Imaging multi armonico applicato allo studio del fondale marino (Multifrequency imaging applied to the characterization of the seafloor)

In this article some non-linear propagation principles are described. These are well known in medical field: we propose to apply those to the underwater domain. Actually, the use of second harmonic generated by the non-linear propagation is applied to improve diagnostic acoustical imaging resolution [1-5]. The frequency diversity provides essential information to derive the nature of the seafloor. Instead of using several different sonar systems at the same time, a single nonlinear source allows the multi-frequency responses to be inherently perfectly matched both in time and in space.