Fig.6
zimuth
70.65°.
9.14°
2.68%
age. b)
5. TERRAIN'S INHOMOGEINITY TEST
Two additional tests are realised, Fig.7, Fig.8, and they
illustrate and confirm spatial inhomogenity of the terrain
Fig.2a, selected for example in this work.
AREA % VISIBLE BY SAR, H=4080 m
1 ula A fi A A A A
1
1 1
4 ^
0.95 4 F
4
$ 094 ; ;
Bí 1 L
0.85 4 F
| [
1
08 —— —À meme eee t
0 $0 100 150 200 250 300 350
AZIMUTH DEGREES
Figure 7. The percentage of the area that could be seen by the SAR, from different azimuths of the SAR at altitude 4000 m, radius
50 km. For the terrain Fig.2a. Minimum is achieved between 110 and 140 degrees.
AREA % VISIBLE BY SAR
y = -3.113+0.01*x+0.0001*x"2-4.615e-8*x"3+1 174e-11*x"4-1 055e-15*x"5+eps
100 - ' T
10 F "
=, - ;
Qu 4
4
LE 2
;
0 1000 2000 3000 4000
ALTITUDE_M
Figure 8. The percentage of the area that could be seen by SAR, on different altitudes, from point located on 0° azimuth, on the
top of the terrain on Fig.2a. Points - obtained by the visibility analysis, thin line - the polinomial model.
6. CONCLUSION airborne SAR route with minimum loss by shadows. The
supervised classification of the relief *s aspect and slope
Starting on general facts of the previous research on derived on DEM, enables finding the volume for SAR's
mountainous terrain influence on imaging by SAR, an routes, within which foreslopes and backslopes of terrain
approach was developed for the determination of the can be imaged.
International Archives of Photogrammetry and Remote Sensing. Vol. XXXII, Part 7, Budapest, 1998 515