Design of Fractional Order Digital Differentiator Using RBF Interpolation Method

In this Paper, the fractional order digital differentiator has designed using Reciprocal Multiquadric radial basis function (RBF). First describe the radial basis function (RBF) interpolation method. Then, the non-integer delay sample estimation of discrete-time sequence is derived by using the radial basis function approach. Next, the Grunwald-Letnikov derivative and non-integer delay sample estimation is applied to obtain the transfer function of proposed method i.e. fractional order digital differentiator. The results of the proposed method are found to be better in performance compare to the conventional methods such as Fractional sample delay method and Frequency response approximation method. Finally, the application in digital image sharpening and parameter estimation of fractional noise process.