  Provisioning of high throughput millimetre-wave signal to indoor areas that
potentially serve a large number of users, such as transportation hubs or
convention centres, will require dedicated indoor millimetre-wave access point
deployments. In this article, we study dense deployments of millimetre-wave
access points mounted on the ceiling and illuminating selected spots on the
ground with the use of fixed directional antennas. In this setup, the main
factor limiting signal propagation are blockages by human bodies. We evaluate
our system under a number of scenarios that take into account beamwidth of the
main-lobe, access point density, and positioning of the mobile device with
respect to the user's body. We find that both coverage and area spectral
efficiency curves exhibit non-trivial behaviour which can be classified into
four regions related to the selection of access point density, beamwidth, and
height values. Furthermore, we observe a trade-off in beamwidth design, as the
optimal beamwidth maximizes either coverage or area spectral efficiency, but
not both. Finally, when we consider different body shadowing scenarios, our
network design optimizes coverage or area spectral efficiency performance
towards either devices held in hand or worn directly against the body, as each
of the scenarios requires mutually exclusive settings of access point density
and beamwidth.
