The ERS-1 SAR Performance: A Final Update

The performance of the ERS-1 Synthetic Aperture Radar (SAR) was routinely assessed as the ESA Product and Archiving Facilities (PAFs) via a variety of quality assessment and calibration measures. This paper gives the final ERS-1 SAR quality assessment and radiometric calibration results including internal calibration, ADC power loss implications, stability, noise equivalent radar cross-section measurements and calibration of products processed with nominal replica pulses. Also given are expressions to calculate the radar cross-section of both distributed and point targets as well as ERS-1 attitude and SAR Doppler behaviour derived from SAR imagery.