Bistatic reverberation benchmarking exercise: BiStaR versus analytic formulas

Abstract

The newly developed BiStaR range-dependent bistatic reverberation model is benchmarked against analytic formulas for bistatic reverberation intensity in range-dependent environments. The BiStaR model is based on the C-SNAP range-dependent normal mode propagation model with a narrow-band approximation time domain extension and a coherent patch interaction model. The code is also capable of producing incoherent reverberation predictions that here are directly compared to the analytic formulas. The analytic formulas have been derived using ray-based intensity formulas for propagation in range-dependent waveguides and a generalized class of Lambert law type scattering kernels. Comparison between the BiStaR and the analytic predictions show good agreement for a variety of range-dependent bistatic scenarios. Such agreement generates confidence in the closed form formulas, which are particularly valuable for generating insight into the simple mechanisms which control the dominant characteristics of range-dependent bistatic reverberation, and in the BiStaR model, which has been developed to model bistatic reverberation in 3-D environments with high resolution environmental characterizations. [Work supported by ONR and NATO SACLANT Undersea Research Centre.]