Signal Processing and System Concepts to Exploit Passive Signals in Airborne Active ASW Missions

Period of Performance: 04/06/1999 - 04/06/2001


Phase 2 SBIR

Recipient Firm

RDA Inc.
P.O. Box 49 Array
Doylestown, PA 18901
Principal Investigator


Future Airborne ASW tactics will depend heavily upon the use of active sonar and bistatics with a distributed field of sonobuoys as the primary means of initial target detection and localization. However, the bistatic detection and classification problem is compounded by short contract times, evasive target maneuvers, and the ambiguous nature of target echoes and clutter. Recent studies indicate that some target signals are potentially exploitable by passive detection, even in the acoustic and tactical environments of interest for active search. A method of detecting these signals, and a method of integrating the clues provided by such detection, is needed to augment the information obtained from the processing of the active sonar data. During the Phase I contract, a system level approach was developed to achieve the passive signal detection and to integrate the capability into an Air ASW active search mission. The proposed techniques were modeled and used with real data to demonstrate that the passive detection methods worked and how the resulting detection data could be used in active search Air ASW missions. The Phase II effort will concentrate on a larger set of data in order to validate the design and assess performance. The design will be expanded to include capability for the next generation of sonobuoy, and a prototype will be developed to process data in real time. Finally, the real time prototype will be integrated with an operator display and used with real data to demonstrate how the passive processing augments the active search system.