The NASA-ISRO SAR mission - An international space partnership for science and societal benefit

摘要

The National Aeronautics and Space Administration (NASA) in the United States and the Indian Space Research Organisation (ISRO) have embarked on the formulation of a proposed Earth-orbiting science and applications mission that would exploit synthetic aperture radar to map Earth's surface every 12 days. The mission's primary objectives would be to study Earth land and ice deformation, and ecosystems, in areas of common interest to the US and Indian science communities. To meet demanding coverage, sampling, and accuracy requirements, the system would require a swath of over 240 km at fine resolution, using full polarimetry where needed. To address the broad range of disciplines and scientific study areas of the mission, a dual-frequency system was conceived, at L-band (24 cm wavelength) and S-band (10 cm wavelength). To achieve these observational characteristics, a reflector-feed system is considered, whereby the feed aperture elements are individually sampled to allow a scan-on-receive (“SweepSAR”) capability at both L-band and S-band. In the partnership, NASA would provide the instrument structure for both L- and S-band electronics, the L-band electronics, the reflector and associated boom, and an avionics payload to interface with the radar that would include a solid state recorder, high-rate Ka-band telecommunication link, and a GPS receiver. ISRO would provide the spacecraft and launch vehicle, and the S-band radar electronics.