On the Statistics of Sea Clutter
NAVAL RESEARCH LAB WASHINGTON DC
Pagination or Media Count:
A model for the statistics of sea clutter has been developed from scattering theory and the composite surface-scattering model. The model postulates that sea clutter is exponentially Rayleigh envelope distributed for glassy seas and should tend toward the lognormal distribution in particular for horizontal polarization with increasing roughness. The lognormality of sea clutter arises from the tilting of the slightly rough patches by the large-scale roughness undulating surface. An empirical identification of the statistics of sea clutter taken with the Four-Frequency Radar system shows that in general the distribution of sea clutter is intermediate between the exponential Rayleigh envelope and the lognormal distribution. However, for calm seas and small sample sizes less than about 200 independent samples the distribution of sea clutter may be approximated by either the exponential or the lognormal distribution. The first five central moments of sea clutter in decibels have been calculated for moderate and rough sea conditions.
- Statistics and Probability
- Active and Passive Radar Detection and Equipment