4-12 GHz and 25-34 GHz cryogenic MHEMT MMIC low noise amplifiers for radio astronomy

Abstract

MMIC Broadband Low Noise Amplifiers (LNA) for radio astronomy applications with 100 nm GaAs metamorphic High Electron Mobility Transistor (mHEMT) process have been developed. Cryogenic performance of a 4–12 GHz and a 25–34 GHz LNAs is presented. The 4–12 GHz LNA cooled at 15 K exhibits an associated gain of 31.5 dB ± 1.8 dB and average noise temperature of 5.3 K with a low power dissipation of 8 mW. Cooled to 15 K the 25–34 GHz amplifier has demonstrated a flat gain of 24.2 dB ± 0.4 dB with 15.2 K average noise temperature, and a very low power dissipation of 2.8 mW on chip. The mHEMT based LNA MMICs have demonstrated excellent noise characteristics at cryogenic temperatures for their use in radio astronomy applications.