Table of Contents
VLSI Design
Volume 2014, Article ID 690594, 13 pages
Research Article

Radix-2α/4β Building Blocks for Efficient VLSI’s Higher Radices Butterflies Implementation

Laboratory of Signals and Systems Integrations, Electrical and Computer Engineering Department, Université du Québec à Trois-Rivières, QC, Canada G9A 5H7

Received 27 December 2013; Revised 12 March 2014; Accepted 26 March 2014; Published 13 May 2014

Academic Editor: Dionysios Reisis

Copyright © 2014 Marwan A. Jaber and Daniel Massicotte. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


This paper describes an embedded FFT processor where the higher radices butterflies maintain one complex multiplier in its critical path. Based on the concept of a radix-r fast Fourier factorization and based on the FFT parallel processing, we introduce a new concept of a radix-r Fast Fourier Transform in which the concept of the radix-r butterfly computation has been formulated as the combination of radix-2α/4β butterflies implemented in parallel. By doing so, the VLSI butterfly implementation for higher radices would be feasible since it maintains approximately the same complexity of the radix-2/4 butterfly which is obtained by block building of the radix-2/4 modules. The block building process is achieved by duplicating the block circuit diagram of the radix-2/4 module that is materialized by means of a feed-back network which will reuse the block circuit diagram of the radix-2/4 module.