  This paper demonstrates the advantages of aperiodic arrays in multi-user
multiple-input multiple-output systems for future mobile communication
applications. We propose a novel aperiodic array synthesis method which account
for the statistics of the propagation channel and the adaptive beamforming
algorithm. Clear performance gains in line-of-sight dominated propagation
environments are achieved in terms of the signal-to-interference-plus-noise
ratio, the sum rate capacity, as well as the spread of the amplifier output
power as compared to their regular counterparts. We also show that the
performance is not sacrificed in rich scattering environments. Hence, aperiodic
array layouts can provide performance gains in millimeter-wave applications
with a dominating line-of-sight component.
