Impacts of Environment-Dependent Acoustic Propagation on Passive Acoustic Monitoring of Cetaceans

PDF

Authors
  1. Binder, C.M.
Corporate Authors
Defence Research and Development Canada, Atlantic Research Centre, Halifax NS (CAN)
Abstract
Significant effort has been made over the last few decades to develop automated passive acoustic monitoring (PAM) systems capable of classifying cetaceans at the species level; however, these systems often require tuning when deployed in different environments. Anecdotal evidence suggests that this requirement to adjust a PAM system’s parameters is partially due to differences in the acoustic propagation characteristics. The environment dependent propagation characteristics create variation in how a cetacean vocalization is distorted after it is emitted. If these difference are not accounted for it could reduce the performance of automated PAM systems. An aural classifier developed at Defence R&D Canada (DRDC) has been used successfully for inter-species discrimination of cetaceans. Accurate results are obtained by using perceptual signal features that model the features employed by the human auditory system. In this thesis, a combination of an at-sea experiment and simulations with modified bowhead and humpback whale vocalizations was conducted to investigate the robustness of the classifier performance to signal distortion as a function of propagation range. It was found that in many environments classification performance degraded with increasing range, largely due to decreased signal-to-noise ratio (SNR); however, in some environments as much as 40% of the performance reduction was attributed to signal distortion resulting from environment-dependent propagation. It was
Keywords
Passive acoustic monitoring;cetaceans;acoustic propagation;ocean acoustics;detection and classification
Report Number
DRDC-RDDC-2017-P060 — External Literature
Date of publication
02 Nov 2017
Number of Pages
196
DSTKIM No
CA045280
CANDIS No
805679
Format(s):
Electronic Document(PDF)

Permanent link

Document 1 of 1

Date modified: