A potential German contribution to the LightSAR program

LightSAR is a NASA initiative to develop a low-cost Earth-imaging radar satellite system that will return valuable science data, demonstrate advanced technologies, and inaugurate commercial radar imaging from space. The present LightSAR system design considers a two frequency SAR instrument operating in a fully polarimetric mode at L-band and in a dual polarimetric mode at X-band. The X-band sensor is an active phased array antenna consisting of several electrical panels and can operate in one of the following modes: spotlight mode with /spl plusmn/0.75/spl deg/ azimuth scan, ScanSAR mode with /spl plusmn/12.5/spl deg/ elevation scan, strip map mode with 20/spl deg/ to 55/spl deg/ incidence angle access range. A flight representative breadboard of such an electrical panel is currently developed within the DESA project funded by the German Space Agency (DLR). The dual polarised X-band SAR instrument requires 3341 W DC power and indicates a mass of 415 kg. Optionally, a single polarisation instrument can be designed which requires only 2080 W DC power and a mass of 385 kg.