title: Measurement of acoustic particle motion in shallow water and its application to geoacoustic inversion.
abstract: Within an underwater acoustic waveguide, the interference among multipath arrivals causes a phase difference in orthogonal components of the particle velocity. When two components of the particle velocity are not in phase, the fluid particles follow an elliptical trajectory. This property of the acoustic field can be readily detected by a vector sensor. A non-dimensional vector quantity, the degree of circularity, is used to quantify how much the trajectory resembles a circle. In this paper, vector sensor measurements collected during the 2013 Target and Reverberation Experiment are used to demonstrate the effect of multipath interference on the degree of circularity. Finally, geoacoustic properties representing the sandy sediment at the experimental site are inverted by minimization of a cost function, which quantifies the deviation between the measured and modeled degree of circularity.
authors.affiliation: Applied Physics Laboratory, University of Washington-Seattle, 1013 NE 40th Street, Seattle, Washington 98105, USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Dall'Osto
authors.affiliation: Department of Marine Sciences and Convergent Technology, Hanyang University, 55 Hanyangdaehak-ro, Sangnok-gu Ansan, Gyeonggi-do 15588, Korea.
authors.forename: Jee Woong
authors.initials: JW
authors.lastname: Choi
authors.affiliation: Applied Physics Laboratory and Mechanical Engineering, University of Washington-Seattle, 1013 NE 40th Street, Seattle, Washington 98105, USA.
authors.forename: Peter H
authors.initials: PH
authors.lastname: Dahl