Experimental Noise Measurement System for Ship Sonar Design Navy STTR FY2015.A Sol No.: Navy STTR FY2015.A Topic No.: N15A-T015 Topic Title: Experimental Noise Measurement System for Ship Sonar Design Proposal No.: N15A-015-0012 Firm: Adaptive Methods, Inc 5860 Trinity Parkway Suite 200 Centreville, Virginia 20120 Contact: Kevin Kieffer Phone: (301) 840-9722 Abstract: Hull mounted sensor arrays are an important tool used to determine localized threat assessment. The location of these arrays on the ship is critical. They must be placed at the quietest location on the hull to minimize own-ship noise which can interfere with array sensitivity. To determine these quiet locations, Adaptive Methods has proposed incorporating vector sensing modules which can be temporarily attached to the outside of the hull at any desired location. These modules will determine noise source location, direction and frequency data. Once post processing of multiple devices at multiple locations is complete, a spectral map of the hull will be created. The Navy will then use this spectral map to determine the best location for the hull mounted sensor arrays. Benefits: Hull mounted sonar systems on ships and submarines are important assets in underwater sensing for anti-submarine warfare (ASW) and torpedo defense. While underway, vibrations in the vessel's hull and radiated noise from the vessel both provide an undesired "self-noise" that can interfere with the operation of hull mounted sensors. Because of a wide distribution of power plants in the hull, machinery driven noise can vary significantly from one part of the hull to another, and can also vary depending on ships speed and what machinery is currently in operation. Passage of the hull through the sea, depending on sea-state, can also generate hull vibrations. Clearly, finding the best location for a hull mounted acoustic sensor can minimize noise interference to that sensor. A means to "map out" the acoustic and vibration field on and around the vessel's hull while underway is required to determine the best location for a hull-mounted sensor. Return