Development of Computational Tools for Predicting the Radar Scattering from Targets on a Rough Sea Surface

摘要

The radar scattering from 2D and 3D targets on a rough sea surface is investigated using computational techniques developed specifically for this problem. Numerical simulations and Monte Carlo studies yield insight into the scatter phenomenology. It is found that the scattering from a target on a random rough sea surface becomes more coherent as the incident field becomes more coherent, ie, for low wind speeds or low elevation angles. For the less coherent case, the average. and peak scattering levels of a target on a rough surface may be significantly higher or lower than for a flat surface, depending on the target geometry. A tilted plan model is proposed for predicting the variations in the RCS of a target on a rough sea surface by mounting the target on a locally planar surface which can tilt, similar to the two-scale composite model of ocean scattering. It is found that tilting the plane, or equivalent, rolling the target on a horizontal plane fields as much or more variation in the RCS than caused by the rough surface. However, the cross polarization introduced by the rough surface in 3D is not well predicted by the tilted plane model, nor is the unexplained behavior near the Brewster angle for vertical polarization.