Computation of Averaged Sound-Propagation Losses and Frequency/Space Coherence Functions in Shallow Waters
An averaged propagation-loss term, which takes the form of a slowly-varying function of range, depth and frequency.
A fluctuation term, which will be assimilated to a random function and will be characterized by its coherence functions in the range, depth and frequency domains.
Assumingthat the wavelength is much smaller and the horizontal range much larger than the water depth, some approximations may be introduced that allow the above functions to be expressed by continuous integrals; these integrals can be solved numerically through a rather simple computer program. The method is illustrated by some applications to a number of realistic cases in order to show the relative influence of the various parameters characterizing the bottom and the sound-velocity profile.
KeywordsPropagation Loss Sound Propagation Coherence Function Source Depth Active Sonar
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