A cryogenic ultra-wideband low-noise amplifier for radio astronomy

The next-generation radio telescopes require front-end modules with ultra-low-noise and a wider frequency range for enhanced diversity in receiver designs, thus boosting the efficiency and sensitivity of astronomical observations. This paper designs and implements an ultra-wideband cryogenic MMIC (monolithic microwave integrated circuit) low-noise amplifier with a frequency range of 0.3–15 GHz based on GaAs pHEMT technology. After measurement under both room-temperature (290 K) and cryogenic (25 K) conditions, the packaged amplifier module exhibits a minimum noise temperature of 10 K, with an average noise temperature of 20 K in the 0.3–10 GHz range and an average gain performance greater than 35 dB within the operating frequency band. The measured results demonstrate its practicality at cryogenic, making it qualified to serve as a front-end module for the receivers, and providing a solid experimental foundation for further research and development.