Design of minimum noise digital filters subject to inequality constraints using quadratic programming
James T. Lewis, R. Murphy, D.W. Tufts · IEEE Transactions on Acoustics Speech and Signal Processing · 1976
A numerical method is presented for designing digital filters. The method allows one to minimize the mean-square error or noise power over some intervals of frequency, while simultaneously constraining the maximum error in other intervals of frequency. Thus, for example, one can minimize noise power from a stopband of frequencies while constraining signal fidelity in a passband of frequencies by limiting the maximum passband deviation.