A note on the convergence of a class of adaptive optimal identifiers

This paper proposes a unifying framework for the convergence analysis of a class of adaptive optimal identifiers. The considered class of identifiers is constructed from the sequence of minimizing sets of a family of objective functions. For the purpose of the analysis we introduce a generalized version of the classical persistence of excitation condition. Based on this an Input-to-State-Stability (ISS)-type of property is derived for the studied class of adaptive estimators.