Of Rats and Men: Underwater Passive Acoustic Localization Investigations Using Relative Arrival Times and Blind Channel Estimation
Date
2022
Authors
Contributor
Advisor
Department
Instructor
Depositor
Speaker
Researcher
Consultant
Interviewer
Narrator
Transcriber
Annotator
Journal Title
Journal ISSN
Volume Title
Publisher
Volume
Number/Issue
Starting Page
Ending Page
Alternative Title
Abstract
Understanding the ecology of any organism requires an understanding of all its life stages. Underwateracoustics provides the ability to observe the submerged lives of marine mammals in ways not possible
through visual means. The complexities of underwater acoustic propagation yield both challenges and
opportunities to extract information from recorded data, of which the estimation of underwater location is
one example. This dissertation presents two signal processing approaches related to passive underwater
acoustic localization.
Blind channel estimation is a computational approach to estimating a set of impulse responses basedon simultaneous recordings of the same unknown source by different receivers. The estimated impulse
responses from this approach may simplify passive acoustic localization for some types of sound sources
by making arrival times easier to identify. Differences among the received waveforms are interpreted as
evidence of differences in the underlying channel impulse responses. Using a sparse assumption on these
impulse responses, several different optimization approaches (OMP, CoSaMP, and NESTA) are applied to
simulated ocean acoustic data. Estimated channels are a good fit to the true channel when the channels are
static, but the introduction of a time-varying characteristic to the true channels negatively impacts channel
recovery performance.
Single hydrophone passive acoustic localization is the practice of estimating location characteristics of anunderwater sound source using acoustic recordings from a single receiver. This work develops an approach
for estimating the horizontal range between a submerged source and receiver in a deep ocean environment
without relying on modal dispersion. We develop a cost function and optimization approach that are
robust to some significant sources of noise and environmental uncertainty. Results from simulations and
ground-truthed measured data demonstrate the accuracy of this localization approach.
Underwater acoustic data recorded by the ALOHA Cabled Observatory (ACO) are processed using thissingle hydrophone localization approach. Acoustic recordings at ACO made between February 2007 -
September 2017 yield 41,481,171 fin whale 20 Hz call detections, of which 3,445,568 detections remain after
pruning away suspected sei whale and duplicate call detections. Fin whale 20 Hz calls are concentrated
in the November-April time period near ACO. Estimated fin whale call parameters, including inter-call
interval, are more clearly estimated from the recorded data following pruning to reduce the false positive
rate.
Description
Keywords
Acoustics, Biological oceanography, blind channel estimation, fin whale, localization, underwater acoustics
Citation
Extent
224 pages
Format
Geographic Location
Time Period
Related To
Related To (URI)
Table of Contents
Rights
All UHM dissertations and theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission from the copyright owner.
Rights Holder
Local Contexts
Collections
Email libraryada-l@lists.hawaii.edu if you need this content in ADA-compliant format.