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Mode functions for the wide-angle approximation to the parabolic equation
The Journal of the Acoustical Society of America, 1998The parabolic approximation to the wave equation is examined within the context of normal mode theory. In a layered waveguide, the horizontal propagation constants and modal amplitudes of the field Ψ satisfying the standard parabolic equation (SPE) approximation can be mapped exactly into the amplitudes and wave numbers of the normal modes for the ...
Amy R. Smith, Kevin B. Smith
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On the mode parabolic equation method for the elastic media
2020 Days on Diffraction (DD), 2020In this work we develop an approach to derivation of a system of mode parabolic equations for 3D layered elastic media without assumption of weak elasticity. This approach is based on the generalized multiscale expansions method.
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Parabolic equation modeling of normal mode propagation in a wedge
The Journal of the Acoustical Society of America, 1986The parabolic equation model has been used to investigate the behavior of the “wedge modes” described in the experimental results of Hobaek, Tindle, and Muir [J. Acoust. Soc. Am. Suppl. 1 78, S70 (1985)] for propagation in a shallow water wedge. The wavefronts of wedge modes are not vertical, but are curved into arcs of circles centered on the wedge ...
Finn B. Jensen, C. T. Tindle
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Weak shear modulus in the acoustic mode parabolic equation
2016 Days on Diffraction (DD), 2016By using the multiscale expansions method, we derive an elastic mode parabolic equation. As a small parameter, we choose the ratio of a typical wavelength to a typical size of horizontal inhomo-geneities. The shear modulus is of the order of the small parameter.
Mikhail Yu. Trofimov +2 more
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Wave mode computing method using the step-split Padé parabolic equation
Chinese Physics B, 2022Models based on a parabolic equation (PE) can accurately predict sound propagation problems in range-dependent ocean waveguides. Consequently, this method has developed rapidly in recent years. Compared with normal mode theory, PE focuses on numerical calculation, which is difficult to use in the mode domain analysis of sound propagation, such as the ...
Chuan-Xiu Xu, Guang-Ying Zheng
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The adiabatic mode parabolic equation
The Journal of the Acoustical Society of America, 1993An efficient method is developed for solving problems involving three-dimensional acoustic propagation in a thin spherical shell. The method is based on the adiabatic mode approximation, which assumes that energy coupling between modes is negligible, and the parabolic equation (PE) method, which efficiently handles spatial variations in the acoustic ...
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Curved oversized EM waveguides: adiabatic modes and parabolic equation
International Seminar. Day on Diffraction. Proceedings (IEEE Cat. No.99EX367), 1999Two alternative representations of the wave field in a curved oversized electromagnetic waveguide are discussed: adiabatic modes, matched to the local value of the axis curvature, and full-wave solution of the vectorial parabolic equation. The latter, although being asymptotically equivalent to the adiabatic mode theory, displays additional diffraction
A.V. Popov, null Ning Yan Zhu
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Comparison of parabolic equation and coupled mode solutions to seismo-acoustic problems
The Journal of the Acoustical Society of America, 2011Parabolic equation methods that use the single scattering approximation and improved rotated coordinate methods generate accurate and efficient solutions for range-dependent underwater acoustic problems with elastic sediments. Recently these methods have demonstrated the conversion of acoustic energy in a fluid into shear propagation in an underlying ...
Scott D. Frank +3 more
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Mode equation and its solution for dielectric waveguide with parabolic cross-section
Optical and Quantum Electronics, 1989The mode equation for the dielectric waveguide with parabolic cross-section is derived using both the effective index method and WKB theory, and the expression of the mode propagation constant or effective index is solved directly from this mode equation, so that the mode-propagation properties of this kind of waveguide can be analysed conveniently ...
Chunsheng MA, Shiyong Liu
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Application of the mode vector parabolic equation to the 3-dimensional wedge problem
The Journal of the Acoustical Society of America, 1995The MVPE [Abawi etal., this session] is applied to the problem of propagation of waves in a 3-dimensional coastal wedge and the results are compared with those when horizontal coupling is neglected and with the results obtained from conventional 3-dimensional methods.
Ahmad T. Abawi, W. A. Kuperman
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