Interferometric side scan sonar : a tool for high resolution sea floor exploration
Résumé
This paper concerns the description of an a commercial interferometric sonar and possible applications for objects or for wrecks investigation. It presents general concepts of interferometry and its limit essentially due to noise. The main problem of interferometry which is a method echo triangulation is handicapped by its phase ambiguity because it measures a time delay between two sensors modulus a wavelength. So it exists different methods to remove the bias. The Gesma bought a interferometric prototype sonar 3 years ago and developped a general process to reduce to errors of bias. This tool is well designed for sea floor exploration because it provides an high resolution side scan sonar image with the same resolution bathymetry coming from the interferometric sensors. The main conclusion of this paper concerns the potential application of this sonar and the associated process to investigate with a fine resolution, wrecks, small objects, pipes. The speed of survey allows to use it on large areas. The quality of datas makes possible D reconstruction and an interactive visualisation.