ASAR - Envisat's Advanced Synthetic Aperture Radar - Building on ERS achievements towards future earth watch missions

Following on from the highly successful ERS-1/2 SARs, which have contribute d to major scientific achievements and initiated preoperational and commerc ial applications of SAR data, ESA is now ready to launch Europe's largest r emote-sensing satellite to date, carrying an Advanced Synthetic Aperture Ra dar (ASAR). The ASAR is an all-weather, day-and-night high-resolution radar-imaging ins trument. Compared with the ERS SAR, it features extended observational capa bilities, three new modes of operation and improved performances. The ASAR system has been designed to provide continuity with ERS SAR, but also to ex tend the range of measurements through the exploitation of its various oper ating modes and the development of new algorithms and data products. The En visat ground segment will allow the generation of near-veal-time and off-li ne precision images to satisfy the needs of the scientific, institutional a nd commercial data users.