Abstract: A computer apparatus determines a highly accurate displacement of a sonar array in real time using multiple processors and data objects. The processors receive multiple sonar pings from a sonar array, instantiate the quasi-unique sonar objects, beamform, and update the objects using time-delay functions. Each object includes properties such as a time of flight value associated with a first ping, time-delay values associated with a second ping, a speed of sound value associated with the pair of consecutive pings, a sonar beam angle value associated with the first ping, and the displacement value. Processing code in each object utilize these properties to update the displacement value and provide it for SAS imaging.

Abstract: To evaluate the resolution of individual sonar images in field conditions without specific targets, a statistical sampling of the imagery is taken and analyzed. Large quantities of resolution measurements are made on point-objects identified in the imagery. The measurements are compared to improve fidelity and generate statistically significant results. The image is broken into segments for analysis to identify variation in resolution across the image. The mean value of point-target resolution per segment can be determined for the imagery. A segment with an insufficient number of measurements required to determine a statistically significant value for resolution is rejected. The image resolution can be determined as the mean or median value of the segment measurements for the entire image.