Comparison of the MRT and ZF Precoding in Massive MIMO Systems from Energy Efficiency Viewpoint

In this paper, the performance of a massive multiple input multiple output (MIMO) system in terms of energy efficiency (EE) is evaluated. Two scenarios are investigated with two different algorithms. In the first proposed solution method, the maximum ratio transmission (MRT) receiver is employed. It is possible to balance the complexity of signal reception and system performance by using the MRT precoding scheme. In the second proposed method, the zero forcing (ZF) receiver is used, which have less complexity in telecommunication systems. The desired problem of maximizing EE is formulated and both solutions are examined. The first method utilizes the Hessain matrix and obtains the power of each user, while the second method uses the Lagrange dual function to get the proper power values of users. Two specific algorithms are presented in two proposed schemes to find the optimal power for each user, which maximizes the EE of the system. Computer simulation results are used to show the performance of two precoding methods. Based on the results, one can achieve better EE performance for each user in the MIMO systems.