Complete identification of dynamic physical systems using a five parameter model

System identification is important in science and engineering. This contribution proposes a simple yet elegant scheme for identifying a fractional order dynamic system based on its observed response to a standard excitation. Our approach consists in obtaining and solving a set of simultaneous linear equations connecting the parameters to yield the desired estimates. To minimise the effect of noise, we have performed an in-depth analysis of the Grunwald-Letnikov definition and, as far as we know, are the first ones to do so. Results show that the proposed method offers a very high degree of accuracy even for erroneous data.