TerraSAR-X/TanDEM-X

Satellite Description

TerraSAR-X is an X-band SAR satellite mission operated by the German Aerospace Centre (DLR) and Airbus Defence and Space. Launched in 2007 with an initial lifetime of 5 years, TerraSAR-X continues to operate and deliver high quality data. It provides data in multiple acquisition modes which can be used for many applications from disaster monitoring to oceanography. Since 2010, TerraSAR-X has been paired with the TanDEM-X satellite (also operated by DLR). Together they form the first reconfigurable spaceborne SAR interferometer for 3-dimensional terrain mapping. The presence of this identical platform permits the development of a global, high-precision DEM with a 2 m relative accuracy for flat terrain.

Observation Scenario

• Swath width: Depends on acquisition mode (see Sensor Characteristics)

• Orbit: Sun-synchronous

• Inclination: 97.44°

• Altitude: 514 km

• Lifetime: At least 5 years

Sensor Characteristics

Four data acquisition modes:

• • ScanSAR Wide (SCW): Swath width up to 270 km with 6 scans, single polarization (VV, HH, VH, HV).
• • ScanSAR (SC): 100 km x 150 km scene size, single polarization (VV, HH).
• • StripMap (SM): Standard scene size is 30 km x 50 km but length can be extended to 1650 km, single (VV, HH) or dual (HH & VV, HH & HV or VV & VH) polarization.
• • Spotlight (SL): 10 km x 10 km scene size, single (VV, HH) or dual (HH & VV) polarization.
• • High-Resolution Spotlight (HS): 5 – 10 km x 10 km scene size, single (VV, HH) or dual (HH & VV) polarization.
• • 300 MHz High-Resolution Spotlight (HS 300): Scene size depends on incidence angle, single polarization (VV, HH).
• • Staring Spotlight (ST): Scene size depends on incidence angle, single polarization (VV, HH).
• • TanDEM-X DEM: Relative vertical accuracy of 2 m for slope < 20 %, 10 m absolute vertical accuracy.

Spatial Resolution

• SCW: 40 m

• SC: 18 m

• SM: 3 m

• SL: 1.7 – 3.5 m

• HS: 1.4 – 3.5 m

• HS 300: 1.1 – 1.8 m

• ST: 0.24 m azimuth, 1 m range

• DEM: 12 m, 30 m, 90 m

Temporal Resolution

1 – 11 days

Data Products

• Single Look Slant Range Complex (SSC) – amplitude and phase information, intended for interferometry and polarimetry.

• Multi-Look Ground Range Detected (MGD) – reduced speckle, no geocoding applied.

• Geocoded Ellipsoid Corrected (GEC) – resampled and projected to WGS84, no terrain correction.

• Enhanced Ellipsoid Corrected (EEC) – terrain corrected.

• Orthorectified Image (ORI ^SAR) – terrain corrected with high precision DEM.

• Radiometrically Corrected Image (RAN ^SAR) – additional correction on GEC or EEC.

• Mosaic (MC ^SAR) – combinations of ORISAR, EEC or GEC to cover a large area.

• Ascending/Descending Merge (ADM ^SAR) – combination of images from different orbits, can mitigate shadow and layover.

• Oriented Image (OI ^SAR) – subset of a scene.

Archive Availability

• 30 m and 90 m DEM products are downloadable at  EOC Geoservice TanDEM-X

• ESA archive and tasking services are available at  TerraSAR-X/TanDEM-X full archive and tasking – Earth Online

Data Continuity

TanDEM-L is proposed and will consist of 2 L-band radar satellites for measurements of the ocean, land, snow and ice. For further information on the TerraSAR-X and TanDEM-X missions see here.