S. Samadi et H. Iwakura, VARIABLE TAYLOR REALIZATION AND IMPROVED APPROXIMATION OF FIR FRACTIONAL DELAY SYSTEMS, International journal of circuit theory and applications, 26(5), 1998, pp. 513-522
A modular realization, based on the Taylor structure, is proposed for
maximally hat fractional delay FIR systems. The realization enjoys ind
ependence of the multiplier coefficients to changes of the system orde
r, availability of closed-form formulas and recurrence for the multipl
ier coefficients, requirement of one less multiplier coefficient compa
red to the direct-form realizations, and existence of schemes for effi
cient variable delay and order implementations. It is shown that for a
variable delay structure, the coefficient updating operation can be p
erformed efficiently using a simple recurrence, and the transient effe
cts can be mitigated to at most two samples. A modified form of the st
ructure with enhanced modularity is also proposed for odd-order system
s. Two variable delay schemes are proposed for this modified structure
: A transient-free scheme and a scheme to gradually improve the approx
imations during the transient phase. A method is also proposed for imp
roved approximation under a fixed total number of variable multiplier
coefficients. (C) 1998 John Wiley & Sons, Ltd.