Ultra-low-noise Amplifier for Cryocooled SATCOM Receiver

HYPRES has developed and demonstrated a family of novel wideband digital-RF receivers for satellite communication (SATCOM) and other radio frequency communication, signals intelligence and electronic warfare applications. The digital-RF receiver uses superconductor integrated circuits and is mounted on a cryocooler, a reliable refrigerator that achieves cryogenic temperatures of 4 K without the need for any liquid cryogens. The present project focuses on the development of an appropriate cold front-end low-noise amplifier (LNA) for an X-Band SATCOM receiver, and its integration on the same cold platform as that for the digital-RF receiver itself. Both low-power semiconductor amplifiers (based on high-electron-mobility transistors or HEMTs) and superconductor amplifiers (based on Josephson junctions and superconducting quantum inteference devices or SQUIDs) will be comparatively investigated in terms of gain, linearity, noise temperature and power dissipation. We will select and measure the performance of cold HEMT amplifiers in collaboration with researchers at the University of California, Berkeley. The target noise temperature is 5 K or less. Based on these results, an optimized prototype amplifier and receiver system will be designed during the Phase I Option, for fabrication and delivery during Phase II.