88. leveraging the ocean's ambient soundscape to localize subsea drifters
Name: Perry W Naughton
Grad Year: 2018
The localization of sensors and vehicles in underwater environments remains a difficult problem. GPS and other technology that relies on electromagnetic signals does not work over distances larger than a few meters. Acoustic methods can be power intensive, sensitive to the ambient noise field and can disturb the environment. This work investigates the use of ambient acoustic noise to estimate the relative positions of mobile, underwater drifters. Our proposed method does not require introducing an active source, overcoming many of the limitations of current acoustic methods. Instead the proposed method relies on the abundant acoustic energy in underwater environments. To achieve our localization goal, we first show how to extract coherent information from the complex and often incoherent ocean soundscape. We do this on both erratic, impulsive noise and low frequency noise where we cannot identify the source. Using this coherent information, we show how to estimate the relative geometry of each drifter in the array.