Riccati equation approach to maximizing the complex stability radius by state feedback

Abstract
In this paper we study the problem of maximizing the complex stability radius of a linear time-invariant state-space system by linear state feedback, We show that the supreme achievable stability radius can be characterized via parametrized Riccati equations. The dependency on the parameters is examined and the limiting behaviour described. Finally, the relationship between the supremum of the achievable stability radii and the distance of a system from non-stabilizabilky is investigated.