In-Air Sound Sources for Anti-Submarine Warfare

With the continual reduction in radiated acoustic levels of submarines around the world, active sonar has become essential in all aspects of Anti-Submarine Warfare (ASW) operations. Further, bistatic and multistatic active sonar systems increase the spatial diversity of detection systems and afford improvements over monostatic systems in performance against potential threat submarines. Source development has been a focus, but the size and complexity of source designs, particularly at the lower frequencies necessary for longer range acoustic propagation, makes this aspect of the active sonar system technically challenging. This is especially true for air-deployable multistatic active sonar systems. An airborne acoustic source, combined with a field of air-deployed acoustic sensors in the water, has the potential to enable a wide area, active, search capability that limits the ability of submerged threats to effectively predict source location and reduce their own vulnerability to detection. The purpose of this SBIR proposal is to: Assess the feasibility of airborne acoustic sources for active sonar Develop source concepts that provide the ensonification levels and source waveforms necessary for submerged threat detection, and Plan at-sea experiments to validate the concepts for development.