射电天文研究室知识库

基于新疆110m射电望远镜预研项目、南山天线改造计划和国家对航天领域的战略需求,对大型卡氏天线主面板变形的副面实时补偿作了深入研究。简单介绍了副面补偿的理论模型并用静力分析法得出若干特殊仰角下的调整量,进而运用MATLAB对调整量进行了高精度的数据拟合。给出了线性最小二乘法和正交多项式最小二乘法2种拟合方法拟合模型方程,通过误差分析从不同方面对比了拟合方法的效果,在阶数为4、精确至小数点后15位时,2种拟合方法的误差差值数量级为10-13 mm,且小于零。最终选择并应用精度更高的正交多项式最小二乘拟合方法在特定的俯仰角度范围内生成了部分调整量数据,为副反射面在任意俯仰角下的补偿过程创造了条件,满足了天文观测和航天深空探测对数据准确性和系统可靠性的要求,具有一定的实用性。

Based on the rapidly progress of the Xinjiang 110m radio telescope project, Nanshan antenna reform programme and national strategic demand for aerospace development, this paper makes a thorough study for the real-time compensation of the sub-reflector for the deformation of the large antenna's main panel. First, it presents a brief introduction to the theoretical model of sub-reflector compensation and an analysis of adjustments under certain special elevations. Then it realizes high-precision data fit using MATLAB because of its powerful numerical calculation. This paper gives two different data fit methods and model equations and compares the effects of the tow fit methods from different aspects by detailed error analysis. When the fit order is 4 and computing to 15 decimal places, it calculates the erro of the difference between these tow data fit methods: the value is negative and the magnitude is 10^(-13) mm. Finally, the paper chooses the higher precision fitting method whose absolute error is minuend and uses this method to generate a partial adjustment database in the range of some special angels in order to create conditions for the entire sub-reflector compensation process which satisfies the requirements for astronomical observations and deep-space exploration for data accuracy and system reliability. The specific technology is believed to possess certain general value for applicability.