Abstract
The main goal of this work is to exploit different tools in order to approximate a general double exponent fractional-order transfer function. Through the appropriate selection of the two fractional orders of this function, different types of filters can be derived. The investigated approximation tools are either curve fitting based tools or the Padé approximation tool, and the derived approximated transfer functions in all cases have the form of rational integer-order polynomials, which can be easily realized electronically.






Similar content being viewed by others
References
A.M. AbdelAty, A.S. Elwakil, A.G. Radwan, C. Psychalinos, B. Maundy, Approximation of the fractional-order Laplacian s\(^{\alpha }\) as a weighted sum of first-order high-pass filters. IEEE Trans. Circuits Syst. II Express Briefs 65(8), 1114–1118 (2018)
A.S. Ali, A.G. Radwan, A.M. Soliman, Fractional order Butterworth filter: active and passive realizations. IEEE J. Emerg. Selected Topics Circuits Syst. 3(3), 346–354 (2013)
K. Bingi, R. Ibrahim, M.N. Karsiti, S.M. Hassam, V.R. Harindran, Frequency response based curve fitting approximation of fractional-order PID controllers. Int. J. Appl. Math. Comput. Sci. 29(2), 311–326 (2019)
K. Bingi, R. Ibrahim, M.N. Karsiti, S.M. Hassan, V.R. Harindran, Fractional-order Systems and PID Controllers: Using Scilab and Curve Fitting Based Approximation Techniques (Springer, Berlin, 2019)
T.J. Freeborn, B. Maundy, A. Elwakil, Fractional resonance-based \({RL}_{\beta }{C}_{\alpha }\) filters. Math. Prob. Eng. (2013). https://doi.org/10.1155/2013/726721
A.M. Hassanein, A. Soltan, L.A. Said, A.H. Madian, A.G. Radwan Analysis and design of fractional-order low-pass filter with three elements of independent orders. In: 2019 Novel Intelligent and Leading Emerging Sciences Conference (NILES), vol. 1 (IEEE, 2019) pp. 218–221
S. Kapoulea, G. Tsirimokou, C. Psychalinos, A.S. Elwakil, Employment of the Padé approximation for implementing fractional-order lead/lag compensators. AEU Int. J. Electron. Commun. 120, 153203 (2020)
B. Krishna, Studies on fractional order differentiators and integrators: a survey. Sig. Process. 91(3), 386–426 (2011)
L. Lorentzen, Padé approximation and continued fractions. Appl. Numer. Math. 60(12), 1364–1370 (2010)
A. Oustaloup, F. Levron, B. Mathieu, F.M. Nanot, Frequency-band complex noninteger differentiator: characterization and synthesis. IEEE Trans. Circuits Syst. I Fundam. Theory Appl. 47(1), 25–39 (2000)
A.A. Ozdemir, S. Gumussoy, Transfer function estimation in system identification toolbox via vector fitting. IFAC-PapersOnLine 50(1), 6232–6237 (2017)
A.G. Radwan, A.S. Elwakil, A.M. Soliman, On the generalization of second-order filters to the fractional-order domain. J. Circuits Syst. Computers 18(02), 361–386 (2009)
A.G. Radwan, A.M. Soliman, A.S. Elwakil, First-order filters generalized to the fractional domain. J Circuits Syst. Computers 17(01), 55–66 (2008)
A. Soltan, A.G. Radwan, A.M. Soliman, Fractional order filter with two fractional elements of dependant orders. Microelectron. J. 43(11), 818–827 (2012)
G. Tsirimokou, A systematic procedure for deriving RC networks of fractional-order elements emulators using MATLAB. AEU-Int. J. Electron. Commun. 78, 7–14 (2017)
G. Tsirimokou, C. Psychalinos, A.S. Elwakil, Fractional-order electronically controlled generalized filters. Int. J. Circuit Theory Appl. 45(5), 595–612 (2017)
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
This research is co-financed by Greece and the European Union (European Social Fund-ESF) through the Operational Programme “Human Resources Development, Education and Lifelong Learning” in the context of the project “Strengthening Human Resources Research Potential via Doctorate Research-2nd Cycle” (MIS-5000432), implemented by the State Scholarships Foundation (IKY).
This article is based upon work from COST Action CA15225, a network supported by COST (European Cooperation in Science and Technology.
Rights and permissions
About this article
Cite this article
Kapoulea, S., Psychalinos, C. & Elwakil, A.S. Double Exponent Fractional-Order Filters: Approximation Methods and Realization. Circuits Syst Signal Process 40, 993–1004 (2021). https://doi.org/10.1007/s00034-020-01514-7
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00034-020-01514-7