Model Measurements of Sound Propagation in Water of Randomly Fluctuating Speed of Sound

Scale model measurements of volume reverberation in the ocean are conducted in a water tank containing randomly distributed zones of different speed of sound. A measuring method of comparing the scattered sound signal with an undisturbed signal permits the measurement of fluctuations not only of the amplitude but also of the phase with the required accuracy. The mean-square values of amplitude and phase and the spatial crosscorrelation coefficient of the fluctuations are determined for various source-receiver separations and acoustic frequencies. The results are compared with the present theory on sound propagation in a weak inhomogeneous medium.