On the Simplification of Transfer Functions of Linear Dynamical Systems

Abstract

A method for the simplification of transfer functions of linear dynamical systems is presented. The sampled input and output data of the original system are used, and the least squares fit is applied to obtain a low-order model. When the order of a simplified model is equal to m, it is necessary to compute 2m × 2m matrices in the usual methods. However, if the impulse response of the original system is used, the simplified model can be obtained by computing m × m matrices. Since the computational procedures are simple, this method is useful for obtaining a numerical solution on a digital computer.