Time-evolution modeling of seafloor scatter. II. Numerical and experimental evaluation

A time-evolution model of seafloor scatter is numerically implemented and experimentally evaluated. The model is based on analytically expressing the elementary time-backscattered response of every seafloor surface and every seafloor volume infinitesimal element. The implementation of the model is based on a statistical realization of the seabed interface and volume inhomogeneities, from which the time series are computed by coherent summation of the scatter from small elements over the insonified area and volume. The analytical expressions and the implementation are evaluated for the image solution case, for which an almost perfect agreement is found. Examples are shown of how the beam width and seabed roughness affect the time-series return from both the surface and from the volume. The results of the model are compared with data from two different bottom types recorded with a parametric sonar. Reasonable accordance is found between the model and the data.