NPAL Acoustic Noise Field Coherence and Broadband Full Field Processing

Abstract

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Passive ocean acoustic tomography

“…Under such conditions, it is impossible to reconstruct the precise Green's functions from mea sured noise, but it is possible to determine the travel times of rays or normal modes between the considered points [10,12]. Having processed the NPAL Billboard Array Experiment data [13], we demonstrate in our work that the deterministic travel times can be mea sured using mutual correlation of noise with an accu racy sufficient to perform passive acoustic tomogra phy.…”

“…The experiment was carried out by the NPAL [13]. At the same time, extensive noise data were obtained, and P.F.…”

“…In most records, one or a few discrete sources (passing ves sels, sea mammals, or microearthquakes) dominated over the contribution of diffuse noise coming from the distant areas [13].…”