无线局域网中PCF机制的实时性能研究与改进

Research and Improvement of PCF Real-time Performance in WLAN

针对MAC层公平性问题,本文对原有DCF机制进行了改进,根据节点所处的信道状态和其转发数据比例,动态调整竞争窗口大小,进行自适应二进制指数退避。就点协调功能(PCF)状态下点协调器(PC)对各个联入PC的站点分配媒体访问权的轮询机制进行分析并加以改进,提出一种令牌缓冲器的方法,仿真结果表明,改进PCF和DCF机制与IEEE802.11协议采用的退避算法相比,在信道公平性方面有较好的改善,并且具有较高的实时性。

An active neighbor number and current bandwidth ratio based method is proposed to adjust the contention window for binary exponential backoff process to overcome the problem of fairness.A token buffer based method is proposed.The simulation results implement the improvement of original polling mechanism.