Influence of ocean bottom reflection on ray chaotic behaviors in underwater acoustics

The influence of ocean bottom reflection on ray chaotic behaviors is investigated in the parabolic ray system that includes nonlinear sound-speed profile,internal waves,and ocean bottom reflection.Nonlinear dynamic methods including Poincare map and Lyapunov exponent are employed to describe the ray dynamic behaviors.The results show that the sound speed perturbation caused by internal waves may result in ray chaos and create larger chaotic regions.Ocean bottom reflection significantly influences nonlinear interactions among sound speed distribution,internal wave perturbation,and ray propagation.A decrease of ocean depth may broaden the chaotic ray regions,however, an excessively decrease of depth would decrease nonlinear interactions and thus chaotic regions of the ray system. We conclude that ocean bottom reflection plays an important role in affecting ray nonlinear behaviors in underwater acoustics.