Realization And Interconnection Of Wireless Sensor Monitoring Network With Mesh Structure And Multi Parameters In Coal Mine Environment

The nature and exploitation condition of the coal mine is very complicated and various, also the existing wired monitoring system can hardly monitor all regions of the coal mine which increase insecurity of coal mine exploitation. There are various disasters in coal mine, such as gas, coal dust. It is necessary to monitoring those parameters to prevent the occurence of coal mine accident. Realization and interconnection of wireless sensor monitoring network with mesh structure and multi parameters in coal mine environment is designed in the paper for implementing large scale and diversified information in coal mine. Firstly, reliable data collecting mechanism of wireless sensor network (WSN) is designed. And then interconnecting multi-WSNs is used to enlarge its coverage. After that, accessing multi-WSNs to WiMAX system realizes WiMAX user convenient visiting wireless sensor network.In the wireless sensor network aspect, wireless sensor network is deployed as mesh structure and link quality aided least hop multipath routing mechanism is designed. Wireless sensor network combine two working mode of periodic monitoring and interrupt for the purpose of long time information collecting and early warning over-limited parameter. Wireless sensor network is a self-organization and dynamic network and its network topology structure varies momentarily. Therefore a management method of network topology structure is designed for the wireless sensor monitoring network.Interconnection of wireless sensor network contains two aspects, one is interconnection between wireless sensor networks, and the other is interconnection between wireless sensor network and WiMAX system. WSN Control Unit is designed for single wireless sensor network, and then we interconnect multi WSN Control Units to form mesh network by JXTA platform enlarging the coverage of wireless sensor network. WSN-WiMAX Gateway is designed to access multi wireless sensor networks to WiMAX system. WSN-WiMAX Gateway is responsible for communication with WiMAX user and exchanging message with WSN Control Unit by JXTA platform. Realization process and message transmission mechanism of WSN Control Unit and WSN-WiMAX Gateway is designed in the paper.At last, we have a complete test for realization and interconnection of wireless sensor monitoring network. We test network deploying and data collecting in laboratory environment. We also test information monitoring and distance between sensors nodes in coal mine. Test results indicate that the performance of the network has achieved the expected target which is the network can monitor multi-parameter of coal mine periodically and can warn when the data overrun. In the interconnection aspect of wireless sensor network, the end-to-end communication from WiMAX user to wireless sensor node is tested. Moreover, we test software process delay and JXTA round-trip time (RTT). Test results show that the design is reasonable and scientific.