Basin scale coherence of Kauai-Beacon m-sequence transmissions received at Wake Island and Monterey, CA

The 75 Hz Kauai-Beacon source is well-situated for observing the North Pacific Ocean acoustically, and ongoing efforts enable transmissions and analysis of broadband signals in 2023 and beyond. This is the first demonstration of acoustic receiving along paths to Wake Island (∼3500 km) and Monterey Bay (∼4000 km). The 44 received m-sequence waveforms exhibit excellent phase stability with processing gain approaching the maximum theoretical gain evaluated over the 20 min signal transmission duration. The article concludes with a discussion on the future source utility and highlights research topics of interest, including observed Doppler (waveform dilation), thermometry, and tomography.