|Underwater passive acoustic localization of Pacific walruses in the northeastern Chukchi Sea|Rideout, B.P.; Dosso, S.E.; Hannay, D.E. (2013). Underwater passive acoustic localization of Pacific walruses in the northeastern Chukchi Sea. J. Acoust. Soc. Am. 134(3): 2534-2545. hdl.handle.net/10.1121/1.4816580
In: The Journal of the Acoustical Society of America. American Institute of Physics: New York, etc. ISSN 0001-4966, more
acoustic signal processing, array signal processing, Bayes methods, biocommunications, biological techniques, maximum likelihood estimation, time-of-arrival estimation, underwater sound, zoology
|Authors|| || Top |
- Rideout, B.P.
- Dosso, S.E.
- Hannay, D.E.
This paper develops and applies a linearized Bayesian localization algorithm based on acoustic arrival times of marine mammal vocalizations at spatially-separated receivers which provides three-dimensional (3D) location estimates with rigorous uncertainty analysis. To properly account for uncertainty in receiver parameters (3D hydrophone locations and synchronization times) and environmental parameters (water depth and sound-speed correction), these quantities are treated as unknowns constrained by prior estimates and prior uncertainties. Unknown scaling factors on both the prior and arrival-time uncertainties are estimated by minimizing Akaike's Bayesian information criterion (a maximum entropy condition). Maximum a posteriori estimates for sound source locations and times, receiver parameters, and environmental parameters are calculated simultaneously using measurements of arrival times for direct and interface-reflected acoustic paths. Posterior uncertainties for all unknowns incorporate both arrival time and prior uncertainties. Monte Carlo simulation results demonstrate that, for the cases considered here, linearization errors are small and the lack of an accurate sound-speed profile does not cause significant biases in the estimated locations. A sequence of Pacific walrus vocalizations, recorded in the Chukchi Sea northwest of Alaska, is localized using this technique, yielding a track estimate and uncertainties with an estimated speed comparable to normal walrus swim speeds.