Robust H/sub /spl infin// filtering of linear systems with time-varying delay

A robust delay-dependent H/sub /spl infin// filtering design is proposed for linear continuous systems with parameter uncertainty and time-varying delay. The resulting filter is of the general linear observer type and it guarantees that the induced L/sub 2/-norm of the system, relating the exogenous signals to the estimation error, is less than a prescribed level for all possible parameters that reside in a given polytope. Our design is based on the application of the descriptor model transformation and Park´s inequality for the bounding of cross terms and is expected to be the least conservative as compared to existing design methods. A numerical example indeed demonstrates this advantage of the new filtering scheme.