Digital resampling using Farrow structures

Abstract: Farrow filters allow to develop universal oversamplers for fractional delay correction and sampling rate conversion. The use of cubic Lagrangian interpolation in Farrow filter does not allow to provide processing bandwidth more than 0.4 of sampling frequency, and also does not guarantee smoothness of impulse response of the interpolator. In this paper, we propose Farrow filter structures based on 3rd, 5th and 7th order Hermite splines using a high order differentiator. The proposed filters increase the processing bandwidth up to 0.8 of sampling frequency by increasing the order of the polynomial with additional constraints on the continuity of the derivatives at the interpolation nodes.