Understanding and Utilizing Waveguide Invariant Range-frequency Striations in Ocean Acoustic Waveguides

Abstract : The range-frequency waveguide invariant describes striations that often appear in plots of acoustic intensity versus range and frequency. Signal processing techniques based on the waveguide invariant are able to exploit the effects of the ocean acoustic waveguide without requiring detailed knowledge of the sound speed profile or of the seafloor. This thesis develops a framework for understanding and calculating the waveguide invariant, and uses that framework to create signal processing techniques for the waveguide invariant which may be applicable to passive and active sonar, time-reversal mirrors, and array processing. A method for passively estimating the range from an acoustic source to a receiver is developed, and tested on experimental data. Heuristics are developed to estimate the minimum source bandwidth and minimum horizontal aperture required for range estimation. A semi-analytic formula for the waveguide invariant is derived using WKB approximation along with a normal mode description of the acoustic field in a range-independent waveguide. This formula illustrates how the SSP and the seafloor properties affect the value of the waveguide invariant. Array processing techniques designed specifically for the purpose of observing range-frequency striations are developed and demonstrated. Finally, a relationship between the waveguide invariant and wavenumber integration is derived.

[1]  De Lillo,et al.  Advanced calculus with applications , 1982 .

[2]  Arthur B. Baggeroer,et al.  Estimation of the Distribution of the Interference Invariant with Seismic Streamers , 2002 .

[3]  James F. Lynch,et al.  Perturbative inversion methods for obtaining bottom geoacoustic parameters in shallow water , 1987 .

[4]  M. Glas,et al.  Principles of Computerized Tomographic Imaging , 2000 .

[5]  J. S. Wood,et al.  Theory of acoustic field invariants in layered waveguides , 1993 .

[6]  W. Kuperman,et al.  Matched field processing: source localization in correlated noise as an optimum parameter estimation problem , 1988 .

[7]  H C Song,et al.  Adaptive time-reversal mirror. , 2001, The Journal of the Acoustical Society of America.

[8]  Michael D. Serotta,et al.  Acoustics of layered media II , 1990 .

[9]  P. Ratilal,et al.  Empirical dependence of acoustic transmission scintillation statistics on bandwidth, frequency, and range in New Jersey continental shelf. , 2009, The Journal of the Acoustical Society of America.

[10]  Colin H. Hansen,et al.  Techniques for extraction of the waveguide invariant from interference patterns in spectrograms , 2006 .

[11]  W. Kuperman,et al.  A long-range and variable focus phase-conjugation experiment in shallow water , 1999 .

[12]  Hailiang Tao,et al.  Single Hydrophone Passive Localization of Transiting Acoustic Sources , 2007, OCEANS 2007 - Europe.

[13]  William S. Hodgkiss,et al.  A time-reversal mirror with variable range focusing , 1998 .

[14]  D. Sternlicht,et al.  Active rapid geoacoustic characterization using a seismic survey source , 2004, IEEE Journal of Oceanic Engineering.

[15]  A. V. Ogurtsov,et al.  The effect of hydrodynamic variability on frequency shifts of the interference pattern of a sound field in a shallow sea , 1998 .

[16]  J. Roebuck,et al.  Waves in layered media , 1981 .

[17]  D. Rouseff.  Effect of shallow water internal waves on ocean acoustic striation patterns , 2001 .

[18]  J.J. Murray,et al.  Matchless field processing in shallow water , 2000, OCEANS 2000 MTS/IEEE Conference and Exhibition. Conference Proceedings (Cat. No.00CH37158).

[19]  D. Rouseff,et al.  Internal waves as a proposed mechanism for increasing ambient noise in an increasingly acidic ocean. , 2010, The Journal of the Acoustical Society of America.

[20]  Introduction to Fourier Transforms for Image Processing Basis Functions , .

[21]  W. Kuperman,et al.  Robust time reversal focusing in the ocean. , 2003, The Journal of the Acoustical Society of America.

[22]  Temporal coherence after multiple forward scattering through random three-dimensional inhomogeneities in an ocean waveguide. , 2008, The Journal of the Acoustical Society of America.

