802.16j集中和分布控制模式传输效率分析与仿真

Analysis and Simulation of the Transmission Efficiency in Relay-based 802.16j Centralized and Distributed Scheduling

具有中继功能的802.16 j协议,是为了增加基于802.16e网络的覆盖能力和容量。新的网络结构在原有网络基础上加入了中继站来进行中继通信,既可以增加本小区网络的覆盖范围,又可以解决非视距传输问题。针对加入新的中继站,带宽资源的控制和管理不再由基站统一管理,IEEE标准制定工作组定义了两种控制方式——集中式和分布式,但没有定义两种控制模式的适用范围。通过分析和仿真说明,集中式适用于拓扑简单的网络,可以提高小区资源利用率;而分布式适用于复杂网络,从而减少信令交互次数和延时。

Being an evolution of IEEE 802.16e, IEEE 802.16j mobile multi-hop relay is proposed to gain coverage extension and throughput enhancement. Relay Station （RS） has been added in the new network to extend the coverage as well as to improve Non-Line-of-Sight. However, these new RSs involve many new problems. For example, the bandwidth resource is not allocated by Base Station （BS） only. As a result, Centralized and Distributed bandwidth request and allocation mechanisms are proposed in 802. 16j Draft Standard. However, the application area of these two mechanisms is not defined in 16j Standard. Our analysis and simulation show that Centralized Scheduling suits simple network and Distributed Scheduling suits complex network.