An analytical model of spatial correlation between vector fields of surface generated noise in a stratified ocean

Abstract

Traditionally, hydrophone-based acoustic pressure information has been utilized for underwater detection, but the advent of vector sensors has enabled the utilization of particle velocity of sound waves. A vector sensor adds three-axis particle velocity vector components to the conventional acoustic pressure sensor, representing spatial correlation not as a scalar function but as a matrix of four vector components. While analytical solutions exist for vector sensor spatial correlation in the case of simple isotropic noise, such noise fails to reflect the medium properties of the ocean, such as sound speed or density. Previous investigation reflecting the ocean environment derived a pressure spatial correlation model for surface generated noise in a stratified ocean, but this model is limited in the applicability to vector sensors. In this work, we extend the pressure spatial correlation model to vector fields, and by comparing with isotropic noise, we have confirmed that ocean environmental factors significantly influence the spatial correlation of vector sensors.