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The utility of ASAR data will be greately enhanced if the Radiometric and Geometric quality of the data satisfies the requirements of applications. 7 secenes of ASAR data acquired during April 2004 - June 2005 have been processed to assess the Geo-location accuracy and also temporal / spatial variability of backscattered signatures. Ground Crontrol Points (GPS) approach was used for Geometric accuracy assessment. 80 GCPs spread all through the image were measured using Trimble 5700. It is estimated that the geometric accuracy of the data is within 55 m. This is in agreement with the reported accuracies in the literature. About 20 well defined targets were considered for the backscattering signature study. The size of each target varies from 1000 to 5000 SLC pixels for good statistical stability of the signature. It has been estimated that the Standard Deviation (STD) of the sitgnature is 1.3% and the temporal / spatial variability of the signatures (considering all varieties of targets such as built-up area, grass lands, airports, agricultureal plots, desert soils, etc) are within its STD. During this study period the soil moisture varied from 10% to 6% as recorded from AMSR-E on board Acqua satellite. The ASAR data has been filtered for speckle noise.