Comparison of ultrawideband SAR target detection algorithms

A new technique, developed at Lincoln Laboratory, utilizes algorithms developed for two-pass change detection to exploit the differences in aspect angle dependency between target scatterers and clutter scatterers. This technique, referred to as split- aperture detection, involves forming several aspect-angle-diverse SAR images from a single flight pass over a given area by separating the synthetic aperture into sub-apertures during image formation. Change detection algorithms are then applied to these aspect-angle-diverse looks, in the hopes that clutter returns will be nearly isotropic over small variations of aspect angle and will look similar in each image, while man-made objects will provide anisotropic returns over the same angular variation and, therefore, will appear brighter in one image. In this case, the change detection algorithms will significantly suppress the background clutter (thereby significantly reducing the number of false alarms) while enhancing target detectability.