Abstract

In this paper, performance limitations in the linear control of general linear discrete-time scalar systems are considered. The performance is measured with the 2-norm of an error function which, at the same time, ensures that the closed loop poles lie in a prescribed region. The deleterious effect of this constraint on a classical performance measurement is also quantified, in such a way, that the interplay between the size of the desired region and structural features of the plant is revealed.