The viability of distributed antennas for massive MIMO systems

Massive multiple-input multiple-output (MIMO) is a breakthrough communication technique for providing high spectral efficiency. The idea is to deploy a very large number of antennas at each base station and to use multiuser MIMO transmission to serve a smaller number of users. In this paper, the viability of using distributed antennas for massive MIMO on the uplink is investigated for a particular spatial correlation channel model. Both maximal ratio combining (MRC) and minimum mean squared error (MMSE) beamforming are found to provide higher performance in several distributed settings. An algorithm for remote radio head selection is proposed that allows MRC to approach the performance achieved by the MMSE beamforming solution yet retaining its lower complexity.