Geometric Segmentation of Sea Clutter in Coherent Radar Images: Range–Doppler Map Versus Range–Time–Intensity Map

Abstract

This article aims at providing an efficient algorithm for sea clutter segmentation in coherent radar images. Using multiphase interface motion models, we show that segmentation in the range-time-intensity map gives much more relevant results than segmentation in the range-Doppler Map and avoids the use of assumptions on the clutter frequency response. Several mathematical models are evaluated on real data corresponding to Douglas sea states of approximately 5. Dealing with diffuse interface motion models involving more than two phases allows us to take into account the low contrast, the interference noise, and the contour weakness that are typical of range-time-intensity map images. Sea clutter segmentation allows us, for instance, to obtain oceanographic parameters such as sea state, direction, and velocity of the swell and the wind. It can also be seen as preprocessing that may be useful for target detection.