Performance assessment of along-track interferometry for detecting ground moving targets

Along-track interferometry (ATI) is an interferometric synthetic aperture radar technique that can be used to measure Earth-surface velocities. As such, the ATI technique holds promise for the detection of slowly moving ground targets. However, the models often used to characterize ATI performance were developed mainly in the context of mapping ocean currents, and they do not necessarily apply to the case of discrete, moving ground targets amidst clutter. We provide expressions for more accurately modeling the behavior of an ATI system in the context of ground moving target indication. Analysis and design equations are given for topics including target defocus, signal-to-noise and signal-to-clutter ratios, interferometric correlation, interferometric phase bias, target detection, geolocation accuracy, and area coverage rate.