INVERSION IN SHALLOW-WATER USING THE WKB MODAL CONDITION

In this paper, we propose an efficient scheme for extracting the compl ex bottom reflection coefficient (phase and amplitude) in a shallow wa ter waveguide by using the WKB modal condition. The input data are the measured modal wavenumber (k(m)) and the modal attenuation (beta(m)). The main advantages of this scheme are: 1) it is efficient, because t here are no replica calculations as in the conventional matched field processing (MFP) scheme, 2) the inverted error induced by the ''noise' ' of the contaminated data can be estimated analytically, and 3) the i mpact of the environmental (SSP) mismatch can also be estimated analyt ically. Numerical simulations illustrate that the proposed scheme work s well in different scenarios of shallow water waveguides.