The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part Bl. Beijing 2008 
• Radiometric normalisation: resulting in gamma 
naught (y 0 ). 
The output of the radiometric correction (called RaN SAR ) and 
normalization will be scaled to a pixel depth corresponding to 
the product specification. 
The standard map projections are UTM or UPS with WGS84 
ellipsoid. 
Radiometric correction may be preferred if the images are to be 
used for classifications which do not take angular dependencies 
of the SAR data into account. Further, it is also important in 
order to minimize the differences in the radiometry of the 
various images if several images of the same area or 
neighbouring areas are to be composed. 
Fig 8 and Fig 9 illustrate the corrections added by the 
computation of the sigma naught coefficient. 
Fig. 8: Sion (Switzerland) - SL - EEC product 
Fig. 9: Sion (Switzerland) - SL - RAN sar product 
2.1.2 Orthorectified Image - ORI sar 
The ORI processor generates a high precision terrain corrected 
geocoded image product, and can generally be used for all TS-X 
image modes. For the generation of such an adavanced ORI 
product digital elevation models (DEM) provided by or 
purchased for a customer are used. It is assumed that the DEM 
which is used for advanced ORI production provides a higher 
vertical accuracy and a better spatial accuracy in comparison to 
DEMs available from the DEM database, which will be 
provided by DLR. 
The ORI sar product is represented in map geometry. The 
standard map projections are UTM or UPS with WGS84 
ellipsoid. 
The ORI sar is available with the radiometric representation in 
radar brightness p 0 like the Basic Image Products by default; or 
as RaN SA product. 
This product is expected to provide a higher level of geometric 
correction in comparison to Basic Image Products due to higher 
quality DEMs being used and sensor model optimization 
procedures being applied. It can be interpreted very quickly and 
is ideal for combination with other sources of information. 
2.1.3 Mosaic - MC SAR 
To cover a geographical area larger than a standard scene, 
neighbouring geocoded or orthorectified images are seamlessly 
combined into one image. Possible input products are ORI SA , 
EEC or GEC, depending on the customer’s localization accuracy 
requirements. 
The MC SAR is represented in map geometry. The standard map 
projections are UTM or UPS with WGS84 ellipsoid. The product 
provides seamless image information over a large area. It is 
quickly interpretable and combinable with other sources of 
information. Thus, it can be used for map sheet generation. 
2.1.4 Ascending/Descending Merge - ADM sar 
Typical characteristics of SAR images acquired over rugged 
terrain are the radar layover, foreshortening and shadow effects, 
which are not useful in an ortho-rectified product A reduction of 
these effects can be achieved by a combination of ortho-rectified 
SAR images which have been acquired from ascending and 
descending right looking orbits. Respective merging options are 
included in the VA processing suite, resulting in a so-called 
ADM sar product. 
During ascending/descending merge, an ascending and a 
descending ortho image are combined in order to replace no 
information areas - like layover and shadow areas - by 
information available in the respective other image. Furthermore, 
also for the information areas an “optimized” output pixel can be 
generated, based on decision and merge criteria, which consider 
e.g. the local incidence angle or pixel resolution relationship. 
EEC, ORI sar or MC SAR can be used as input to the ADM sar 
generation. The Source Image Mask (SOU) will present the 
origin of each pixel in the product. The ADM sar is represented 
in map geometry. The standard map projections are UTM or 
UPS with WGS84 ellipsoid. 
The ADM sar is of particular interest for areas with steep 
mountain terrain, where shadow and layover can significantly 
disturb the analysis. 
2.1.5 Oriented Image - OI SAR 
The Oriented Image is a subset of an orthorectified or geocoded 
image scene, mosaic or ascending / descending merge. The 
subset region is defined by the customer through an area of 
interest polygon or comer coordinates of the desired region. The 
product can either be characterized by the user defined area of 
interest or by a map sheet orientation according to relevant 
mapping standards or customer defined extensions. The product 
is represented in map geometry, with the standard map 
projections UTM or UPS with WGS84 ellipsoid. 
The OI SAR can be combined with other sources of information, 
so it can directly be used e.g. for map sheet generation. The 
customer receives an image that covers the specified area of 
interest rather than satellite-typical image strips that may only 
cover the area in fractions. 
2.2 Processing options for Value Added Products 
All TS-X Value Added Products are accompanied by auxiliary 
23Q raster products, which can contain conversion, positional