SIR-C/X-SAR: a multifaceted radar

The multifaceted Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) was successfully flown twice in 1994 aboard the Shuttle Endeavour as part of an international imaging radar mission. The United States SIR-C operated at L- and C-band, each with quad polarization, utilizing an active phased array antenna. The German/Italian X-SAR operated at X-band with a single polarization, utilizing an antenna which was mechanically steered in elevation. SIR-C and X-SAR operated synchronously to collect data over common sites. Data were collected for repeat-track interferometric processing at all three frequencies. A total of 143 hours (93 terabits) of SAR data were digitally recorded on tape over the two flights for subsequent processing in the U.S., Germany and Italy. This versatile multifrequency, multipolarization radar system has produced a rich radar data set for Earth scientific investigation and demonstration of spaceborne radar remote sensing capabilities.