Calibration and Validation Plan for the NASA-ISRO Synthetic Aperture Radar (NISAR)

Abstract

The NASA ISRO SAR mission (NISAR) will be a dedicated U.S. and Indian SAR mission for studying hazards and global environmental change. Operating at both L-band and S-band wavelengths, NISAR will acquire data globally to address three mission science themes: The Earth’s surface and interior; the Earth’s cryosphere; and the Earth’s ecosystems. NISAR is planned for launch in late 2021 or early 2022. The L-band SAR will have several modes up to and including fully polarimetric modes with most modes supporting a split spectrum to facilitate the correction of ionospheric delays; NISAR will support selectable bandwidths between 5 MHz and 80 MHz. The mission will be capable of acquiring SAR data every 12-day repeat orbit for both ascending and descending orbit directions over most if not all of the Earth’s land surface during the nominal 3-year mission duration. Orbit tube repeatability for this left-looking SAR mission will be better than 500 m. In addition to the calibration of the sensor data, NISAR will have 13 science measurement requirements that will be validated after its launch.