Asymptotic SEP of MIMO beamforming in two-hop AF relaying systems

This paper derives an asymptotic average symbol error probability (SEP) expression for multipleinput multiple-output (MIMO) two-hop amplify-and-forward (AF) relay systems with optimal beamforming. The analysis at high signal-to-noise ratio (SNR) quantifies the diversity order and array gain, which are valid for any antenna numbers of the terminals and arbitrary channel fading models. It is also proved that the system performance is dominated by the relatively degraded one of the two-hop channels. Our results based on the simple expressions provide valuable insights into the performance and practical design considerations of MIMO AF networks.