Adaptive stabilization of linear systems with unknown high-frequency gains

This paper presents an algorithm for adaptively controlling a single-input, single-output process admitting an <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</tex> -dimensional, minimum-phase linear model of relative degree n * , with unknown parameters. A priori knowledge of the sign of the model's high frequency gain is not required, and a sufficiently rich probing signal is not needed for stabilization.