Massive MIMO Channel Performance Analysis Considering Separation of Simultaneous Users

One of the key aspects of massive MIMO
(mMIMO) is its ability to spatially differentiate between multiple
simultaneous users. The spatial separability improves as the
number of base station (BS) antenna elements is increased. In
real BS deployments, the number of BS array elements will be
fixed, and expected to provide the required service to a certain
number of simultaneous users in the existing propagation
environment. The mMIMO performance is investigated in this
paper, in an urban macro-cell scenario, using three kinds of
channel models with different complexity levels: the independent
and identically distributed Rayleigh fading model, a geometrybased
stochastic model, and a physical ray-based software. Two
performance indicators are analyzed: the favorable propagation
metric and the multi-user eigenvalue distribution. Two
frequencies (2 GHz and 28 GHz) and two antenna array shapes
(linear and circular) are considered and compared.