Ultra Electronics USSI, through ERAPSCO and Sonobuoy TechSystems (STS), is the world's leading and largest provider of Anti-Submarine Warfare (ASW) sonobuoy sensors. Through six decades of providing sonobuoy technology to the US Navy and world-wide allies, Ultra Electronics USSI has developed an organic acoustic engineering expertise in the areas of transducer development, acoustic modeling and advanced digital communications and signal processing. These core competencies have allowed Ultra Electronics USSI to provide advanced acoustic solutions to both prime contractors and integration partners filling capability gaps in autonomous underwater vehicle sensors, next generation mine sweeping, coastal water homeland defense and gas and oil exploration.