蜂窝网中融合多播的接入控制机制仿真研究

Research on Multicast Service Integrated Call Admission Control Scheme in Wireless Cellular Networks

无线蜂窝网络中引入了多播业务作为对现有传输服务方式的扩展,如何优化融合业务的系统性能成为了新型无线资源管理的重点。提出了一种融合多播和单播业务的呼叫接入控制机制。该接入控制机制考虑了融合业务的特征,利用预留虚拟资源为接入呼叫分配带宽。在此基础上,优化带宽抢占和服务降级策略,从而有效的提高系统整体性能。仿真结果表明,该方案能够充分利用多播业务的特点,有效降低呼叫阻塞率并提升接入用户数量。

Multicast services have been introduced into wireless cellular networks as an extension to existing unicast only services.It is essential of radio resource management to optimal system performance in the service integrated environment.A call admission control（CAC） scheme for such systems was proposed to address issues of dynamic access for integrated services.Taking the features of integrated services into account,the proposal extended virtual bandwidth reservation model to guarantee QoS of vary service classes.On that basis,optimal bandwidth preemption and service degradation policies were proposed to further increase system performance.Simulation results show that the proposed scheme can efficiently facilitate multicast transmission to reduce call blocking probabilities and achieve better service provision capacity.