802.11n/ac/ad中的两级聚合重传算法设计  

Two-level frame aggregation retransmission scheme design in 802.11n/ac/ad

作　　者：钱煦 吴斌[1,2] 叶甜春 QIAN Xu;WU Bin;YE Tianchun(Institute of Microelectronics of the Chinese Academy of Sciences,Beijing 100029,China;University of the Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院微电子研究所,北京100029 [2]中国科学院大学,北京100049

出　　处：《西安电子科技大学学报》2018年第2期90-96,共7页Journal of Xidian University

基　　金：超高速无线局域网的国际标准化与技术验证研究资助项目(2012ZX03004004)

摘　　要：IEEE802.11n/ac/ad协议提出了多种聚合算法,通过多包数据帧的聚合来减少媒介访问控制子层及物理层的固定开销,提升信道利用率.然而在信道质量较差时,重传的聚合包数将剧烈浮动,导致系统吞吐率下降.文中针对误码率较高的无线场景提出了一种高效率的两级聚合重传算法.与传统聚合算法相比,首先通过媒介访问控制子层聚合滑动窗口的引入,增加了重传时聚合包的长度;其次通过对吞吐率的理论分析,根据信道误码率、当前算法聚合最大包数和当前子帧长度,动态计算得出重传效率最高时使用的第1级聚合长度和第2级聚合包数.网络仿真器的仿真验证,表明该算法在不同的子帧长度以及聚合包数条件下均能提升系统吞吐率,并且能够提升在信道误码率较高时的吞吐率稳定性.The IEEE802.11n/ac/ad support multiple aggregation schemes,which can improve the efficiency of the MAC layer by aggregating MAC protocol data units and thus reducing the overhead of the MAC and PH Y layer.However,in error-prone environments,the aggregation level of retransmitted aggregation frames severely fluctuates,incurring the instability of system throughput.In this paper,we propose a novel two-level retransmission aggregation scheme in erroneous environments.This scheme first introduces the aggregation sliding window in the MAC layer to increase the aggregation level;second,through theoretical analysis,the second level aggregation level and the first level A-MSDU frame length arc optimized and adjusted dynamically according to the subframe size,the maximum aggregation level(MAL)allowed by the current two-level frame aggregation and the real-time channel bit-error-rate(BER).Simulation by using NS-3 shows that this scheme outperforms other schemes for different subframe sizes and aggregation levels.

关 键 词：802.11n/ac/ad 两级聚合 误码率 网络仿真器 子帧长度 聚合包长 

分 类 号：TN925.93[电子电信—通信与信息系统]