4. APPLICATION ASPECTS
The output of this procedure are tie-points being
automatically determined in 2 or more SAR images.
Potential application areas for such points are given for
instance through SAR image coregistration and SAR
block processing tasks, respectively.
In the first case the tie-points can be used to register
multitemporal sets of SAR images (time series)
automatically. In the second case the basic intention is
the treatment of SAR image blocks in analogy to
photogrammetric procedures. Here, the main objective is
to use tie-points being detected in the SAR image block
together with ground control points within a least squares
SAR image block adjustment in order to determine the
SAR mapping models simultaneously for all images of the
block. The background idea is to cover large areas with
low ground control point density on the one hand and, if
necessary, to bridge over areas with no ground control at
all on the other hand.
Typical application areas for SAR block processing could
be third world areas being insufficiently mapped until
today. Based on related examples over well-mapped Mid-
European areas the potential of automatic tie-pointing for
such applications shall be demonstrated.
ACKNOWLEDGEMENT
The work described in this paper has been carried out for
the Deutsche Forschungsanstalt für Luft- und Raumfahrt
(DLR) within the German ERS ground segment under
ESA subcontract (DLR contract No. 6-056-0011). The
support of ESA as well as of DLR is gratefully
acknowledged.
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