Abstract. In the paper, a new method for solution of linear discrete-time fractional-order state equation is presented. The proposed method is simpler than other methods using directly discrete-time version of the Grünwald-Letnikov operator. The method is dedicated to use with any approximator to the operator expressed by a discrete transfer function, e.g. CFE-based Al-Alaoui approximation. A simulation example confirms the usefulness of the method. A new algorithm for a CFE-approximated solution of a discrete-time noninteger-order state equationbstract. In the paper, a new method for solution of linear discrete-time fractional-order state equation is presented. The proposed method simpler than other methods using directly discrete-time version of the Grünwald-Letnikov operator. The method is dedicated to use with ny approximator to the operator expressed by a discrete transfer function, e.g. CFE-based Al-Alaoui approximation. A simulation example onfirms the usefulness of the method. Many real applications, to mention model-based conrol, model-based fault detection, require to implement a oninteger-order model at a digital platform like PLC or PGA. Known discrete-time state space models of nonintegerrder systems are typically based on the Grünvald-Letnikov GL) definition. An accurate implementation of this model, in articular at the bounded resource platforms, requires a (very) ong-length approximation of the GL-based system [33].The purpose of this paper is to propose a new, discrete-time tate space model of a noninteger-order system, constructed ith the use of the continuous fraction expansion (CFE) imlemented for the Al-Alaoui operator. The use of such an aproximant enables to obtain a much more effective model in hat the memory length is quite low. This recommends its use t industrial digital platforms.The paper is organized as follows. Heaving recalled the ackground of the paper in Section 1, Section 2 outlines the undamentals of fractional-order calculus and introduces a operator is defined aswhere a and t denote time limits for calculation of the operator, α ∈ R denotes the noninteger order of the operation.Next, an idea of the Gamma (Euler) function (see for example [12]) can be given: DEFINITION 2. The Gamma function is defined asThe fractional-order, integro-differential operator (1) can be described by different definitions, given by Grünvald and Letnikov (GL definition), Riemann and Liouville (RL definition) and Caputo (C definition). All these definitions are given below. With respect to particular additional assumptions these definitions can be considered equivalent. A new algorithm for a CFE-approximated solution of a discrete-time noninteger-order state equationAbstract. In the paper, a new method for solution of linear discrete-time fractional-order state equation is presented. The proposed method is simpler than other methods using directly discrete-time version of the Grünwald-Letnikov operator. The method is dedicated to use with any approximator to the operator expressed by a discrete tra...