Measurements and modeling of Line-of-Sight UWB channel in underground mines

The necessity for wireless communications in underground mines is well understood. Some companies have started to deploy modern wireless system networks in mine galleries with the objective of increasing safety and productivity. In the last decade, ultra-wideband (UWB) technology has gained much interest for its applications in wireless communications. A number of UWB channel measurement have been published in the literature. However, all these works treated environments such as office buildings, residential or industrial. This paper reports on experimental results of UWB channel characterization in underground mines. The communication channel is still not well modelled in these environments. Important channel parameters such as path loss exponent, shadow fading, spatial correlation, small-scale fading, rms delay spread and mean excess delay are investigated. This work has been carried out at the underground communications research laboratory LRCS1, and at the experimental mine CANMET (Canadian Center for Minerals and Energy Technology) in Val-d'Or, Canada.