Abstract:
Inversion for environmental parameters using both simulated and actual experimental data was performed based on the propagation results for presumably unknown broadband sources. The environment is a shallow- water environment and all computations are performed in the time domain. The inversion is based on the least-square comparison between the results of a source deconvolution for each of several receivers. Because single-receiver source deconvolution in underwater acoustics is an intrinsically ill-posed problem, the Tichonov--Philips regularization is incorporated into the current procedure. The method is made efficient by the use of a new deconvolution algorithm that specifically takes advantage of the triangular Toeplitz structure of the propagation matrix [J. Roginsky and G. W. Stewart, J. Acoust. Soc. Am. 97, 3290 (A) (1995)]. The advantages of this method are: (a) The process can be performed with as few as two receivers; (b) no a priori source information is required; (c) due to one's ability to work with shorter time windows, the procedure can be made faster than a corresponding frequency domain approach. [Work supported by ONR.]