Synthetic aperture matched field approach to acoustic source localization in a shallow-water environment
Keywords:Acoustic arrays, Acoustic fields, Approximation theory, Hydrophones, Signal to noise ratio, Time series analysis, Fourier analysis, Synthetic aperture matched-field method
AbstractMatched field processing is a developing technique for localizing underwater acoustic sources and inverting measured acoustic fields for ocean waveguide properties. Considerable successes have been reported using this technique in deep water and, in the recent past, the technique has shown promise for localizing acoustic sources in shallow water. This paper describes an experiment conducted in the shallow water of the Western Bank near Sable Island on the eastern Canadian continental shelf. The experiment involved examining the localization performance of a small vertical array consisting of only four hydrophones and spanning approximately one-third of the water column against a relatively low signal-to-noise ratio source in a weakly range-dependent environment. In this experiment, the source emitted a series of low-frequency tones that were detectable by Fourier analysis of the received time-series. By estimating the phase of the received signal as a function of time, it was possible to estimate the relative change in the target range during an interval. Using a modified Bartlett matched field processor, the phase information was incorporated to estimate the true target range and depth during the same interval. The results of this experiment indicate that matched field localization can be dramatically improved by incorporating auxiliary information, such as the estimated signal phase history. In this case, the performance of the vertical receiving array approximates the expected performance of a planar array with the same vertical dimension as the actual receiver and a horizontal dimension controlled by the duration of the interval during which the phase history is estimated.
How to Cite
Copyright on articles is held by the author(s). The corresponding author has the right to grant on behalf of all authors and does grant on behalf of all authors, a worldwide exclusive licence (or non-exclusive license for government employees) to the Publishers and its licensees in perpetuity, in all forms, formats and media (whether known now or created in the future)
i) to publish, reproduce, distribute, display and store the Contribution;
ii) to translate the Contribution into other languages, create adaptations, reprints, include within collections and create summaries, extracts and/or, abstracts of the Contribution;
iii) to exploit all subsidiary rights in the Contribution,
iv) to provide the inclusion of electronic links from the Contribution to third party material where-ever it may be located;
v) to licence any third party to do any or all of the above.