Design And Implementation Of Rescue Integration Platform And Personnel Positioning Subsystem Based On Mesh Newtwork In Coal Mine

China is a country which relies on coal resource. The coal will be the China’s major consume resource for a long time. However, coal mine accidents often happen due to the harsh underground environment and low-developed mining technique. After mine accidents occurred, how to establish an emergency communication system quickly and efficiently is a severe problem placed in front of us.Aiming at the physical environment of underground emergency rescue, an emergency rescue communication network is proposed. This network is based on wireless mesh network. The logical structure and system structure of this coal mine rescue communication system is put forward. Through describing the structure and characteristics of mesh network and analyzing the actual signal underground environment, linear link wireless mesh network is selected as the backbone network of rescue communication system. At last, mesh network node is designed.According to the actual business needs of the mine rescue, an integration software platform is designed. This platform has video monitoring, voice control, personnel positioning, multi-parameter gas sensing function. Java language is utilized to design and develop interactive server, mobile client application and PC software on Eclipse platform. The design and implementation of interactive server includes user manage, XMPP connection manage, information transport and high concurrency modules. The design and implementation of mobile client application includes user login, timer and network monitor modules. The design and implementation of PC software includes software interface and enter subsystem function. At last, administer can use PC software to access all the information of a single client on the same interface.In the integration platform, the design and implementation of personnel positioning subsystem software is completed. Personnel positioning subsystem uses RSSI to implement coarse positioning, and utilizes video monitoring subsystem to implement precise positioning. The electronic map and offline map package is made by ArcGIS. And SDK provided by AccGIS is used to realize map display and personnel positioning function. Mesh network is built at the school office building corridor to simulate tunnel environment. The aim of this test is to test positioning subsystem functions. The test verifies that the designed personnel positioning subsystem will work with other subsystems, the disaster relief personnel obtains current position information by different ways according to actual situations.An eleven hops mesh network is deployed in YuShuwan coal mine. Bandwidth and signal intensity of this network is tested. At the same time, this network is used to test audio and video business. Using the designed PC software to watch the return video, the results show that the wireless mesh network can be the backbone network, and mesh network has multiple channel video and audio access and real-time feedback ability. Besides, under the condition of ensuring the transport quality of service, the single hop distance of Mesh network is tested. Finally, maximum distance between client and the node is tested. From the testing results, we can see that the max distance of Mesh node deployment is about 1400 meters.