Empirical Bayes Estimation of the Probability Density of the Radar Cross Section of the Sea Surface.

摘要

When sea Clutter is viewed at low grazing angles with a high-resolution radar,the envelope of the return does not have a Rayleigh distribution. Based on the concept of the composite sea surface scattering model,the probability density of the return can be written as the integral of the product of two factors. The first factor is the probability density function of the radar cross section (RCS) of the illuminated patch,and the second is the density of the return conditioned on the cross section. If the patch is large,one can assume that the cross section remains constant. But for a small patch it varies randomly. Two sets of nonparametric estimates of the RCS density of a small patch were obtained. One group of estimates is based on experimental data and the other on a simulation consisting of theoretical models. Because the estimation procedures differ for the two groups,no statistical comparison was made;however,the two sets are considered in good agreement. (Author)