Decentralised output-feedback controller syntheses with restricted frequency-domain specifications via generalised Kalman–Yakubovich–Popov lemma: a unified approach

This study is concerned with output-feedback H-infinity controller synthesis in finite frequency domain for continuous-time multi-channel linear systems. The recently developed results of full-order centralised H-infinity control theory in this field are extended to the subject of decentralised control. Both the block-diagonal reduced-order dynamic and static controller designs are discussed in a unified manner. Sufficient solvability conditions are given in terms of linear-matrix-inequalities. A numerical example is provided that establishes the efficacy of the proposed controller syntheses.