Reduced-order Construction of H∞ State Feedback Law for Discrete-time Single Input-delayed Systems

KYP equations for discrete time-delay systems involve computational difficulty. This paper addresses efficient construction of the H∞ state feedback law for discrete-time single input-delayed systems. The min-max optimization is adopted to construct the stabilizing solution of the KYP equation for the input-delayed case from that for the delay-free case. The consistency with the previous results based on the J-spectral factorization theory is also discussed.