ASA 126th Meeting Denver 1993 October 4-8

4pUW7. Noise cancellation, environmental focusing, and source localization.

Michael D. Collins

Naval Res. Lab., Washington, DC 20375

The ability to localize an acoustic source in the ocean is often limited by ambient noise and other types of noise. If the nature of the noise is at least partially understood, this limitation can be reduced significantly by including the noise parameters in the space of search parameters. The performance of this approach has been tested in simulations involving a source buried in ambient noise and interference noise due to a source at a known location. Uncertainty in the ocean environment is another limiting factor that can be reduced by expanding the space of search parameters [Collins and Kuperman, J. Acoust. Soc. Am. 90, 1410--1422 (1991)]. By including the source, noise, and environmental parameters in the search space, it is possible to localize an acoustic source buried in noise in an uncertain environment. Special cases of this optimization problem include source localization, tomography, geoacoustic inversion, focalization, and imaging with acoustic daylight [Buckingham et al., J. Acoust. Soc. Am. 91, 2318(A) (1992)].