Methods of solving a polynomial equation for an H/sub infinity / optimal control problem for a single-input single-output discrete-time system

A polynomial equation for the H/sub infinity / optimal control problem is reduced to a nonlinear algebraic equation. Two methods are proposed for solving the algebraic equation. One method uses the singularity of a linear algebraic equation as the optimality index. The other gives an approximate solution by solving an eigenvalue problem. A numerical example is presented.<
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