Research On High-precision Spot Positioning Technology In Space Laser Communication

Space laser communication is a kind of communication method that uses light as a carrier for information transmission.The advantages such as high transmission rate and good confidentiality make it the hotspot of today's information transmission technology.In laser communication systems,aiming,capturing,and tracking are prerequisites for laser communication and are the guarantee for the establishment of communication links.Spot highprecision detection and positioning is the basis for aiming,capturing and tracking.Improving the spot positioning accuracy has always been an important research issue in laser communication.This article describes the current research status of space laser communication systems at home and abroad,and thoroughly understands the spot location technology.The basic composition and working principle of the spatial laser communication system are explained in detail,and the influence factors of the complex environment of the atmospheric channel on the spot location of the communication terminal are analyzed.At the same time,the influence of three kinds of atmospheric conditions,namely atmospheric scattering attenuation,turbulent flow scintillation,and atmospheric turbulence speckle,on the spot location accuracy analysis,and for the complex and varied factors,the corresponding algorithm is designed and simulated: Under the condition of atmospheric scattering and attenuation,the spot is positioned using the method of fitting the center of gravity,under the condition of turbulent scintillation,an improved method of combining centroid algorithm and edge detection is used to improve the spot positioning accuracy,under the condition of atmospheric turbulence speckle The Canny algorithm is used to detect the edge of the spot,and the center of the spot is located by the Hough transform.Finally,an experimental test system was set up to simulate atmospheric influences and compared with the traditional positioning method and the method of this paper.According to statistical calculation of miss distance data,the mean square value of the localization of the light spot using the traditional centroid algorithm is 0.39,the mean square value of the accuracy of positioning the light spot using the three algorithms studied in this paper is 0.30,0.32,0.29 in sequence.The experimental results show that under the influence of the atmosphere,the algorithm designed in this paper improves the positioning accuracy of the light spot more than the traditional algorithm,and it is helpful for the realization of the laser communication link,improving the communication efficiency,and has certain practical application value.