Constrained Infinite-Horizon Linear Quadratic Regulation of Discrete-Time Systems

We are concerned with the output norm-constrained infinite-horizon linear quadratic regulation problem, where the underlying state-control constraints are specified by curved, rather than polyhedral, surfaces. Each suboptimal problem admits an exact convex synthesis condition expressed by an increasing union of linear matrix inequalities and results in an eventually time-invariant controller satisfying the desired performance level subject to given constraints and closed-loop stability. The output norm-constrained minimum-time control problem is also dealt with as a corollary.