Abstract
The Kirchhoff model expresses a relation between acoustic backscattering and seafloor characteristics and roughness especially for angles near normal incidence. In Sea Beam with equivalently 16 narrow acoustic beams, each beam has grazing angle from 70° to 90°, which is the range within which its approximation gives better results. Parameters of seafloor characteristics and roughness is capable to treat as a nonlinear inversion problem. This problem was solvable using BFGS formula replacing it into a forward problem. This method was applied to backscattering data collected from Japan Trench, Hachijo Depression and Mikura Basin using Sea Beam , and its usefulness for acoustical remote sensing of seabeds was confirmed.
