FPGA implementation of fractional-order integrator and differentiator based on Grünwald Letnikov's definition

Abstract

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 XC7A100T.