The Active Compensation Technique for Large Reflector Antennas Based on Quadratic Curve Fitting  

作　　者：Tian-Xiang Zheng Bin-Bin Xiang Han-Wei Cui Wei Wang Pei-Yuan Lian Shang-Ming Lin Yang Zhang Jian-Ping Zhou Kai Li 

机构地区：[1]School of Mechanical Engineering,Xinjiang University,Urumqi 830017,China [2]School of Mechano-Electronic Engineering,Xidian University,Xi’an 710017,China [3]Xi’an Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi’an 710119,China

出　　处：《Research in Astronomy and Astrophysics》2024年第7期226-234,共9页天文和天体物理学研究（英文版）

基　　金：funded by the National Natural Science Foundation of China(NSFC,grant Nos.12363011,52275270,and 52275269);Natural Science Foundation of Xinjiang Uygur Autonomous Region(No.2023D01C22);the Tianchi Talents Program of Xinjiang,the National Key Basic Research Program of China(No.2021YFC2203501);the Xinjiang Postdoctoral Foundation。

摘　　要：Active reflectors are often used to compensate the surface distortion caused by environmental factors that degrade the electromagnetic performance of large high-frequency reflector antennas.This is crucial for maintaining high gain operation in antennas.A distortion compensation method for the active reflector of a large dual-reflector antenna is proposed.A relationship is established between the surface deformation and the optical path difference for the primary reflector by geometric optics.Subsequently,employing finite element analysis,a polynomial fitting approach is used to describe the impact of adjusting points on the reflector surface based on the coordinates of each node.By standardizing the positions of various panels on the reflector,the fitting ns can be applied to the reflector panels of similar shapes.Then,based on the distribution characteristics of the primary reflector panels,the adjustment equation for the actuators is derived by the influence matrix method.It can be used to determine the adjustment amount of actuators to reduce the rms of the optical path difference.And,the least squares method is employed to resolve the matrix equation.The example of a 110 m aperture dual-reflector antenna is carried out by finite element analysis and the proposed method.The results show that the optical path difference is reduced significantly at various elevation cases,which indicates that the proposed method is effective.

关 键 词：METHODS analytical-Methods numerical-Telescopes 

分 类 号：P111.44[天文地球—天文学]