Acoustic research in the Hudson River Estuary at the Stevens Maritime Security Laboratory

Stevens Institute of Technology has established a Maritime Security Laboratory (MSL) as a national laboratory resource for government, industry, and universities to advance technologies for the protection of USN maritime infrastructure. Experiment instrumentation includes research vessels, a multiplicity of hydrophones and emitters, stand alone acoustic buoys, diver acoustic simulators, unmanned underwater vehicles (UUVs), and precision instrumentation placement capabilities. The in-river experiments are controlled remotely from a Visualization Center on campus. Acoustic research is supported by sound speed profile measurements, integrated video and acoustic tracking of surface events, and global positionlng system tracking of live divers. Recent results include determination of parameters defining the detection distance of a threat: source level, transmission loss, and ambient noise. The combination of acoustic noise with video data for different kinds of ships in the Hudson River enables estimation of sound attenuation in a wide frequency band. The establishment of a library of various estuarine signatures, including divers, boats, ships, UUVs, construction equipment, and so forth, is underway. This knowledge can be used in a variety of intruder detection scenarios and for optimal methods of threat detection. [This work was supported by ONR Project N00014-05-1-0632: Navy Force Protection Technology Assessment Project.]