SAMPLED-DATA MINIMUM H-INFINITY-NORM REGULATION OF LINEAR CONTINUOUS-TIME SYSTEMS USING MULTIRATE-OUTPUT CONTROLLERS

This paper deals with the problem of designing multirate-output controllers for sampled-data H-infinity-optimal control of linear continuous-time systems. Two formulations of the problem are studied. In the first, the intersample behavior of the disturbance and the controlled output signals is not considered, whereas in the second the continuous-time nature of these signals is taken into account. It is shown that, in both cases and under appropriate conditions, it is plausible to reduce the respective initial problem to an associated discrete-time H-infinity-optimization problem for which a fictitious static state feedback controller is to be designed. This fact has a beneficial influence on the theoretical and numerical complexity of the problem, since only one algebraic Riccati equation is to be solved here, as compared to two algebraic Riccati equations needed in known techniques concerning the H-infinity-optimization problem with dynamic measurement feedback.