Output feedback H∞ control of sampled-data systems with parametric uncertainties

This paper investigates the problem of output feedback robust H∞ controller design for sampled-data systems with time-varying norm-bounded parameter uncertainties in the state matrix and input matrix. Attention is focused on the design of a causal output feedback sampled-data controller which guarantees the asymptotical stability of the closed-loop system and reduces the effect of the disturbance input on the controlled output to a prescribed H∞ performance bound γ for all admissible parametric uncertainties. Sufficient condition for the solvability of the problem is in terms of linear matrix inequalities (LMIs). It is shown that the desired output feedback H∞ controller can be constructed by solving certain LMIs. An illustrative example is given to demonstrate the effectiveness of the proposed method.