... better For example, if the allpass VFD filter is designed again with p ∈ [−0.65, 0.35] for both LS design and minimax design, the absolute errors of group-delay for LS design and minimax design are ... [24] J J Shyu, S C Pei, and C H Chan, Minimax phase error design of allpass variable fractional-delay digital filters by iterative weighted least-squares method, ” Signal Processing, vol 89, no ... [11] J J Shyu, S C Pei, C H Chan, and Y D Huang, Minimax design of variable fractional-delay FIR digital filters by iterative weighted least-squares approach,” IEEE Signal Processing Letters, vol...