Miniature low noise G-band I-Q receiver

Weather forecasting, hurricane tracking and atmospheric science applications depend on humidity sounding of atmosphere. Current instruments provide these measurements from ground based, airborne and LEO satellites by measuring radiometric temperature on the flanks of the 183 GHz water vapor line. We have developed miniature low noise receivers that will enable these measurements from a geostationary thinned array sounder. This geostationary instrument is based on hundreds of low noise receivers that convert the 180 GHz signal directly to baseband in-phase and in-quadrature signals for digitization and correlation. The developed receivers provided a noise temperature of 450 K from 165 to 183 GHz (NF=4.1 dB) and had a mass of 3 g while consuming 24 mW of power. These are the most sensitive broadband I-Q receivers at this frequency range that operate at room temperature, and are significantly lower in mass and power consumption than previously reported receivers.