Abstract—The awareness of channel conditions is critical to routing and MAC protocols. But, it is challenging to assess channel conditions due to the highly dynamic nature of wireless links. As a succession to a study of IEEE 802.11 links in an indoor environment, this paper presents observations and analysis of extensive measurements on IEEE 802.11 channels in an outdoor environment. The experiments are designed to investigate the channel dynamics through metrics such as successful frame delivery rate, loss rate, and Signal-to-Noise Ratio on IEEE 802.11 networks. The objective of this work is to reveal the interaction between these metrics and their variations in time and space. The following observations were obtained. The frame delivery rate for fixed stations fluctuates over time in most scenarios. Statistics over large time intervals get bursty and do not provide valuable information about channel conditions. Generally, Signal-to-Noise Ratio (SNR) varies widely over time even for fixed stations. However, the SNR remains stable for micro time scales. As a consequence, the frame delivery does not strongly correlate with SNR. If sent at a favorable time, a set of frames is likely to be delivered successfully continuously.
Index Terms—802.11 link, channel measurement.
Chong Tang and Shaoen Wu are with the School of Computing, University of Southern Mississippi, United States (e-mail: email@example.com).
Honggang Wang is with the University of Massachusetts Dartmou th.
Wei Wang is with the Department of Electrical Engineering and Computer Science, South Dakota State University, Brookings, SD, USA.
Cite: Chong Tang, Shaoen Wu, Honggang Wang, and Wei Wang, "Measurement Based Outdoor Link Level Investigation on IEEE 802.11 Channels," International Journal of Computer Theory and Engineering vol. 4, no. 4, pp. 546-550, 2012.