| According to the bad working conditions and complicated communication environment in coal mine, the communication network underground should be more flexible and adaptive. The wireless sensor network(WSN) has lots of advantages, such as easy layout, strong flexibility, high accuracy, efficientive economy, etc. It is very suitable for the mine monitoring environment.This paper mainly carried out the following research contents:First, studying the current situation and defects of the existing mine monitoring system, we put forward a mine monitoring and emergency communication system combining Ethernet and WSN. Design the network topology of the working face and the roadway. For normal work, regard Ethernet as mine communication backbone, and WSN as auxiliary communication network, transmitting the monitoring data timely and reliably; When the cable line is break, the WSN and the cable line which is not break will constitute emergency communication network, to implement the transmission of voice data timely and reliably, which is convenient for the ground control center to take rescue measures in time.Second, comparing the existing WSN routing protocols systematically, combined with the requirements of the mine monitoring and emergency communication system, put forward the routing protocol LRWF for working face. LRWF will first divide the monitoring area into different layers, and according to the different data load of layers, formulat different size clusters to balance the network energy, and then based on the time-varying discovery delay, residual energy and communication cost to build compound index for choosing road, realizing the data transmisson between clusters.Third, combined with the different working mode in the mine monitoring and emergency communication system, we put forward the routing protocol RRPR for roadway. For normal work, the wireless sensor node will select the nearest sink to be its cluster head and transmit data to sink directly, if the sink’s location is out of the node’s communication range, it will choose the relay node depending on the node energy and location;When the cable lines break, the downward sink will inform the upward sink to adjust the WS nodes between two sinks, diving the network into different layers by hop count, and choosing the next hop node depending on the neighbor latency and energy,to implement the transmission of emergency data layer by layer.Finally using OMNET++ to simulate and analysis the protocol put forward, and comparing with LEACH-M, LBUC-M and CHM-VG, through the analysis of residual energy, time delay and packet reception rate, the designed reliable routing protocol is more suitable for mine. |
