WiMAX上行链路实时业务改进调度算法

摘要

针对WiMAX建议的rtPS和ertPS调度机制处理变速率实时业务时MAC层开销大，导致时延增大的缺点，提出了一种能够有效调度多用户变速率实时业务的上行链路调度算法。该算法在SS端实时监控数据率，减少发送带宽请求的次数，从而提高整体的上行链路资源利用率，并在BS上行调度器中优化调度策略，使得最急迫的用户优先得到服务。仿真结果表明该算法与ertPS相比，在不影响系统吞吐量的情况下上行时延减少了约15%。%WiMAX standard proposes rtPS and ertPS to support real-time UL service flows. However, rtPS and ertPS bring additional delay because of huge MAC overhead while serving real-time traffic with variable data rate. An efficient multiuser UL scheduling algorithm is proposed to decrease UL delay in this paper. This algorithm improves UL resource utilization by monitoring traffic at SS, thereby reducing sending times of bandwidth request. Moreover, the most emergen-ciest uplink connection can be served in time by optimizing UL scheduler of BS. The simulation results show that the pro-posed algorithm obviously decreases UL delay by 15%and does not affect system throughput simultaneously.