[23]  A. W. M. van den Enden,et al.  Discrete Time Signal Processing , 1989 .

[24]  M. F.,et al.  Bibliography , 1985, Experimental Gerontology.

[25]  D. Rouseff,et al.  Broadband source localization using horizontal-beam acoustic intensity striations. , 2010, The Journal of the Acoustical Society of America.

[26]  Michael B. Porter,et al.  Computational Ocean Acoustics , 1994 .

[27]  T. Akal,et al.  Group and Phase Speed Analysis for Predicting and Mitigating the Effects of Fluctuations , 2002 .

[28]  Chensong He,et al.  Enhanced Kalman Filter Algorithm Using the Invariance Principle , 2009, IEEE Journal of Oceanic Engineering.

[29]  Sunwoong Lee,et al.  The array invariant. , 2006, The Journal of the Acoustical Society of America.

[30]  K. Stafford,et al.  Long-range acoustic detection and localization of blue whale calls in the northeast Pacific Ocean. , 1998, The Journal of the Acoustical Society of America.

[31]  K. Heaney.  Rapid geoacoustic characterization: applied to range-dependent environments , 2004, IEEE Journal of Oceanic Engineering.

[32]  M. Brown,et al.  Rays, modes, wavefield structure, and wavefield stability , 2003, nlin/0312049.

[33]  A. Thode.  Source ranging with minimal environmental information using a virtual receiver and waveguide invariant theory. , 2000, The Journal of the Acoustical Society of America.

[34]  K. Heaney,et al.  Rapid geoacoustic characterization using a surface ship of opportunity , 2004, IEEE Journal of Oceanic Engineering.

[35]  Henrik Schmidt,et al.  Robust passive range estimation using the waveguide invariant. , 2010, The Journal of the Acoustical Society of America.

[36]  D. Rouseff,et al.  Demonstration of the invariance principle for active sonar. , 2008, The Journal of the Acoustical Society of America.

[37]  Robert C. Spindel,et al.  A test of basin-scale acoustic thermometry using a large-aperture vertical array at 3250-km range in the eastern North Pacific Ocean , 1999 .

[38]  William L. Briggs,et al.  The DFT : An Owner's Manual for the Discrete Fourier Transform , 1987 .

[39]  Liang An,et al.  Calculating the waveguide invariant by passive sonar lofargram image , 2007, 2007 14th International Conference on Mechatronics and Machine Vision in Practice.

[40]  Robert C. Spindel,et al.  Modeling the Waveguide Invariant as a Distribution , 2002 .

[41]  V. Petnikov,et al.  Shallow Water Acoustics , 2002 .

[42]  Underwater acoustic beam dynamics. , 2009, The Journal of the Acoustical Society of America.

[43]  Kuperman,et al.  Localization using Bartlett matched-field processor sidelobes , 2000, The Journal of the Acoustical Society of America.

[44]  W. Kuperman,et al.  Application of waveguide invariants to analysis of spectrograms from shallow water environments that vary in range and azimuth , 1999 .

[45]  F. R. DiNapoli,et al.  Numerical Models of Underwater Acoustic Propagation , 1979 .

[46]  T. C. Yang.  Beam intensity striations and applications. , 2002, The Journal of the Acoustical Society of America.

[47]  Hailiang Tao,et al.  Waveguide invariant focusing for broadband beamforming in an oceanic waveguide. , 2008, The Journal of the Acoustical Society of America.

[48]  M. Taroudakis.  Ocean Acoustic Tomography , 2006 .

[49]  Nicholas C. Makris,et al.  Mean and variance of the forward field propagated through three-dimensional random internal waves in a continental-shelf waveguide , 2005 .

[50]  V. M. Kuzkin.  Spectral intensity oscillations of a sound field in a randomly inhomogeneous ocean , 2000 .

[51]  L. Auger.  The Journal of the Acoustical Society of America , 1949 .

[52]  J. Krolik,et al.  Waveguide invariant broadband target detection and reverberation estimation. , 2008, The Journal of the Acoustical Society of America.