DocumentCode :
1548970
Title :
Pseudorandom realization of transient acoustic waves scattered from randomly rough patches
Author :
Ricks, David C.
Author_Institution :
Sci. Applications Int. Corp., McLean, VA, USA
Volume :
22
Issue :
2
fYear :
1997
fDate :
4/1/1997 12:00:00 AM
Firstpage :
332
Lastpage :
341
Abstract :
A simple numerical technique is developed for generating pseudorandom realizations of three-dimensional (3-D) transient acoustic waves that are scattered from two-dimensional (2-D) patches of randomly rough surfaces. The rough surface height of a patch is represented numerically in the 2-D horizontal wavenumber plane by choosing a scheme for interpolation between pseudorandom complex coefficients. Using this approach, the realizations of the patches can be generated from experimentally measured roughness power spectra, and phase information is generated in the frequency domain that leads to time spreads in the time domain. The acoustic scattering is modeled here with first-order perturbation theory. The boundary conditions considered here are pressure-release, rigid, and fluid-fluid. Three different spatial windows are considered for defining the patches. In the time domain, the time spreads of the scattered waveforms agree with predictions. In the frequency domain, the phase is seen as a random walk. The solutions developed here can be used with normal mode propagation models or ray propagation models
Keywords :
acoustic wave scattering; frequency-domain analysis; numerical analysis; oceanography; perturbation theory; random processes; reverberation; time-domain analysis; transfer functions; transients; underwater sound; 2D horizontal wavenumber plane; 2D patches; 3D transient acoustic waves; acoustic scattering; boundary conditions; first-order perturbation theory; frequency domain; interpolation; normal mode propagation models; phase information; pseudorandom complex coefficients; pseudorandom realization; random walk; randomly rough patches; ray propagation models; rough surface height; roughness power spectra; sandy seafloor; scattered waveforms; spatial windows; time domain; time spreads; transient acoustic waves; Acoustic measurements; Acoustic scattering; Acoustic waves; Frequency domain analysis; Interpolation; Power generation; Rough surfaces; Surface acoustic waves; Surface roughness; Two dimensional displays;
fLanguage :
English
Journal_Title :
Oceanic Engineering, IEEE Journal of
Publisher :
ieee
ISSN :
0364-9059
Type :
jour
DOI :
10.1109/48.585952
Filename :
585952
Link To Document :
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