Design And Realization Of The Mine-Coal Wireless Communication

With the rapid development of coal industry, more and more high level of mechanization and information, production safety requires communication network to cover the whole area of mine coal. As abominable and complex environment, workspace, together with branch of tunnel almost becomes bind zone, by raising some special demand and challenge. Wireless communication in mine coal is a problem demanding prompt.On one hand, due to the complex terrain and enclosed underground space, wireless signal transmission interference is very serious in the branch of tunnel, which leads to a short communication distance between point-to-point nodes and much more mistakes happened. On the other hand, nodes in the net would lose efficacy or some new nodes will be added to the net. So, the structure of network will be changed. The paper, considered the trouble of mine coal wireless communication, presents an easy to implement kind of underground wireless communication scheme, which designed mine coal transmission protocol with feature of adapting to mine coal environment, simple structure, dynamic topology, reliable transmission and so on. Also, combining with the design hardware device conforms to the protocol, tests were used to measure performance of protocol’s reliability, stability and transmission rate.This paper mainly researched on the following parts:(l)Combined with model theory and geometrical optics method for wireless signal transmission characteristics of underground mine coal environment modeling and analysis, as well as simulation of attenuation model.(2)It designed the structure of mine coal transmission protocol on the basis of understanding the theory of wireless transmission in mine tunnel, also expounded systematically partition of protocol layer, services of each layer provided.(3)The design method and principle of physical link and routing layer was detailed described. Related structure of this layer, putted forward and designed a distributed wireless transmission scheme with multichannel and multi-interface, at the same time solved the resulting problem of channel allocation. Designed fast establish routing path and fast rebuild routing to adapt the easy change structure of network which was caused by the environment of underground tunnel.(4)Described detailed the design method of transmission and application layer which provided reliable data exchange. Expounded mine coal wireless transmission protocol how to realize reliable data transmission and flow control in such a terrible interference environment, also designed heartbeat scheme to improve lifecycle.(5)Designed and implemented devices hardware which corresponded requires of MWTP, including:transceiver module, each network node device, and some other assistant modules.(6) The test environment of the system and the experimental test results under different environment are given; described the analysis of experimental results, and developed data package monitor software to sniffer and verify.The paper researched and designed mine coal transmission protocol, realize reliable transmission protocol with multichannel and multi-interface. The data, including data source of workspace and monitoring data of tunnel branch, is transferred to backbone network in main tunnel by a serial of network nodes stable, which are running the reliable transmission protocol MWTP.