Research Of DV-Hop Location Algorithm Based On Jaccard Similarity Coefficient And Cooperative Localization

The DV-Hop positioning algorithm without ranging is a widely used wireless sensor network positioning technology.In the positioning process,the information broadcasting process of the anchor node in the network is used for node positioning,which can effectively save cost and save energy.In order to reduce the positioning error of DV-Hop localization algorithm,this paper proposes an improved algorithm to analyze the possible errors of DV-hop algorithm in three positioning stages,which can be realized without increasing hardware cost and saving network energy consumption make more accurate positioning.This paper's main research contents are as follow:(1)The DV-Hop algorithm has errors in ranging,and its accumulated error will become larger and larger as the number of hops increases.The Jaccard Similarity Coefficient can not only compare the similarity between the two sets,but also distinguish the degree of difference between the sets.In order to calculate the more accurate average hop distance in the DV-Hop algorithm,an Improved algorithm based on Jaccard Similarity Coefficient which called Jaccard DV-Hop(JDV-Hop)is proposed.in the first stage of the classical DV-Hop algorithm,the Jaccard Similarity Coefficient is introduced into the DV-hop algorithm.Within the communication radius between neighbor nodes,the Jaccard Coefficient is used as a hop correction factor to assign the number of nodes in the intersection area to the neighbor.The one-hop distance between nodes is modified to further refine the estimated hop count of the node to its neighbor nodes and obtain a more accurate one-hop distance.(2)In the DV-Hop algorithm,the unknown node uses the product of the minimum hop count of the anchor node and the average hop distance of the anchor node closest to it as the distance between it and the anchor node,so the average hop distance is not accurate.The calculation of the node distance produces a large error.In addition,due to the network topology and network connectivity,the unknown node selects the average hop distance of the anchor node closest to itself as its average hop distance.However,Average hop distance.Therefore,based on the modified hop count using the Jaccard coefficient,the finite difference error of the DDV-Hop localization algorithm is introduced in the second stage of the classical DV-Hop algorithm to improve the calculation of the average hop distance.Average hop distance for more accurate average hop calculation.(3)When the DV-Hop algorithm finds the location of the unknown node,at least the distance information of more than three anchor nodes needs to be known.Therefore,the optimal selection of the anchor node is extremely important for the coordinate determination of the unknown node.This paper proposes a cooperative positioning algorithm.The basic idea of the cooperative positioning algorithm is to conditionally upgrade the positioned nodes to anchor nodes and continue to locate other unknown nodes.The positioning accuracy of the unknown node upgraded to the anchor node must be high enough.Otherwise,although the overall energy consumption of the wireless sensor network can be reduced,using its inaccurate position to estimate the position of other unknown nodes again will result in a larger Error.In summary,the paper mainly uses the no-range positioning algorithm of wireless sensor networks as the research background,combined with the basic features of the classical DV-Hop positioning algorithm and some specific improved algorithms.This paper proposes an improved algorithm based on the Jaccard Similarity Coefficient and cooperative localization.Through MATLAB software simulation experiments,the algorithm and the classic DV-Hop positioning algorithm and some other improved algorithms for positioning accuracy,energy consumption and stability comparison.The simulation results show that the improved algorithm can not only improve the node positioning accuracy,but also reduce the positioning error without increasing the hardware cost and energy consumption.This paper provides a global optimization scheme based on the optimal selection of anchor nodes for the calculation of unknown node coordinates.