Special Topical Issue on Shallow-Water Acoustics; Guest Editors: E. C. Shang and Chi-Fang ChenNo Access

FORWARD AND BACKWARD MODAL STATISTICS FOR ROUGH SEABED SURFACE SCATTERING IN SHALLOW WATER

D. P. KNOBLES

Applied Research Laboratories, University of Texas at Austin, Austin, Texas 78713-8029, USA

Corresponding author.

Search for more papers by this author

and

J. D. SAGERS

Applied Research Laboratories, University of Texas at Austin, Austin, Texas 78713-8029, USA

Search for more papers by this author

https://doi.org/10.1142/S0218396X14400049Cited by:2 (Source: Crossref)

Abstract

Addressed is the physics of sound propagation through a shallow water waveguide whose seabed has a random rough surface. The basic coupled integral equations for the modal amplitudes can be split into forward and backward going coupled integral equations. Numerical solutions of the coupled equations are obtained for multiple roughness realizations from which ensemble averages can be obtained for the modal intensities and cross-mode coherence as a function of range. Sample calculations illustrate some of the basic characteristics of the average cross-mode coherence and intensity with and without seabed attenuation and for different source depths on range scales of 1500 acoustic wavelengths.

Keywords:

References

L. B. Dozier and F. D. Tappert, J. Acoust. Soc. Am. 63, 353 (1978), DOI: 10.1121/1.381746. Web of Science, Google Scholar
J. A. Colosi and A. K. Morozov, J. Acoust. Soc. Am. 126, 1026 (2009), DOI: 10.1121/1.3158818. Web of Science, Google Scholar
D. B. Creamer, J. Acoust. Soc. Am. 99, 2825 (1996), DOI: 10.1121/1.414817. Web of Science, Google Scholar
J. A. Fawcett, J. Acoust. Soc. Am. 92, 290 (1992), DOI: 10.1121/1.404293. Web of Science, Google Scholar
S. R. Rutherford, An examination of coupled mode theory as applied to underwear sound propagation, PhD thesis, University of Texas at Austin (1979) . Google Scholar
R. A. Koch, Coupled mode formalism in three dimensions, ARL-TL-EV-10-01 (2010) . Google Scholar
J. D. Sagers, Predicting acoustic intensity fluctuations induced by nonlinear internal waves in a shallow water waveguide, PhD thesis, University of Texas at Austin (2012) . Google Scholar
O. A. Godin, J. Acoust. Soc. Am. 103, 159 (1998), DOI: 10.1121/1.421085. Web of Science, Google Scholar
D. P. Knobles and J. D. Sagers, J. Acoust. Soc. Am. 130, 2673 (2011), DOI: 10.1121/1.3640845. Web of Science, Google Scholar
D. P. Knobleset al., J. Acoust. Soc. Am. 124, EL151 (2008). Web of Science, Google Scholar
K. L. Williamset al., IEEE J. Ocean. Eng. 27, 376 (2002), DOI: 10.1109/JOE.2002.1040925. Web of Science, Google Scholar
T. Udagawa and B. T. Kim, Phys. Rev. C 40, 2271 (1989), DOI: 10.1103/PhysRevC.40.2271. Web of Science, Google Scholar
D. P. Knobleset al., J. Comp. Acoust. 9, 149 (2001), DOI: 10.1142/S0218396X01000449. Link, Web of Science, Google Scholar