INVERSION OF SYNTHETIC APERTUR,E R,ADAR (SAR) - MSpace ...

thlough the Radon tlansfolm is shorvn in Figure 6.14. The coordinates of trvo
blight spots indicate exactly the distance between the trvo hvperbolas of the
original irnage (Figule 6.12) and the refelence ternplate (Figur.e 6.13). Each
of trvo blight spots is locatecl at the clossing point of two clirn str.aight lines
which are il fact asymptotes to the hypelbola. Iu surnrnar.y, coor.clinates of
the apexes can be detelmined by locating the bright points (or.dark point if
oliginal value is lorv DN-value) at the cr.ossing point of trvo cliln asymptotes.
Corlelation using the Raclol transfolrn apploach rvas applied to the airl¡ome
C-bancl SAR data from the Wekusko Lake area, Manitoba Canacl¿
(Figule 6,15). The topoglaphy of this area is characterized by the vely lorv
relief typical of the Canaclian shield, which results in an SAR irnage rvith
vely lou' laclar shacloiv. Several folcl structures are visible, however., due to
changes in terlain slope especially in the bottom half of the irnage (Figule
6.15). Palts of lake sholelines which are palallel or subpalallel to azimuth
ale explessed by high blightness, wheLeas rnany fold structules ar.e expressed
by dalker tone. In Figure 6,15, the squares annotated by "4", "B", aucl ,,C"
inclucle apexes of visil¡le fold stluctures. To locate apexes of fold stluctures,
a lefeleuce hypelbola is selected which is repr.esentecl by a equation
y : 4'5@+ QÐ" -
145 (Figure 6.16). The selection of the leference hypelbola
is based on the shape analysis of the fold rvhose apex is located at
Colrelation using tlìe Foul'iel transform rvas tested first, rvith the lesult
shown in Figure 6.17. The colrelation thr.ough FFT rvas calr.iecl out after.
zeÌos weÌe paddecl to tìre original data in both z- ancl y-dirnension. No
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