ABSTRACT
A general approach to signal and data processing in difficult and varied ocean channels has not been forthcoming. However, research trends are leading to an interactive signal, data and environmental processing formulation, with loose couplings among them. The beamformer, enhanced time delay estimator, contact motion estimator, and acoustic prediction elements are synergistic through cooperative couplings, allowing sharing of the extracted information within each stage. This basic time delay estimator provides the basic measurements of time intervals by processing the observed contact signature. The basic time delay estimator mapping process leads to varying accuracies depending on received contact signature, existing environmental conditions, and the time allowed for observation. The time delay track estimator outputs are fed forward to the contact track estimator, and back to the dynamic window/gate design controller and beamformer. Finally, the contact track estimator performs consistency checks and sensitivity analysis prior to confirming an extracted contact track.
