Dual Fixed-Point: An Efficient Alternative to Floating-Point Computation

  • Chun Te Ewe
  • Peter Y. K. Cheung
  • George A. Constantinides
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3203)


This paper presents a new data representation known as Dual FiXed-point (DFX), which employs a single bit exponent to select two different fixed-point scalings. DFX provides a compromise between conventional fixed-point and floating-point representations. It has the implementation complexity similar to that of a fixed-point system together with the improved dynamic range offered by a floating-point system. The benefit of using DFX over both fixed-point and floating-point is demonstrated with an IIR filter implementation on a Xilinx Virtex II FPGA.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Chun Te Ewe
    • 1
  • Peter Y. K. Cheung
    • 1
  • George A. Constantinides
    • 1
  1. 1.Department of Electrical & Electronic EngineeringImperial CollegeLondonEngland

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