SPATIAL HORIZONTAL COHERENCE OF SOUND IN SHALLOW-WATER

A theory for the problems of spatial horizontal coherence of a sound field in shallow water was developed by using the concept of horizontal rays and vertical modes, and by adiabatic approximation. Both analytical and numerical results were presented for transverse coherence of sound in a shallow sea under summer and winter conditions, and the results were compared with those of measurements. Analysis showed that the higher-ordered modes are more sensitive to the disturbance of boundaries, but the sound-speed disturbance has similar influence on all modes; and that the absorption of the bottom has a significant influence on the range-dependent properties of coherence of sound in winter conditions.