Journal of Control and Systems Engineering
Journal of Control and Systems Engineering(JCSE)

Simple Criteria for Stability and Instability of Discrete-Time Systems
The contribution of the article is threefold. In the first part of this article the literature is surveyed for simple computation-free criteria for the verification of stability/instability of discrete-time systems. Numerous results are reported which are missing in standard texts on discrete-time control systems. In the second part new results in the same spirit are presented. They are in terms of necessary or sufficient conditions, free from computational burden, and thus much appealing to the systems and control community. These criteria are derived using the Rouche’s theorem which although has found numerous applications in systems and control theory is not unanimously known by engineering academicians. The third part of this article is a concise introduction to this theorem. The literature is also surveyed for its applications in the field and several ways of its manifestation are reported and classified.
Keywords:Discrete-Time Systems; Robustness; Rouche’s Theorem; Stability Criteria
Author: Yazdan Bavafa-Toosi


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