On decentralized estimation†
Dragoslav D. Šiljak, M. B. Vukčević · International Journal of Control · 1978
A multilevel scheme is proposed to construct decentralized estimators for large linear systems. The scheme is numerically attractive since only observability tests of low-order subsystems are required. Equally important is the fact that the constructed estimators are reliable under structural perturbations and can tolerate a wide range of non-linearities in coupling among the subsystems.