Research On Routing Algorithms For Underwater Optical Wireless Networks Based On Energy Balance

It is well known that there are various kinds of natural resources in the ocean.In recent years,the demand for the development and utilization of marine resources has been increasing,and the exploration of marine resources is inseparable from the support of underwater sensor network(USN)technology.At present,the underwater acoustic communication is mainly used for the information transmission in underwater sensor networks.However,due to the technical limitations of underwater acoustic communication,such as low transmission rate,narrow available bandwidth and slow propagation speed,there exist many problems in underwater sensor networks,such as large end-to-end delay,high energy consumption and short life time.Therefore,in recent years,the underwater optical communication based on blue/green low-loss windows has attracted much attention.At the same time,the routing technology of underwater optical sensor networks has become a research hotspot.Due to the complexity of underwater environment,the traditional routing protocols of terrestrial sensor networks cannot be directly applied to underwater optical sensor networks.Therefore,this thesis mainly focuses on the research of routing mechanism of underwater optical wireless sensor networks.The main contributions are as follows.(1)The network structure,channel transmission model and energy consumption model for underwater optical wireless sensor networks are given.In addition,the channel energy consumption variation with transmission distance,data transmission rate and average packet size under different water quality conditions are simulated and analysed.(2)A dynamic threshold adjustment routing(DTAR)algorithm based on the water depth information has been proposed.The algorithm can well deal with routing holes in an underwater optical wireless network through the threshold adjustment strategy.The simulation illustrates that DTAR algorithm can improve the success rate of packet transmission and reduce network energy consumption,and thereby improve network reliability and prolong the network lifetime.(3)An energy balanced routing(EBR)algorithm based on the grid partitioning network has been proposed.The algorithm can balance network energy well through the strategy of grid partitioning.The simulation results show that the EBR algorithm can improve thebalance of network energy consumption,effectively delay the emergence of energy holes and improve the lifetime of the network compared with existing algorithms in the literatures.