Precise geolocation of deployed sonobuoys is a standing requirement of the U.S. Navy for improving ASW operations. Current approaches to sonobuoy localization often require close over-flight of the sonobuoy by the monitoring aircraft. This compromises the security of the aircraft, and does not provide a precision result. There is a obvious need for a Sonobuoy Geolocation System that has the following characteristics: 1) ability to operate at significant (50 - 100 mile) standoff distances, 2) geolocation of multiple sonobuoys simultaneously, 3) precise location to within 100 meters, 4) low cost @ $50.00 per sonobuoy in production, 5) low probability of intercept and detection, and 6) not susceptible to narrowband jamming. Under Phase I of this effort, ASIT will refine its preliminary system design, for precision geolocation of sonobuoys, at an extremely low cost per system. The novel solution that is proposed specifically does not incorporate Global Positioning System (GPS) receivers on each sonobuoy, but does take advantage of Direct Sequence Spread Spectrum (DSSS) signals to determine precise range and geolocation. The use of low-cost commercial wireless technology is key to the success of the program. During this effort, ASIT proposes to make the design a reality by building a prototype sonobuoy geolocation system that will be ready for demonstration to the customer by the end of the Phase I effort.
Benefits: To address both Government and commercial needs for low-cost, robust, precision geolocation, this effort will use spread spectrum signal processing technology combined with exisiting commercial wireless components to provide a reliable geographic position locator.
Keywords: Direct Sequence Spread Spectrum, Sonobuoy, Anti-Submarine Warfare, Geolocation, Direction Finding, Wireless, Transponder, Ambiguity Function
