Near-optimal low-complexity antenna selection scheme for energy-efficient correlated distributed MIMO systems

A distributed multiple-input multiple-output (D-MIMO) system is a promising candidate for future wireless communications with significantly enhanced spectral and energy efficiency. For high data rate systems equipped with a large number of antennas, which cause a spatial antenna correlation, there is a strong motivation to develop schemes for achieving high energy efficiency and low computational complexity, while supporting high capacity. This paper proposes an effective near-optimal antenna selection algorithm with low complexity for correlated D-MIMO systems. The proposed algorithm begins with an antenna with the highest channel gain and adds the best antennas supporting the highest level of uncorrelation with the maximum channel gain in each step. Compared to the conventional algorithms via computer simulations, the proposed scheme achieved similar capacity to the optimal selection algorithms but with reduced hardware cost and complexity in several D-MIMO configurations with even highly correlated antennas. In particular, the performance gain of this scheme became significant when a small number of the best antennas were selected, resulting in high energy efficiency in D-MIMO systems.