Approaching the Outage Probability of the Amplify-and-Forward Relay Fading Channel

We study coding techniques for the single-relay non-orthogonal amplify-and-forward half-duplex relay fading channel. Unlike the multiple-antenna case, we show that 2times2 rotations induce large gains in outage probability with no increase in decoding complexity under iterative probabilistic decoding. We compare rotated and unrotated turbo-coded schemes and show that they both perform close to their corresponding outage limits.