Title: Identifiability of Linear Time Invariant System
Abstract: In this paper, identifiability of unknown parameters of linear time invariant systems is considered. Some new conditions are given for the identifiability when parameters are to be identified from input-output data.Necessary and sufficient conditions for global identifiability are given which are more practical than earlier results. A frequency condition concerning the probing signals for identification is given, and it plays an important role in the derivation of global identifiability conditions. Results given in this paper for the probing signals are similar to the conditions given earlier for the convergence of adaptive observers. A necessary and sufficient condition for local identifiability is also given using global results.