Simulation of Rippled-Sand Synthetic Aperture Sonar Imagery

Abstract

Simulation of Synthetic Aperture Sonar (SAS) imagery is of growing interest for training of both human operators and the 'supervised learning' of computer-aided detection / computer-aided classification (CADCAC) systems. Synthetic Aperture Sonar (SAS) imagery is often characterized by a decidedly non-Rayleigh amplitude distribution, owing to its inherent high-resolution combined with speckle, induced by the coherent image formation process. Effective simulation of SAS imagery must be both visually and statistically realistic. The method presented here has been developed to simulate rippledsand Sonar imagery at high-frequencies (i.e., on the order of 100 kHz), which accounts for non-symmetric ripple shape, sediment acoustic properties, Sonar to ripple orientation, system resolution, signal to noise ratio, and coherent imaging induced speckle. This numerical simulation method is computationally inexpensive, and compares well both visually and statistically with collected data over a wide range of orientation angles. Simulation methods are presented with validation against SAS imagery collected by the Naval Surface Warfare Center -Panama City Division.