Science

The HIAPER cloud radar (HCR) is an airborne, polarimetric, millimeter-wavelength radar that serves the atmospheric science community by providing cloud remote sensing capabilities to the NSF/NCAR G-V (HIAPER) aircraft.

HCR precisely detects drizzle, and thin ice and liquid clouds, estimates their microphysical and radiative properties and takes detailed wind measurements. It can also distinguish between ice, water, and super-cooled water droplets. Data collected by the HCR sensors offer unique observations on the formation and evolution of clouds that can provide critical understanding about the effects of clouds on global and regional climate.

Technical description

In a pod-based design a single lens antenna is used for both transmit and reception. The transceiver uses a two-stage up and down conversion super-heterodyne design. The transmit waveform, from a waveform generator, passes through the two-stage up-conversion to the transmit frequency 94.40625 GHz. It is then amplified by an extended interaction klystron amplifier (EIKA) to 1.6 kW peak power. System performance on transmit and receive paths are closely monitored using a coupler and a noise source. Raw in-phase and quadrature information are archived in HCR.