Research On Optimization Of Node Localization Algorithm For Three-dimensional WSNs Based On DV-Hop

Node location technology is a key supporting technology in Wireless Sensor Networks.The acquisition of node location information in WSNs is the basis for the practical significance of the collected data.The node location algorithm in the threedimensional space can more effectively solve the positioning needs of the real world.How to improve and optimize the existing three-dimensional space node location algorithm,effectively reduce the node positioning error,and improve the reliability of the node positioning is the research trend of the node location algorithm in the threedimensional space.This paper focuses on the three-dimensional DV-Hop algorithm and proposes improved methods for its existing problems.The main work is:(1 Aiming at the problem of low positioning accuracy caused by unreasonable division of single-hop value and large average hop distance error of 3D DV-Hop algorithm,a 3D DV-Hop localization algorithm based on multi-communication radii and hop distance optimization is proposed.First,the number of one-hop is redivided using multiple communication radii.The number of multiple communication radii is calculated by referring to the number of anchor nodes existing in the network and the number of nodes existing around each anchor node so that the number of multiple communication radii is more in line with the local and overall characteristics of the network.Second,the anchor node selection method is used to screen non-coplanar anchor nodes in the set of anchor nodes received by unknown nodes,to improve the reliability of node location.The average hop distance is calculated using the anchor node pair with the largest distance and the largest similarity obtained from the search,and the distance from the unknown node to the specific non-coplanar anchor node is calculated using the average hop distance.Finally,the optimized jump value and distance value are used to calculate the position through the Min-Max method.Simulation results show that the algorithm has a good positioning effect under different communication radius,the number of anchor nodes,and the total number of nodes,which can effectively reduce the error caused by the number of hops and the average hop distance,and improving the positioning accuracy.(2 To solve the problems of the 3D DV-Hop algorithm,such as large location error of unknown nodes at the edge and inaccurate calculation of node coordinates,a 3D DVHop algorithm based on lion swarm algorithm and region localization is proposed.First,by setting the threshold of hop count and node trust value to limit the node's communication range and anchor node selection order.Second,the distance between the one-hop node and its neighboring anchor node is obtained by using the RSSI ranging model,and the ratio of the distance value and the communication radius is converted into the hop value.Correction factors are introduced,which correct the multi-hop value and the average hop distance value.Finally,the node position calculation problem is transformed into an optimization problem,and the node coordinate value is calculated by lion swarm optimization.Simulation results show that under the condition of fewer anchor nodes,compared with the traditional 3D DV-Hop algorithm,weighted 3D DVHop algorithm,and VNDV-Hop algorithm,the proposed algorithm can improve the positioning accuracy of unknown nodes at the edge and reduce the average positioning error.