[APRS & SIS. Vol.34, Part 7, “Resource and Environmental Monitoring”. Hyderabad. India. 2002 
  
y" 
Figure 3a: Coherenc Image of tandem 
couple of Irak test site. 
5. CONCLUSION 
In the Mauritania test site, it is observed that from the sharp 
differences in coherence values in seawater and coastal area, 
coastline can be mapped from the coherence image of tandem 
or 35-day couple. Coastline evolution study can therefore be 
made either from tandem or 35-day couple. The tandem couple 
is found useful for studying various landcover types and 
geomorphology of the study area. However. beach area from 
the rest part of the coast and urban constellations from the 
surrounding arid-semiarid open fields can be demarcated in 35- 
day couple. which gets confused in the tandem couple with 
moderately high overall coherence in the surrounding areas. 
Merging ascending mode tandem couple with descending mode 
35-day couple coherence images. geomorphological features 
become easier to be mapped. Merging of ascending and 
descending mode tandem couples will therefore be very useful 
for geomorphological mapping of a terrain. Although coherence 
images of temporal baselines in years are not in general useful 
for terrain analysis, under exceptional terrain condition, where 
terrain elements are temporally stable for years. coherence 
images of couples having temporal baselines even in years may 
suitably be utilized for geological. geomorphological or 
landcover studies. This is observed in the coherence image 
€ 
from the test site of Iran. 
  
  
  
Figure 3b: Coherenc Image of 1121-day Figure 4: Coherenc Image of 1121-das 
Couple of Irak Test Site. 
Couple of Iran Test Site. 
References 
Stussi. N.. Kwoh, L.K.. Liew. S.C.. Singh. K.. Lim. H. 
1996. ERS-1/2 Interferometry: Some Results on lropical 
Forest. ESA Workshop on Applications of ERS SAR 
Interferometry. 30 September to 2 October 1996. Zurich 
Zebker, H.A. and Villasenor. J.. 1992. Decorrelation in 
Interferometric Radar Echoes. IEEE Transactions on 
Geosciences and Remote Sensing. 30(3). 950-959. 
Acknowledgements 
The first author acknowledges Prof. V.K. Jha. Head 
Geosciences Division. Indian Institute of Remote Sensing for 
his help and suggestions during the preparation of the 
manuscript. 
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