Parametric Sonar to Enhance Torpedo Performance

Navies of the world have recognized the issues of conducting Anti-Submarine Warfare (ASW) in littoral regions since the Falkland Island war (1982). Since that time, the U.S. Navy has aggressively pursued efforts to achieve dominance in the littorals in time of war. Ongoing R&D efforts for torpedos have concentrated on reducing vehicle self-noise, improved tactics, guidance, and control, and improved active and passive sonar. Parametric sonar has never been employed on a torpedo. Advances in array manufacture and supporting electronics now make a multi-modal torpedo sonar that includes a parametric mode realizable. Proposed is an effort to determine how to employ a parametric mode in torpedo sonar using existing torpedo transduction, and determining what changes could be made to baseline arrays to improve the parametric performance. Our approach develops a proof-of-concept for narrow beam parametric sonar that can be used in conjunction with the existing linear sonar systems onboard the torpedo. Because of the unique capabilities that are characteristic of parametric sonar, the steerable parametric beam that we will develop will significantly reduce reverberation, operate in the high noise littoral environment, and improve the ability of the torpedo tactical processor to make correct decisions while seeking a target.