Extended towed-array processor by overlapped correlator

Abstract

The development of an algorithm for extended towed-array measurements, which could be used by matched-field estimators to obtain information about depth and range of a source, is studied. This algorithm combines coherently the acoustic signal arrivals at a moving hydrophone towed array by making proper compensation through a phase correction factor for considerable fluctuations in phase, irregularities in the tow path of the physical array, as well as in amplitude during the coherent

integration time. The concept of the extended towed-array processing is based on what we call overlapped correlator, which provides the phase correction factor by correlating overlapping space samples of the acoustic signal received at successive moments in time by the moving towed array.

The algorithm has been applied on numerical data generated by the SNAP normal mode model. The

effects of space and time coherence of the signal and the random and systematic errors on the

extended towed-array measurements are examined and give guidelines for experimental applications

of this algorithm.