An Optimization Method For Three-dimensional Location Accuracy Of Wireless Sensor Network

Among Wireless Sensor Network(WSN)related technologies,positioning technology is the most critical supporting technology among them.Each application of WSN matches the location information with the information sensed by the sensor.Therefore,positioning technology is one of the most critical research technologies of WSNs,but the positioning algorithms currently proposed have low positioning accuracy in complex environments.It is of great significance to ensure the positioning performance and optimize the positioning algorithm according to the changes of the environment.This paper studies and analyzes a lot of related theories and methods about positioning technology.By introducing knowledge such as correction methods,intelligent optimization algorithms,and region division method of Voronoi diagram,a new positioning method is proposed to reduce the impact of the environment on positioning accuracy and achieve the effect of improving positioning accuracy.The main work is as follows:(1)Aiming at the problem of complex mountain environment and low node density,a method based on the fusion of the three-dimensional Approximate Point in Triangle(APIT)algorithm and the Distance vector-Hop(DV-Hop)algorithm is proposed.Solve the problem of accurate location of unknown nodes in the case of sparse node deployment.When the number of anchor nodes is less than four and no tetrahedron can be constructed,the DV-Hop algorithm is introduced to locate unknown nodes.After determining the location coordinates of unknown nodes,the near-point vertical foot mean method is proposed to correct the location coordinates of unknown nodes in order to further improve the positioning accuracy.Finally,simulation experiments show that the proposed positioning method improves the node positioning accuracy.(2)In the mountain environment,it is necessary to consider both positioning accuracy and energy consumption.First a single anchor node mapping method is proposed.This method deploys a single anchor node on the mountaintop,and use a single anchor node to map multiple virtual anchor nodes to the mountain to reduce energy consumption.Then,use the weighted centroid algorithm to determine the location of the unknown node.Since the estimated value is greatly different from the actual position coordinate value,a butterfly optimization algorithm(BOA)is introduced to optimize the position of the unknown node to improve the positioning accuracy.Finally,by comparing with other algorithms in outdoor experimental scenarios,the experimental results show that the energy consumption and positioning accuracy of this positioning method are better than the other two algorithms.(3)Aiming at the problem of low positioning accuracy in a specific positioning area,an improved algorithm based on computational geometry is proposed.First,the Voronoi diagram is used to divide the positioning area to determine the area where the unknown node is located.Then,the Support Vector Machine(SVM)algorithm is used to determine the position of the unknown node in the area to improve the positioning accuracy of the nodes.Finally,verification in both indoor and outdoor environments shows that the positioning accuracy of the VD-SVM positioning method is better than other positioning methods.