Stable denominators for the simplification of z-transfer functions
type: Item
instance of: scholarly article
title: Stable denominators for the simplification of z-transfer functions
zbMATH Open document ID: 0569.93063
DOI: 10.1016/0016-0032(85)90003-1
author: Constantine P. Therapos
published in: Journal of the Franklin Institute
publication date: 1985-01-01T00:00:00Z
review text: A well-known discrete stability test is used to derive from the denominator D(z) of a given stable high-order transfer function G(z), the denominator of a low-order approximant of G(z). The proposed method, based on the truncation and inversion of a continued fraction formed with the coefficients of D(z), yields a reduced denominator d(z) of degree, say m, which is always stable. Furthermore, depending on the neglected parts of the continued fraction, d(z) approximates \(m_ 1\) and \(m_ 2=m-m_ 1\) zeros of D(z), located very near the points \(z=1\) and \(z=-1\), respectively. In the special case \(m_ 1=m\), d(z) is identical to the polynomial obtained by applying to D(z) the indirect technique, which combines the bilinear transformation with the Routh or the Schwarz approximation method.
Mathematics Subject Classification ID: 93D99
Mathematics Subject Classification ID: 30B70
Mathematics Subject Classification ID: 93B17
Mathematics Subject Classification ID: 41A20
zbMATH DE Number: 3910277
zbMATH Keywords: discrete stability test
zbMATH Keywords: transfer function
zbMATH Keywords: continued fraction
zbMATH Keywords: bilinear transformation
MaRDI profile type: Publication
full work available at URL: 0016-0032(85)90003-1
OpenAlex ID: W2003199252
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description: scientific article; zbMATH DE number 3910277