Geoacoustic inversion and source localization from multisource broadband HLA data

Abstract

In underwater acoustics research, source localization efforts are often hampered by incorrect environmental information, and geoacoustic inversion results can be limited by errors in the source description. In addition, any data set can be contaminated by sound from other acoustic sources in the ocean. To overcome these problems, an iterative rotated coordinates inversion method [T. B. Neilsen, ‘‘An iterative implementation of rotated coordinates for inverse problems,’’ J. Acoust. Soc. Am. (submitted)] is employed in conjunction with a broadband bearing estimator [J. Krolik and D. Swingler, IEEE Trans. Acoust., Speech and Signal Process. 37, (1989)] and matrix filters [C. S. MacInnes, IEEE J. Ocean. Eng. (submitted)] to obtain estimates of the source locations and the sensitive geoacoustic parameters from multisource broadband data received on a horizontal line array (HLA). In the iterative inversion method, subsets of rotated coordinates are used to vary both the source and the sensitive environmental parameters in a series of simulated annealing inversions. The information contained in the rotated coordinates and corresponding eigenvalues determine which parameters are varied significantly in each simulated annealing inversion. [Work supported by ONR.]