Fourier synthesis of three-dimensional scattering in a two-dimensional oceanic waveguide using boundary integral equation methods

A numerical method is presented for computing the three-dimensional pressure field generated by compact harmonic sources in a two-dimensional stratified acoustic waveguide. This method can serve to model acoustic scattering from ridgelike bathymetry, or surface features such as ice ridges, in a realistic oceanic waveguide model. The basic technique entails synthesizing the three-dimensional solution by using Fourier transform methods based on a sequence of two-dimensional problems. Numerical results from computations based on a simple cosine-bell ridge model and a more complex ice model are presented, and a comparison with the analogous strictly two-dimensional model is also considered.