Research On Wireless Sensor Network Localization Algorithm In Underground Roadway

Wireless sensor network(WSN)has been widely used in underground tunnel to monitor its environment and track targets for its advantages,such as mobility,low cost,high reliability and easy installation.Most of the wireless sensor nodes are fixed on underground and unchanged.However,in the actually environment such as underground tunnel,the staffs and other related nodes have mobility,the simple static positioning or simple dynamic positioning is difficult to satisfy all applications,therefore,this paper proposed a fixed node localization algorithm and a mobile node localization algorithm for its different needs.First,according to the structure of the underground tunnel,an improved 3D DV-HOP fixed node localization algorithm is presented,and then presents a Monte Carlo mobile node localization algorithm.This paper’s main research contents are as follow:(1)This paper proposed a fixed node localization algorithm based on 3D DV-HOP in underground,This method analyze the model of underground tunnel and deficiency of traditional three dimension DV-HOP algorithm in detail,and make full use of the information of underground’s long space and RSSI model to modify traditional DV-HOP to improve the positioning accuracy.First it employs the relationship between RSSI and distance to modify the hop count of DV-HOP,and then the accumulative error correction is made by using differential theory.Finally,3 anchor nodes are selected to localization to improve the position accuracy.The simulation results show that the improved algorithm can greatly improve the positioning accuracy of fixed nodes,and suitable for underground positioning.(2)This paper proposed a improved Monte Carlo mobile localization algorithm on tunnel underground based on signal strength.On basis of detailed analysis of the Monte Carlo algorithm and improved underground Monte Carlo algorithm,because of those algorithms exist shortcoming,this paper combine underground tunnel structure with signal strength to modify those algorithm to improve positioning accuracy.First it utilizes signal strength to judge the move direction,and then based on the position of previous time and move speed to construct sampling area.Finally it filters samples based on one hop beacon node.The simulation results show that the improved algorithm can greatly improve the positioning accuracy of mobile nodes,and suitable for underground positioning.In summary,this paper focus on underground tunnel,and propose fixed node and mobile node localization algorithms based on its spatial structure,and verified those algorithms bymatlab simulation experiment.The experimental results show that,the two proposed algorithms have improve positioning accuracy,and it is more accurate to achieve the purpose of environmental monitoring and target tracking on underground tunnel.