Advanced

The dynamics of the bottlenose dolphin sonar beam.

Starkhammar, Josefin LU ; Kuczaj, Stan A; Amundin, Mats; Nilsson, Johan LU ; Almqvist, Monica LU and Persson, Hans W LU (2008) In Journal of the Acoustical Society of America 124(4).
Abstract
Much research on dolphin echolocation has focused on animals that have been trained to remain stationary or to carry a device that allows the animals to move but restricts the location of the sonar beam. In such cases, a small number of hydrophones measures sonar characteristics while dolphins solve echolocation tasks. As a result, much is known about the beam axis but relatively little is known about other parts of the beam. One reason for this disparity is that it has been difficult to interpret the results from off axis measurements using a small number of hydrophones (that may or may not sample simultaneously). In this paper, we report results from a system of 47 hydrophones in a 0.75 x 0.75 m(2) matrix that allowed measurements to be... (More)
Much research on dolphin echolocation has focused on animals that have been trained to remain stationary or to carry a device that allows the animals to move but restricts the location of the sonar beam. In such cases, a small number of hydrophones measures sonar characteristics while dolphins solve echolocation tasks. As a result, much is known about the beam axis but relatively little is known about other parts of the beam. One reason for this disparity is that it has been difficult to interpret the results from off axis measurements using a small number of hydrophones (that may or may not sample simultaneously). In this paper, we report results from a system of 47 hydrophones in a 0.75 x 0.75 m(2) matrix that allowed measurements to be made at multiple locations in the beam simultaneously, with a sample rate of 1 Msamples. The system both visualizes and records echolocation clicks in real time across the whole cross section of the beam, hence allowing the full dynamics of the sonar beam to be revealed. As a demonstration of the system's utility, we present results obtained with the system to assess the acoustic properties of clicks produced spontaneously by free-swimming dolphins. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of the Acoustical Society of America
volume
124
issue
4
publisher
American Institute of Physics
external identifiers
  • pmid:19063195
ISSN
1520-8524
DOI
10.1121/1.4782881
language
English
LU publication?
yes
id
14386033-c820-41ed-9a3d-f13b035bb19e (old id 1276338)
date added to LUP
2009-01-19 11:32:48
date last changed
2016-04-16 01:33:24
@article{14386033-c820-41ed-9a3d-f13b035bb19e,
  abstract     = {Much research on dolphin echolocation has focused on animals that have been trained to remain stationary or to carry a device that allows the animals to move but restricts the location of the sonar beam. In such cases, a small number of hydrophones measures sonar characteristics while dolphins solve echolocation tasks. As a result, much is known about the beam axis but relatively little is known about other parts of the beam. One reason for this disparity is that it has been difficult to interpret the results from off axis measurements using a small number of hydrophones (that may or may not sample simultaneously). In this paper, we report results from a system of 47 hydrophones in a 0.75 x 0.75 m(2) matrix that allowed measurements to be made at multiple locations in the beam simultaneously, with a sample rate of 1 Msamples. The system both visualizes and records echolocation clicks in real time across the whole cross section of the beam, hence allowing the full dynamics of the sonar beam to be revealed. As a demonstration of the system's utility, we present results obtained with the system to assess the acoustic properties of clicks produced spontaneously by free-swimming dolphins.},
  articleno    = {2506},
  author       = {Starkhammar, Josefin and Kuczaj, Stan A and Amundin, Mats and Nilsson, Johan and Almqvist, Monica and Persson, Hans W},
  issn         = {1520-8524},
  language     = {eng},
  number       = {4},
  publisher    = {American Institute of Physics},
  series       = {Journal of the Acoustical Society of America},
  title        = {The dynamics of the bottlenose dolphin sonar beam.},
  url          = {http://dx.doi.org/10.1121/1.4782881},
  volume       = {124},
  year         = {2008},
}