STABILITY OF SOLUTIONS OF LINEAR DIFFERENCE-EQUATIONS WITH PERIODIC COEFFICIENTS

This paper represents the last technical contribution of Professor Pat rick Parks before his untimely death in February 1995. The remaining a uthors of the paper, which was subsequently completed, wish to dedicat e the article to Patrick. A frequency criterion for the stability of s olutions of linear difference equations with periodic coefficients is established. The stability criterion is based on a consideration of th e behaviour of a frequency hodograph with respect to the origin of coo rdinates in the complex plane. The formulation of this criterion does not depend on the order of the difference equation.