OPEN ACCESS
All odontocetes produce short acoustic pulses called clicks to perform localization, hunt preys or communicate. These clicks are generally emitted in trains having a certain rhythm. Frequently, click trains from several animals are recorded simultaneously. This paper introduces a method for deinterleaving these click trains with a single hydrophone. As final results it gives the number of animals clicking simultaneously and allows the tracking of rhythm variations within each train. The proposed algorithm is successfully tested on simulated data and validated on real data.
RÉSUMÉ
Tous les odontocètes émettent de courtes impulsions acoustiques (clics) pour satisfaire une activité de localisation, de chasse ou de communication. Ces impulsions sont le plus souvent émises en trains rythmés. Il est très fréquent d’enregistrer simultanément les clics de plusieurs animaux. Cet article présente une méthode permettant de séparer les trains de clics enregistrés sur un unique hydrophone afin de connaître le nombre d’animaux ayant émis simultanément. La méthode proposée est testée avec succès sur des données simulées et sur des données réelles.
click train, deinterleaving, time-period analysis, rhythm, inter-click interval
MOTS-CLÉS
trains de clics sonar, désentrelacement, analyse de rythme, intervalle inter-clic
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