All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 139 18 0
PDF Downloads 26 18 0

A Signal-processing Scheme for Passive Acoustical Mapping of Breaking Surface Waves

Li DingDepartment of Electrical and Computer Engineering, University of Victoria, Victoria, British Columbia, Canada

Search for other papers by Li Ding in
Current site
Google Scholar
PubMed
Close
and
David M. FarmerInstitute of Ocean Sciences, Sidney, British Columbia, Canada

Search for other papers by David M. Farmer in
Current site
Google Scholar
PubMed
Close
Full access

Abstract

An acoustical system is described with emphasis on its signal-processing scheme. The system consists of a small broadband hydrophone array of span 8.5 m and 5-kHz bandwidth, which is able to track individual breaking surface waves by passive detection of the naturally generated sound of wave breaking. The generalized cross-correlation technique is used to determine time differences of acoustical signals from breaking waves arriving at the array. Breaking events are identified in correlation time sequences, and the identification is aided by image enhancement and pattern recognition. Determination of source positions from the estimated time delays is also discussed. The instrument was first employed during the Surface Wave Program (SWAPP), and preliminary results clearly demonstrate the ability to track individual breaking events. This system can be used to measure some spatial and temporal characteristics of breaking waves, such as frequency of breaking, lifetime, velocity, and spatial distributions.

Abstract

An acoustical system is described with emphasis on its signal-processing scheme. The system consists of a small broadband hydrophone array of span 8.5 m and 5-kHz bandwidth, which is able to track individual breaking surface waves by passive detection of the naturally generated sound of wave breaking. The generalized cross-correlation technique is used to determine time differences of acoustical signals from breaking waves arriving at the array. Breaking events are identified in correlation time sequences, and the identification is aided by image enhancement and pattern recognition. Determination of source positions from the estimated time delays is also discussed. The instrument was first employed during the Surface Wave Program (SWAPP), and preliminary results clearly demonstrate the ability to track individual breaking events. This system can be used to measure some spatial and temporal characteristics of breaking waves, such as frequency of breaking, lifetime, velocity, and spatial distributions.

Save