A universal interpolative filter for low-pass and bandpass signals-CSINC interpolator

A FIR csinc interpolative filter design for bandpass signals is presented in this paper. The filter coefficients are calculated from the covariance of basis functions for the bandpass function space. They are invariant with respect to the samples of the input signals. The csinc model also works for low-pass signals as one of the design parameters approaches zero. The performance of the csinc filter is analyzed from the perspectives of accuracy, stability, and adaptation to noise in the samples. Comparisons are made between the csinc model and the existing interpolation models in the literature.