Research Of Data Collection And Charging Strategy Based On Mobile Edge Devices In Underwater Sensor Networks

Wireless Sensor Networks(WSNs)have received extensive attention in production applications and academic researches.With people's attention to marine resources,wireless Sensor Networks have been widely used in underwater environment,marine ecological protection,offshore oil development,underwater navigation,etc.Therefore,researchers proposed the concept of Underwater Wireless Sensor Networks(UWSNs).UWSNs has the ability to store,calculate and share data,just like WSNs.However,the underwater sensor network is deployed in the underwater three-dimensional space,and the data transmission mode is different.The data transmission mode of underwater sensor network leads to hot spots.Besides,the energy of underwater sensor nodes is limited and it is difficult to replace batteries.The problem of energy consumption in underwater sensor networks has attracted the attention of researchers.In this paper,energy consumption in underwater sensor networks is studied,and some urgent problems are found:1)Existing data collection methods have serious problems of energy consumption.Sensors in underwater sensor networks usually transmit sensing data through acoustic wave.However,a large amount of energy is needed to transmit data,and due to the limited transmission distance,generally underwater sensor nodes need to transmit data through multi-hop routing,which causes hot spots.2)In the current underwater sensor networks,it is difficult to replenish the energy of sensor nodes.Most of the existing underwater sensor networks focus on data collection,but few on energy supplement of sensor nodes.In UWSNs,energy consumption is required for sensor nodes to work,and in the underwater environment,it is difficult for nodes to replace batteries.Therefore,it is difficult to significantly improve the network life cycle.3)How to coordinate data collection and charging in the underwater sensor networks.With the development of underwater sensor networks datacollection and underwater sensor charging technology,the research on charging strategy is increasing.For some UWSNs that require data collection and charging at the same time,how to coordinate data collection and charging is an urgent problem to be solved.A viable solution is to deploy one or more edge mobile devices in the UWSNs to participate in or assist in data collection and charging.Mobile edge devices,which are closer to the underlying network,have the ability to compute,store,and share data.Therefore,this thesis proposes the methods to provide efficient data collection and charging service for the underwater sensor network based on the mobile edge devices to assist the work of the underwater sensor network.In this thesis,mobile edge devices are designed into two categories,one with the function of collecting data,and the other with the function of charging.The main research work is as follows:1)Solving the problem of serious energy consumption in the data collection method of underwater sensor network.Underwater sensor nodes are clustered into multiple clusters.The edge mobile device is used to collect the data of cluster head node.2)Solving the problem that it is difficult to replenish the energy of sensor nodes in the underwater sensor network.The surface base station is used as the charging service station and the edge mobile device is used as the mobile charging platform.The edge mobile device moves to the node which it needs to be charged and charges the node.This cycle is used to replenish energy for underwater sensor nodes.3)Solving the problem of how to coordinate data collection and charging in the underwater sensor network.Divide the network into sub-regions,and deploy a edge mobile device,which is responsible for collecting data.Moreover,deploy a mobile edge device in each sub-region to charge for underwater sensor nodes that are within the area.To sum up,in view of the shortcomings of the existing data collection and charging in the underwater sensor network,this thesis designs a data and charging framework based on edge mobile devices.Based on the framework,the functions of data collection and charging of underwater sensor nodes are realized.The edge mobile device not only achieves efficient data collection and reduces node energy consumption,but also realizes the service of charging sensor nodes.