Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Impact of Antenna Height Difference on the Performance of Downlink
  Cellular Networks   Capable of significantly reducing cell size and enhancing spatial reuse,
network densification is shown to be one of the most dominant approaches to
expand network capacity. Due to the scarcity of available spectrum resources,
nevertheless, the over-deployment of network infrastructures, e.g., cellular
base stations (BSs), would strengthen the inter-cell interference as well, thus
in turn deteriorating the system performance. On this account, we investigate
the performance of downlink cellular networks in terms of user coverage
probability (CP) and network spatial throughput (ST), aiming to shed light on
the limitation of network densification. Notably, it is shown that both CP and
ST would be degraded and even diminish to be zero when BS density is
sufficiently large, provided that practical antenna height difference (AHD)
between BSs and users is involved to characterize pathloss. Moreover, the
results also reveal that the increase of network ST is at the expense of the
degradation of CP. Therefore, to balance the tradeoff between user and network
performance, we further study the critical density, under which ST could be
maximized under the CP constraint. Through a special case study, it follows
that the critical density is inversely proportional to the square of AHD. The
results in this work could provide helpful guideline towards the application of
network densification in the next-generation wireless networks.

23
The categories of this paper are: solv-int
15
The categories of this paper are: nucl-ex
11
The categories of this paper are: hep-lat
32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
6
The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci
16
The categories of this paper are: stat
24
The categories of this paper are: dg-ga