And Its Use Of Wireless Sensor Networks Located In The Coal Mine

The WSN is a specialized intelligent network, which includes numerous sensors of specific functions. These sensors can transmit messages to each other and perform a specific function coordinately through the self-organized wireless communication. WSN is applied to every aspect of real life, such as industrial control, health care and the underground personnel positioning system, because of various advantages like intelligence, adaptability and real-time, has applied to all aspects of life. The information gathered by sensors would be meaningful only combined with the presence of position information. Besides, position information helps to improve routing efficiency, coverage performance, etc. The study of location technology is especially crucial as it is one of the key technologies of WSN. This dissertation mainly studies the DV-Hop localization algorithm based on range-free algorithm and the RSSI localization algorithm based on range algorithm.Firstly, this dissertation introduces a detailed exposition about WSN and its classic localization technology, and then analyzes and improves the DV-Hop localization algorithm. Not only the average of every jump distance is improved, the trilateral localization method is also improved through introducing the trust of the Minimum Angle. The trust of the Minimum Angle is given different weights in the different shape of the triangle and the different angle of the Minimum Angle. At last, these weights join the final location of the node, which improves the localization accuracy.This dissertation also analyses and studies the RSSI localization algorithm. In view of the special underground environment of the coal mine, it analyzes the significance of the network node deployment, and presents the modeling method that extends the sensor to the top of the arch tunnel. After the modeling, considering the inclined triangular deployment, the two-node localization method is put forward. At last, the algorithm can produce better localization results in theory through the experimental simulation.