Distributed turbo coding using log-likelihood thresholding for cooperative communications

Ghaleb Al-Habian, Ali Ghrayeb, Mazen Hasna, Adnan Abu-Dayya

Research output: Chapter in Book/Report/Conference proceedingConference contribution

5 Citations (Scopus)

Abstract

In cooperative communications, error propagation at relays reduces the diversity order of the system. To combat that effect, we present a novel technique to control error propagation at the relays, which is presented in the context of a relay cooperating with a source to communicate with a destination using a turbo code. The relay calculates log-likelihood ratio (LLR) values for the bits sent from the source. These value are subjected to a threshold to selectively forward bits that are most reliable and discard bits that are less so, resulting in less errors propagating to the destination. We derive upper bounds on the bit-error rates for our proposed system and use them to optimize the threshold at the relay, showing that our system provides a better trade off between prevented errors and blocked correct bits. We compare our scheme with controlling error propagation using only a cyclic redundancy code(CRC) check at the relay, forwarding analog LLR values, and employing no error control at the relay at all. Based on system simulations, we show that our proposed scheme provides a significant diversity gain compared to other techniques.

Original languageEnglish
Title of host publication2008 42nd Asilomar Conference on Signals, Systems and Computers, ASILOMAR 2008
Pages1005-1009
Number of pages5
DOIs
Publication statusPublished - 1 Dec 2008
Event2008 42nd Asilomar Conference on Signals, Systems and Computers, ASILOMAR 2008 - Pacific Grove, CA, United States
Duration: 26 Oct 200829 Oct 2008

Publication series

NameConference Record - Asilomar Conference on Signals, Systems and Computers
ISSN (Print)1058-6393

Other

Other2008 42nd Asilomar Conference on Signals, Systems and Computers, ASILOMAR 2008
CountryUnited States
CityPacific Grove, CA
Period26/10/0829/10/08

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ASJC Scopus subject areas

  • Signal Processing
  • Computer Networks and Communications

Cite this

Al-Habian, G., Ghrayeb, A., Hasna, M., & Abu-Dayya, A. (2008). Distributed turbo coding using log-likelihood thresholding for cooperative communications. In 2008 42nd Asilomar Conference on Signals, Systems and Computers, ASILOMAR 2008 (pp. 1005-1009). [5074563] (Conference Record - Asilomar Conference on Signals, Systems and Computers). https://doi.org/10.1109/ACSSC.2008.5074563