Robust pole-assignment design for perturbed discrete time-delay systems

The sufficient condition to guarantee robust pole location within a prescribed circular region for perturbed discrete time-delay systems via a state feedback controller is introduced. By the sufficient condition, the tolerable parametric perturbation bounds that ensure all the poles of perturbed discrete time-delay systems to remain inside the desired disk D(e, f), centered at (e, 0) with radius f<1 and |e|+f<1, can be estimated. The stability radius of matrix is employed to investigate the problem, and the result obtained by the presented sufficient condition is a significant improvement over the method reported by Lee et al. Finally, our result is demonstrated by an example.<>