Statistical properties of L-band sea clutter measured with a polarimetric synthetic aperture radar

The limiting factor affecting the performance of most airborne radar systems in detecting targets on or near the surface of the sea is return echoes from the sea surface or sea clutter. The objective of this paper is to provide an analysis of the statistics of Australian sea clutter for an L-band VV-polarised airborne radar system from sampled measured values. Polarimetric synthetic aperture radar (POLSAR) image of the North-West region of Australia, acquired in 1996 by the Jet Propulsion Laboratory (JPL) was used to study, the backscattered statistics of the sea surface. Using this POLSAR image, a number of different candidate distribution functions have been investigated, and their goodness-of-fit have been carried out using the Kolmogorov Smirnov goodness-of-fit test. The log-normal, Weibull and K-distributions have been applied to model the statistical properties of multi-look polarimetric SAR sea clutter. The K-distribution has been found to have good agreement with the observed sea clutter intensity distributions.

1. INTRODUCTION

One of the most challenging problem in target detection is reliable detection in high clutter background. This problem is of particular interest for Medium Pulse Repetition Frequency (MPRF) radar which has significant clutter return in the antenna side lobes. The variability of the clutter return from terrain and sea limits the radar target detection capability.