SNR decomposition for full-duplex Gaussian relay channel

Zhengchuan Chen, Pingyi Fan, Khaled Letaief

Research output: Contribution to journalArticle

10 Citations (Scopus)


A relay channel (RC), consisting of a source, a relay, and a destination, is a basic transmission unit of cooperative communication networks. The capacity of an RC is not known in general. In this paper, an SNR decomposition (SD) strategy is presented to implement time sharing, which provides a new tractable and achievable rate for a full-duplex Gaussian RC. More specifically, we first expand the SNR of a relay destination channel (SNR-RD) into two terms under the relay power constraint and divide the system into two subbands. Then, we assign the obtained SNR-RD for each subband and employ decode-forward (DF) or compress-forward (CF) according to the assigned SNR-RD. It is shown that the achievable rate of the SD strategy is competitive with that of superposing CF on DF. As the superposition structure requires a sophisticated codeword design, the SD strategy provides another practical combination structure of DF and CF strategies. Approximations for the SNR-RD and bandwidth allocation for subbands are also given. Based on the obtained results, two application scenarios, i.e., mobile relay and quasi-static fading RCs, are also considered. Finally, various numerical results are shown to support our developed theoretical results.

Original languageEnglish
Article number6915763
Pages (from-to)841-853
Number of pages13
JournalIEEE Transactions on Wireless Communications
Issue number2
Publication statusPublished - 2015
Externally publishedYes



  • Compress-Forward (CF)
  • Decode-Forward (DF)
  • Gaussian relay channel
  • SNR Decomposition (SD)

ASJC Scopus subject areas

  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

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