Abstract : For earth observation, microwave remote sensing has been a useful technology that provides sensing capability of earth terrain with wide coverage. Images from satellite based Synthetic Aperture Radar (SAR) are acquired to provide ground information about various types of earth terrain sensed (such as vegetation, farm, urban area, sea ice and snow covered land, etc). In order to interpret these SAR images correctly, it is necessary to understand how microwave interacts with these earth media.