Transmit/Receive Beamforming in Multiuser AF Relay Networks with Opportunistic Scheduling

This paper evaluates the outage performance of multiuser relay networks in which the source and each one of the destinations are equipped with multiple antennas and employ beamforming techniques. More specifically, assuming Rayleigh fading channels and an amplify-and-forward relay, a general closed-form expression for the end-to-end outage probability is derived. Our analysis takes into account the benefits conferred by opportunistic scheduling in relay-assisted networks, where the source selects the destination with the strongest channel to schedule data transmission. The analytical results are validated by means of Monte Carlo simulation, and the effects of the relay placement and antenna configurations, on the overall system performance, are discussed through some representative numerical results and comparisons.