Optimal target detection using one channel SAR complex imagery: application to ship detection

Target detection is a delicate process in SAR imagery. Single-point targets are often supposed to have a reflectivity level higher than the clutter mean power and one could think that a simple thresholding operation would permit their detection. Because of the speckle, however, the signal has a very high variability (especially in the one-look case) which may cause confusion between high speckle peaks and target points. The authors present optimal target detection based on radiometric criteria. Complex images permit optimal radiometric estimation by means of the spatial whitening filter, which takes spatial correlation into account. The application to ship detection on a complex fine mode Radarsat image is presented.