Description: This proposed Phase II SBIR would realize a prototype of an offset Gregorian antenna design that will be delivered to NASA for integration in the D3R GPM ground validation radar system, for which RSS is currently fabricating the radar transceiver through a Phase III project. During the Phase I effort for this antenna system, Remote Sensing Solutions developed a design for a novel dual-wavelength Ku/Ka-band radar remote sensing antenna system with high integrated cross-polarization isolation (> 30 dB) and low sidelobes (< -25 dB). The design provides high gain (< 1 deg beamwidth) and matched antenna patterns in a rugged mechanical configuration that is transportable in a standard sea-container. The primary innovations realized in the Phase I design that would be implemented in the Phase II effort include: an ultra-low cross-pol reflector, a rugged compact feed with very low cross-polarization supporting multiple polarizations at Ku and Ka-band and a robust mechanical structure to meet the antenna electrical tolerances over a wide range of environmental conditions.

Benefits: The technology developed will benefit the greater weather research community by allowing weather radar systems to more precisely quantify precipitation. Adapting the technology to other radar wavelengths in future efforts will also allow Remote Sensing Solutions to market to the operational weather research community using long and medium range weather radars.

The proposed Phase II effort will develop and demonstrate the critical technologies required to achieve a dual polarized, dual wavelength antenna capable of providing accurate, quantitative measurements of precipitation and addressing NASA's critical needs with regards to GPM and precipitation measurements, and supporting research in cloud formation and in precipitation initiation that would benefit the NASA ACE program. CloudSat follow-on missions and other future missions focusing on Earth Science will benefit from this antenna's unique ability to ensure accurate measurement of precipitation and cloud properties.