射电望远镜基于座架温度的热致指向误差建模  

Modeling of Thermally Induced Pointing Error for Radio Telescopes Based on Alidade Temperature

作　　者：涂标 付丽[2,3] 王锦清[2,3] 王旭[1] 周磊[1] 刘庆会[2] TU Biao;FU Li;WANG Jin-qing;WANG Xu;ZHOU Lei;LIU Qing-hui(Chongqing Jiaotong University,School of Civil Engineering,Chongqing 400074,China;Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 200030,China;Key Laboratory of Radio Astronomy,Chinese Academy of Sciences,Nanjing 210008,China)

机构地区：[1]重庆交通大学土木工程学院,重庆400074 [2]中国科学院上海天文台,上海200030 [3]中国科学院射电天文重点实验室,南京210008

出　　处：《天文学进展》2024年第1期149-159,共11页Progress In Astronomy

基　　金：国家重点研发计划(2021YFC2203501);国家自然科学基金(12273097,12002069)。

摘　　要：温度是影响高频大型射电望远镜性能的关键因素之一。以天马望远镜(TMRT)为例,研究了座架节点温度与天线指向之间的关系,提出了基于节点温度的指向误差修正模型构建方法。将指向误差视为座架节点温度的线性组合,以节点的温度灵敏度作为特征条件优化自变量的个数,将北极附近源2344+8226的指向测试结果作为样本集,与自变量简化前后的温度模型的效果进行对比。同时,这两种温度模型也进行了有限元分析验证,模型计算和有限元分析结果都与样本集相吻合。为了验证模型的通用性,对比分析了模型简化前后在4个季度的表现,结果表明简化后的温度模型预测效果更佳。建立的基于节点温度的指向误差修正模型的快速计算结果,也为座架热致指向误差实时修正提供数据支持。Temperature is one of the key factors influencing the performance of large-scale radio telescopes.Taking the Tianma Radio Telescope(TMRT)as an example,this study investigates the relationship between the temperature of the alidade’s nodes and antenna pointing accuracy.A method is proposed for constructing a correction model for pointing errors based on node temperatures.The pointing error is treated as a linear combination of the alidade’s node temperatures.The number of independent variables is optimized using the temperature sensitivity of the nodes as feature conditions.The pointing test results of the source 2344+8226 near the North Pole are used as the sample set to compare the effectiveness of the temperature model before and after variable simplification.Both the model calculations and finite element analysis validate the two temperature models,which align with the sample set.Furthermore,to assess model generalization,the performance of the models is compared across four seasons before and after simplification.The results indicate that the simplified temperature model offers improved predictive accuracy.The established node temperature-based pointing error correction model’s rapid calculation outcomes provide data for real-time mitigation of thermally induced pointing errors in the mount.

关 键 词：射电望远镜 温度传感器 指向误差 温度模型 

分 类 号：P111.44[天文地球—天文学]