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 i n order to perform dynamically the control of the resolution through t he focusing of the beams, and beam steering to compensate for yaw and pitch. The 4m long array, working at 112kHz, yields high resolution im aging. In addition, an interferometric doublet, with a 2 lambda spacin g, provides a wide swath bathymetric capability. Both functions take a dvantage of a fast digital pulse compression process. Results of sea t rials with the hull mounted system (high resolution images and topogra phic maps) are discussed.