Antenna system noise temperature and antenna efficiency are the most important items in the system debugging and checking before the VLBI observation.

在流动vlbi的观测试验中，天线系统噪声温度和天线效率是观测前系统调试和检测的两项重要内容。

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The conversion loss and noise temperature of mixers is determined by changing the IF noise temperature so as to change the noise temperature of the receiver system.

混频器的变频损耗和噪声温度的测量可以用改变中频部分的噪声温度使接收机的系统噪声温度变化来加以确定。

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After the bandwidth and temperature, the remaining factor in determining the system noise is the effective source resistance.

讨论了带宽和温度以后，决定系统噪声的另一个因素就是等效源电阻。

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