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A Wireless Sensor Network Used in Coal Mines

A wireless sensor network used at coal faces to acquire sensor data is designed. Based on the characteristics of coal faces, a special topology of the wireless sensor network is adopted, which makes the network more suitable for the surroundings of coal faces. By analyzing the relation between signal strength and the successful probability of communication, the route signal strength is defined and the selecting route conditions are proposed. Then, the method using the selecting route conditions to form an ad hoc wireless sensor network is put forward. Experimental results verify the validity of the algorithm. Finally, the hardware realization of the network is introduced, which supports the ZigBee standard.