Multigrid Implementation of Regularized Image Reconstruction Methods for Limited-Data Tomography

Rafal Zdunek, Andrzej Prałat

Institute of Telecommunications and Acoustics, Wroclaw University of Technology Wybrzeze Wyspianskiego 27, 50 – 370 Wroclaw, Poland, Email: rafal@zue.ita.pwr.wroc.pl

ABSTRACT

The paper presents a numerical analysis of the multigrid implementation of the Iterative Tikhonov Regularization (ITR) method applied to image reconstruction in EM geotomography. In this tomographical technique, the angular range of rays is sharply limited whereby an ill-posed problem has to be solved. It is demonstrated that for noise-free data the multigrid implementation handles the problem much better than the standard single-grid technique. For noisy data the results are less promising.

Keywords Multigrid image reconstruction, borehole tomography, ill-posed problems, electromagnetic geotomography