Diversity-multiplexing tradeoff for the non-separated two-way relay DF channel

Arun Kumar Singh (1) , Petros Elia (2) , Kiran T Gowda (1) , David Gesbert (1)

1 Eurecom [Sophia Antipolis]
2 Mobile communications

This work establishes the diversity-multiplexing tradeoff (DMT) of the four-phase decode-and-forward (DF) protocol in the half-duplex, non-separated two-way relay channel. We consider a fading channel model where the source relay links are Rayleigh distributed but the direct link between sources is left more general as Nakagami-m distributed and investigate for any possible gains in the achievable DMT using four-phase hybrid broadcast (HBC) protocol, as compared to three-phase time-division broadcast (TDBC) protocol. For the statistically symmetric case of Rayleigh fading and asymmetric fading with more stable direct link (m >; 1), the optimal DMT of the HBC protocol is computed, and is shown to be achieved by a three-phase orthogonal variant, TDBC protocol. The operational meaning of this result is that the multiple access channel (MAC) phase of HBC protocol is not necessary to achieve optimal performance, this results in a simplification of the communication protocol. For less stable direct link (1/2 ≤ m <; 1), the analysis establishes that the MAC phase of HBC protocol is necessary to achieve optimal DMT.

Domaines: Théorie de l'information et codage [math.IT]; Théorie de l'information [cs.IT]

Arun Kumar Singh, Petros Elia, Kiran T Gowda, David Gesbert. Diversity-multiplexing tradeoff for the non-separated two-way relay DF channel. 2011 IEEE 12th International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), Jun 2011, United States. pp.196 - 200, ⟨10.1109/SPAWC.2011.5990393⟩. ⟨hal-00707802⟩