Maximizing Energy Efficiency in Heterogeneous Cellular Network with Massive MIMO and Small Cells

With the rapid development of wireless cellular network, massive multiple input and multiple output (MIMO) and Small Cells (SCs) are both suitable candidates for the future fifth generation (5G) networks. Energy Efficiency (EE) has become increasingly concerned along with the two powerhungry candidates. This paper herein analyzed the energy efficiency of heterogeneous cellular network with massive MIMO and SCs. We maximized the EE by assigning the antennas of macro base station and SCs. We studied the relationship among the macro base station antennas, SCs and users by simulation and curve-fitting. Due to the fact that the Minimum Mean Square Error (MMSE) algorithm has better performance than the convex operation for total power minimization, we chose the MMSE algorithm to acquire the maximum energy efficiency with different amount of macro base station antennas, SCs and users. From the numerous simulation results, it can be seen that the number of antennas in the macro base station, the number of SCs and the user numbers have linear relationship when EE reaches the maximum value.