IMPROVED ROBUST STABILITY BOUNDS FOR DISCRETE-TIME LINEAR REGULATORS WITH COMPUTATIONAL DELAYS

Recently obtained stability robustness bounds on linear time-varying perturbations of an asymptotically stable linear time-invariant discrete-time system are applied to linear regulators with computational delays. The bounds were developed using Lyapunov theory and singular value decomposition for unstructured and structured time-varying perturbations. The new structured perturbation bound may provide improved results for the elemental perturbations over a bound based on the unstructured perturbation bound of Ishihara (1988, Automatica, 24, 696-700), as indicated both by an example and by sufficient conditions. © 1990.