Verifying the Geometric Accuracy of Sentinel-1A and Sentinel-1B Using L0- Products

摘要

The geometric accuracy of Sentinel-1 is usally derived from level-1 products in Stripmap mode using accurate surveyed corner reflector positions. While the range offset is found to be low (~30 cm) an azimuth offset of about 2 m remains. The study investigates the reason for the geometric offsets by deriving the geometric parameters from L0-data. Therefore the pulse round-trip time is analyzed from transmission to reception of a point target's backscatter including a simple pulse compression in range and azimuth. Finally, the azimuth offset is reduced to about 15 cm which indicates an artificial bias arising from SAR processing.