Energy Efficient Multiple Access Scheme for Multi-User MIMO-OFDM System with Improved Gain

In this paper, to improve the energy efficiency (EE) of multi-user multiple-input multiple-output (MIMO) orthogonal frequency-division multiple access (OFDMA) system, an Energy-efficient multiple access (EMA) scheme is proposed. It improves EE by selecting either time-division multiple access (TDMA) or space-division multiple access (SDMA) based on the no. of users or power consumption. Here, we introduced normalization process for power in OFDM system to improve the power gain. Numerical results verify that the EE and power gain can be significantly improved through the proposed EMA scheme.