Mixed l 2 /l ∞ / H ∞ estimation for uncertain discrete-time systems

A new criterion of l 2 -l infin / H infin performance is established by introducing a slack matrix. The designed estimator possesses two outputs which are respectively used to estimate the different estimated signals with l 2 -l infin and H infin performances. Conservatism inherent in the quadratic framework can be reduced in robust synthesis of systems with polytopic uncertainties, since the parameter dependent Lyapunov functions can be adopted. A numerical example is included to illustrate the feasibility and advantage of the proposed representations.