Viterbi Decoding Algorithm for Convolutional Codes with Repeat Request

Hirosuke YAMAMOTO and Kohji ITOH

IEEE Trans. on Information Theory, Vol.IT-26, No.5, pp.540-547, SEP. 1980)

  • Using the Viterbi decoding algorithm with repeat request for convolutional codes is proposed, and the resulting performance is analyzed by random coding and generating function arguments and by simulation. It is shown that the reliability function of the proposed decoding algorithm is asymptotically twice that of Viterbi decoding algorithm without repeat request,and that in certain practical situations the proposed algorithm can save about 50 percent in constraint length over the ordinary Viterbi algorithm for a given performance.

  • This scheme is explained in the following books:
  1. S. Lin and D. J. Costello, Jr., Error Control Coding: Fundamentals and Applications, Prentice Hall: Englewood Cliffs, NJ, 1983 (ISBN 0-13-283796-X)
  2. Ajay Dholakia, Introduction to Convolutional Codes with Applications, Kluwer Academic Publishers, 1994 (ISBN 0-7923-9467-4)
  3. L. L. Hanzo, J. Blogh, S. Ni, 3G, HSPA and FDD versus TDD Networking: Smart Antennas and Adaptive Modulation, John Wiley & Sons, 2008 (ISBN 978-0-470-75420-7)
  • This scheme is implemented in the Keystone Architecure Viterbi-Decoder Coprocessor (VCP2), Texas Instruments. Refer Section 2.3 "Yamamoto Parameters", Section 3.4 "VCP2 Input Configuration Register 1 (VCPIC1)", and Section 3.10 "VCP2 Output Register 1 (VCPOUT1)" in the manual (PDF) of the DSP.