UAVSAR Active Electronically-Scanned Array

The Uninhabited Airborne Vehicle Synthetic Aperture Radar (UAVSAR) is an L-band (1.2-1.3 GHz) repeat pass, interferometric synthetic aperture radar (InSAR) used for Earth science applications. Using complex radar images collected during separate passes on time scales of hours to years, changes in surface topography can be measured. Due to variations in aircraft attitude between passes, antenna beam steering is required to replicate the radar look angle from pass-to-pass. This paper describes an Active Electronically Scanned Array (AESA) that provides beam steering capability in the antenna azimuth plane. The array contains 24 transmit/receive modules generating approximately 2800 W of radiated power and is capable of pulse-to-pulse beam steering and polarization agility. Designed for high reliability as well as serviceability, all array electronics are contained in single 178cm×62cm×12cm air-cooled panel suitable for operation up 60,000 ft altitude.