ON THE USE OF REGULARIZATION TECHNIQUES IN NUMERICAL INVERSE-SCATTERING SOLUTIONS FOR MICROWAVE IMAGING APPLICATIONS

This paper deals with integral-equation-based numerical methods for mi crowave imaging using regularization procedures to overcome ill-condit ioning problems, The strong dependence of reconstruction quality on '' a priori'' information is discussed. Such information is required to s elect a suitable number of independent columns when using truncated ps eudoinversions (or other regularization parameters, in different cases ) for accurate dielectric reconstructions. Moreover, a criterion for t he choice of the optimal number of independent columns is proposed, an d the possibility of making this choice less critical by using a multi view version of the method is explored. Finally, a modified procedure is presented that further increases the range from which to choose the number of independent columns that allows one to achieve acceptable r econstructions.