Model reduction of two-dimensional discrete-time systems based on finite-frequency approach

This paper deals with the model reduction problem of two-dimensional (2-D) discrete-time systems described by the Roesser model. Different from existing full-frequency methods, we propose a finite-frequency model reduction method for 2-D Roesser systems. By the generalized Kalman-Yakubovich-Popov (GKYP) lemma for 2-D systems, sufficient conditions are developed for model reduction of 2-D Roessor systems over low-frequency, and middle-frequency, respectively. The proposed finite-frequency model reduction method can get a better approximation accuracy than the existing full-frequency ones over the finite-frequency ranges. The effectiveness of the proposed method is illustrated by a numerical example.