Hierarchical optimization in H/sub /spl infin//

This paper considers a hierarchical optimal control problem which involves an optimal H/sub /spl infin//-norm cost in the primary problem and an H/sub /spl infin//-norm type or a quadratic secondary objective. Using allpass dilation techniques and results from superoptimal interpolation theory, it is shown that the problem can be reduced to a multidisk minimization in terms of a free parameter of reduced dimensions. Convex programming techniques may then be employed to obtain a numerical solution to the problem.