Statistical Analysis of Multistatic Echoes From a Shipwreck in the Malta Plateau

False alarms arising from sonar clutter are one of the primary limitations to the use of active sonar in shallow-water environments. A statistical analysis of experimental data obtained for one type of clutter-echoes from a shipwreck-is presented in this paper. In the experiment, multistatic sonar measurements of a shipwreck were taken at three different ranges, over a wide variety of aspect angles and bistatic angles. The echo envelope statistics were characterized in terms of the K-distribution shape parameter (α) with an average value of approximately 2 measured for the closest range. While smaller values of α were observed at beam aspects, variations with range and bistatic angle were predominantly explained by related variations in signal-to-noise ratio (SNR). Additionally, estimates of α from each range were seen to be log-normally distributed, including the variation with aspect and SNR.