Research On Wireless Sensor Network Localization Algorithm Based On DV-Hop

In wireless sensor networks,the application environment is complicated,the sensor nodes are randomly deployed nodes,only the specific position,there is only research on node information value of the data,the function of the management and maintenance of nodes and network topology control system can be realized effectively,so positioning plays a vital role in the application of wireless in wireless sensor networks.At present,the researchers put forward the control algorithm by all kinds of conditions in practical application,so the design of long service life,maintenance configuration of low cost,low energy consumption,node localization algorithm with high accuracy,is an important research direction in wireless sensor network.The localization algorithm of wireless sensor networks can be divided into two types: ranging(range-based)positioning and no ranging(range-free)positioning,depending on whether the measurement distance is measured.Need localization algorithms usually require ranging distance or angle between the measurement node and neighbor node information without location algorithm through single hop or multi hop routing information exchange,the last to be measured is calculated according to the estimated value of node location.DV-Hop algorithm is one of the ranging and localization algorithms.Because of its low overall cost and high positioning accuracy,the algorithm has been widely used.This paper focuses on the DV-Hop algorithm.In the DV-Hop algorithm,when the number of hops is calculated,both the distance and the number of hops are recorded as 1 hops,which is prone to errors,Firstly,the ideal hop number is defined in the hop count phase.The deviation factor and jump distance correction system are adopted to correct the jump number of the anchor node and the unknown node respectively;Secondly,in the localization stage,need to consider the anchor nodes communicating with the network,affect the anchor node weights by the average distance per hop error on the path and the number of hops,using the error value and the normalized weighted hop value of anchor nodes and unknown nodes choose the average hop anchor node weighted coefficient of the distance as the average hop distance between nodes,the estimated distance is more accurate;Finally,in the coordinate estimation stage,according to the number of anchor nodes around the nodes,the centroid coordinates algorithm and weighted least square method are used to estimate the node coordinates in different ways.Through the improvement of hop number,average hop distance and node coordinate calculation method in DV-Hop positioning algorithm,the deviation caused by calculation is further reduced.Using MATLAB software to verify the two algorithms,in the same verification environment simulation,without adding additional hardware devices,the improved DV-Hop algorithm is higher than the original positioning accuracy,the error is relatively small.