Observers for linear systems with arbitrary plant disturbances
Kinattingal Sundareswaran, Peter J. McLane, Mohamed M. Bayoumi · IEEE Transactions on Automatic Control · 1977
This paper shows how to choose observer parameters so that its estimation error is independent of arbitrary plant disturbances. Contrary to previous research the plant disturbances are not assumed to have any mathematical structure. Also presented are conditions under which an observer can reject plant disturbances and also have its eigenvalues arbitrarily assigned.