Title :
Time-frequency representations for wideband acoustic signals in shallow water
Author :
Chen, Chuen-Song ; Miller, James H. ; Bourdreaux-Bartels, G.F. ; Potty, Gopu R. ; Lazauski, Colin J.
Author_Institution :
Rhode Island Univ., Narragansett, RI, USA
Abstract :
Wideband acoustic propagation in shallow water has a unique arrival structure due to modal group speed dispersion. It is possible to unravel the modal dispersion characteristics using a proper time-frequency (TF) analysis. During the Asian Seas International Acoustics Experiment (ASIAEX) - East China Sea (ECS) experiment, signal collected by the vertical arrays have been processed using several time-frequency analysis techniques. Based upon the dispersion characteristics of acoustic propagation, theoretical time-frequency structure is used to determine the change of group delay. We present an improved time-frequency representation to provide higher resolution for TF diagrams using ECS data. The dispersion characteristics of ECS data are observed with good resolution; this aids in increasing the performance of the inversion technique for long range sediment tomography.
Keywords :
acoustic signal processing; acoustic tomography; acoustic wave velocity; oceanography; time-frequency analysis; underwater acoustic propagation; ASIAEX; Asian seas international acoustics experiment; East China Sea experiment; group delay; inversion technique; modal dispersion characteristics; modal group speed dispersion; sediment tomography; time-frequency analysis; wideband acoustic propagation; wideband acoustic signals; Acoustic propagation; Data mining; Dispersion; Fourier transforms; Matching pursuit algorithms; Propagation delay; Signal processing; Signal resolution; Time frequency analysis; Wideband;
Conference_Titel :
OCEANS 2003. Proceedings
Conference_Location :
San Diego, CA, USA
Print_ISBN :
0-933957-30-0
DOI :
10.1109/OCEANS.2003.178368
