乌鲁木齐VLBI站的一种新定标方案  

A new calibration method of the 25 m atenna system at urumqi VLBI station

作　　者：李劲 

机构地区：[1]中国乌鲁木齐天文台,高级工程师830011

出　　处：《宇航计测技术》1997年第3期18-22,共5页Journal of Astronautic Metrology and Measurement

摘　　要：提出了一种利用天线噪声作为冷噪声源进行定标的方案,这套方案在国际和国内的射电天文界是首次提出,与经典的方法不同。其优点是简单易行,准确可靠,定标精度可以达到国家二级标准(约0.5K),尤其是采用这种新方案后,减少了系统中的部件及接口,使系统噪声温度 T_(sys)大大降低(20～30K),系统也更加可靠稳定,是一种切实可行的工程方法。这种方案也可以利用标准射电源和冷空进行定标。In this paper,we proposed a new calibration method of the 25 m atenna system at Urumqi VLBI station.This method is first proposed in radio astronomy field. Atenna noise as cold noise source and analyzer measurment errors of this method are des- cribed.The r.m.s.is within about 0.5 K under conditions of correct operation,and reached to the national second-class standard.We think this new method is simple,flexible and re- liable measurement in engineering,especially in cutting down system interface in order re- duce system temperature(reduce about 20～50 K)and increases system stability.By mak- ing use of standard radio source and sky background,the calibration can be compleled with the same method.

关 键 词：定标 天线噪声 大气噪声 射电天文法 天线 

分 类 号：P111.44[天文地球—天文学]