On the width of a ray

Irina I. Rypina, Michael G Brown

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

Consistent with earlier work by Kravtsov and Orlov, a simple general expression for the width of a Fresnel zone δrF in a smooth inhomogeneous environment is derived; this is the diffractive contribution to the width of a ray. In a stratified environment at long range, the general Fresnel zone width expression is shown to reduce approximately to one that is proportional to √|α|r(R-r)/σ where α is the ray stability parameter, σ is the acoustic frequency, r is the range from the source to the field point of interest, and R is the source to receiver range. In a stratified environment on which a weak small-scale perturbation is superimposed, deterministic rays in the background environment that connect fixed end points break up into bundles of micromultipaths at moderate to long range and a second, scattering-induced, contribution δrs to the width of a ray must be considered. It is shown that δrs is proportional to |α|r(R-r) and argued that in a micromultipathing environment the total effective width of a background ray is δr tot = √δrF 2 + δr s 2. Theoretical predictions are shown to agree well with travel-time sensitivity kernel calculations.

Original languageEnglish (US)
Pages (from-to)1440-1448
Number of pages9
JournalJournal of the Acoustical Society of America
Volume122
Issue number3
DOIs
StatePublished - 2007

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rays
acoustic frequencies
travel
bundles
receivers
Ray
perturbation
sensitivity
predictions
scattering

ASJC Scopus subject areas

  • Acoustics and Ultrasonics

Cite this

On the width of a ray. / Rypina, Irina I.; Brown, Michael G.

In: Journal of the Acoustical Society of America, Vol. 122, No. 3, 2007, p. 1440-1448.

Research output: Contribution to journalArticle

Rypina, Irina I. ; Brown, Michael G. / On the width of a ray. In: Journal of the Acoustical Society of America. 2007 ; Vol. 122, No. 3. pp. 1440-1448.
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