1200 GHz High Spectral Resolution Receiver Front-End of Submillimeter Wave Instrument for JUpiter ICy Moon Explorer: Part I - RF Performance Optimization for Cryogenic Operation

The submillimeter wave instrument is a spectrometer/radiometer instrument on board of JUpiter ICy Moons Explorer mission operating in two submillimeter heterodyne bands around 530 µm (530–625 GHz) and 255 µm (1080–1275 GHz). This article presents the results of acceptance testing and performance optimization carried out on the flight and spare model of the 1200 GHz receiver front-end. The safe operation conditions at 120–150 K ambient temperature, such as maximum authorized input RF power, applied dc bias voltage are determined through the definition of the Schottky junctions dissipated power and current density ranges. A tuning procedure that optimizes the sensitivity of the front-end while keeping it within safe limits at 120–150 K temperature operation is discussed. In part II, we present a detailed analysis of reliability and endurance testing.