Nonlinear multi-frequency transmitter for seafloor characterization

To gather with a single surveying tool the backscatter frequency response of the seafloor would be a large asset to characterize the nature of the bottom. One proposes to take advantage of the saturation effect occurring with a high powered source: numerous harmonic waves are created by non linear interactions along the propagation. The feasibility of a multi-frequency source that is adapted to seafloor characterization is investigated. In a preliminary approach, a pseudo-1D model is used to estimate the on-axis levels of the first multiple frequencies. Experimental measurements performed with two typical geometries of transducers are compared with simulations.