Ideal Fractional Delay

Continuous time-delay filters are continuous all-pass filters whose Laplace transform is . Extension of time-delay filters to discrete filters leads, when the delay p is integer, to a basic delay line whose z-transform is . When the delay is not an integer, a fractional delay digital filter (FDDF) can be introduced as an ideal filter.

 
• From Continuous to Discrete
• An Ideal Transfer Function
• Analytical Approximations