Statistical analysis of azimuth streaks observed in digitally processed CASSIE imagery of the sea surface

During the Canberra synthetic-aperture radar sea imaging experiment in 1987 (CASSIE 87), numerous azimuth streaks were observed by the X-band SAR. The authors analyzed the first- and second-order statistical properties of the CASSIE data, containing the images of the sea surface where wave breaking is considered to be present. The probability density function (PDF) and higher order intensity moments are first analyzed for image areas containing few and many streaks. The theoretical PDFs that fit the measured PDFs are identified. The two-dimensional intensity autocorrelation functions (ACFs) of images processed at different processor focal settings are computed and discussed to identify the predominant scatterers´ motions. From these experimental results, a scattering model is postulated to account for the non-Rayleigh distribution and correlation of scattering amplitude, and the motion of scatterers. Using the model, the ACF of the range radar cross section is estimated from the image ACF and attempts are made to predict the azimuth component of the image ACF and the scene coherence time