Side scan sonar using phased arrays for high resolution imaging and wide swath bathymetry

The design of a new bathymetric sidescan sonar dedicated to the survey of the continental shelf is described. It uses linear phased arrays in order to perform dynamically the control of the resolution through the focusing of the beams, and beam steering to compensate for yaw and pitch. The 4 m long array, working at 112 kHz, yields high resolution imaging. In addition, an interferometric doublet, with a 2λ spacing, provides a wide swath bathymetric capability. Both functions take advantage of a fast digital pulse compression process. Results of sea trials with the hull mounted system (high resolution images and topographic maps) are discussed