Effect of feedback delay on dual‐hop fixed gain relay networks over mixed fading channels
Min Lin, Kang An, Jian Ouyang, Heng Wei, Jun-hong Dang · Transactions on Emerging Telecommunications Technologies · 2013
ABSTRACT In this paper, we investigate the effect of feedback delay on a dual‐hop fixed gain amplify‐and‐forward relay network over Rayleigh–Rician mixed fading channels, where the source and destination are all equipped with multiple antennas, while the relay has a single antenna. By using the model of beamforming with feedback delay, the equivalent output signal‐to‐noise ratio (SNR) of the amplify‐and‐forward relay network is first obtained. Then, based on the infinite series representation, the analytical expressions for the outage probability and the probability density function of the output SNR are derived. Furthermore, the analytical formulas of the ergodic capacity and the average symbol error rate formulas with various modulation formats are developed. To reveal the diversity order and array gain of the multi‐antenna relay network, the asymptotic average symbol error rates at high SNR are also presented. Finally, computer simulations are provided to validate the theoretical analysis and to indicate the effect of antenna number, feedback delay and channel parameters on the system performance. Copyright © 2013 John Wiley & Sons, Ltd.