Research On Key Technologies Of Mine Wireless Sensor Monitoring Network

China is rich in coal resources, and coal production is a pillar industry of the energy production industry. It is very important in the national economy. But due to the complex terrain of China’s coal mine, the relatively low level of automation and the poor safety monitoring system, the accidents in the mine occur occasionally, the safety situation of coal production is pessimistic. The poor monitoring technology and frequent occurrence of accidents bring about seriously affect the sustainable development of coal industry and social stability. Therefore, it is very necessary to build a stable and effective system of mine monitoring network.With the rapid development of science and technology, the Internet of Things technology has been widely applied. In the IoT industry, wireless sensor network technology acts as the key technology of the awareness, through collecting distributed processing large amounts of information to improve the precision of the monitoring and fault tolerance performance’s has become an emphasis between many research scholars and research institutions. WSN was applied to the special environment of coal mine, building intelligent monitoring network, timely and accurately transmitted sensed information to the ground stations, providing a powerful guarantee for safe production. In this paper, due to the special circumstances in mine, key technologies of WSN including packaging anti-interference technology, media access control protocol, routing protocol and positioning technology have been studied.Sensor encapsulation is the foundation of sensor technology, special material package can effectively avoid all kinds of electromagnetic interference in the mine, improving the transmission capacity of signals. This paper developed a new wireless sensor packaging materials-lithium zinc ferrite microtubule/nickel-plated carbon fiber composite materials, which can effectively absorb electromagnetic interference and improve the quality of communication.Sensor nodes transmit information to other nodes through the wireless transition method. Its communication bandwidth is very limited. Therefore we need to design a reasonable and feasible MAC layer protocol to avoid conflict so as to improving the utilization ratio of the channel and the performance of network. In this paper, combined with the special performance requirements of MAC layer protocol design and mine wireless sensor network, presents the design principles of mine wireless sensor network MAC protocol, and designs CC-MAC protocol effectively solving the conflict problem, reducing the network delay on the basis of the principle.In WSN of mine, the routing protocol plays a very important role. A good routing protocol can greatly improve the performance of the network. This paper makes improvement based on the LEACH and CTP protocol respectively, improved protocol is mainly applied in the mine environment-a wide range of networking and transmissing data in the long straight Tunnel. By improving clustering and cluster head selection mechanism of the LEACH protocol improve the stability of mine wireless sensor network and prolong the network life cycle.Due to the CTP protocol analysis of the load imbalance problem when choosing the route consider optimal path and the number of child nodes to solve the problem, this paper designs the routing metrics V-EETX and presents B-CTP routing protocol. B-CTP can achieve load balance, energy efficient and high reliability.Monitoring of coal mine environment is relatively poor, the signal interference will bring bigger error to the measured distance of the unknown node and the known node in the process of positioning. So in order to achieve high precision positioning, in the process of trilateration need to minimize the error. According to the characteristics of the mine monitoring network, this paper presents an improved trilateration localization algorithm, positioning in the process of selecting minimum three nodes from all beacon nodes meeting cond(A) as a beacon node, through the selection of beacon nodes to calculate the coordinates of the unknown node, thus reduced the effects of beacon nodes coordinate error.