Effect of Sub-Bottom Inhomogenieties on Shallow Water Spatial Coherence

  • S. T. McDaniel
  • D. F. McCammon
Part of the NATO Conference Series book series (NATOCS, volume 16)

Abstract

A coupled-mode approach is applied to examine the spatial coherence of the acoustic field in an inhomogeneous waveguide. The formulation derived is a matrix analog of the equations resulting from application of strong fluctuation theory to propagation in an inhomogeneous medium. The expression that results is evaluated to determine the effect of sub-bottom roughness on horizontal spatial coherence in shallow water. Results are presented for low-frequency propagation in an environment in which a homogeneous clay-silt sediment overlies irregular bedrock. Numerical examples demonstrate the effects of frequency, water depth and source-receiver geometry on coherence. For the cases examined, the field is coherent over many wavelengths in qualitative agreement with existing data.

Keywords

Coherence Explosive Acoustics Hydrophone 

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References

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Copyright information

© Plenum Press, New York 1986

Authors and Affiliations

  • S. T. McDaniel
    • 1
  • D. F. McCammon
    • 1
  1. 1.Applied Research LaboratoryThe Pennsylvania State UniversityState CollegeUSA

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