A general theory for the Wiener-Hopf design of multivariable control systems

Multivariable control system design in a quadratic cost setting is treated for a completely general configuration. The class of all controllers is determined for which the general configuration is internally asymptotically stable and a quadratic cost functional is finite. This controller class is parameterized in terms of an arbitrary real rational strictly-proper matrix Z(s), which is analytic in the closed right-hand side of the s-plane. The choice Z≡0 gives the controller which minimizes the quadratic cost functional