Toward distributed noise-source localization for underwater sensor networks

Underwater sensor network nodes typically detect and communicate through the propagation of acoustic waves. To localize an unknown noise-source with an underwater sensor network, one can combine bearing estimates from various sensors while taking into account their respective position. As the battery life of each underwater sensor dictates the overall network endurance, each sensor must make sense of the various propagated signals and derive a likely bearing estimate to pass to neighbouring nodes while consuming as little power as possible. Most publications presenting distributed noise-source localization approaches performed by underwater sensor networks are inadequate in that their assumptions do not usually apply to an underwater setting and only use simulated scenarios. Unlike these publications, the proposed distributed noise-source localization scheme is tailored to and tested with real underwater acoustic detections. In particular, we present simple computational schemes for the sake of extending the operational life of the overall network. Those schemes monitor and estimate the main bearing characteristics while simplifying their representation. In general, the proposed techniques outperform the traditional approach of selecting bearings based on an intensity-only threshold.