TERRASAR-X AND TANDEM-X:
REVOLUTION IN SPACEBORNE RADAR
Ralf Dueling
Infoterra GmbH
Claude-Domier-Strasse, 88090 Immenstaad, Germany
E-mail: ralf.duering@infotera-global.com
www. info terra-global .com
Commission VI, WG VIM
KEY WORDS: TanDEM-X, spacebome radar satellite, X-band, high-resolution imagery, single pass SAR interferometry, digital
elevation model
ABSTRACT
Commercially available imagery is and will remain indispensable to civilian and military organizations gathering various types of
geo-spatial information. Whether fulfilling international agreements, providing military contingents in international peacekeeping or
humanitarian missions, or conducting joint technical exercises with other countries - a reliable access to timely, high resolution
remote sensing data is an essential basis for well-informed decision making, particularly in time-critical situations. Today,
organizations with those needs customarily resort to high resolution data acquired by optical sensors - often a lengthy operation. The
radar satellite TerraSAR-X, and at a later stage together with TanDEM-X with it’s complementary near-real time data acquisition
capabilities, offer a whole new approach to the use of space-borne datasets for mapping purposes in timecritical situations.
1. INTRODUCTION
Due for launch in June 2007, EADS Astrium’s new radar
satellite TerraS AR-X will provide Earth observation data of
unprecedented quality, with a resolution of up to one metre,
for increasingly diversified commercial as well as for scientific
applications. Its scheduled lifetime will be 5 years. However,
the whole SAR programme will last more than 10 years.
Commercial users require detailed data adapted to their
individual requirements, available quickly and reliably,
independent of daylight and weather conditions. The design
and performance of TerraS AR-X will exactly meet these
requirements. The Synthetic Aperture Radar (SAR)
instruments of the spacecraft supply extremely detailed radar
images, day and night, under all weather conditions. The
acquired data is the basis for a wide variety of products and
services, such as highly sophisticated client-specific image
interpretation, topographic maps up to a scale of 1:10,000,
geo-spatial databases and terrain analysis much in demand for
a wide scope of applications. Other application sectors include
environmental planning, land cover and natural resource
exploration, regional and urban development, catastrophe
response and relief, insurance and risk assessment as well as
applications in border control, security and defence.
New-quality data records, as provided by TerraS AR-X,
will also offer a vast number of new research incentives,
for instance in forestry, ecology, geology, hydrology and
oceanography. The smallest movements of the Earth's
surface due to plate tectonics, volcanism, earthquakes,
and land slides are further challenging fields of
application of TerraS AR-X interferometry.
The space mission TerraSAR-X is the first German space
project implemented under a Public Private Partnership (PPP).
Cooperation partners are the German Aerospace Centre (DLR)
and EADS Astrium. Under this construct DLR will be
responsible for the scientific use of the TerraSAR-X data,
whereas commercial marketing will be undertaken
exclusively by Infoterra GmbH, a wholly-owned EADS
Astrium subsidiary specialising in the collection, processing,
and distribution of air- and spacebome imagery and value-
added products.
2. DEMAND FOR HIGH RESOLUTION DATA
Commercially available imagery is and will remain
indispensable to organizations gathering intelligence
information. Whether fulfilling international agreements,
providing contingents in international peacekeeping or
humanitarian missions, or conducting joint exercises with
other countries - a reliable access to timely, high resolution
remote sensing data is an essential basis for well-informed
decision making, particularly in time-critical situations.
Today, organizations with those needs customarily resort to
high resolution data acquired by optical sensors with which
huge area coverage can only be accomplished with large
temporal offsets. TerraSAR-X, with it’s complementary near-
real time data acquisition capabilities, offers a whole new
