ACOUSTIC PROPAGATION IN RANDOM OCEANS USING THE RADIATION TRANSPORT-EQUATION

A new theoretical approach to the modeling of acoustic propagation in randomly fluctuating oceans has been developed based on radiation transport equations which describe the evolution of the mutual coherence function of the acoustic pressure field. A general computer program has been developed to implement this theory for a large class of scattering models, including volume scattering by random internal waves and rough surface scattering by fully developed seas or long wavelength ocean swells. The radiation transport code at present deals with CW signals in two spatial dimensions and is used to calculate transmission loss. It has been applied to the problem of surface duct propagation with special emphasis on modeling the scattering out of the duct by random fluctuations and below duct ensonification. Comparisons have been made to a set of experimental data reported by Pedersen and Gordon [J. Acoust. Soc. Am. 37, 105–118 (1965)], with generally excellent results. © 1979, Acoustical Society of America. All rights reserved.