Energy efficiency of single cell and multi cell Massive MIMO system MMSE estimation

Multi input multi output (MIMO) has become a promising technique for 5th generation cellular network. By significantly increasing the number of antennas at the Base Station (BS) Massive MIMO can support very high spectral efficiency with linear transceivers. Energy efficiency is one of the critical design goal for 5G network. The aim of this paper is to analyze the energy efficiency of single cell and multi cell Massive MIMO, where transmit and circuit power consumption, training overhead, channel estimation, pilot contamination and decontamination is taken into account. Maximal energy efficiency for the system is obtained by using Maximum Ratio Transmission (MRT) for given number of antennas and users by optimizing the transmit power. A multi cell Massive MIMO suffers from pilot contamination due to unavoidable reuse of pilots in adjacent cells. Pilot contamination causes inter cell interferences, which grows as the number of Base Station (BS) antennas increases and damages the system performance.