Extended Dominance Condition for Schur Stability of Real Polynomials

Abstract

A known sufficient condition called “dominance condition” for Schur stability of real polynomials is extended in such a way that the equality is allowed in the inequality relation of the original condition. It is pointed out that two extra inequalities are needed for the extended condition to remain intact, being still a simple sufficient condition for stability of the polynomials. Some cases where the original dominance condition is also a necessary one are identified.