Design of phase equalizers for recursive filters
A. Antoniou, R. K. Howell · 2002
A least-pth optimization method for the design of an allpass filter to act as a phase equalizer for a given recursive filter is described. The method is applied to various elliptic filters, and the combined filter/equalizer designs are compared with corresponding nonrecursive designs. An optimum equalizer-filter combination can be obtained by selecting a filter with a small passband ripple in the amplitude response. Overall, an equalized design requires substantially fewer filter coefficients, typically 15 to 75% less, than a corresponding nonrecursive design obtained using the Remez exchange algorithm.>