ON THE VALIDITY OF REALIZABLE PHYSICAL APPROXIMATIONS TO δ(t) INPUT IMPULSES TO OBTAIN IMPULSE RESPONSES. APPLICATION TO SYNTHETIZE DISCRETE-TIME MODELS FOR LTI SYSTEMS
نویسندگان
چکیده
The aim of this work is to study the validity of impulse approximations to model discrete systems using filter-based identification methods. Even when impulse inputs possess an inherent error due to the physical impossibility of generation of ideal impulses, they are of particular practical interest when treating discrete-time systems where the analytical resolution becomes very complex or even unfeasible. In particular, when handling numerical response impulse simulations the goodness of the results obtained highly depends on the precision of the δ(t) distribution construction. In the first part of the paper an analytical proof ratifying the validity of these approximations is presented, while the second part is devoted to obtain discrete-time models for LTI systems, affording three different filter-based methods to identify the discrete transfer function from the sampled response of the system when excited by an approximated impulsive input.
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