Abstrait

REVIEW OF DESIGNING FOR FRACTIONALORDER FRACTIONAL-DELAY DIGITAL FILTER

Jyoti Rathi , Rajiv Dahiya

Design and applications of fractional order digital differentiators is the main objective of this paper. Fractional order differentiators are examples of fractional order systems. In this paper, a brief survey of the design techniques of fractional delay digital differentiator is given. Fractional delay filter is a device for band limited interpolation between samples. It finds applications in numerous fields of signal processing, including communications, array processing, speech processing, and music technology. In this paper, we present a review of FIR and all pass filter design techniques for band limited approximation of a fractional digital delay. Emphasis is on simple and efficient methods that are well suited for fast coefficient update or continuous control of the delay value. Various new approaches are proposed and several examples are provided to illustrate the performance of the methods. We focus on four applications where fractional delay filers are needed: synchronization of digital modems, in commensurate sampling rate conversion, high-resolution pitch prediction, and sound synthesis of musical instruments.