A fair MU-MIMO scheme for IEEE 802.11ac

The next generation of wireless local area networks (WLANs), currently standardized within IEEE 802.11ac, will surely adopt multiuser multiple-input multiple-output (MU-MIMO) technology. This paper addresses the design of a multiuser proportional fair scheduling scheme, based on MU-MIMO orthogonal frequency division multiplexing (OFDM), that is able to schedule simultaneous transmissions to various users while providing a high degree of fairness. The proposed scheme is complemented by a fast link adaptation (FLA) strategy that, in light of the available channel state information (CSI), determines the most appropriate transmission parameters for each selected user. Simulation results generated using specifications envisaged for IEEE 802.11ac demonstrate the gains offered by the proposed technique with practical modulation and coding schemes.