Title: Performance Impact of Base Station Antenna Heights in Dense Cellular Networks,
Abstract: In this paper, we present a new and significant theoretical discovery. If the
absolute height difference between base station (BS) antenna and user equipment
(UE) antenna is larger than zero, then the network performance in terms of both
the coverage probability and the area spectral efficiency (ASE) will
continuously decrease toward zero as the BS density increases for ultra-dense
(UD) small cell networks (SCNs). Such findings are completely different from
the conclusions in existing works, both quantitatively and qualitatively. In
particular, this performance behavior has a tremendous impact on the deployment
of UD SCNs in the 5th-generation (5G) era. Network operators may invest large
amounts of money in deploying more network infrastructure to only obtain an
even less network capacity. Our study results reveal that one way to address
this issue is to lower the SCN BS antenna height to the UE antenna height.
However, this requires a revolutionized approach of BS architecture and
deployment, which is explored in this paper too.