Number of Parametrization of Discrete-Time Systems without Unit-Delay Element: Single-Input Single-Output Case

In this paper, we consider the parametrization of the
discrete-time systems without the unit-delay element within the
framework of the factorization approach. In the parametrization,
we investigate the number of required parameters. We consider
single-input single-output systems in this paper. By the investigation,
we find, on the discrete-time systems without the unit-delay element,
three cases that are (1) there exist plants which require only one
parameter and (2) two parameters, and (3) the number of parameters
is at most three.

Authors:

• Kazuyoshi Mori

Keywords:

• Linear systems
• parametrization
• Coprime Factorization
• number of parameters.

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