析.仿真结果表明,本算法在满足不同类型用户的QoS需求的同时,在新呼叫阻塞率和切换呼叫掉线率之间获得了良好的折中,提高了系统整体性能.

A joint call admission control algorithm for multimedia services is proposed in heterogeneous wireless networks of 3G and WLAN interconnection.The priority access network is selected according to the traffic characteristics of users.Taking into account the priorities of handoff users and users with different traffic classes,multi-level access thresholds are set in 3G and WLAN respectively.A multi-dimensional Markov chain model is used to analyze the new call blocking probability and handoff call dropping probability of the proposed algorithm.Simulation results show that the proposed algorithm not only satisfies the QoS requirements of users with different services,but also achieves a better tradeoff between new call blocking probability and handoff call dropping probability and improves the overall performance of the system.