Decode-compress and forward relay: AWGN and constellation constrained channels
Ahmed Attia Abotabl, Aria Nosratinia · 2017
Even though there exists a lot of different transmission techniques, the capacity of the general relay channel is still unknown. This paper shows that combining decode-and-forward (DF) with compress-and-forward (CF) can have a performance advantage over each of the two techniques individually. Combining the two techniques goes back to the celebrated work of Cover and El-Gamal [1], more specifically, they gave an achievable rate for the DF-CF combination. In this paper, we re-derive the achievable rate of combining DF with CF in the full-duplex discrete memoryless relay channel. We derive the achievable rate in the AWGN relay channel as well as the constrained constellation AWGN relay channel. We show that even though in the AWGN channel, DF-CF combination does not provide any advantage, under constrained constellation, combining the two techniques has an advantage.