Study on the Effect of Frequency on Conductivity of Underground Strata in Coal Mine Through-the-earth Wireless Communication

The relationship of conductivity and the frequency, which is of decisive significance in through-theearth wireless communication in coal mine, is closely related to the options of frequency range in coal mine wireless communication. When through-the-earth wireless communication is applied, the electromagnetic waves need to spread in the semi-conductive medium rocks. The main factors affecting the electromagnetic wave propagation in rocks is the rock strata electromagnetic parameters. These parameters are magnetic permeability μ (H/m), dielectric constant ε (F/m) and electrical conductivity σ (S/m). In these parameters, electrical conductivity is not constant. Under the influence of various factors, it will be great changes. This paper, for the specific circumstances of coal mine rock, discuses and conduct dada mining the effect frequency on the electrical conductivity of underground rock in coal mine with through-the-earth wireless communication. Copyright © 2014 IFSA Publishing, S. L.