Research On Topology Construction And Repair Algorithm Of Free Space Optical Network

As the Wireless Sensor Networks is widely used and the Free Space Optical Communication,also known as wireless optical communication,has high bandwidth,large capacity,high security,unauthorized spectrum,flexible installation,low cost and other advantages.Free Space Optical Sensor Network which has both advantage has developed rapidly.Free Space Optical Sensor Network is widely used in Metropolitan Area Network expansion,disaster emergency communications,optical fiber backup,cellular return network,quantum communications and military secure communications and other fields.However,when Free Space Optical Sensor Network is communicating,the communication quality drops or even the link is interrupted due to the influence of atmosphere and the aim of the node.Meanwhile,the node has limited energy.Therefore,it is an important direction of Free Space Optical Sensor Network research to improve the communication quality of Free Space Optical Sensor Network and extend the network survival time.At the same time,when some nodes of Free Space Optical Sensor Network fail,it will cause some areas of the network to fail,so the repair of Free Space Optical Sensor Network topology is also important.Firstly,the basic principle and key technologies of Free Space Optical Communication system are introduced.According to the attenuation of different emission wavelengths under the weather changes,and the differences of different wavelengths in the safety of human eyes,the emission wavelength of this paper is determined.Finally,the weakening of the system caused by the atmosphere and noise is briefly analyzed,which provides a basis for the subsequent algorithm research and the quantitative analysis of simulation.Then,considering communication quality and energy,the link reliability model is established by combining the link received optical signal and the probability of interruption.Search for the distance threshold of direct transmission or relay based on the model,and then the cluster topology is established according to the network energy consumption.The constructed Free Space Optical Sensor Network topology link is more reliable,and the life of Free Space Optical Sensor Network is effectively extended.Finally,Aiming at the problem of Free Space Optical Sensor Network topology failure,the coverage status is divided,and different types of failure nodes are classified and repaired.The failure nodes are non-relay nodes,the geometric calculation method is used to locate the repair nodes.The failure node is the relay node,the comprehensive evaluation model of coverage energy consumption is established,and the repair node position is found according to the established model.The repaired network can not only resume normal operation,but also save the energy consumption of relay nodes and prolong the life of the network.