Modular cascade structures for the designs of 1-D and 2-D variable fractional delay filters

Abstract

In this paper, modular cascade structures are presented to design one-dimensional (1-D) and two-dimensional (2-D) variable fractional delay (VFD) filters. First, a modular cascade structure for implementing 1-D VFD filter is obtained by using the infinite product expansion of exponential function. This structure is only composed of one basic modular cell. Then, the first order digital differentiator which is designed by the least squares method is applied to realize basic cell in the proposed structure. Next, the proposed method is extended to design 2-D VFD filter. Finally, several numerical examples are demonstrated to show the effectiveness of the proposed VFD filter structures and design methods.