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Floating-to-Fixed-Point Conversion for Digital Signal Processors

EURASIP Journal on Advances in Signal Processing volume 2006, Article number: 096421 (2006) Cite this article

Abstract

Digital signal processing applications are specified with floating-point data types but they are usually implemented in embedded systems with fixed-point arithmetic to minimise cost and power consumption. Thus, methodologies which establish automatically the fixed-point specification are required to reduce the application time-to-market. In this paper, a new methodology for the floating-to-fixed point conversion is proposed for software implementations. The aim of our approach is to determine the fixed-point specification which minimises the code execution time for a given accuracy constraint. Compared to previous methodologies, our approach takes into account the DSP architecture to optimise the fixed-point formats and the floating-to-fixed-point conversion process is coupled with the code generation process. The fixed-point data types and the position of the scaling operations are optimised to reduce the code execution time. To evaluate the fixed-point computation accuracy, an analytical approach is used to reduce the optimisation time compared to the existing methods based on simulation. The methodology stages are described and several experiment results are presented to underline the efficiency of this approach.

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Authors and Affiliations

  1. R2D2 Team (IRISA), ENSSAT, University of Rennes I, 6 rue de Kerampont, Lannion, 22300, France

    Daniel Menard, Daniel Chillet & Olivier Sentieys

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  1. Daniel Menard
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  2. Daniel Chillet
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  3. Olivier Sentieys
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Correspondence to Daniel Menard.

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Open Access This article is distributed under the terms of the Creative Commons Attribution 2.0 International License ( https://creativecommons.org/licenses/by/2.0 ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Menard, D., Chillet, D. & Sentieys, O. Floating-to-Fixed-Point Conversion for Digital Signal Processors. EURASIP J. Adv. Signal Process. 2006, 096421 (2006). https://doi.org/10.1155/ASP/2006/96421

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