Technical Information

dBSeaPE — parabolic equation method

The dBSeaPE solver makes use of the parabolic equation method, a versatile and robust method of marching the sound field out in range from the sound source. This method is one of the most widely used in the underwater acoustics community, and offers excellent performance in terms of speed and accuracy in a range of challenging scenarios.

dBSeaRay — ray tracing method

The dBSeaRay solver forms a solution by tracing rays from the source to the receiver. A large number of rays leave the source covering a range of angles, and the sound level at each point in the receiving field is calculated by summing the energy arriving from each ray. Seabed interaction uses a complex reflection coefficient from the layered sediment, so ray amplitudes account for the sediment properties on each bottom bounce.

dBSeaPE 3D and dBSeaRay 3D — full three-dimensional solvers

The 2D solvers above calculate the field in vertical slices radiating from each source, so sound cannot bend around islands, headlands or steep bathymetry. The 3D solvers remove that limitation. dBSeaPE 3D marches the parabolic equation in range, depth and azimuth at once, using a horizontal Padé expansion to capture out-of-plane propagation, and treats land within the domain as a boundary rather than stopping the march. dBSeaRay 3D traces rays in three dimensions, so a ray leaving the source at one bearing can arrive at a receiver on another. The 3D solvers are recommended for most work; the 2D solvers remain available for older projects and simple open-water scenarios.

Rapid solvers

Three simple spreading-law solvers (20 log, 10 log and a user-defined A·log₁₀ r + B·r) are included for quick evaluation of a problem before running a full propagation model.