A Method of Measuring the In Situ Seafloor Sound Speed using Two Receivers with Warping Transformation

We present a method of measuring the in situ superficial seafloor sound speed by using two receivers deployed vertically in sediment, based on the dispersion characteristic of normal modes in shallow water. Warping transformation is adopted to extract the first normal mode from the broadband propagation signals. Some experimental results which could validate the method are shown. One of the advantages of the method is that the seafloor sound speed can be solved directly from the relative vertical transmission loss of the first normal mode without the exact priori information of the environmental parameters such as the sound speed profile, the water-column depth and the source location.

[1]  Zhang Renhe,et al.  A Broadband Geoacoustic Inversion Scheme , 2004 .

[2]  L. Frazer,et al.  Acoustic lance: New in situ seafloor velocity profiles , 1996 .

[3]  Barbara Nicolas,et al.  Estimation of modal group velocities with a single receiver for geoacoustic inversion in shallow water. , 2010, The Journal of the Acoustical Society of America.

[4]  C. Mccann,et al.  An attenuation-based sediment classification technique using Chirp sub-bottom profiler data and laboratory acoustic analysis , 2002 .

[5]  Kevin L. Williams,et al.  Direct measurement of sediment sound speed in Shallow Water '06. , 2008, The Journal of the Acoustical Society of America.

[6]  A. Best,et al.  Comparison of in situ and laboratory acoustic measurements on Lough Hyne marine sediments , 2001 .

[7]  Li Feng-hua,et al.  Geoacoustic Inversion Based on a Vector Hydrophone Array , 2007 .

[8]  Zhang Renhe,et al.  Geoacoustic Inversion Based on Dispersion Characteristic of Normal Modes in Shallow Water , 2007 .

[9]  Jean-Louis Lacoume,et al.  Matched Representations and Filters for Guided Waves , 2009, IEEE Transactions on Signal Processing.

[10]  P. White,et al.  Measurement of the In Situ Compressional Wave Properties of Marine Sediments , 2007, IEEE Journal of Oceanic Engineering.

[11]  N. Chapman,et al.  Geoacoustic inversion in a dispersive waveguide using warping operators. , 2011, The Journal of the Acoustical Society of America.

[12]  E. Hamilton Sound velocity and related properties of marine sediments, North Pacific , 1970 .