Title: Design of first-order differentiator utilising FIR and IIR sub-filters

Authors: Ljiljana D. Milić; Miroslav D. Lutovac; Jelena D. Ćertić

Addresses: Faculty of Electrical Engineering, University of Belgrade, Belgrade, Serbia ' Faculty of Business, Singidunum University, Belgrade, Serbia ' Telecommunications Department, Faculty of Electrical Engineering, University of Belgrade, Belgrade, Serbia

Abstract: In this paper, we propose a novel approach for constructing the first-order differentiator. It has been shown recently that an efficient Finite Impulse Response (FIR) wideband differentiator can be synthesised when applying the multirate and Frequency-Response Masking (FRM) techniques. The overall signal processing task is shared between a very low-order differentiator and an FIR half-band filter. The novelty of this paper is the usage of an approximately linear-phase IIR half-band filter based on the parallel connection of all-pass sub-filter and pure delay. The structure of resulting wideband differentiator consists of the approximately linear phase all-pass sub-filter, two low-order FIR polyphase sub-filters, and the delay element. The knowledge-based design has been used for the analysis and improvements of the wideband differentiator. The proposed system provides computational savings and exhibits a significantly smaller overall delay if compared with the corresponding solution based on FIR filters only.

Keywords: all-pass filters; approximately linear phase IIR filter; FIR wideband differentiators; half-band filters; multirate filtering; finite impulse response; signal processing; first-order differentiator design.

DOI: 10.1504/IJRIS.2013.055122

International Journal of Reasoning-based Intelligent Systems, 2013 Vol.5 No.1, pp.3 - 11

Published online: 17 Jul 2013 *

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