Time-warping in underwater acoustic waveguides

Abstract

The traditional way to isolate fixed mode number contributions to a transient wavefield in an underwater acoustic waveguide involves measuring the wavefield on a dense water-column-spanning vertical array and exploiting orthogonality over depth of the modes at each frequency. Recently it has been demonstrated that essentially the same goal can be accomplished in an ideal shallow water waveguide using measurements made on an isolated receiver by employing a signal processing technique known as time-warping. Time-warping makes use of a special nonuniform temporal sampling of the measured signal for which contributions from individual mode numbers are isolated in the frequency spectrum of the time-warped signal. The time-warping transformation in a general underwater acoustic waveguide is derived here. The general time-warping transformation is shown to reduce to the ideal shallow water waveguide time-warping transform as a special case. Use of the general time-warping transformation is illustrated with simulations in both a mid-latitude deep ocean environment and a high-latitude environment.

Document Details

Document Type
Pub Defense Publication
Publication Date
Feb 01, 2020
Source ID
10.1121/10.0000693

Entities

People

  • Michael G. Brown

Organizations

  • Office of Naval Research
  • University of Miami

Tags

Fields of Study

  • Engineering
  • Physics

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Systems Analysis and Design
  • Wave Propagation and Nonlinear Chaotic Dynamics.