Passive Acoustic Array Harbor Security Applications

Abstract

Harbor security and protection of maritime assets are issues of increasing concern. Outstanding research questions exist in terms of the optimal protection methodology needed for the wide variety of surface and submerged threats and diverse geographical locations. Economic costs and environmental concerns are also significant overriding issues. Acoustic methods have the advantage of being amenable to tracking and detecting targets both above and below the ocean surface. Moreover, passive acoustic methods are nonintrusive and capable of covering extensive ranges. Acoustic arrays offer significant advantages in terms of gain and signal processing capabilities over discrete, single hydrophones. We investigate the use of horizontal and vertical arrays for the detection and tracking of a remote environment monitoring system (REMUS) autonomous underwater vehicle as well as open-circuit divers in a noisy, shallow water environment. Using conventional beamforming techniques, we obtain positive preliminary results for detection and tracking, which highlight the overall merits of an acoustic array implementation.