Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Optimizing Multi-Cell Massive MIMO for Spectral Efficiency: How Many
  Users Should Be Scheduled?   Massive MIMO is a promising technique to increase the spectral efficiency of
cellular networks, by deploying antenna arrays with hundreds or thousands of
active elements at the base stations and performing coherent beamforming. A
common rule-of-thumb is that these systems should have an order of magnitude
more antennas, $N$, than scheduled users, $K$, because the users' channels are
then likely to be quasi-orthogonal. However, it has not been proved that this
rule-of-thumb actually maximizes the spectral efficiency. In this paper, we
analyze how the optimal number of scheduled users, $K^\star$, depends on $N$
and other system parameters. The value of $K^\star$ in the large-$N$ regime is
derived in closed form, while simulations are used to show what happens at
finite $N$, in different interference scenarios, and for different beamforming.

17
The categories of this paper are: q-fin
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess
29
The categories of this paper are: funct-an
4
The categories of this paper are: cond-mat
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
33
The categories of this paper are: plasm-ph
12
The categories of this paper are: nucl-th
18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph