Modeling and measurements for wireless communication networks in underground mine environments

Abstract

One of the crucial problems being faced by wireless system designers is experimental understandings of the electromagnetic (EM) wave propagation in high stress environments, such as underground mines and tunnels, so that reliable performance can be achieved. This is driven by the fact of limited availability of real-time data of operational underground mines with different measurement considerations. This paper reports extensive experimental studies and proposes a modified multimode based channel model for wireless communication networks in underground mine environments. The experimental campaigns were carried out in an underground coal mine considering significant use cases viz. line of sight (LOS), no line of sight (NLOS), across the curves and bends, in noisy environments, straight tunnels, and near the face (extraction area). We then validated the proposed channel model with the experimental measurements. The validation results showed reliably a good agreement with a model accuracy of 94.60%, 91%, 90.98% for the straight tunnel, along the belt conveyor and near face respectively. The proposed model outperforms the state-of-the-art channel model for mine workings with model accuracy differences of 60.1%, 60.45% and 58.56% for straight tunnel, along the belt conveyor and near face respectively. A model accuracy of 78.31% is achieved across the curvature measurement scenario. Hence, the proposed channel model can be accepted for wireless communication system design and deployment planning in underground mines to provide a reliable two-way wireless communication and coverage. Furthermore, detailed link analysis of wireless sensor networks in mine workings is also discussed considering packet reception rate with respect to distance and received signal strength.