Obtaining bandpass filter coefficients from low-pass prototypes
C.J. Alajajian · Proceedings of the IEEE · 1986
In this letter a method is given for calculating the transfer function coefficients of an analog bandpass filter stemming from a known, all-pole low-pass prototype, which is independent of the filter order. By posing the problem as an interpolation problem and choosing uniformly spaced interpolating points On the unit circle, the coefficients are computed efficiently and accurately via the discrete Fourier transfrom.