To overcome the frequency-selective fading of ultra wide band (UWB) caused by the multi-path propagation in complicated environment of coal mines, an underground wireless communication system of UWB based on multi-band orthogonal frequency division multiplexing (MB-OFDM) for coal mine is presented. Inde-pendent angle impulse response is used to build up revised channel model for underground tunnels based on the traditional S-V model. With the revised channel model, we construct the underground UWB system based on MB-OFDM and give the band division scheme and the correction approach for channel. The model of the system was simulated in the complex environment of coal mine. Simulation results and analysis show that the underground wireless communication system of UWB based on MB-OFDM can effectively with-stand multipath fading and has the advantages of high anti-noise ability, low bit-error rate, and wide cover-age.
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