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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Heterodyne efficiency is reduced by aberration of receiving antenna for space coherent optical communication.

空间相干光通信中接收天线像差会使光外差效率下降。

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The radiating element of array antenna is air dielectric microstrip patch antenna, which has high efficiency, and the feed network is low loss air strip, which can reduce the loss of the feed line.

阵列天线辐射单元采用空气介质的微带贴片天线，辐射效率高；阵列天线的馈线网络采用低损耗的空气带状线形式，降低了馈线损耗。

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The transfer of radio signals to and from the antenna and the radio receiver and transmitters, and the efficiency with which that is accomplished determines how well the device will perform.

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