MODEL-REDUCTION OF NONSQUARE LINEAR MIMO SYSTEMS USING MULTIPOINT MATRIX CONTINUED-FRACTION EXPANSIONS

This paper deals with the multipoint Cauer matrix continued-fraction e xpansion (MCFE) for model reduction of linear multi-input multi-output (MIMO) systems with various numbers of inputs and outputs. A salient feature of the proposed MCFE approach to model reduction of MIMO syste ms with square transfer matrices is its equivalence to the matrix Pade approximation approach. The Cauer second form of the ordinary MCFE fo r a square transfer function matrix is generalized in this paper to a multipoint and nonsquare-matrix version. An interesting connection of the multipoint Cauer MCFE method to the multipoint matrix Pade approxi mation method is established Also, algorithms for obtaining the reduce d-degree matrix-fraction descriptions and reduced-dimensional state-sp ace models from a transfer function matrix via the multipoint Cauer MC FE algorithm are presented. Practical advantages of using the multipoi nt Cauer MCFE are discussed and a numerical example is provided to ill ustrate the algorithms.