A quadratic approach is used to find the unknown resistivity of a cond
ucting body. The resistivity variation are supposed to be spatially lo
calized. The multiresolution analysis is discussed in order to obtain
a good estimate of the resistivity profile with a limited number of un
known parameters. The method allows to identify the regions where the
perturbations may be localized and to retrieve the unknowns parameters
only in those regions. Some numerical results show the main features
of the proposed approach.