Recent developments in millimeter-wave receiver have enabled new remote sensing capabilities. MMIC circuits
operating at frequencies as high as 200 GHz have enabled low-cost mass producible integrated receivers suitable for
array applications. We will describe several ground-based demonstrations of this technology including development of
integrated spectral line receivers for atmospheric remote sensing, a synthetic thinned aperture radiometer for atmospheric
sounding and imaging and polarimetric array radiometers for astrophysics applications.
We have developed amplifier based receivers using Indium Phosphide
high electron mobility transistor (HEMT) monolithic microwave
integrated circuit (MMIC) technology. These compact receivers are
designed with atmospheric temperature and humidity sounding
requirements in mind, operating at 100-125 GHz around the 118 GHz
oxygen line, and at 160-185GHz near the 183 GHz water line, with
average noise temperatures of 1600 and 1200K respectively. They are
intended for applications where small volume and power consumption are critical. We will present laboratory data on the noise temperature of these receivers operated at room temperature and preliminary field data.