Application of inversion methods in solving ill-posed problems for magnetic parameter identification of steel hull vessel

Abstract

Recovery of magnetic target parameters from magnetic sensor measurements has attracted wide interests and found many practical applications. However, difficulties present in identifying the permanent magnetization due to the complications of magnetization distributions over the ship body, and errors and noises of measurement data degrade the accuracy and quality of the parameter identification. In this paper, we use a two step sequential solutions to solve the inversion problem. In the first step, a numerical model is built and used to determine the induced magnetization of the ship. In the second step, we solve a type of continuous magnetization inversion problem by solving 2D Fredholm integral equation of the 1st kind. We use parallel computing which allows solve the inverse problem with high accuracy. In additional, Tikhonov regularization has been applied in solving the inversion problems. The proposed methods have been validated using simulation data with added noises.