The acoustic landscape during the New England Seamount Experiment observed by the Acoustic Telescope using Adaptive Beamforming

The 3-D Acoustic Telescope (AT) developed by the Woods Hole Oceanographic Institution is a deployable acoustic array with 25 sensors distributed over 10-m disc aperture. An onboard multichannel digital recorder has a sampling rate of 24 kHz, with a -3-dB high-pass filter at 10 Hz and a dynamic range of ∼120 dB. Recently, the AT was successfully deployed during the New England Seamount Experiment (NESMA) field program. The AT aperture has an irregular distribution of sensors, which leads to problems for determining the presence of a low level signal at a bearing compared to sidelobes resulting from such a distribution challenging. ABF mitigates this by generating a beam response pattern based upon the ambient environment using the sample covariance matrix. The AT can then produce a much “cleaner” estimate of the acoustic environment as the data evolve over the observation interval. The presentation will discuss examples derived from the NESMA data taken over its deployment near the New England Seamounts from its deployment in June 2024 to recovery in October 2024. Work supported by the WM Keck Foundation and Code 321 (Ocean Acoustics) of the Office of Naval Research.