Acoustic field coherence in four-dimensionally variable shallow water environments : estimation using co-located horizontal and vertical line arrays
Citable URI
https://hdl.handle.net/1912/6549Abstract
The implementation of two- and three-dimensional acoustic receiver arrays is
challenging in the ocean environment. Fixed geometry and connectivity can only be built
and maintained at great expense. However, such ideal arrays can be very powerful for
signal detection, classification, and tracking, although many of the signal-processing
methods employed are subject to constraints of acoustic field temporal and spatial
coherence. Thus, understanding the processes at work determining coherence is essential
because system effectiveness may then be predictable from environmental parameter
input. To study acoustic fields and coherence over finite aperture, the research
community has recently taken steps to enable routine use of co-located horizontal and
vertical line arrays, typically arranged in the shape of the Roman letter L (or Greek ),
with the horizontal leg on the seafloor. This is a small subset of all possible geometries,
but it enables measurements of acoustic field coherence not possible with single line
arrays. Here, new L-array measurements made in the SW06 field program are used to
measure coherence and test coherence predictions via joint analysis of vertical and
horizontal line array receptions. Impulsive mode arrivals (including mode multipath)
from fixed sources will be estimated using the vertical array. Signals on the horizontal
array, which is neither broadside nor endfire, will be compared with signals synthesized
using the mode arrivals to estimate azimuthal decorrelation effects. Results can be
compared with coherence estimates from computational and theoretical studies.
Description
Underwater Acoustic Measurements (UAM) 2nd International Conference & Exhibition on "Underwater Acoustic Measurements: Technologies & Results," 25-29 June 2007, Heraklion, Crete, Greece.
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Suggested Citation
Proceedings of the 2nd International Conference and Exhibition on "Underwater Acoustic Measurements: Technologies & Results" (2007), :65-7206Related items
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