发展空间科学，开展深空探测，是中国航天科技发展的目标。嫦娥工程作为中国开展深空探测的第一步，有着深远的影响。 云南天文台40米射电望远镜是嫦娥工程地面应用系统数据接收分系统的重要组成部分，主要任务是同北京密云50米射电望远镜一起完成探月卫星下传数据的接收、记录和储存，并将数据实时或事后传送到地面应用系统总部。它是地面应用系统与卫星间的传输通道。此外云南天文台40米射电望远镜还与上海（25米）、乌鲁木齐（25米）及北京（50米）组成VLBI(Very Long Baseline Interferometry：甚长基线干涉测量)测轨分系统与中国航天S波段测控网共同完成嫦娥一号卫星的轨道测量任务。本文的第一章进行了详细的介绍。 为了满足任务的需要，首先要保证天线（射电望远镜的机械部分称为天线）控制系统的可靠性和稳定性，由于云南天文台的40米天线是新建立起来的设备，对天线控制系统进行系统的测试与分析就显得尤为重要，本文的第二章进行了详细的介绍。 指向精度是衡量大型射电望远镜的重要性能指标之一。对天线指向误差进行校正，首先要建立指向误差模型，然后根据指向误差模型和观测数据选择合适的数据拟合方法，本文选择最小二乘法拟合出指向误差模型的各个参数，并得出40米天线指向精度。最后分析得出经过指向误差校正后40米射电望远镜指向精度达到指标要求。本文的第三章进行了详细的介绍。
其他摘要
Developing space science and detecting deep space are goals of China-space. China’s Lunar Exploration (CLEP) is the first step to deep space. It has a far-reaching effect in the future. 40m radio telescope in Yunnan observatory is an important part of CLEP, it will be with 50m radio telescope take charge in receiving signal from the Chang’e-1 satellite in the future. Furthermore, 40m radio telescope in Yunnan、25m radio telescope in Shanghai、25m radio telescope in Urumchi and 50m radio telescope in Peking make up of a net of VLBI(Very Large Baseline Interferometry). This method can measure the orbit of Chang’e-1 accurately in the future. Of cause 40m radio telescope also can observe radio source and work for astronomical observation. Hence, firstly we must make sure of 40m radio telescope can run normally and reliably all the time, because of 40m radio telescope has built up just a few days, manipulating and testing this new control system of 40m radio telescope are very important. We will explain detailedly at the second part of this paper. Secondly, since the beamwidth of the parabolic reflector antenna decreases with increasing wavelengths, errors in pointing accuracy assume additional importance. Including 40m, in the third part of this paper we will talk about pointing calibration and give the outcome of pointing calibration for 40m. The conclusion of this experiment is that pointing accuracy of the 40m radio telescope can achieve the observational requirement.
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