A Compact 183-GHz Radiometer for Water Vapor and Liquid Water Sensing

ProSensing Inc. has developed a G-band (183 GHz) water vapor radiometer (GVR) for long-term unattended measurements of low concentrations of atmospheric water vapor and liquid water. Precipitable water vapor (PWV) and liquid water path (LWP) are estimated from zenith brightness temperatures measured using four double-sideband receiver channels, which are centered at 183.31 1, 183.31 3, 183.31 7, and 183.31 14 GHz. A prototype ground-based version of the instrument was deployed at the Department of Energy Atmospheric Radiation Measurement program's North Slope of Alaska site near Barrow, AK, in April 2005, where it collected data continuously for one year. This paper presents design details, laboratory test results, and examples of retrieved PWV and LWP from measured brightness temperature data.