ABSTRACT
The active remote sensing refers to a process where in the instruments with a capability to illuminate object/target and to collect the reflected or backscattered radiation therefrom are used for deriving information on the objects/targets. Active microwave sensors could be grouped into imaging sensors and non-imaging sensors. Synthetic aperture radar (SAR) uses a relatively small antenna that sends out a relatively broad beam perpendicular to the sensor platform. Some of the commonly used modes of SAR system include strip map mode, spotlight mode and scan mode. The spatial resolution of a radar image is defined in two directions: parallel and perpendicular to flight line/satellite ground track. The Copernicus Space Component comprises a series of spaceborne dedicated missions called "Sentinels" and is developed and procured by the European Space Agency. The Sentinel comprises six satellites: Sentinel-1, Sentinel-2, Sentinel-3, Sentinel-4, Sentinel-5, and Sentinel-5P.
