Influence of the nonlinear wave interactions and wind saturation over the radar backscattering

Since SAR mapping is nonlinear, the input data of the SAR processor must be known accurately as possible, because a simple change of magnitude of the RAR images can lead to very different SAR images. The hydrodynamic modulation remains the less known contribution of the SAR mapping and it is difficult to estimated it because the transfer function is usually derived from the action conservation and implies unknown source functions. The authors discuss an alternative weakly nonlinear model of wave-wave interactions and which does not take into account all hydrodynamic modulations (for instance wind-wave interactions) which explains especially the change of slope observed in the spectrum slope.