Acoustic Modeling for Volumetric Sonar Systems

Volumetric synthetic aperture sonar systems image scenes used to create three-dimensional imagery of the seabed sub-bottom. Modeling and simulation is helpful in both the design of these sensors and the prediction of performance - especially in complex environments. A point-based sonar signal model (PoSSM) has been configured to replicate recent experiments in a test environment with a layered sediment bed. This model includes diffuse (incoherent) and specular (coherent) interface scattering from sediment interfaces and diffuse volumetric scattering. Modeling results are quantitatively compared to field data and good agreement is shown near the sediment interfaces. The agreement within the sediment volume is worse, likely owing to sediment inhomogeneities (e.g. embedded rocks) and texture not represented by the model.