Study On MIMO System Capacity In Coal Mine

The application of wireless communication system in coal mine undergroundflourishes with the growing demand for safety in production and rescue after disaster.The multipath effect caused by the complex communication environment is a majorproblem for mine wireless communication applications. Compared with othertechnologies, the MIMO technology has more advantages, such as anti-interference,anti-multipath, reduce the error rate, increase the channel capacity, etc. This thesistakes the MIMO system model as the research object, playing a certain role forpromoting the application of MIMO technology in coal mine.First, the existing mine wireless communication system and mine wirelesscommunication environment are analyzed. Then this thesis points out that the biggestproblem of mine wireless communication is multipath fading, and analyzes theadvantages of MIMO technology in coal mine.Secondly, on the basic of studying on the basic framework and mathematicalmode of ground MIMO technology, the thesis puts forth its capacity formula. Itproves that that the adaptive power allocation scheme is better than the equal powerallocation scheme in improving the channel capacityby simulation research.To promote the practical use of MIMO model in coal mine, the thesis sets up theMIMO channel transmission model in coal mine on the basic of assuming thegeometric distribution of scatterers and considering three scattering, and studies therelationship of the correlation coefficient with different antennas interval and differentK value. Then it analyzes the MIMO antenna configuration in coal mine by studyingthe trend of channel capacity with different antennas number and different correlationcoefficient through simulation and experiment.Finally, this thesis projects a technique to improve stadia’s channel capacity. Itimproves the channel orthogonality by changing the carrier frequency of the adjacentantenna to achieve capacity gain, and deduces the correspondent formulas of theorthogonal matrix. The simulations reveal that using the different carrier frequencycan effectively improve the channel capacity.