NOS.
RADARGRAMMETRIC EXPERIMENTS WITH SPACE SHUTTLE SIR-B
IMAGERY
F. Leber! U, G. Domik P, J. Raggam 2). J. Cimino 9, M. Kobrick ©
1) VEXCEL Corporation, Boulder, CO 80301
2) Graz Research Center, A-8010 Graz, Austria
3) Jet Propulsion Laboratory, Pasadena, CA 91109
ABSTRACT
SIR-B resulted in the most comprehensive radar image data set for radargrammetric work that is
currently available. The paper reviews the results obtained with stereo image pairs and with the
creation of secondary radar image products.
1. INTRODUCTION
One of the parameters of great speculation in past radar mapping studies did address the radar look
angle and look angle disparities in overlapping stereo images. SIR-B provided a series of radar
coverages of radargrammetric interest and with variations of the look angle. In particular data sets
were generated as follows:
(a) 3 overlapping strips over Mt. Shasta, California;
(b) 4 overlapping strips over Gordon la Graza, Argentina;
(c) 5 overlapping strips over José de San Martin, Argentina;
(d) 3 overlapping strips over Sydney, Australia;
(e) 2 overlapping strips over Illinois.
Analysis of the data began soon after the SIR-B flight in October 1984, first working with the data set
(a) of Mt. Shasta. The results have been reported in earlier papers (Leberl et al., 1986a) and Leberl
et al. (1986b): the analysis addressed the creation and use of a digital terrain elevation model from
the overlapping images.
Of two elaborate data sets from Argentina only one has thus far been analyzed; results for the Gordón
la Graza area were reported in papers by Cimino et al. (1986), Domik et al. (1986) and Leberl et al.
(1986c).
Finally, very recent and as yet unpublished work provided insights into so-called opposite-side stereo
geometry with the help of the Illinois data (e). Data sets (c) and (d) are still awaiting an analysis.
Additional radargrammetric work was performed by Ramapryan et al. (1984) emphasizing
processing technology. The contributions and experiments of Zebker and Goldstein (1985) to
extract topographic relief information through interferometry are not counted into radargrammetric
SIR-B work since they employ SAR data in non-image form.
The paper summarizes the parameters for the imaging geometries of the data sets, it describes the
current status of SIR-B radargrammetry and presents a discussion of the capabilities and limitations of
the data. It will be shown that topographic height measurements can be made with root mean square
errors of + 10 to 20 m with the data from Illinois, and that precision registration and "geo-coding" is
feasible using stereoradargrammetry.
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