Miller, David (EADS Astrium GmbH, 88039 Friedrichshafen, Germany)
The TanDEM-X (TerraSAR-X Add-on for Digital Elevation Measurement) satellite is heavily based on the TerraSAR- X satellite which was successfully launched in mid-2007. TanDEM-X will have an additional Cold Gas Propulsion System and an Inter-Satellite Link Receiver and is planned for launch in late 2009. The CGS will allow fine adjustments of the TanDEM-X orbit in very close proximity to TerraSAR-X to give a variable interferometric baseline for syncronised bistatic SAR measurements for the determination of a Digital Elevation Model of the Earth’s land surface. SAR phase syncronisation is achieved using 2-way transfer of USO-based X-band pulses. The TanDEM-X ISL-R will allow reception of S-band telemetry data from TerraSAR- X to support collision avoidance and TanDEM-X Autonomous Formation Flying. This paper describes the development approach and design/performance aspects for bistatic operation.