Funded by an Office of Naval Research
Ocean Acoustics Entry-Level Faculty Award
Dates: April 2002 - September 2005
Abstract
The goal of this project is to develop statistical models and robust
estimation techniques for broadband mode signals propagating in
fluctuating ocean environments. In deep water the low-order modes
constitute some of the most energetic arrivals at long ranges.
Analysis of both simulated and experimental data indicates that, for
ranges on the order of megameters, these arrivals have a complicated
structure due to internal-wave-induced coupling. Understanding the
mechanisms and effects of mode coupling is a prerequisite for using
the mode signals in applications such as tomography or matched field
processing. Building on the results of the Acoustic Thermometry of
Ocean Climate Experiment, this research synthesizes three topics in
underwater acoustics: environmental characterization, signal
processing, and propagation modeling. The specific objectives of the
proposed project are: to characterize mode wavenumber and shape
fluctuations associated with temperature changes; to develop robust
signal processing techniques for broadband mode estimation; and to
investigate stochastic models of mode coupling due to internal waves.
Analysis of environmental and acoustic data collected during the North
Pacific Acoustic Laboratory experiment is an integral part of this
research.