Modern warfare has changed from the days when battles were fought on large battlefields. Now more often than not governments and security forces are battling insurgent activities carried out by forces that hide men and materials under the cover of foliage. In several parts of the world it has become increasingly necessary for security forces to acquire the capability to see, remotely from the air, what is hiding under the forest cover. Foliage Penetrating Synthetic Aperture Radars provide precisely this capability.

Since the introduction of Synthetic Aperture Radar (SAR) immediately after World War II, radars employing SAR technology have become faster, smaller, and have gained much higher performance levels with every passing year. With the advent of modern fast computer signal processing, the handling of image data from Synthetic Aperture Radars has become precise and almost photo like. The defining characteristics of SAR systems is the use of relative motion between an antenna mounted on an airborne platform and its target region to create a large synthetic aperture that provides the coherent-signal variations which are used to obtain a fine spatial resolution of the scanned data. The latest SAR systems can provide resolutions of a few centimetres.