An approach to ship motion estimation with dual-receive antenna SAR

A SAR system with an antenna divided into sub-apertures is considered for marine surveillance. Ship position and radial and along-track components of its cruising velocity are estimated in the presence of wave-induced motion, using a combination of adaptive beamforming, frequency tracking and along-track interferometry. The effectiveness of this new approach is illustrated by an airborne SAR example. The extension to spaceborne SAR is discussed.