Digital Identification of A Continuous Time System and Some Related Problems

A scheme is presented in the paper for digital identification of a continuous time system. The identifier proposed operates on the sampled input outpt data, but generates an estimate of the unknown continuous time system directly. Convergence analysis of the identifier is given in the paper. Also dicussed in the paper are some related problems. In particular, convergence of the identifier requires the persistent excitation condition on some signals in the identfication loop and that condition is reduced to the controllablity and observability of the sampled system of the unknown continuous time system. A result is derived in the paper concerning the controllability and observability of sampling an unknown continuous time system.