Beamforming in dual-hop fixed gain relay systems with antenna correlation

Abstract

The impact of antenna correlation on the performance of beamforming in a dual-hop fixed gain amplifyand-forward (AF) relay network is analyzed. The source and destination nodes are equipped with multiple antennas correlated in space, whereas the relay has a single antenna. Closed-form expressions for the system's outage probability and the average bit error rate (BER) are derived. We have also presented simple asymptotic outage probability and average BER expressions. When the second link is much stronger than the first link, it is shown that the system's performance at high SNR is only governed by the spatial correlation and number of antennas at the source and the diversity order is equal to the number of antennas at the source. Our analytical results have been verified through comparison with Monte Carlo simulations. ©2010 IEEE.