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Title: Underwater acoustic sensing using the geometric phase
We present a sensing modality using the geometric phase of acoustic waves propagating in an underwater environment. We experimentally investigate the effect of scattering by a small subwavelength perturbation on a flat submerged surface. We represent the state of an acoustic field in the unperturbed and perturbed cases as multidimensional vectors. The change in geometric phase is obtained by calculating the angle between those vectors. This angle represents a rotation of the state vector of the wave due to scattering by the perturbation. We perform statistical analysis to define a signal-to-noise ratio to quantify the sensitivity of the geometric phase measurement and compare it to magnitude based measurements. This geometric phase sensing modality is shown to have higher sensitivity than the magnitude based sensing approach.  more » « less
Award ID(s):
2242925
PAR ID:
10520118
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
AIP
Date Published:
Journal Name:
The Journal of the Acoustical Society of America
Volume:
154
Issue:
5
ISSN:
0001-4966
Page Range / eLocation ID:
2869 to 2877
Format(s):
Medium: X Other: pdf
Sponsoring Org:
National Science Foundation
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