Iterative Antenna Selection for Decode-and-Forward MIMO Relay Systems Under a Holistic Power Model

In this letter, we investigate the antenna selection in decode-and-forward (DF) MIMO relay systems where the circuit power consumption is considered. The main problem is that the optimal active relay antenna subsets can only be selected by exhaustive search. To reduce the complexity, three iterative properties on the capacity bounds are first derived in this letter, which lay the foundation for our proposed algorithm. This algorithm can improve the performance of DF MIMO relay systems by the maximization of the upper and lower bounds on the capacity. Simulation results will show that the proposed low complexity algorithm has nearly the same performance as that of exhaustive search. In addition, it has a remarkable performance gain over the conventional DF MIMO relay protocol.