Geoacoustic Inversion Using Physical–Statistical Bottom Reverberation Model in the Deep Ocean

Reverberation is an important ocean phenomenon that involves bottom properties. This paper proposes a method of geoacoustic inversion using bottom reverberation in the deep ocean. Models for the probability density function, including Rayleigh, Lognormal normal, K, and Weibull distributions, are commonly used to describe the envelope of bottom reverberation. Based on the measured data in South China Sea, the envelope of bottom reverberation in the experiment is consistent with K distribution. A double exponential distribution is used to generate the amplitude of reverberation, of which the envelope obeys the K distribution. In addition, the propagation and scattering models are introduced as the parameters of double exponential function, wherein the model has a physical mechanism. Therefore, a bottom reverberation model with both physical and statistical characteristics is suitable for geoacoustic inversion. The cost function is used to minimize the mean square difference between the measured and modeled envelope of the bottom reverberation. The inversion results are consistent with those from previous research.