SAS imaging of proud and buried targets at search frequencies

Frequencies of experimental synthetic aperture sonars (SAS) have varied from relatively low, with the goal of detecting and imaging buried targets, to relatively high to provide high resolution images of proud targets and bottom structure. This paper describes circular SAS studies at ARL:UT using recently acquired, highly controlled data which allows processing with arbitrary sonar parameters against both proud and buried targets. The nature of the data supports circular SAS apertures up to 360 degrees, corresponding to reflection tomography. SAS algorithms have been applied with both proud and buried target data to produce images as a function of target aspect for selected sonar parameters. Examples indicate effects of choice of sonar parameters on imaging for discrimination, classification, and identification.