Advertisement

Catastrophicity Test for Time-Varying Convolutional Encoders

  • Conor O’Donoghue
  • Cyril Burkley
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1746)

Abstract

A new catastrophicity test for convolutional encoders whose rate and generator polynomials vary with time is presented. Based on this test computationally efficient algorithm to determine whether or not a time-varying convolutional encoder is catastrophic is derived. This algorithm is shown to be simpler than the catastrophicity test proposed by Balakirsky [1]. Furthermore, the algorithm can easily be generalised to rate k/n time-varying convolutional encoders.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    V.B. Balakirsky, “A necessary and su_cient condition for time-variant convolutional encoders to be noncatastrophic,” Lecture Notes in Computer Science, No. 781, pp. 1–10, Springer-Verlag, 1993.Google Scholar
  2. 2.
    J.L. Massey and M.K. Sain, “Inverses of linear sequential circuits,” IEEE Trans. Computers, Vol. C-17,No. 4, pp. 330–337, April 1968.CrossRefGoogle Scholar
  3. 3.
    R.R. Olsen, “Note on feedforward inverses for linear sequential circuits,” IEEE Trans. Computers, Vol. C-19,No. 12, pp. 1216–1221, Dec. 1970.CrossRefGoogle Scholar
  4. 4.
    G.D. Forney, Jr., “Minimal bases of rational vector spaces, with applications to multivariable linear systems,” SIAM J. Control, vol. 13, pp.493–520, May 1975.zbMATHCrossRefMathSciNetGoogle Scholar
  5. 5.
    R. Johannesson and Z.-X. Wan, “A linear algebra approach to convolutional encoders,” IEEE Trans. Inform. Theory, vol. IT-39,No. 4, pp. 1219–1233, July 1993.CrossRefMathSciNetGoogle Scholar
  6. 6.
    P.J. Lee, “There are many good time-varying convolutional codes,” IEEE Trans. Inform. Theory, Vol. IT-35,No. 2, pp. 460–463, March 1989.CrossRefGoogle Scholar
  7. 7.
    M. Mooser, “Some periodic convolutional codes better than any fixed code,” IEEE Trans. Inform. Theory, Vol. IT-29,No. 5, pp. 750–751, Sept. 1983.CrossRefGoogle Scholar
  8. 8.
    R. Palazzo, “A time-varying convolutional encoder better than the best time-invariant encoder,” IEEE Trans. Inform. Theory, Vol IT-39,No.3, pp. 1109–1110, May 1993.CrossRefMathSciNetGoogle Scholar
  9. 9.
    C. O’Donoghue, and C.J. Burkley, “Minimality and canonicity tests for rational generator matrices for convolutional codes,” in Proc. 1998 IEEE Information Theory Workshop, pp. 112–114, Killarney, 22-26 June, 1998.Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1999

Authors and Affiliations

  • Conor O’Donoghue
    • 1
  • Cyril Burkley
    • 2
  1. 1.Silicon & Software SystemsDublinIreland
  2. 2.Dept. of Electronic EngineeringUniversity of LimerickLimerickIreland

Personalised recommendations