On the diversity analysis of decode-and-forward protocol with multiple antennas

In this paper, a near maximum-likelihood (ML) decoder for orthogonal decode-and-forward (ODF) protocol with multiple antennas is proposed and the upper bound on the average pairwise error probability (PEP) for large signal to noise ratio is also derived, regardless of the modulation scheme. From the upper bound on the average PEP, we show that the ODF protocol with near ML decoder can achieve full diversity M<inf>S</inf>M<inf>D</inf>+M<inf>R</inf> min(M<inf>S</inf>;M<inf>D</inf>) for a cooperative network consisting of one source, one relay, and one destination with M<inf>S</inf>, M<inf>R</inf>, and M<inf>D</inf> antennas, respectively.