A metrology system may arrange metrology measurements for a plurality of metrology targets distributed in a plurality of fields on one or samples into a signal vector, where the metrology measurements associated with the metrology targets in each of the plurality of fields are grouped within the signal vector. The system may further decompose the signal vector into reconstruction vectors associated with different spectral components of the signal vector. The system may further classify a subset of the reconstruction vectors as components of a metrology model, where a sum of the components corresponds to a metrology model describing the metrology measurements on the one or more samples. The system may further generate control signals to control one or more processing tools based on the metrology model.