Strike Group Active Sonar Exploitation

The Anti-Submarine Warfare (ASW) capabilities of surface combatants, often operating in carrier or expeditionary strike groups, rely heavily on active sonar for detection due to the quieting of adversary submarines. These combatants have full knowledge of their own transmissions however; they employ monostatic sonar with communication links and advanced planning in an attempt to avoid mutual interference issues. Sedna and Alion propose an investigation into approaches for a Navy strike group multistatic active processing concept designed to exploit state-of-the-art data exchange, waveform design, and multi-source transmissions. Inherent in this proposal is the use of current continuous waveform transmissions as well as legacy pulsed transmissions. We propose the use of a common time standard within the Strike Group to support a highly accurate multistatic processing scheme. We propose to modify the sonar transmission itself, pulsed or continuous, to provide time of transmission on a periodic basis. Furthermore, we address situations of degraded or non-functional communications.