On the factorization of rational matrices depending on a parameter
Consider the equation R \(*R=G\) with unknown \(n\times m\) matrix R on the ring S consisting of real rational and proper stable functions. Then the author shows the following relation to a result of \textit{D. Youla} [IRE Trans. Inform. Theory 17, 172-189 (1961)]: For G depending in a certain regular way on a parameter, one can choose the solution R behaving the same as G. The result yields a new (third) metrization of the graph topology due to \textit{M. Vidyasagar} [IEEE Trans. Autom. Conrol. AC 29, 403-418 (1984; Zbl 0536.93042)] on the transfer matrices of linear systems.
scientific article; zbMATH DE number 4044521