Energy-Efficient Massive MIMO for Future Generation Wireless Communication Systems

Abstract

Massive MIMO systems are an emerging technology to support enhanced energy and spectral efficiency in next-generation wireless systems. In this chapter, we have enhanced the energy efficiency of Massive MU-MIMO systems by utilizing a suitable precoding scheme and proper selection of several base-station antennas and user terminals in the cell. We simulated our results with minimum mean square error (MMSE), maximal ratio combining and transmission (MRC/MRT), zero-forcing (ZF) combining, and precoding schemes. The joint downlink and uplink transmissions are considered with several processing methods at the transmitter. We present an improved design for power consumption to analyze the results that show how several users, antennas at BS, and power transmitted can affect the energy efficiency of Massive MIMO systems. We derived expressions to evaluate energy efficiency under the consideration of ZF, MMSE, and maximal ratio (MR) processing methods. Simulation results depicted that maximum energy-efficiency points are obtained by a Massive MIMO system, where hundreds of antenna elements provide service to many user terminals utilizing ZF precoding and combining schemes. The results are investigated in single-cell and multicell environments.