Discussion on mine broadcasting system and its application in coal mine emergency communicatio

Development history of mine broadcasting system and the research status of mine broadcasting system based on IP technology, mine broadcasting system based on CAN bus, and mine broadcasting system based on wireless Mesh network were introduced. The characteristics of three kinds of broadcasting systems are analyzed. Mine broadcasting system based on IP technology realizes reliable and fast emergency notification from ground dispatching room to underground working surface, but the optical cable is mainly laid in the roadway, network coverage is low, besides, the use of IP broadcasting requires a lot of IP space, and because the mine environment is complex,the equipments are difficult to set up and receive signals, and have poor resistant capability to disaster. Mine broadcasting system based on CAN bus has the advantages of long transmission distance, fast communication rate, flexible communication method, stable transmission, etc., but because each node unequally shares the bus bandwidth, there will be situations where multiple nodes compete for the bus at the same time which affects stability and real-time performance of communication. Wireless Mesh network has the advantages of high reliability, wide coverage, and flexible networking. However, due to the multi-hop mechanism of the wireless Mesh, as the scale of wireless Mesh network expands, more and more hops are connected, and the total accumulated delay is great. It is pointed out that with the transformation and upgrading of coal industry and the continuous improvement of safe production technology in coal mines, mine broadcasting system will develop in the direction of improving disaster resistance, diversified functions, system intelligence, and multi-system integration; application prospects of mine broadcasting system in coal mine emergency communications is summarized from three aspects of safety monitoring, dispatching command, information transmission, it is pointed out that the combination of mine broadcasting system and personnel positioning system is a typical model of future coal mine dispatching command, adaptive function of wired and wireless routing will greatly improve resistant capability to disaster and reliability of the emergency communication system.