期刊名称：International Journal of Future Generation Communication and Networking
印刷版ISSN：2233-7857
出版年度：2016
卷号：9
期号：1
页码：79-96
DOI：10.14257/ijfgcn.2016.9.1.08
出版社：SERSC
摘要：Link adaption varies channel parameters to match dynamic changes in wireless link in order to achieve an optimal throughput performance. It is a very important research issue in Wireless LANs(WLANs), but there is few description about that in 802.11 specifications. In this paper, we propose an Enhanced Minstrel Link Adaption (EMLA) scheme, which is partly based on Minstrel and includes three parts of SNR Calibration, MCS Protection and Guard interval(Gi) Adaption. SNR Calibration is a mechanism to estimate the downlink SNR from transmitter side via probing. The more accurate of the SNR estimation brings the more rational of the MCS selection, thus the transmitting error ratio decreases.MCS Protection provides a MCS range according to the SNR estimation and only MCS in the range is permitted to select on transmitter, which prevent the MCS from misadjusting, then PHY_rate of transmitting is protected. Another improvement comes from the Gi adaption. By choosing the Gi mode dynamically, the transmitter can adapt to the channel state and extend effective transmission time. The experiment and simulation shows, in contrast to Minstrel, EMLA can cope with the worsening of the throughput caused by collision, interference and time varying effectively, therefore network performance enhanced.
