Dynamic Output Feedback Control Synthesis with Mixed Frequency Small Gain Specifications

This paper is concerned with the control synthesis problem via dynamic output feedback for linear continuous-time systems with mixed frequency small gain specifications. A new method for designing dynamic output feedback controllers is presented such that the resulting closed-loop systems are asymptotically stable and meet the requirements of small gain specifications in both finite frequency ranges and the entire frequency range. The design conditions are given in terms of solutions to a set of linear matrix inequalities (LMIs). Finally, a numerical example is given to illustrate the design procedure and the advantage of the proposed method in comparison with the existing one.