Frequency response model identification method for discrete-time processes with final cyclic-steady-state

A new non-parametric process identification method is proposed to obtain the discrete-time frequency response model from process input and output data. Existing discrete-time Fourier transform approach can be applied to only the case that the initial part and the final part of the process data are zero-steady-state. The proposed method using a new transform can estimate the frequency response model from more various cases including initial-steady-state/final-steady-state and initial-steady-state/final-cyclic-steady-state. It can estimate exact frequency response model because no approximations are used in developing the proposed algorithm. Also, the proposed method can still provide exact model even in the case of static disturbances.