Abstract:

An efficient real-time traffic scheduling algorithm for WLAN(Wireless Local Area Networks) was proposed based on the classic WRR (Weighted Round Robin) discipline. The algorithm was operated at link layer level, and was coupled closely with DCF(Distributed Coordinate Function). Through that, the HOL(Head Of Line) blocking problem was alleviated. With compensation for mobile users experiencing burst channel error, the long-term fairness approximately was achieved. Extensive simulations were performed using NS(Network Simulator). The results show that the algorithm is simple,and improves the channel utilization and data throughput effectively. The average packet delay is also decreased.

Key words:  scheduling algorithm, real-time traffic, WLAN, WRR-CSDPS

摘要：

在WRR(WeightedRoundRobin,带权重的循环)算法的基础上,提出了一种适应无线局 域网特点的实时业务的调度算法。该算法工作在数据链路层,和无线局域网的介质访问控制(MAC) 层协议DCF(DistributedCoordinateFunction)紧密结合,有效避免了对列头部阻塞问题,提高了信道利 用率。通过采用补偿机制,近似达到了长期公平性。使用NS(NetworkSimulator)仿真进行性能评价, 结果表明该算法能有效提高实时业务的端端吞吐率,降低端端延迟和丢包率,延迟抖动也较小,可以 在一定程度上保证实时业务的服务质量。

关键词: 调度算法, 实时业务, 无线局域网, WRR-CSDPS