We propose an approach to characterize the AC underwater radiation produced by a ship over a shallow water medium using dipole sources distributed over an interior surface to the ship. The proposed approach relies in the accurate and efficient representation of dipole sources over the shallow water medium that characterize the behavior of the electric or magnetic field. The approach is reduced to the solution of the resultant matrix system from the dipole representation. These systems are ill-posed, i.e., if the matrix systems are not solved by special regularization methods, the resultant solution will amplify the measurement noise. The regularization method applied is the least squares QR iterations combined with a new stopping rule that uses a numerical estimate of the measurement noise. Numerically generated data is used to study the validity of the different dipole representations. Finally we validate our methodology using magnetic measurements that result from degaussing coils of a mid-size vessel.
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