射电天文研究室知识库

大口径射电望远镜的表面精度是影响天线性能的重要因素之一,受面板加工、安装以及重力、温度和风载的影响,极大地限制了天线的观测效率.基于较副面六联杆更加精确可控的主动面技术,首次采用泽尼克(Zernike)多项式表示连续变化的主动形变相位因子,通过调整主动面获取远场幅值,即可检测表面误差.通过建立数值仿真模型,计算了任意表面形变的恢复误差,并研究了在多种连续主动面变化下的表面形变恢复效果.结果表明此方法可以稳定精准地检测表面形变,从而有效提高射电望远镜的观测效率.

The surface accuracy of a large reflector radio telescope is one of the important factors influencing the performance of the antenna. The effects of panel processing, installation, as well as gravity, temperature, and wind load, will greatly limit the observation efficiency of the antenna. Focused on the technology of active surface which is more accurately controllable than the minor reflector surface of six-pole, the continuous distribution of active deformation phase factor described by Zernike polynomials is adopted for the first time. Only getting the far field amplitude through adjusting the active surface, the surface error can be detected. By building the models of numerical simulation, the retrieval error of arbitrary surface deformation is calculated, and the retrieval results of surface deformation in a variety of continuous active surface deformation is also studied. It is indicated that this method can stably and accurately detect surface deformation, and can also improve the efficiency of radio telescope observations effectively.