On the approximation problem for recursive digital filters with arbitary attenuation curve in the pass-band and the stop-band
H. Dubois, Henri Leich · IEEE Transactions on Acoustics Speech and Signal Processing · 1975
The approximation of attenuation curve for a recursive digital filter is solved for arbitrary specifications in the stop-band and in the pass-band. The problem is split into two parts; the first one uses the classical theory of the transformed plane and the second one works with linear programming. The method is illustrated by some specific examples.