射电望远镜焦面场分析研究

Analysis and Research on Focal Plane Field of Radio Telescope

射电望远镜的焦面场分析是开展馈源喇叭设计的重要方法,该方法对于性能优越的焦平面阵列设计同样适用。对于给定的射电望远镜系统,主要包括天线口径及焦径比,可以依据焦面场的分析结果来开展相控阵馈源接收机的阵列设计。本文通过在1.25 GHz下结合不同的天线口径、焦径比,以及波束扫描角度,对焦面场进行了相关的分析研究。分析结果显示,焦面场与天线口径没有必然联系,与焦径比成正比,扫描角度越大焦面场畸变越明显且会占据更大的区域。本论文相关的分析研究可为L波段相控阵馈源接收机设计及研制提供参考,尤其是对阵列设计具备较好的指导作用。

Focal plane field analysis of radio telescope is an important method to design feed horn.This method is also suitable for the design of focal plane array with superior performance.For a given radio telescope system,including antenna aperture and focal diameter ratio,the array design of Phased Array Feed receiver can be carried out according to the analysis results of focal plane field.In this paper,the focal plane field is analyzed and studied by combining different antenna aperture,focal diameter ratio and beam scanning angle at 1.25 GHz.The results show that the focal plane field is not necessarily related to the antenna aperture,but directly proportional to the focal diameter ratio.The larger the scanning angle is,the more obvious the focal plane field distortion is and will occupy a larger area.The related analysis and research in this paper can provide reference for the design and development of L-band phased array feed receiver,especially for the array design.