Kybernetika

In this paper we present an input-output point of view for the problem of closed loop norm minimization of stable plants when a decentralized structure and a disturbance decoupling property are imposed on the controller. We show that this problem is convex and present approaches to its solution in the optimal $\ell_1$ sense in the nontrivial case which is when the block off-diagonal terms of the plant have more columns than rows.