X-SAR RADIOMETRIC CALIBRATION AND DATA QUALITY

In April and October, 1994 the X-SAR was flown as part of the SIR-C/X- SAR space radar laboratory missions (SRL-1/2) on the Space Shuttle. Am ongst other activities DLR is responsible for the calibration of all X -SAR data products and is running the German Processing and Archiving Facility (D-PAF). Calibration activities included three major parts. B efore the first mission, we performed a detailed analysis of the overa ll system to localize the main error sources and developed algorithms and procedures to correct these errors, During the missions we concent rated our efforts on calibration campaigns at the Oberpfaffenhofen sup er test site. Post mission activities included the determination of th e antenna pattern and the absolute calibration factor as well as detai led performance analyses. This paper describes the overall approach to radiometrically calibrate the X-SAR and provides information on syste m performance and data quality to users in the different application f ields.