Integrated Sensor System for Load and Condition Assessment

New results on false alarm characteristics from our research show that an estimate of a contact's effective target strength could be used as a very reliable classifier for near specular submarine detections. Exploiting this would require that theprocessing system be able to adaptively estimate transmission loss from source or receiver to an arbitrary position prior to classification. Initial indications are that an accuracy of ¿ 10 dB in transmission loss would be more than adequate to classifyeven the smallest of submarines. Since accuracy better than this has been achieved in the past, we believe this approach has a good possibility of succeeding with an integrated network of sensors.The proposed classification concept is that the sonobuoys would collect unclipped direct arrival information using attenuated hydrophones. This information, along with other information characterizing potential contacts, would be transmitted to theaircraft at a low data rate. An aircraft based processor would then assemble all the data from the sonobuoy network, adaptively compute a global transmission loss model for the area, and classify contacts based on their consistency with the target strengthmodel.