Abstract. We report on a new iterative approach for finding a global minimizer of the Tikhonov functional with a special class of nonlinear operators F. Assuming that the operator itself can be decomposed into (or approximated by) a sum of a linear and a bilinear operator, we introduce a two-step iteration scheme based on an outer iteration over the regularization parameter α and an inner iteration with a steepest descent method. Finally we present numerical results for the reconstruction of the emission function in single-photon emission computed tomography.

Print publication: Issue 2 (April 2002)
Received 25 September 2001
Published 7 March 2002