4aUW2. Bottom interactions of pulse propagation and corresponding real-time reverberation.

Session: Thursday Morning, May 16

Time: 8:30

Author: Kevin B. Smith
Location: Dept. of Phys., Code PH/Sk, Naval Postgrad. School, Monterey, CA 93943


A simple, memory-intensive algorithm using a split-step Fourier cw PE model to compute the time-domain animation of a pulse has been developed. By examining such an animation in the presence of a rough, deep ocean bottom, the significance of secondary multipaths on predicted reverberation returns was found to be non-trivial. The existence and relative magnitude of these secondary arrivals has been confirmed in measured data. An additional algorithm has recently been developed to compute the exact two-way travel times associated with bottom interface reverberation by convolving the one-way travel times from the source and the receiver. Presented here is a simultaneous visualization of the one-way pulse propagation and the corresponding two-way reverberation. To determine the influence of the secondary multipaths on reverberation, the bottom has been altered in the near field to remove the multipath influence. This also shows the errors encountered in predicting reverberation when only the incident field is computed. [Work supported by ONR.]

from ASA 131st Meeting, Indianapolis, May 1996