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A Coal Mine Environmental Monitor System with Localization Function Based on

ZigBee-Compliant Platform Beijing, China Abstract—This paper describes and implements a new type of coal mine safety monitoring system, it is a kind of wireless sensor network system based on ZigBee technology。 The system consists of two parts underground and surface。

Wireless sensor networks are constituted by fixed nodes, mobile nodes and a gateway in underground。 PC monitoring software is deployed in the surface。 The system can not only gather real-time environmental data for mine, but also calculate the real-time location of mobile nodes worn by miners。

Keywords： ZigBee; localization; wireless sensor networks; coal Mine

I。RESEARCH STATUS

As an important energy, coal plays a pivotal role in the economic development。 Coal mine monitoring system, is the important guarantee for

coal mine safety and high efficiency production [1]。 In order to ensure the safe operation, the installation of environment monitoring node in tunnels to real-time detection is very important。 However, commonly used traditional monitoring node wired connection to obtain communication with the control system, this node exist wiring difficulties, expensive and other shortcomings。 In contrast, wireless sensor node can be easily with current mine monitoring network connection, and good compatibility, facilitate constituted mine gas monitoring network, to suit various size of mine applications。 Since wireless nodes are battery powered, so completely out of the shackles of the cable, shorten the construction period can be arranged at any time where the need to use。

The ZigBee wireless communication technology is used in this coal mine environmental monitor system。 This is a new short-range, low complexity, low power, low data rate, low-cost two-way wireless communication technology [2]。 Now, wireless sensor network product based on ZigBee technology are quantity and variety, but the real product can be applied in underground environments of special sensor node is very few[3]。 The sensor node that we designed in the system is truly able to apply to in-well environment, it through the wireless sensor node security certification。 At the same time, due to the special nature of

the wireless network is that it can spread the wireless signal, we can easily locate staff for coal mine safety monitoring provides more protection [4]。

II。SYSTEM ARCHITECTURE

This system is a comprehensive monitoring system which is combined with software and hardware。 Hardware part includes wireless mobile nodes and fixed nodes which were deployed in the underground tunnel, the main function of them is to collect coal mine environment data and require person’s location。 Software part refers to the PC monitoring software which is designed in VC++ is used to summarize and display the data of each node。

Monitoring node is pided into mobile nodes and fixed nodes; they are using ZigBee protocol for wireless transmission of data。 Because the fixed node is also using wireless data transmission method, so it's deployed in the underground roadway becomes very convenient。 As the mobile node is carried by the miner, it must be using wireless transmission method。 This allows the mine to form a topology of ZigBee wireless sensor network。 The fixed node in wireless sensor network is router device and the mobile node carried by miner is the end device。