The Ers-2 Sar Performance: Another Further Update

The performance of the ERS-2 Synthetic Aperture Radar (SAR) is routinely assessed at the ESA Product and Archiving Facilities (PAFs) via a variety of quality assessment and calibration measures. This paper gives the latest ERS-2 SAR quality assessment and calibration results including updates to ERS-2 SAR internal calibration and stability, updates to the ERS-2 nominal replica pulse correction table, noise equivalent radar cross-section measurements and image localisation results. Equations are given for the calculation of distributed and point targets from PRI and SLC products. Also given are ERS-2 attitude and SAR Doppler variations following the change from three to one gyroscope operations in February 2000 and the change to gyro-less operations in February 2001.