Hardware and Spectrum Sharing for Distributed Massive MIMO

Massive MIMO promises unprecedented spectral efficiency as values exceeding 140 b/s/Hz have already been demonstrated in the lab for a single cell. In this paper, based on measurements obtained in a distributed Massive MIMO testbed, we compare the spectral efficiency, area spectral efficiency, and capacity of two adjacent cells under different levels of cooperation and the impact of co-channel interference. This is the first Massive MIMO measurement based analysis of the performance of spectrum and infrastructure sharing, showing that in fully cooperative systems (sharing infrastructure and spectrum) there is an improvement of the area spectral efficiency by 50% and a sixfold of capacity in comparison with a scenario without sharing, i.e. conventional two-cells planning. In comparison to the scenario where only spectrum is shared, the infrastructure and spectrum sharing case also increases the area spectral efficiency by two and the overall capacity by four. In addition, the use of M-MMSE increases the performance of the system in 43% in relation to RZF, for this particular scenario when co-channel interference is considered.