Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1771714 | Chinese Astronomy and Astrophysics | 2015 | 17 Pages |
Abstract
At first, the receiving system of the Tianma 65m radio telescope (TM65m in brief) and its noise characteristics at the L, S, C, and X four frequency bands are described. Then, a few measuring methods of system noise temperature are discussed, and the major factors affecting the noise temperature measurement are analyzed, including the errors caused by the non-linearity, feed network insertion loss, mismatch, and so on. With the Y-factor method the noise temperature of the noise source calibrated in the laboratory is verified, indicating that its accuracy attains ∼0.2K. Finally, the system noise temperatures actually measured at the four frequency bands and an analysis on the result are given.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Astronomy and Astrophysics
Authors
Wang Jin-qing, Yu Lin-feng, Zhao Rong-bing, Jiang Dong-rong, Lou Fang-xun, Lao Bao-qiang, Li Bing, Dong Jian, Fan Qing-yuan, Qian Zhi-han, Liu Qing-hui, Jiang Yong-bin,