Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Relay Selection for Cooperative NOMA   This letter studies the impact of relay selection (RS) on the performance of
cooperative non-orthogonal multiple access (NOMA). In particular, a two-stage
RS strategy is proposed, and analytical results are developed to demonstrate
that this two-stage strategy can achieve the minimal outage probability among
all possible RS schemes, and realize the maximal diversity gain. The provided
simulation results show that cooperative NOMA with this two-stage RS scheme
outperforms that with the conventional max-min approach, and can also yield a
significant performance gain over orthogonal multiple access.

20
The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
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The categories of this paper are: hep-lat
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The categories of this paper are: eess
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The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg