Leakage-based power allocation for relaxed SLNR beamforming in multi-cell MU-MIMO systems

In this paper, we propose a power allocation scheme to suppress the inter-cell interference (ICI) in multi-cell multiuser multiple-input-multiple-output (MU-MIMO) systems. In particu-lar, by adopting relaxed signal-to-leakage-and-noise ratio (SLNR) beamforming, the transmit power allocated to the user is linearly associated with the leakage, which differs from previous works. Furthermore, we obtain the closed-form lower bound on the achieved sum rate with minimum mean-squared error (MMSE) detection at receivers, which is semi-analytical and numerically evaluatable. Simulation results demonstrate that our scheme can obtain a significant sum rate improvement while maintain a similar bit error rate (BER) performance compared with the conventional ones.