Frequency domain conditions for robust H-2 performance

This paper presents frequency domain conditions to analyze H-2, performance in the worst case over structured uncertainty in the system. These conditi ons are convex feasibility tests in terms of Linear matrix inequalities acr oss frequency, of the same nature as tests available for robust stability o r H-infinity performance. By introducing a deterministic generalization of the H-2 criterion, the different versions of this test are characterized as necessary and sufficient for robust performance under corresponding classe s of dynamic uncertainty.