德令哈13.7 m望远镜接收机抗射频干扰研究

Research on Receiver Anti-RFI of Delingha 13.7 m Telescope

在天文观测中,射频干扰会造成假谱,降低数据的可靠性和有效性.射频干扰消减旨在减少干扰信号对射电天文观测的影响,包含器件方面的技术革新和数据处理领域的方法研究.针对德令哈13.7m望远镜接收机中频部分引入的射频干扰,通过优化中频器件的抗射频干扰能力,提高了接收机的整体抗射频干扰能力,以主动消除方法来减少射频干扰耦合到接收机内部.分析了接收机干扰的传输路径,提出了器件射频干扰的直接耦合系数和器件射频干扰的系统耦合系数的概念,为定位干扰敏感器件并量化干扰引入比重提供了基础.经过抗射频干扰优化后,接收机抗干扰能力改善30dB左右,望远镜的天文观测效率提高10%以上.

In astronomical observations, the radio frequency interference(RFI) will cause pseudo spectra and reduce the reliability and validity of observational data. The RFI mitigation which includes many technical means of devices and methods of data processing aims at reducing the influence of RFI on radio astronomical observations.Various efforts were made to improve the anti-RFI capability of the multibeam receiver(Superconducting Spectroscopic Array Receiver, SSAR) of Delingha 13.7 m telescope.The interference transmission path was analyzed. The concepts of device RFI direct coupling coefficient and device RFI system coupling coefficient are proposed. The proportions of interference introduced in receiver system by devices were quantified,and the interference-susceptible devices in the system were located. After the anti-RFI treatment of the interference-susceptible devices, the anti-RFI capability of the receiver system is improved by 30 dB in average, and the astronomical observation efficiency of the telescope is increased by more than 10%.