Performance analysis of opportunistic beamforming system under non‐identical imperfect channel environment

Abstract

In this study, the authors study the effect of non-identical channel estimation error and feedback delay on the performance of an opportunistic beamforming system. This study derives the exact system performance (i.e. outage probability, symbol-error rate (SER), and ergodic capacity) of the proposed system using moment generating function in an imperfect channel environment. This study also uses an asymptotic analysis to quantify the diversity order of SER and outage probability to analyse which system variables affect system performance. From the results of an asymptotic analysis, it is shown that by channel estimation error and feedback delay, spatial diversity is eliminated, but the benefits of multiuser diversity still exist. Therefore, the diversity order of the SER and the outage probability of the proposed system are proportional to the number of user terminals, but the conventional system is limited to 1 by channel estimation error and feedback delay.