The Opto-mechanical Design And Gravity-deformation Fem Analysis On Optical Telescope In Inter-satellite Optical Communication System

Inter-satellite Optical Communications, is a kind of communication form whichused free space as a channel, used laser as the information carrier, and achieved thecommunication purposes by transmiting and receiving laser signal.Compared to themature and widely used RF space communication system,Inter-satellite OpticalCommunications has a very obvious advantage,but it also has technical difficulties tobe overcome in the implementation process, including high precision optical system,complex target, acquisition, tracking (PAT) system design and so on.In order to guarantee the satellite optical communication system can work wellunder the extremely harsh environment conditions in space, and meet the technicalindex of high precision, it requires optical components and mechanical structure ofoptical antenna telescope must have sufficient stability and reliability. In the designprocess of optical antenna telescope satellite optical communication terminal’s keycomponent,we should consider about various factors in order to avoid or to reduce theimpact on the communication system caused by deformation of optical elements andmechanical structure under space’s working condition.This is a comprehensive systemof the design process,and it’s also an iterative, constantly optimizing process.The object of this study is modified R-C telescope. As the main opticalcomponents of satellite optical communication terminal, the design,analysis andresearch on primary mirror, second mirror and truss of the telescope optical antennaplays an important role on optical system’s stability and reliability.So it is necessary toconduct optical design, mechanical structure design to telescope optical antenna，and to analysis finite element for the deformation caused by its self gravity.The research on this paper mainly includes the following three aspects:(1) The optical design and simulation of optical antenna telescope. Combiningsatellite pass light’s optical system parameters, based on the three class aberration theoryof two surface pattern R-C telescope, we designed the two mirror telescope opticalantenna which meet requirements in different pupil diameter.(2) Optical antenna telescope’s mechanical structure design and finite elementcalculation caused by weight deformation; Based on optical antenna telescope designparameters, we confirmed the mechanical support structure of primary mirror, secondmirror and the connected truss.We also calculated each component’s gravitydeformation of optical axis under the vertical condition with ANSYS software.(3) Evaluation on image quality of optical antenna telescope’s optical properties.Based on the calculation result of finite element analysis of gravity deformation, wemainly analyzed three optical indicators of the optical antenna system’s wavefront, circle of confusion and MTF.