A new VLC channel model for underground mining environments

Due to the frequent dramatic disasters of underground mining collapses, the establishment of a reliable communication system in the underground mining environment is of vital importance. Instead of using the conventional wired and radio communication systems, researchers have considered the use of visible light communication (VLC) for underground mining communications (UMCs). In this paper, we extend the recursive method to model VLC propagation channel and focus on two different parts of underground mining communication, namely the working face and mining roadway. Both the required illuminance and VLC channel characteristics are thoroughly investigated for miner-to-miner (M2M) and infrastructure-to-miner (I2M) communication scenarios. It is shown that the illumination standard requirements can be fulfilled in the two parts and the mining roadway is brighter than the working face environment. Furthermore, VLC channel characteristics, such as the channel gain, mean excess delay, root mean square (RMS) delay spread, are thoroughly investigated. It is found that the proposed channel model is sufficiently accurate when taking the line-of-sight (LoS) and the first order reflections into consideration.