Application of the K+Rayleigh distribution to high grazing angle sea-clutter

The probability distribution of the radar backscatter is commonly used to determine the threshold for separating targets from clutter. Analysis of sea-clutter data collected at high grazing angles, between 15° and 45°, by the Defence Science Technology Organisation (DSTO) Ingara fully polarimetric X-band radar has been used extensively to test distribution models given a large number of samples. The focus of this paper is to determine the most appropriate sea-clutter model for high grazing angle sea-clutter given the smaller number of samples in a typical target detection scenario. For this purpose, a recently proposed K+Rayleigh distribution is introduced to account for the extra Rayleigh scattering observed in the radar backscatter.