Underwater acoustic localization and tracking of Pacific walruses in the northeastern Chukchi Sea
This thesis develops and demonstrates an approach for estimating the three-dimensional (3D) location of a vocalizing underwater marine mammal using acoustic arrival time measurements at three spatially separated receivers while providing rigorous location uncertainties. To properly account for uncer...
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ftuvicpubl:oai:dspace.library.uvic.ca:1828/3790 2023-05-15T15:54:32+02:00 Underwater acoustic localization and tracking of Pacific walruses in the northeastern Chukchi Sea Rideout, Brendan Pearce Dosso, Stanley Edward 2012 application/pdf http://hdl.handle.net/1828/3790 English en eng http://hdl.handle.net/1828/3790 Available to the World Wide Web passive acoustic localization Pacific walrus Chukchi Sea Bayesian ABIC localization uncertainty analysis ray tracing Thesis 2012 ftuvicpubl 2022-05-19T06:13:00Z This thesis develops and demonstrates an approach for estimating the three-dimensional (3D) location of a vocalizing underwater marine mammal using acoustic arrival time measurements at three spatially separated receivers while providing rigorous location uncertainties. To properly account for uncertainty in the measurements of receiver parameters (e.g., 3D receiver locations and synchronization times) and environmental parameters (water depth and sound speed correction), these quantities are treated as unknowns constrained with prior estimates and prior uncertainties. While previous localization algorithms have solved for an unknown scaling factor on the prior uncertainties as part of the inversion, in this work unknown scaling factors on both the prior and arrival time uncertainties are estimated. Maximum a posteriori estimates for sound source locations and times, receiver parameters, and environmental parameters are calculated simultaneously. Posterior uncertainties for all unknowns are calculated and incorporate both arrival time and prior uncertainties. Simulation results demonstrated that, for the case considered here, linearization errors are generally small and that the lack of an accurate sound speed profile does not necessarily cause large uncertainties or biases in the estimated positions. The primary motivation for this work was to develop an algorithm for locating underwater Pacific walruses in the coastal waters around Alaska. In 2009, an array of approximately 40 underwater acoustic receivers was deployed in the northeastern Chukchi Sea (northwest of Alaska) from August to October to record the vocalizations of marine mammals including Pacific walruses and bowhead whales. Three of these receivers were placed in a triangular arrangement approximately 400 m apart near the Hanna Shoal (northwest of Wainwright, Alaska). A sequence of walrus knock vocalizations from this data set was processed using the localization algorithm developed in this thesis, yielding a track whose estimated swim speed is ... Thesis Chukchi Chukchi Sea Alaska walrus* University of Victoria (Canada): UVicDSpace Chukchi Sea Hanna Shoal ENVELOPE(-162.000,-162.000,72.000,72.000) Pacific |
institution |
Open Polar |
collection |
University of Victoria (Canada): UVicDSpace |
op_collection_id |
ftuvicpubl |
language |
English |
topic |
passive acoustic localization Pacific walrus Chukchi Sea Bayesian ABIC localization uncertainty analysis ray tracing |
spellingShingle |
passive acoustic localization Pacific walrus Chukchi Sea Bayesian ABIC localization uncertainty analysis ray tracing Rideout, Brendan Pearce Underwater acoustic localization and tracking of Pacific walruses in the northeastern Chukchi Sea |
topic_facet |
passive acoustic localization Pacific walrus Chukchi Sea Bayesian ABIC localization uncertainty analysis ray tracing |
description |
This thesis develops and demonstrates an approach for estimating the three-dimensional (3D) location of a vocalizing underwater marine mammal using acoustic arrival time measurements at three spatially separated receivers while providing rigorous location uncertainties. To properly account for uncertainty in the measurements of receiver parameters (e.g., 3D receiver locations and synchronization times) and environmental parameters (water depth and sound speed correction), these quantities are treated as unknowns constrained with prior estimates and prior uncertainties. While previous localization algorithms have solved for an unknown scaling factor on the prior uncertainties as part of the inversion, in this work unknown scaling factors on both the prior and arrival time uncertainties are estimated. Maximum a posteriori estimates for sound source locations and times, receiver parameters, and environmental parameters are calculated simultaneously. Posterior uncertainties for all unknowns are calculated and incorporate both arrival time and prior uncertainties. Simulation results demonstrated that, for the case considered here, linearization errors are generally small and that the lack of an accurate sound speed profile does not necessarily cause large uncertainties or biases in the estimated positions. The primary motivation for this work was to develop an algorithm for locating underwater Pacific walruses in the coastal waters around Alaska. In 2009, an array of approximately 40 underwater acoustic receivers was deployed in the northeastern Chukchi Sea (northwest of Alaska) from August to October to record the vocalizations of marine mammals including Pacific walruses and bowhead whales. Three of these receivers were placed in a triangular arrangement approximately 400 m apart near the Hanna Shoal (northwest of Wainwright, Alaska). A sequence of walrus knock vocalizations from this data set was processed using the localization algorithm developed in this thesis, yielding a track whose estimated swim speed is ... |
author2 |
Dosso, Stanley Edward |
format |
Thesis |
author |
Rideout, Brendan Pearce |
author_facet |
Rideout, Brendan Pearce |
author_sort |
Rideout, Brendan Pearce |
title |
Underwater acoustic localization and tracking of Pacific walruses in the northeastern Chukchi Sea |
title_short |
Underwater acoustic localization and tracking of Pacific walruses in the northeastern Chukchi Sea |
title_full |
Underwater acoustic localization and tracking of Pacific walruses in the northeastern Chukchi Sea |
title_fullStr |
Underwater acoustic localization and tracking of Pacific walruses in the northeastern Chukchi Sea |
title_full_unstemmed |
Underwater acoustic localization and tracking of Pacific walruses in the northeastern Chukchi Sea |
title_sort |
underwater acoustic localization and tracking of pacific walruses in the northeastern chukchi sea |
publishDate |
2012 |
url |
http://hdl.handle.net/1828/3790 |
long_lat |
ENVELOPE(-162.000,-162.000,72.000,72.000) |
geographic |
Chukchi Sea Hanna Shoal Pacific |
geographic_facet |
Chukchi Sea Hanna Shoal Pacific |
genre |
Chukchi Chukchi Sea Alaska walrus* |
genre_facet |
Chukchi Chukchi Sea Alaska walrus* |
op_relation |
http://hdl.handle.net/1828/3790 |
op_rights |
Available to the World Wide Web |
_version_ |
1766389749646360576 |