NISAR ISRO science data processing and products

Abstract

NASA-ISRO Synthetic Aperture Radar (NISAR) is a Dual Frequency (L & S band) mission which will be operating in SweepSAR mode. As compared to traditional SAR imaging modes in which Swath and resolution are at trade-off, SweepSAR imaging concept can acquire data over large swath (240 Km) without compromising azimuth resolution (6m approximately). NISAR L-band & S-band sensors will be developed by JPL-NASA and ISRO respectively. NISAR science data will be downloaded at both NASA and ISRO ground stations. SAC-ISRO will develop the SAR processor for both L & S band data to generate products in compliance with science requirements. Moreover, JPL will develop L-band SAR processor and all data products will be available to users. Distributed data processing architecture will be used for handling large volume of data resulting from moderate resolution and larger swath in SweepSAR mode. Data products will be available in multiple processing levels like raw signal products, signal processed single-look and multi-look products, ground range products and Geo-Referenced products in HDF5 & GeoTiff formats. Derived Geo-Referenced Polarimetric and Interferometric data products will also be available for dissemination to the users. A rigorous calibration exercise will be performed by acquiring data over reference targets like Amazon rain-forest & corner reflectors sites for the generation of calibrated data products. Furthermore, various science data products (for science applications) will also be derived from basic data products for operational dissemination.