On the performance of MIMO Af system with incremental relaying

Cooperative relaying has shown as promising approach to provide spatial transmit diversity gains and potentially increase capacity. In this paper, we consider an incremental relaying protocol. This protocol uses feedback from the destination to transmitters to choose between direct transmission or cooperation. In this study we show that the incremental protocol is beneficial for MIMO system under the amplify and forward (AF) model. The lower bounds for the BER are obtained using the moment generating function (MGF) approach by evaluating the MGF of the end-to-end equivalent signal to noise ratio (SNR) of the system. Simulations demonstrate that the proposed protocol can substantially improve the performance of the system comparing to the non-cooperative scheme.