  The next generation of cellular networks (5G) will exploit the mmWave
spectrum to increase the available capacity. Communication at such high
frequencies, however, suffers from high path loss and blockage, therefore
directional transmissions using antenna arrays and dense deployments are
needed. Thus, when evaluating the performance of mmWave mobile networks, it is
necessary to accurately model the complex channel, the directionality of the
transmission, but also the interplay that these elements can have with the
whole protocol stack, both in the radio access and in the higher layers. In
this paper, we improve the channel model abstraction of the mmWave module for
ns-3, by introducing the support of a more realistic antenna array model,
compliant with 3GPP NR requirements, and of multiple antenna arrays at the base
stations and mobile handsets. We then study the end-to-end performance of a
mmWave cellular network by varying the channel and antenna array
configurations, and show that increasing the number of antenna arrays and,
consequently, the number of sectors is beneficial for both throughput and
latency.
