Weighted sum-rate based power allocation for the uplink of nonregenerative cooperative multi-user MIMO communication system

Amplify-and-forward (AF) is one of the most popular and simple approaches to transmit information over a cooperative multi-input multi-output (MIMO) relay channel. In this paper, we propose a novel power allocation method for the uplink of multi-user MIMO AF cooperative system, which is designed to optimise the weighted sum-rate of the cooperative system. This method provides similar sum-rate performance than algorithms that are designed to solely maximise the sum-rate of the system, and at the same time it increases the fairness of the rate distribution amongst the users. The performance of our method has been assessed against a sum-rate criterion based method, and results have shown clear improvement in terms of the fairness of the user rate distribution.