A low complexity user selection scheme in downlink MU-MIMO system

In this paper, we describe a low complexity greedy user selection scheme for multiuser MIMO systems. We propose a new metric which has significantly reduced computational complexity and improved performance compared to Frobenius norm. The approximation of projection matrix is applied to reduce the number of singular value decomposition (SVD) operations. We analyze the computational complexity of metrics, and verify the reduced complexity by numerical evaluation. Our simulation result shows that the proposed metric can achieve the improved sum rate as the number of user antenna increases.