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Frequency selection for the wireless communication in coal mine underground based on the hybrid waveguide theory

Based on the theory of hybrid waveguide, the paper analyses and simulates the loss of radio propagating in rectangular tunnel of the coalmine underground. The values of the simulation are agreed with what measured practically in other papers. At last, it deduces the most advisable frequency point for the wireless communication system in the coalmine underground so as to build the strong basement for the new generation wireless information system for the coalmine.