Abstract
In this paper, a novel spatially non-stationary fading channel model is
proposed for multiple-input multiple-output (MIMO) system with extremely-large
aperture service-array (ELAA). The proposed model incorporates three key
factors which cause the channel spatial non-stationarity: 1) link-wise
path-loss; 2) shadowing effect; 3) line-of-sight (LoS)/non-LoS state. With
appropriate parameter configurations, the proposed model can be used to
generate computer-simulated channel data that matches the published measurement
data from practical ELAA-MIMO channels. Given such appealing results, the
proposed fading channel model is employed to study the cumulative distribution
function (CDF) of ELAA-MIMO channel capacity. For all of our studied scenarios,
it is unveiled that the ELAA-MIMO channel capacity obeys the skew-normal
distribution. Moreover, the channel capacity is also found close to the
Gaussian or Weibull distribution, depending on users' geo-location and
distribution. More specifically, for single-user equivalent scenarios or
multiuser scenarios with short user-to-ELAA distances (e.g., 1 m), the channel
capacity is close to the Gaussian distribution; and for others, it is close to
the Weibull distribution. Finally, the proposed channel model is also employed
to study the impact of channel spatial non-stationarity on linear MIMO
receivers through computer simulations. The proposed fading channel model is
available at https://github.com/ELAA-MIMO/non-stationary-fading-channel-model.