Performance analysis of amplify-and-forward cooperative communication systems with channel estimation errors

Cooperative diversity is a transmission technique that achieves a diversity gain by using a combination of the relayed signal and the direct signal. In this paper, we study the symbol-error-rate (SER) performance of a cooperative communication system operating in an amplify-and-forward (AF) mode, where the channel state information (CSI) available at the receiver is an estimate of the channel gains with estimation errors. We derive both the probability density function and the moment generating function of the instantaneous signal-to-noise ratio (SNR) at the destination terminal. These statistical quantities are then applied to study the performance of an AF cooperative communication systems. More precisely, an accurate SER expression for AF cooperative communication systems with channel estimation errors is obtained. This result encompasses the performance of AF cooperative communication systems with perfect CSI as a special case. Furthermore, simulation results are presented to verify the correctness of the analytical solutions.