Acoustic phase and amplitude of a signal transmitted through a uniform flow in the deep ocean

Abstract

Results of a previous hydrodynamical study of a uniform, deep‐ocean flow are used to develop simple approximations to the sound‐speed and current distributions in the flow. The behavior of sound speed with depth, surface current, and source and receiver locations is examined. The effects of the flow on ray geometry, travel time, and spreading loss are investigated for a surfaced cw sound source and bottomed receiver. Total‐field amplitude and phase are determined and are found to be highly sensitive to surface‐current variations and to source and receiver locations. A simple method is presented for accurately estimating amplitude and phase. Then, an approximate phase formula is developed that is proportional to surface current, linear in source location, and sinusoidal in the orientation angle of the source–receiver range.Subject Classification: [43]30.20; [43]28.60.