Trade-Off Energy and Spectral Efficiency in a Downlink Massive MIMO System

Abstract

Massive multiple-input multiple-output (MIMO) technology has been proven to be a viable strategy for balancing the trade-off between energy efficiency (EE) and spectral efficiency (SE), which is key to the design of fifth-generation wireless cellular networks. In this work, we investigate the trade-off between EE and SE for downlink massive MIMO in wireless communication networks with respect to the power allocation problem. We maximize EE by deriving the signal-to-interference noise ratio for higher SE in the upper bound and propose that the EE–SE trade-off can be maximized when formulated as a Pareto-optimal solution based on the optimization problem. A Lagrange dual decomposition method is also developed for both transmit power allocation and the number of available antennas. From the simulation results, the maximum trade-off between EE and SE can be achieved based on the optimal transmit power allocation in every cell and when the number of base stations for the value of SE is high.