Simulator for underwater 3D acoustic imaging

This paper presents a simulator for a forward looking 3D imaging sonar. The array architecture consists of two uniform linear arrays, one transmitter and the other receiver, which are placed orthogonally to each other in T shape. The underwater scene is ensonified either by bandlimited chirp transmitted sequentially one for each elevation beam or simultaneously for all beams using coded waveforms one for each beam. The surface of the object is modelled using small triangular facets and their combined response is gathered as echoes at the receiver using Kirchoff's scattering law. The 3D image is reconstructed using elevation, azimuth and range information obtained through receiver processing of the echoes. The simulator allows the study of the array architecture and use of sequential and coded waveform transmission and is useful design to refine the design and study the performance in controlled setting.