Research PaperNo Access

Bottom Attenuation Coefficient Inversion Based on the Modal Phase Difference Between Pressure and Vertical Velocity from a Single Vector Sensor

Alexandre L. Guarino

https://orcid.org/0000-0001-8183-3597

Department of Physics, Naval Postgraduate School, Monterey, CA 93943, USA

E-mail Address: alexandre.guarino.br@nps.edu

Corresponding author.

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Kevin B. Smith

Department of Physics, Naval Postgraduate School, Monterey, CA 93943, USA

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, and

Oleg A. Godin

Department of Physics, Naval Postgraduate School, Monterey, CA 93943, USA

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https://doi.org/10.1142/S2591728521500080Cited by:4 (Source: Crossref)

Abstract

An inversion scheme based on time-warping is presented for estimating the attenuation coefficient of a sediment bottom using a single vector sensor, restricted to shallow water and using low-frequency impulsive sources. The attenuation information is extracted from the modal phase difference between pressure and vertical velocity. The method is derived from Pekeris waveguide theoretical equations and the eigen values are obtained using the normal mode model Kraken. Some changes are made to the time-warping process to mitigate the inherent interference between adjacent modes, which improves the phase extraction capabilities. Results are presented for a two-layer, homogeneous environment using the RAM propagation model for depth-dependent sound speed profile simulations. This version of RAM was updated to provide radial and vertical velocities. For additional generality, the technique is evaluated in the presence of white noise.

Keywords:

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