Research on the spaceborne SAR image processing and feature extraction for ocean fronts detection

This paper discusses the interaction of short surface waves with shearing and converging current. On the basis of the spectral perturbations caused by the interaction, the influences of the interaction on the ocean surface wave spectral density and gradients are analyzed. A two-scale electromagnetic scattering model explains not only the interaction between short-wave and radar backscatter, but also the interaction between long-wave and radar backscattering. Then SAR imaging mechanism of ocean fronts is derived. In SAR images, the scale of ocean fronts is 2-3 orders larger than that of sea waves. Most of wave information is filtered out by the 2-D spatial spectrum analytics. Then the characteristic information of ocean fronts is extracted by digital image processing technology. Thus, information processing means by which characteristic information of ocean fronts can be extracted from SAR images is constructed.