Research On Three-Dimensional Localization Method Based On Mobile Anchor In Wireless Sensor Network

In recent years,the development of WSN,which is widely used in many areas such as smart home,medical care,safety production,environmental monitoring and military reconnaissance,becomes more mature.Node localization algorithm,without the support of which the perception data will loss its value,is an indispensable technology in the WSN application.In fact,the sensor nodes are basically used in 3D space,so this paper focuses on how to realize effectively the node localization in 3D space.First of all,the distribution density of anchor nodes directly determines the positioning accuracy,and to a large extent,the cost of the grid depends on the number of anchor nodes.In addition,most of the researches on node localization algorithm,which is limited to in the 2D space,have low precision and poor stability when they are applied in the actual 3D space.In this paper,we use the mobile anchor node to assist the node localization in 3D space and propose the improved algorithm.In the 3D monitoring space,when the sensor node measures the distance between the anchor nodes based on RSSI,the mobile anchor node is used to assist the node localization,and then the improved motion trajectory is proposed for the mobile anchor node,which solves the problem of how to realize the node localization when the fixed anchor node density is low.And then,when the distance measurement technology is adopted to realize the node localization in 3D space,signal strength values near the nodes,which needs to been collected,are easily affected by the environment,which will result in a certain error of ranging results.This paper will use the improved algorithm applicable for 3D space to modify the received value,and then weighted centroid algorithm and extended Calman filter are used to deal with this value,and at last get the optimal value,the higher positioning accuracy and the lower distance error.In the end,a simulation platform is built in Matlab and the simulation results show that in the 3D monitoring space,compared with the traditional algorithm,improved localization algorithm in this paper have higher effect in improving positioning accuracy,network coverage rate and execution time.