Validation of the Vale Path Loss Model for Open-pit Mines in Different Stages of Mine Exploration

As in other vertical markets, wireless communications are expected to play a fundamental role in the digitalization of the mining industry. Akin to most industrial applications, careful and scenario specific understanding of the radio propagation conditions is key to plan and deploy a reliable wireless network. However, surface mining presents an additional challenge when compared to other industrial scenarios: inherent large-scale topographic variability. Therefore, it is necessary to validate if the radio propagation models remain accurate over large topographic change. In this work, we summarize and compare the results collected in two distinct measurement campaigns, with the predictions of a dedicated path loss model (Vale Model) previously derived from measurements in surface mines. The second measurement campaign is performed by means of an automated site survey, that takes advantage of operational wireless systems and mining equipment to collect data samples. The results show that even with different transmit frequencies, topographic variation, test equipment, and measurement methods (dedicated versus automated site surveys), the Vale model provides a good fit for path loss prediction in open-pit mines, with RMSE values in the order of 7 dB. Besides, this is the first time a radio propagation model has been validated over large topographic changes in a surface mining scenario.