Decentralized H∞ controller design: an LMI approach

Considers decentralized H_∞ controller design problems for multi-channel linear time-invariant systems. Our interest is focused on dynamic output feedback, and our discussion concerns both continuous-time systems and discrete-time ones. The decentralized H_∞ control problems are expressed as feasibility problems of bilinear matrix inequalities (BMIs) with respect to variables of a coefficient matrix defining the controller and a Lyapunov matrix. To deal with the BMIs, we propose to set the Lyapunov matrix as block diagonal appropriately according to the desired order of the controller so that the BMIs; are reduced to linear matrix inequalities (LMIs) which are sufficient to the BMIs but much more tractable.