Performance of hybrid ARQ schemes with ML code combining over a block-fading Rayleigh channel

Koorosh Akhavan, Shayan Farahvash, Mohsen Kavehrad

Research output: Contribution to journalArticlepeer-review

5 Scopus citations


This paper considers two well-known selective-repeat retransmission schemes, namely, hybrid type-I ARQ and hybrid type-II ARQ, using convolutional coding, in conjunction with maximum-likelihood code combining. Our theoretical analysis, based upon the concept of generalized weight distribution, shows that the use of code combining yields a significant throughput at very high channel error rates not only in constant AWGN channels but also in fading channels. To demonstrate this, we consider a widely-used block-fading Rayleigh channel model, in which the channel is assumed to be constant during each block of data and the fading is assumed to be independent from block to block. A key parameter in designing retransmission protocols for delay-limited applications in such channels is the minimum number of retransmissions, needed to achieve error-free decoding at almost all channel conditions (low outage probability). This number can be reduced significantly when code combining is employed.

Original languageEnglish (US)
Pages (from-to)1-8
Number of pages8
JournalInternational Journal of Wireless Information Networks
Issue number1
StatePublished - 2000

All Science Journal Classification (ASJC) codes

  • Hardware and Architecture
  • Computer Networks and Communications
  • Electrical and Electronic Engineering


Dive into the research topics of 'Performance of hybrid ARQ schemes with ML code combining over a block-fading Rayleigh channel'. Together they form a unique fingerprint.

Cite this