射电天文研究组知识库

为得到更高质量的观测数据,研发了高效的数字分析终端。首先采用基于捷变收发方案的接收机设计方案,模拟前端电路在程序控制下改变本振频率和滤波器带宽,实现高Q值的可编程滤波器,以选取6 GHz带内200 kHz～56 MHz的任意窄带信号;然后通过混合编程调用比值校正算法实现谱线频率在观测中的实时定标;最终研发了射电天文谱线观测及频率定标系统。经实验和实测分析表明,该系统不仅能在云南天文台40 m望远镜下进行高分辨率的谱线观测,还能做到谱线频率的实时定标。

An efficient digital analysis terminal is developed in this paper to help radio astronomers obtain observed data with higher quality in terms of observation and science. In this paper, a receiver design scheme based on the agile transceiving scheme is adopted. The analog front⁃end circuit can change the local oscillator frequency and filter bandwidth under the program control, and a programmable filter with high Q value is realized to select any narrowband signal from 200 kHz to 56 MHz within 6 GHz band. And then, hybrid programming is used to invoke the ratio correction algorithm to realize the real⁃time calibration of spectral line frequency in observation. Finally, a radio astronomy spectral line observation and frequency calibration system is developed. Experimental and measurement analysis show that the proposed system can not only perform high ⁃ resolution spectral line observation with the Yunnan Observatories′ 40⁃meter telescope, but also fulfill real⁃time calibration of spectral line frequency.