You are here: Home:Departments:Satellite SAR-Systems

Department Satellite SAR Systems (Dr. Manfred Zink)

Main objective of the Satellite SAR Systems department is the research on space borne SAR systems and the development and operation of SAR-missions.

These SAR-systems deliver data in single or multiple frequency bands with polarimetric and interferometric information which are used to process high resolution radar images, Digital Elevation Models, for the derivation of geo-physical parameters and for moving target parameters (GMTI).

The department has SAR and space expertise gained from the experience with three Space Shuttle missions (SIR-C/X-SAR und SRTM), with the ENVISAT Mission of ESA, with the TerraSAR-X and TanDEM-X project and from the work on several space borne SAR system studies.

The team is competent in SAR system engineering, overall SAR system performance analysis, in SAR processing and calibration, in algorithm development, mission planning and SAR instrument operations.

Research and Project Groups

TanDEM-X (Dipl.-Ing. Daniel Schulze)

In the TanDEM-X project group, the management of the sub-project System Engineering and Calibration and the Institute’s contribution to TerraSAR-X/TanDEM-X Ground Segment development are concentrated. Besides the expertise in development and operation of SAR-systems the group has an in-depth experience in mission analysis including the simulation of satellite orbits, analysis of data flow and strategies for data acquisition. The group is responsible for the development of the extended Instrument Operations and Calibration Segment (IOCS) for TerraSAR-X and TanDEM-X. This extension covers software systems for: the operational planning of the complete TanDEM-X acquisitions, the generation of radar parameters and commands as part of the Mission Planning System, the generation of the required „Auxiliary Data“ for the SAR-processing as well as tools for verification and calibration. As support for the Mission- and Ground Segment development extended simulation environments for critical sub-systems e.g. the mission planning system and the ground station network, the synchronisation system or the mosaicking and calibration of Digital Elevation Models are being established and maintained.

Mission Engineering (Markus Bachmann)

The research group Mission Engineering is mainly engaged with aspects relevant for the realization of satellite SAR missions with respect to the mission in general. This means in particular the establishment of acquisition scenarios, the analysis of SAR relevant questions and the overall monitoring of the most relevant system parameters. During the planning phase before a SAR mission, acquisition concepts need to be developed. For this purpose, all relevant parameters like acquisition modes and their data rates, the capacity of downlinks and the areas that shall be acquired are connected to a coherent concept. Orbit analyses are incorporated in these concepts, from which orbit parameters and orbit scenarios are derived. During the mission, the acquisition scenarios have to be adapted to actual needs to successfully accomplish the mission. As another field of work, long-term analyses of the SAR system are performed to ensure the goals of the overall mission. Regular reports about the actual state of relevant system parameters provide information about the behavior of the satellite and of the whole system. In the actual mission TanDEM-X for example, the main focus lies on the dedicated planning of the global acquisitions for the digital elevation model. Directly connected to this planning is the optimization of the helix formation both satellites are flying in. To monitor the quality of the acquisitions, global maps are derived and dedicated analyses concerning the relevant interferometric parameters are performed. These are again input for the future planning.

TerraSAR-X/TanDEM-X Mission Manager (Dr. Stefan Buckreuß)

The Mission Manager’s responsibility is the provision of data products in equal shares to both the scientific and commercial customers in order to ensure the achievement of the TerraSAR-X/TanDEM-X mission objectives. He coordinates the utilization of the TerraSAR-X/TanDEM-X mission according to the terms of the public private partnership agreement. The tasks cover the monitoring and coordination of the complete satellite activities including the operation of the SAR instruments and the interfaces to the secondary payloads. In case of anomalies or contingencies the Mission Manager has to approve actions that go beyond the nominal satellite operation. In his role as head of the TerraSAR-X/TanDEM-X Mission Board he has the authority to solve conflicts. He also has to track the implementation of Mission Board decisions in the Ground Segment and to monitor the integration and configuration of the Ground Segment especially with respect to necessary extensions for TanDEM-X. The Mission Manager reports regularly to the “Gemeinsamer Ausschuss” and to the head of the TerraSAR-X/TanDEM-X project.

System Performance (Benjamin Bräutigam)

The research group “System Performance” covers essential system aspects of state-of-the-art satellite development as well as analysis of spaceborne SAR quality parameters. In the frame of public-private partnership of the TerraSAR-X and TanDEM-X missions the group gains a high expertise in design, assembly, and acceptance tests of satellite systems. The instrument hardware and software knowledge is expanded by regular radar instrument operations of running and future SAR satellites. Innovative SAR system concepts require theoretical computation and optimization of the SAR performance from its mission and instrument parameters. The input for analysis can be antenna characteristics, noise figure, orbit parameters or pulse repetition frequency (PRF). The SAR performance is optimized for the desired image quality derived from the system requirements. After satellite launch the processed SAR images are characterized for resolution, scene size, and signal quality. The research group is responsible for the SAR performance of specified products as well as experimental modes of TerraSAR-X and TanDEM-X.

Calibration (Dr. Marco Schwerdt)

Main objective of the calibration group is the development of concepts and methods for calibration and verification of imaging radar systems and their products. In addition to the development of algorithms and software tools also reference targets like transponders or corner reflectors are specified and developed as prototypes. The Oberpfaffenhofen Calibration Facility allows the execution of calibration campaigns over large test sites. Extended calibration campaigns for the ERS-1/2 (1991-1996), SIR-C/XSAR (1994), SRTM (2000), and ENVISAT/ASAR (2002) missions have been planned in detail and successfully performed. The expertise gained from these missions has been converted into novel concepts and methods for precise calibration of active phased array SAR-systems and successfully demonstrated for the first time in orbit with TerraSAR-X. With the excellent results of the TerraSAR-X mission a bench mark for calibration of future SAR-systems (TanDEM-X, Sentinel-1) has been set.

Contact

Dr.-Ing. Manfred Zink
Head of Department Satellite SAR Systems
Microwaves and Radar Institute, Satellite SAR Systems
Oberpfaffenhofen-Wessling
Tel.: +49 8153 28-2356
Fax: +49 8153 28-1449

Dipl.-Ing. Daniel Schulze
Head of the TanDEM-X Group
German Aerospace Center
Microwaves and Radar Institute, Satellite SAR Systems
Oberpfaffenhofen-Wessling
Tel.: +49 8153 28-3383
Fax: +49 8153 28-1449

Dipl.-Ing. Markus Bachmann
Head of the Mission Engineering Group
Microwaves and Radar Institute, Satellite SAR Systems
Oberpfaffenhofen-Wessling
Tel.: +49 8153 28-2395
Fax: +49 8153 28-1449

Dr.-Ing. Stefan Buckreuss
German Aerospace Center
TerraSAR-X/TanDEM-X Mission Manager
Oberpfaffenhofen-Wessling
Tel.: +49 8153 28-2344
Fax: +49 8153 28-1149

Dipl.-Ing. Benjamin Bräutigam
Head of the System Performance Group
Microwaves and Radar Institute, Satellite SAR Systems
Oberpfaffenhofen-Wessling
Tel.: +49 8153 28-3121
Fax: +49 8153 28-1449

Dr.-Ing. Marco Schwerdt
Head of the Calibration Group
German Aerospace Center
Microwaves and Radar Institute, Satellite SAR Systems
Oberpfaffenhofen-Wessling
Tel.: +49 8153 28-3533
Fax: +49 8153 28-1449


Compute TerraSAR-X or TanDEM-X reference target alignment angles