Phase improvement in IIR digital filters
S. Shi, MICHAEL T. MANRY · IEEE Transactions on Acoustics Speech and Signal Processing · 1989
A new technique is presented for improving the phase response of finite impulse-response (IIR) digital filters. In this technique, a measure of phase nonlinearity is developed. Given an IIR filter which has the desired amplitude response and it realized as a cascade of second-order sections, the measure is minimized by making some of the sections anticausal. Efficient implementation of this algorithm is discussed. Examples illustrating the technique are also given.>