Fractional order oscillators with single non-zero transmission matrix element
This paper presents a study of fractional order oscillator design based on a matrix. The presented oscillator consists of a general two port network and three impedances. Only two port with single element in its transmission matrix is discussed which gives four possible networks. Different combinations for one element have been investigated. The impedances associated with the studied networks are series or parallel connection of resistors in addition to fractional order capacitors. The characteristic equation, oscillation frequency and condition for each combination are introduced. Numerical
Fractional order integrator/differentiator: FPGA implementation and FOPID controller application
This paper introduces two FPGA based design approaches of the fractional order integrator and differentiator using Grünwald Letnikov (GL) definition where fixed window and linear approximation approaches are considered. The main advantage of the linear approximation method is that it reduces the huge memory of the fractional order systems. One of the top applications of fractional calculus is the fractional order Proportional Integral Derivative (FOPID) controller. It has gained a great attention in academic studies and in industrial applications. The proposed approaches have been used as
FPGA Implementation of the Fractional Order Integrator/Differentiator: Two Approaches and Applications
Exploring the use of fractional calculus is essential for it to be used properly in various applications. Implementing the fractional operator Dα in FPGA is an important research topic in fractional calculus; in the literature, only a few FPGA implementations have been proposed due to the memory dependence of the fractional order systems. In this paper, FPGA implementations of fractional order integrator/differentiator based on the Grünwald-Letnikov (GL) operator are proposed. Two algorithms are developed based on look-up table and quadratic and piece-wise linear approximation approaches to
FPGA implementation of fractional-order integrator and differentiator based on Grünwald Letnikov's definition
The fractional-order derivative and integral of Grünwald Letnikov's definition are implemented based on FPGA for different fractional orders. A new algorithm is proposed to implement the GL integral based on linear approximation approach, where the memory dependency of the fractional order systems is eliminated. Moreover, the linear approximation design shows an improvement of 91% and 92% in the error and the mean percentage error compared with prior art. The proposed approach has been designed and implemented based on Verilog Hardware Description Language (HDL) and realized on Nexys 4 Artix-7
FPGA Implementation of Delayed Fractional-Order Financial Chaotic System
This paper proposes digital design and realization on Field-Programmable Gate Array (FPGA) of the Fractional-order (FO) delayed financial chaotic system. The system is solved numerically using the approximated Grünwald-Letnikov (GL) method. For the purpose of FPGA realization, the short memory principle and an approximate GL with limited window size are utilized. Lookup Tables (LUTs) are employed to store the required state values in order to compute the delayed terms. The proposed digital design is implemented on Artix-7 FPGA platform XC7A100T and realized experimentally on the oscilloscope
FPGA implementation of two fractional order chaotic systems
This paper discusses the FPGA implementation of the fractional-order derivative as well as two fractional-order chaotic systems where one of them has controllable multi-scroll attractors. The complete hardware architecture of the Grünwald-Letnikov (GL) differ-integral is realized with different memory window sizes. As an application of the proposed circuit, a complete fractional-order FPGA implementation of Liu chaotic system is introduced with different fractional-orders. Moreover, a fractional-order controllable heart and V-shape multi-scrolls chaotic systems are verified in the case of
Fractional controllable multi-scroll V-shape attractor with parameters effect
This paper is an extension of V-shape multi-scroll butterfly attractor in the fractional-order domain. The system complexity is increased by the new dynamics introduced by the fractional operator which make it more suitable for random signal generator. The effect of system parameters on controlling the attractor shape is investigated and compared with the integer order attractor. Maximum Lyapunov exponent is calculated for both integer and fractional orders attractors to prove the complexity of fractional chaotic system using time series. © 2017 IEEE.
Two topologies of fractional-order oscillators based on CFOA and RC networks
This paper presents two general topologies of fractional order oscillators. They employ Current Feedback Op-Amp (CFOA) and RC networks. Two RC networks are investigated for each presented topology. The general oscillation frequency, condition and the phase difference between the oscillatory outputs are investigated in terms of the fractional order parameters. Numerical simulations and P-Spice simulation results are provided for some cases to validate the theoretical findings. The fractional order parameters increase the design flexibility and controllability which is proved by the provided
Fractional-order inverting and non-inverting filters based on CFOA
This paper introduces a study to generalize the design of a continuous time filters into the fractional order domain. The study involves inverting and non-inverting filters based on CFOA where three responses are extracted which are high-pass, band-pass and low-pass responses. The proposed study introduces the generalized formulas for the transfer function of each response with different fractional orders. The fractional-order filters enhance the design flexibility and controllability due to the extra degree of freedom provided by the fractional order parameters. The general fundamentals of
Fractional Order Oscillator Design Based on Two-Port Network
In this paper, a general analysis of the generation for all possible fractional order oscillators based on two-port network is presented. Three different two-port network classifications are used with three external single impedances, where two are fractional order capacitors and a resistor. Three possible impedance combinations for each classification are investigated, which give nine possible oscillators. The characteristic equation, oscillation frequency and condition for each presented topology are derived in terms of the transmission matrix elements and the fractional order parameters α
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