Design of equiripple log FIR and IIR filters using multiple exchange algorithm

In this paper, an efficient design method for linear phase FIR filter with equiripple log magnitude response is first
investigated. Then, we extend this method to design a class of IIR filter having equiripple behavior in both log magnitude
and group delay response. Both design procedures are mainly based on the multiple exchange algorithm. Also, the log
FIR and IIR filters are designed in three cases where the passband and stopband error ratio, or the passband error, or the
stopband error are specified. Several design examples for lowpass log filters are presented to demonstrate the effectiveness
of the proposed methods.