TerraSAR-X
From INVESaTWIKI
TerraSAR-X
The merger of some of the largest European
aerospace companies resulted in the creation of
EADS and its subsidiary ASTRIUM, responsible
for all EADS satellite related business. Based on
the experiences with SAR technology from various
ESA contracts (ERS, ENVISAT) and the German
national SAR missions (SIR-C, SRTM) and based on
economic feasibility and market studies, ASTRIUM
and its earth observation application and exploitation
units created the concept of an L-Band and X-Band
SAR satellite constellation to serve multiple application
needs of operational users. The financing of
these satellites was supposed to be guaranteed with
contributions from the governmental sector including
ESA.
In March 2002, the German Space Agency, DLR,
and EADS ASTRIUM GmbH signed a PPP agreement,
under which DLR orders from ASTRIUM the
design, built and launch of an innovative X-Band SAR
satellite, called TerraSAR-X. ASTRIUM contributes
significantly to the project and in return receives the
exclusive and global commercial exploitation of 50%
of the capacity of the satellite.
The commercial distribution
is managed thru InfoTerra, Friedrichshafen,Germany, in cooperation with other partners from ASTRIUM,
namely Spot Image. The other half of the
satellite data will be exploited for science use by DLR
thru an international “Announcement of Opportunity”
(AO).
The 1023 kg TerraSAR-X satellite delivers X-Band
SAR data in various modes. The Spot-Light mode will yield the finest resolution data with
about 1m pixel size for a 10 km × 10 km image. The
ScanSAR mode delivers 16m resolution at 100 km
swath. All imaging modes offer a full polarisation capability.
A special “split antenna” mode will allow
experimental in track interferometry, for instance for
mapping moving objects. The satellite will fly in a
514 km dawn–dusk orbit and is scheduled for launch
in mid 2006.
A similar PPP agreement between ASTRIUM and
British authorities to ensure the availability of the
L-Band SAR counterpart (TerraSAR-L) did not materialise.
Instead, further studies on the concept of
TerraSAR-L have been funded thru the ESA Earth-
Watch programme. But it is questionable, whether
these will proceed in the construction of a satellite or
whether it will be amalgated into the ESA SENTINEL
series. [1]
References
[1] G.Schreier, S.Dech
"High resolution Earth observation satellites and services in the next decade - A european perspective".
