A Physically Consistent Speckle Model for Marine SLC SAR Images

A new physically based speckle model for marine single-look complex (SLC) synthetic aperture radar (SAR) images is here presented and investigated. The model allows using full-resolution SAR images instead of multilook SAR images, in which, at the expense of a coarser spatial resolution, the speckle is mitigated. The model is based on the three-parameters generalized-K (GK) probability density function (pdf). GK pdf is a suitable physically-based speckle model for marine SAR images ensuring a continuous and physically consistent transition among different scattering scenarios. This speckle model embodies Rayleigh, K, and Rice scattering scenes which are typical of marine scenes. The use of the three parameters, related to the GK pdf ones, is able to highlight the presence of both low backscattering areas and areas in which a small dominant scatterer is present. This is operationally interesting in SAR oil spill detection procedures.