1.35-2.0 GHz Low Noise Amplifier Based on GaAs Transistor

Low Noise Amplifier (LNA) is a key device in the receiving system in radio astronomy. The noise performance of LNA dominated the system noise temperature and the ability of radio telescope to detect extremely weak signal. In this paper, we designed an LNA based on GaAs process PHEMT ATF-54143. This LNA used 2-stage transistors topology circuit and was supplied by single voltage 5 V. Measured results show hat in its working range from 1.35 GHz to 2.0 GHz, the input loss is better than -10 dB with a typical noise temperature 35 K. It provides a typical gain of 28 dB and the 1 dB-compression point is at -13 dBm. This amplifier can be used in radio telescope receivers for the observation of neutral hydrogen, pulsars and hydroxyl groups in radio astronomy, as well as in radio environment monitoring systems.