CW Mode Structure and Constraint Beamforming in a Waveguide with Unknown Large Inclusions

In this paper, we continue our study in combining the matched-field method with the boundary integral equation method from inverse scattering theory to study a sound source localization problem in a shallow ocean with an unknown large inclusion. We assume that there is an unknown inclusion embedded in a shallow water waveguide. The existence of the unknown inclusion changes the propagating field greatly. Therefore, neglecting the existence of the unknown inclusion will lead to substantial mismatching in the matched-field signal processing. To compensate for environmental unknown, we send in a number of acoustic waves emitted from known locations, which scatter off the unidentified inclusion and are received by a hydrophone array. We discuss the CW mode structure in such a waveguide, then present a method to generate approximately the replica field from an acoustic source using the previously recorded information. Combining the information of these scattered waves and the signal from th..