基于突发流的星载光交换数据信道调度算法

An On-Board Optical Switching Data Channel Scheduling Algorithm Based on Burst Stream

根据卫星光交换网络应用需求,借鉴现有的地面光交换信道调度算法,综合考虑资源预留和调度算法,提出了一种基于突发流资源预留的星载光交换信道调度算法。通过流量估计把突发数据按照目的地址和突发区服务质量(QoS)区分为单个突发和突发流,并分类进行资源预留。把数据信道按照优先级划分成不同的信道。不同优先级的突发包先搜索对应级别的信道,高优先级的或者突发流可以抢占低优先级的信道。理论分析与仿真比较证明,该算法不但降低了光交换矩阵的重置时间和交换时延,也提高了链路利用率。复杂度在最坏情况下与可插空最近可用未调度信道(LAUC-VF)方式相同,丢包率在负载为0.5时平均达到10-7,适用于星载光交换系统。

According to the requirements of satellite optical switching network, an on-board optical switching scheduling algorithm based on data burst stream resource reservation is proposed combining the ground optical scheduling algorithm considering resource reserve and scheduling algorithm. Flow-estimation prediction is used to differentiate the data burst into single burst and burst stream according to the destination address and emergency package quality of service （QoS）, and then resource reservation with different classifies is accomplished. The data channels are classified into different channels according to priorities. Different kinds of data bursts search the corresponding level channel, but high priority burst or burst stream can reave low level channels. From the comparison results of analysis and simulation, the reconfiguration time and switching time delay of optical switching matrix are not only lowed, but also the channel utility is improved. The algorithm complexity is also the same as latest available unscheduled channel with void filling in the worst condition. Packet loss rate is 10-7 on average when the load is 0.5, so the algorithm meets the requirements of optical satellite communication.