The External Calibration of TerraSAR-X, a Multiple Mode SAR-System

TerraSAR-X is a versatile X-Band SAR satellite operating in Stripmap, Spotlight and ScanSAR modes with selectable or dual polarisation. Additionally, experimental modes are possible, like wide bandwidth operation providing even higher resolution, or a left-looking mode. Consequently, cost and time effective concepts for external calibration are mandatory because of the large number of modes and possible antenna patterns. External calibration meets the challenge of calibrating in a short time frame during commissioning. The paper describes the developed strategy planned for the TerraSAR-X commissioning phase and discusses its implementation. External calibration is presented as a part of the IOCS Calibration Section in the TerraSAR-X Ground Segment.