Exact One-way Methods for Acoustic Waveguides
نویسنده
چکیده
Exact one-way re-formulations of the Helmholtz equation are useful for waveg-uide problems, since the resulting equations can be eeciently solved as \initial" value problems by range marching methods. Some numerical methods for these re-formulations are reviewed in this paper. This includes a switched method that avoids the singularities of the operators and the large range step methods that give exact solutions for range independent regions and allow large range steps for weakly range dependent regions. For waveguides with curved bottoms, a method based on a local orthogonal transformation is described. As an interesting application, the scattering problem of periodic waveguides is considered.
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One - way Large Range Step Methods forHelmholtz
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