Ku波段接收机噪声温度测试及分析  

Measurement and Analysis of Noise Temperature for Ku-band Receiver

作　　者：王凯[1,2] 陈卯蒸[1,2] 李笑飞[1,2] 李健[1,2] 项斌斌[1,2] 闫浩[1,2] 王洋[1,2] WANG Kai;CHEN Mao-zheng;LI Xiao-fei;LI Jian;XIANG Bin-bin;YAN Hao;WANG Yang(Xinjiang Astronomical Observatory,Chinese Academy of Sciences,Urumqi 830011,China;Key Laboratory of Radio Astronomy,Chinese Academy of Sciences,Nanjing 210008,China)

机构地区：[1]中国科学院新疆天文台,新疆乌鲁木齐830011 [2]中国科学院射电天文重点实验室,江苏南京210008

出　　处：《电子机械工程》2018年第6期13-16,21,共5页Electro-Mechanical Engineering

基　　金：国家重点基础研究发展计划(973计划)(2015CB857100);国家自然科学基金资助项目(11603064;U1431230);中国科学院"西部之光"人才培养引进计划(2017-XBQNXZ-B-021);中国科学院天文台站设备更新及重大仪器设备运行专项经费资助项目

摘　　要：微波接收机是射电望远镜中专门用于接收射电信号的设备,接收机的噪声温度是检验其灵敏度的重要指标。经典的接收机噪声温度测试方法是冷热负载法,但该方法不能在观测中随时进行,且受制于接收机尺寸,而斩波轮法用来自冷空的辐射代替不易实现的冷负载,在测试中仅需使用常温黑体。文中搭建了简易的Ku波段常温接收机,使用上述2种方法分别测试该接收机的噪声温度。通过选用不同规格的常温黑体及减小冷热负载之间的温度差来检验冷热负载法测试的不确定性,再对采用冷热负载法确定的最终噪声温度与采用斩波轮法得到的测试结果进行对比,最终确定在晴好的夜间条件下,斩波轮法可以满足Ku波段接收机噪声温度的测试需求。The microwave receiver is special equipment of the radio telescope to receive radio signals and its noise temperature is an important parameter to test the sensitivity.The classic measurement method for noise temperature of receiver,namely the cold and hot load method,can’t be carried out at any time during the observation and is subject to the size of the receiver,while the chopper wheel method uses radiation from the sky to replace the cold load which is difficult to realize and only normal temperature blackbody is enough in test.A simple Ku-band receiver under room temperature is set up and its noise temperature is measured by these two methods in this paper.Two kinds of blackbody under room temperature are selected and the temperature difference between cold and hot load is shortened to test the uncertainty of the cold and hot load method.Then the results of noise temperature measured by cold and hot load method are compared with that measured by chopper wheel method.The comparison result confirms that the chopper wheel method can satisfy the normal noise temperature measurement requirements of the Ku-band receiver in fine weather conditions at night.

关 键 词：微波接收机 Y因子 斩波轮 噪声温度 误差 

分 类 号：TN85[电子电信—信息与通信工程]