A layered two-step Hidden Markov Model positioning method for mine environments based on Wi-Fi signals

The safety of miners is of interest to all countries. In the event of a coal mine disaster, how to locate the miners remains the biggest and most urgent issue. The aim of this study is to propose a precise positioning method for underground mine environments. In this paper, a layered two-step Hidden Markov Model is proposed to simulate human walking in underground mine environments and an improved Viterbi algorithm suitable for the model has been implemented. The accuracy of the positioning method is quite satisfying compared to other positioning methods in the same category. Possible improvements to the proposed method have been illustrated in the future work which makes it more suitable for different situations rather than limited by assumptions. The proposed positioning method can be claimed to be quite suitable for underground mine environments to a low cost and with acceptable accuracy.