Research On Underground Personnel Positioning Method Based On Wireless Communication Technology

Coal resource is an essential part of production and life in our country.The mining of coal resource is carried out all the time,but in the process of coal mining,production accidents occur from time to time.In order to rescue the trapped personnel as soon as possible after the accident and minimize the economic loss,it is necessary to monitor the position of the underground personnel.Wireless sensor network(WSN)technology has the advantages of low cost,low power consumption,high reliability,simple node and easy installation,which is widely used in underground personnel positioning system.The positioning algorithm is the key technology of underground personnel positioning system,so the research of underground personnel positioning algorithm based on wireless communication technology has practical significance.Among the commonly used localization algorithms based on WSN,DV hop localization algorithm has the advantages of simplicity,scalability and strong applicability.But in the underground personnel positioning system,because the beacon node uses the full broadcast mode for information transmission and the distance estimation error between nodes is large,the DV hop positioning algorithm has the problems of high network energy consumption and low positioning accuracy for unknown nodes.Therefore,in this paper,Fisher information matrix(FIM)is used to dynamically control the forwarding process according to the importance of beacon node information to unknown node location,so as to reduce the forwarding times and achieve the purpose of reducing the overall network energy consumption.Because the low accuracy of localization algorithm mainly comes from the low accuracy of node distance estimation,this paper adjusts the node distance estimation algorithm according to whether the nodes are adjacent or not.It mainly includes: for non adjacent nodes,the Euclidean propagation method(EPM)is used to estimate the distance between nodes;for adjacent nodes,the adjacent information is fused with received signal strength(RSS)to estimate the distance between adjacent nodes.In order to further improve the positioning accuracy of nodes,weighted least square(WLS)is used to determine the location of unknown nodes.The network simulation platform(matlab)is used to verify whether the performance of the optimization algorithm in this paper reaches the expected.The simulation results show that: compared with the classical DV hop algorithm and three improved DV hop algorithms,the optimized DV hop algorithm reduces the energy consumption of positioning by 24.87% on average,and improves the positioning accuracy by 11.86%.Therefore,the optimized DV hop algorithm meets the design requirements.