Some results on pole-placement and reachability
It is proved that a 2-dimensional system (F,G) over a projective free ring is pole-assignable if and only if im G contains a unimodular element. Further it is shown that im G contains a unimodular element iff \(F^{-1}(im G)\) contains a unimodular element. Some observations on reachability are also mentioned in the last section.
scientific article; zbMATH DE number 3920317