In summary, the digital SLAR data of an agricultural 
area has been evaluated for various types of fielis. The 
overall characteristics of each type of field on a SLAR 
image can be understood by considering its local statistics, 
The present study was conducted for a given enviornment, 
and several observations were apparent during the study 
phase. Among the more immediately apparent were 
discrepancies of gray values within same categories at a 
given angle of incidence. Such variations can be expected 
due to different conditions of same type of landuse 
categories. This leads to the fact that in digital 
classification techniques, the tolerance limit should be 
predefined for each landuse category. The general mean 
characteristics of SLAR return signal from land surfaces 
could also be applied for radiometric calibration of 
various SLAR systems and different images. 
ACKNOWLEDGEMENT 
In thi 
‘This work is a part of the Shug conducted at DPVLR, Xy edo 
West Germany for the Joint ISRO-DFVIR SLAR campaign 1980. This a 
One of the author (SM) is thankful to Department of Space 
(India) for arranging the deputation at DFVLR, West 
Germany for this work. Constant encouragement and useful 
discussions with Dr. W. Keydel, DFVLR, West Germany and taken 
Mr.D.S.Kamat, Space Applications Centre, Ahmedabad, India, MDA di 
are highly acknowledged. The av 
for bo 
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