The TerraSAR-X Payload Ground Segment: Pre-Launch Status and Performance

Abstract

TerraSAR-X, the first national German radar satellite, is scheduled for launch in 2006. It carries an X-band high resolution synthetic aperture radar instrument featuring imaging modes like StripMap, ScanSAR and, particularly, SpotLight in a variety of different polarization modes. Thus the TerraSAR-X mission will provide both the scientific and commercial user community with a variety of products from advanced SAR modes. The TerraSAR-X space segment was built by EADS Astrium GmbH, the ground segment by DLR. One central ground element is the payload ground segment (PGS) which is responsible for the reception of the SAR payload data, their archiving and processing and the distribution of the generated SAR basic products to users. It is currently in its final pre-launch integration and test phase. To test the operational SAR data processing chain under most realistic TerraSAR-X conditions, specific SAR proving grounds have been set up. These are supplemented by a number of test data generation tools and - most important - by a considerable amount of test data generated using the satellite SAR instrument itself and made available for ground segment testing. Thus, an extensive PGS SAR test bed is currently in place and used for both functional and performance end-to-end tests. This paper depicts the various PGS elements for SAR data reception, transcription and processing and summarizes their functionality and design in terms of hard- and software. Both the PGS SAR test bed and the performed end-to-end tests are described. Selected test results which characterize the PGS pre-launch performance are reported.