Maintenance of radiometric calibration performance of RADARSAT-1

RADARSAT-1, the first Canadian SAR remote sensing satellite, was launched on November 4, 1995. After commissioning, it was put into routine operations on April 1, 1996. Significant effort has been expended in the provision of geometrically and radiometrically calibrated products to users. After calibration, the beams are monitored routinely as part of the Maintenance Phase for image quality. Radiometric accuracy performance is monitored through periodic measurements of the elevation beam pattern of single beams using images of the Amazon rainforest. For some beams, pattern changes have occurred after calibration, but compensation has been made in the processor by recalibrating these beams. This paper describes the overall process of data acquisition, data analysis and recalibration for maintaining calibration accuracy within the design goal limits [1].