An enhanced multi-user eigen transmission scheme for cell-edge performance improvement

The multi-user eigen transmission (MET) scheme has been extensively investigated in multi-user multiple-input multiple-output (MU-MIMO) downlink transmission due to its remarkable performance at low computational complexity. Based on the existing solutions of MET discussed in open literatures, we propose an enhanced MET (eMET) scheme in this paper in order to further enhance the performance of cellular network in terms of spectral efficiency, especially for the cell-edge users. The theoretical analysis shows that by employing the successive transmit eigen-channel optimization and selection, the eMET scheme outperforms the classic MET approach in multi-cell downlink transmission. In parallel, Our system-level simulation results demonstrate that our proposed scheme outperforms its counterpart in both cell average and cell edge performance. Specifically, upon taking the performance of MET method as the baseline, the eMET regime can achieve over 15% spectral efficiency (SE) gain for cell edge users in single-cell (SC) transmission and over 30% SE gain in coordinated multi-point transmission (CoMP) without any loss of the system´s average performance.