Radio-telescope receivers are developed to sense very weak astronomical signals. The sensitivity of a radio telescope is inversely proportional to its noise temperature, which is largely dependent on the amount of noise generated in the receiver low-noise amplifier (LNA). In addition, a radio telescope sensitivity is also proportional to its collecting area; however, it is very costly to enhance sensitivity by increasing the collecting area. Given the high costs associated with increasing the collecting area, the development of methods of reducing LNA noise becomes critical to optimizing the operation of radio telescopes. Such LNA-noise reduction techniques must first be verified via laboratory measurements and then subsequently verified using field measurements on the telescope.

中文翻译：

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环境温度和低温下极低噪声放大器的噪声参数测量


射电望远镜接收器的开发是为了感知非常微弱的天文信号。射电望远镜的灵敏度与其噪声温度成反比，这在很大程度上取决于接收器低噪声放大器（LNA）中产生的噪声量。此外，射电望远镜的灵敏度也与其采集面积成正比；然而，通过增加收集面积来提高灵敏度的成本非常高。鉴于增加收集面积的成本很高，开发降低 LNA 噪声的方法对于优化射电望远镜的运行至关重要。这种 LNA 降噪技术必须首先通过实验室测量进行验证，然后使用望远镜的现场测量进行验证。