一种基于预测式公平队列调度算法的802.11e MAC层机制

A Predict Fair Queuing Based IEEE 802.11e MAC Layer Protocol

在共享媒体的通信系统中,队列调度的公平性是很重要的。该文在研究了IEEE WLAN已有的各种队列调度算法的基础上,提出了一种预测式公平队列调度算法(Predict Fair Queuing,PFQ),并结合IEEE 802.11e的EDCF(Enhanced Distributed Coordination Function)机制提出一种基于PFQ的新的MAC层协议——P-EDCF(PFQ-based EDCF)。该协议通过引进PFQ算法来修改EDCF的优先级控制方式,提供一种公平、高效的接入机制。仿真结果表明,该机制很好地改善了EDCF的性能,为各种类型业务提供了公平的服务。

Fairness is an important issue when accessing a shared wireless channel. This paper presents a new fair queuing method-PFQ, after studied some fairness solutions presented recently to IEEE WLAN. And then presents a new IEEE 802.11e MAC layer protocol-P-EDCF by introducing PFQ into EDCF（Enhanced Distributed Coordination Function）. This new protocol is fairer and more efficient in channel accessing by modifying the priority control method of EDCF. The results of simulations proves that P-EDCF performs much fairer than EDCF without reducing the efficiency of the system.