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High radix cordic rotation based on selection by rounding

  • E. Antelo
  • J. D. Bruguera
  • T. Lang
  • J. Villalba
  • E. L. Zapata
Workshop 08+09+10 Parallel Image/Video Processing and Computer Arithmetic
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1124)

Abstract

We present a high-radix Cordic rotation algorithm, which results in a reduction of the number of iterations. Carry-save representation is used and the selection function is performed by rounding, except for i=0 where a small table is necessary. The scale factor is not constant, but is efficiently computed in logarithmic form and compensated by a high radix exponential algorithm, where again we use selection by rounding. The algorithm proposed assures convergence for radices up to 1024. An architecture is presented and the execution time evaluated. A comparison with a radix-2 implementation demonstrates the speed-up achieved by the high-radix approach.

Index terms

CORDIC algorithm Rotation mode High radix algorithm 

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Copyright information

© Springer-Verlag Berlin Heidelberg 1996

Authors and Affiliations

  • E. Antelo
    • 1
  • J. D. Bruguera
    • 1
  • T. Lang
    • 2
  • J. Villalba
    • 3
  • E. L. Zapata
    • 3
  1. 1.Dept. Electrónica y ComputaciónUniversidad Santiago de CompostelaSpain
  2. 2.Dept. of Electrical and Computer Eng.University of California at IrvineUSA
  3. 3.Dept. Computer ArchitectureUniversity of MálagaSpain

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