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

of the lriost impoltant applications in the geological lemote sensing. SAR
images generally pt'ovicle excellent lineament cletails comparecl rvith other.
sensol' clata, as clemoustl'atecl by many investigations using the Seasat SAR
data and Landsat irnagery (Halris [40]). However., thele exist cer.tain SAR
system biases, and thus cautions must be taken rvhen a set of SAR clata is
intelpreted fol geological applications, Importaut rada,- par.ameter.s for irnaging
of surface geological lineaments ar.e: 1) radar. look clilection, 2) inciclence
angle, alcl 3) spatial resolution (HaLris [40]).
Local inciclence angle detelmines the iltensity of the taclar r.etur.n: srnall
incidence ângle leads to intense backscatterirrg (MacDonald [68]). As the
inciclence angle incleases, the ar¡ount of backscattering enel'gy clecleases.
The raclar' look clilection is definecl by the radar squint algle given il
Figule 1.1. In the CCRS's ailborne C-SAR and tlie ÐRS-1 SAR case, the
raclar look clirection is normal to the azimuth. The raclal look directiou is the
rnost inpoltaut factol in imaging lineaments (HaLris [a0]). The raclar. look
clilection biasing (ol the ladar azinluth biasing) ploblem has been atldressecl
by Lownran et al. 1661, ancl Masuoka et aL l75l. The r.aclar look clilection detemrines
the prefelential elhancernelt of the terrain: linear.features rvithin
20' of being parallel to the look clirection ale practically invisil¡le (Lowrnan
et al. [66]), whereas those within 20o of normal to the look clilection ale
strongly highliglited (HaLLis [40]). For this Leason, Lolman ef ø1. [66] suggested
that at least trvo look dir.ections be nandator.y in any SAR application
ploject for geologic in'estigation.
This chapter is focused on two questions:
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