Research On Localization Of Underwater Wireless Sensor Network

Positioning technology is one of the key technologies in underwater wireless sensor network.When the location information of the node is accurately known,the data collected by the sensor node will be effective.Due to the particularity of the water environment,the underwater wireless sensor network has the characteristics of sparse sensor nodes,non-uniform network structure,difficult clock synchronization of nodes,and difficult replacement of nodes and so on.These make it difficult to locate underwater wireless sensor networks.The sparse and uneven structure of nodes in the network will affect the communication coverage of the network,which is the prerequisite for the realization of network node positioning.Underwater sensor nodes are difficult to replace and have limited energy,and low-energy positioning algorithms are enough to make the nodes have higher energy utilization and longer survival times.Mobile anchor node auxiliary positioning can improve the network's communication coverage,but the movement route of the anchor node is very important.RSSI positioning technology does not require node time synchronization and additional hardware equipment,can reduce the energy consumption of node positioning,but is easily affected by the underwater environment to produce ranging errors,resulting in large node positioning errors.This paper focuses on the path planning of the mobile anchor node and the RSSI ranging algorithm,and improves the underwater wireless sensor network positioning algorithm from these two aspects:(1)The topology of the underwater wireless sensor network and the anchor node movement path planning algorithm are studied.In the design of positioning algorithm,the network structure,the number of virtual anchor nodes,the length of anchor node movement path and the energy consumption of positioning are taken into account.A positioning algorithm based on the dynamic planning of anchor node movement path is proposed.The algorithm collects the dynamic information of the network by moving the anchor node to determine the location of the virtual anchor node.Using the ant colony algorithm to get the anchor node movement path.The algorithm guarantees the coverage of network communication and improves the node positioning rate and positioning accuracy.Experimental simulation proves that the location problem caused by the uneven structure of the underwater wireless sensor network and the sparse node has been solved effectively.(2)The sensor node in the underwater wireless sensor network is in three-dimensional space,and the complexity and mobility of water matter in the water environment lead to low accuracy of the ranging algorithm,which affects the positioning accuracy.In this paper,a three-dimensional positioning algorithm for underwater wireless sensor network based on correcting RSSI values is proposed.The ranging algorithm of the underwater sensor node is studied,and the underwater ranging model is established to improve the accuracy of the ranging.The ranging algorithm of the underwater sensor node is studied,and the distance conversion model is established to improve the accuracy of the ranging.At the same time,the position estimation model is proposed,which combines the underwater three-dimensional model with the minimum two-multiplication.The unpositioned node location is estimated based on the distance between the unpositioned node and the anchor node.Experimental simulation proves that the accuracy and accuracy and robustness of the ranging algorithm are improved effectively.