Research On Routing Protocol Of Wireless Mesh Network And Emergency Communication System In Underground Coal Mine

Working conditions in underground coal mine are dreadful, resulting in frequent accidents, which have been hindering the rapid development of China's coal industry. Therefore, to reduce casualties and economic loss caused by coal mine accident, it is an urgent need to develop an emergency communication system used in coal mine.However, communication conditions are dreadful. The network is vulnerable to be damaged, so it is needed to set up a network which is simple, highly mobile and self-healing after destruction. A digital mine integrated wireless communication system based on wireless mesh network is designed. The system makes use of the characteristics of wireless mesh network, such as simple to set up, easy to move and strong self-healing. It integrates video surveillance, voice communication, personal location and emergency communication。This paper mainly completes the development of emergency communication subsystem and research on the routing protocol of wireless mesh network.Firstly, research status of communication and emergency communication in underground coal mine are analyzed, as well as the features of the new generation of coal mine emergency communication, which provide theoretical foundation for the design and development of digital mine integrated wireless communication system and emergency communication subsystem.Secondly, the network topology and logic function modules of the system is presented, and the function and implementation of each module is analyzed in detail.Thirdly, the routing protocols of the wireless mesh network are researched, and four of them are simulated on the performance. On the basis of study, improvement directions of routing protocol adapted to system are presented.Forthly, the data server of emergency communication subsystem is designed and developed. The data server implements the intelligent analysis and forwarding of message from control terminal and wireless data terminal, and it achieves unicast, multicast and broadcast of message based on the message type and destination. In addition, a mimetic data terminal is developed to simulate the function of wireless data terminal for the need of test.Finally, an emergency system based on wireless mesh network is set up using Strix's device, data server and wireless data server presented in the front of the paper. The performance of the network is tested in detail. Then the function and performance of the system is tested, and the communication process when the wireless data terminal achieves access network, data transmission and switching is tested through capturing packet, which verifies the correctness of system design.