REVSIM—A numerical model for simulating quasistationary, coherent, multibeam reverberation time series

Abstract

The REVSIM model produces quasistationary, coherent, multiplebeam reverberation time series which are functions of the sonar system (actual transmit/receive, horizontal/vertical beampatterns, pulse type, shape, length and power and sampling rate), platform (speed, depth, and direction) and environment (wind speed and direction, backscatterer strengths, and propagation loss). Volume, surface, and/or bottom reverberation as seen by a sonar on a moving platform are generated. The model first computes reverberation spectra for each beam based on a general formulation of Ol'shevskii. Optimal, all-pole approximations of the spectra are generated to an arbitrary degree of accuracy using modern linear spectral prediction techniques. The all-pole approximations are used to generate a set of linear, time-varying, digital filters with infinite impulse responses (IIR). The filters, when driven by stationary, white, Gaussian noise produce the quasistationary, coherent, multiple-beam reverberation time series. The principles underlying the model are given and an example is presented to illustrate the utility of the model in simulating system performance.