Multivariable stability margin optimization with decoupling and output regulation

A procedure is developed for maximizing frequency-weighted stability margin singular values for a multivariable linear time-invariant feedback control systems subject to design constraintsrequiring decoupling and asymptotic tracking in the presence of unstable command and disturbance signals, and closed-loop stability. The results are derived using Sarason's H∞ optimal interpolation results together with a new multivariable realizability Lemma.