Fading regularization MFS algorithm for the Cauchy problem associated with the two-dimensional Helmholtz equation

In this paper, we combine the fading regularization method with the method of fundamental solutions (MFS) and investigate its application to the Cauchy problem for the two-dimensional Helmholtz equation. We present a numerical reconstruction of the missing data on an inaccessible part of the boundary from the knowledge of overprescribed noisy data taken on the remaining accessible boundary part for both smooth and piecewise smooth two-dimensional geometries. The accuracy, convergence, stability and efficiency of the proposed numerical algorithm, as well as its capability to deblur the noisy data, are validated by three numerical examples.