  This paper investigates the spectral efficiency (SE) of multi-cell Massive
Multi-Input Multi-Output (MIMO) using different channel models. Prior works
have derived closed-form SE bounds and approximations for Gaussian distributed
channels, while we consider the double scattering model-a prime example of a
non-Gaussian channel for which it is intractable to obtain closed form SE
expressions. The channels are estimated using limited resources, which gives
rise to pilot contamination, and the estimates are used for linear detection
and to compute the SE numerically. Analytical and numerical examples are used
to describe the key behaviors of the double scattering models, which differ
from conventional Massive MIMO models. Finally, we provide multi-cell
simulation results that compare the double scattering model with uncorrelated
Rayleigh fading and explain under what conditions we can expect to achieve
similar SEs.
