Applied Research, Wireless Sensor Networks In The Coal Mine Safety Monitoring

67% of Chinese energy sources supply comes from coal mine, the abundant coal mine supply played a key role in the fighting snow disaster in 2008. In recent years, the accidents as a result of coal mine exploitation have caused a lot of damages to properties of the country and lives of our people. The research of security monitoring system on how to prevent mining disasters is a matter of great urgency. This subject is designate to improve the undeveloped mine monitoring system techniques, solve some of the hardships and problems encountered. It will provide delicate scientific data and improving the scientific monitoring level by means of wireless sensor networks.On the base of analysis and comparison, JN5121 is selected as hardware platform to accomplish the design of the portable multi-functional sensor node and the base station sensor node, including power supply management, data collection, wireless communication, LED display modules. The location of the miners is a significant part of this design, this paper brings forward a simple, project-applicable Quadrilateral Weight Centroid Algorithm on the base of Trilateration Location. The simulation results demonstrate that algorithm is more accurate. Further test has been done in work environment to the algorithm, the results proves the validity of simulation. Data collection software design and low power consumption analysis have been done to the system, the energy can be saved greatly if the end device work in sleep model in its idle status, and a pair of common batteries can supply the energy for end device working for a month. Data transmission test and underground communication distance test have also been done to the system, the results tell that this system can do long distance communication and collect the parameter of the mine environment which meets the all-round requirements of mine security monitoring.This design adopt wireless sensor network technique in mine safety monitoring system, has achieved data collection and transmission of the density of the gas, humidity, temperature and the miner's location, which achieved the goals of mine safety monitoring ,solved the restricted communication distance and inaccurate miner location technique problems. The application of this design is of great innovation and practicability which will produce great social benefits and financial benefits .This design will also contribute to the research and application of the wireless sensor network and the new mine safety monitoring system project.