3,230 research outputs found
Please Lower Small Cell Antenna Heights in 5G
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 capacity performance in
terms of the area spectral efficiency (ASE) will continuously decrease as the
BS density increases for ultra-dense (UD) small cell networks (SCNs). 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 worse
network performance. Our study results reveal that it is a must to lower the
SCN BS antenna height to the UE antenna height to fully achieve the capacity
gains of UD SCNs in 5G. However, this requires a revolutionized approach of BS
architecture and deployment, which is explored in this paper too.Comment: Final version in IEEE: http://ieeexplore.ieee.org/document/7842150/.
arXiv admin note: substantial text overlap with arXiv:1608.0669
Ultra-Dense Networks: Is There a Limit to Spatial Spectrum Reuse?
The aggressive spatial spectrum reuse (SSR) by network densification using
smaller cells has successfully driven the wireless communication industry
onward in the past decades. In our future journey toward ultra-dense networks
(UDNs), a fundamental question needs to be answered. Is there a limit to SSR?
In other words, when we deploy thousands or millions of small cell base
stations (BSs) per square kilometer, is activating all BSs on the same
time/frequency resource the best strategy? In this paper, we present
theoretical analyses to answer such question. In particular, we find that both
the signal and interference powers become bounded in practical UDNs with a
non-zero BS-to-UE antenna height difference and a finite UE density, which
leads to a constant capacity scaling law. As a result, there exists an optimal
SSR density that can maximize the network capacity. Hence, the limit to SSR
should be considered in the operation of future UDNs.Comment: conference submission in Oct. 201
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