NPS high resolution synthetic aperture sonar

Abstract

This thesis investigated the use of synthetic aperture techniques to achieve a long effective aperture, high resolution, imaging sonar. The approach included a full simulation of the system using the MATLAB programming environment that provided a model for developing six data processing algorithms and a working 25KHz, 1 m baseline, air medium synthetic aperture sonar. The six azimuthal processing techniques included: (1) a normal, real aperture, (2) an unfocussed synthetic aperture, (3) a hybrid focussed-unfocussed system, (4) a fully focussed one line algorithm, (5) a limited two-dimensional, fully focussed algorithm and, (6) a limited two-dimensional, hybrid focussed-unfocussed algorithm. This thesis compared the run times, resolutions and signal to noise ratios achieved by the six techniques both in simulation and experimental measurements collected with the actual prototype.