AN INVERSE METHOD FOR RECONSTRUCTING THE ACOUSTICAL IMPEDANCE OF A LAYERED OCEAN BOTTOM

The inverse method to infer the profiles of acoustical parameters under the sea-bottom from exact solutions of the wave equation is generally not applicable to the situation where discontinuity exists in the acoustical impedance profile¹. However, the ray approximation is still effective, and satisfactory results have been obtained under some practial circumstances^2,3.
In this paper a scattering inverse method is presented based on the equi-thickness (measured in the propagation time) division of the sub-bottom media. This program is capable of judging the existence of multireflections and eliminating their influence. The problems of the occurence of pseudo-boundaries rising from multi-reflections and computation errors caused by them have been preliminarily solved.