Solution of discrete H∞ optimal control problems using a state-space approach

The solution of the H_∞ optimal control problem is considered for discrete-time systems which are represented in state equation form. The solution of the Nehari one-block problem is very straightforward and an explicit solution is obtained. The results are more complicated than for the continuous-time problem but are nevertheless simple to implement in standard CAD (computer-aided design) packages. The state space solution is linked to the alternative polynomial matrix solution of the H_∞ control, thereby providing useful insights into the two approaches