The parameterized Lyapunov bounding technique of Haddad and Bernstein
is extended to include an H-infinity-disturbance attenuation constrain
t. The results presented in this paper provide a framework for designi
ng fixed-order (i.e., full- and reduced-order) controllers that guaran
tee robust H-2 and H-infinity performance in the presence of structure
d constant real parameter variations in the state space model.