Digital calibration system for the proposed NISAR (NASA/ISRO) mission

The Synthetic Aperture Radar (SAR) instrument for the proposed NASA/ISRO mission would utilize a distributed architecture dubbed SweepSAR. This real-time On-orbit digital beamforming, combined with lightweight, large aperture reflectors, promises significant increases in instrument capability for solid earth and biomass remote sensing. These new instrument concepts require new methods for calibrating the multiple channels, which are combined on-board, in real-time. The benefit of this effort is that it enables a new class of lightweight radar architecture, Digital Beamforming with SweepSAR, providing significantly larger swath coverage than conventional SAR architectures for reduced mass and cost.