Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Performance Analysis of Massive MIMO for Cell-Boundary Users   In this paper, we consider massive multiple-input multiple-output (MIMO)
systems for both downlink and uplink scenarios, where three radio units (RUs)
connected via one digital unit (DU) support multiple user equipments (UEs) at
the cell-boundary through the same radio resource, i.e., the same
time-frequency slot. For downlink transmitter options, the study considers
zero-forcing (ZF) and maximum ratio transmission (MRT), while for uplink
receiver options it considers ZF and maximum ratio combining (MRC). For the sum
rate of each of these, we derive simple closed-form formulas. In the simple but
practically relevant case where uniform power is allocated to all downlink data
streams, we observe that, for the downlink, vector normalization is better for
ZF while matrix normalization is better for MRT. For a given antenna and user
configuration, we also derive analytically the signal-to-noise-ratio (SNR)
level below which MRC should be used instead of ZF. Numerical simulations
confirm our analytical results.

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The categories of this paper are: acc-phys
13
The categories of this paper are: quant-ph
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
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The categories of this paper are: stat
7
The categories of this paper are: hep-th
23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
10
The categories of this paper are: q-bio
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The categories of this paper are: eess
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The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
5
The categories of this paper are: gr-qc