Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Weighted Sum-Rate Maximization in Multi-Carrier NOMA with Cellular Power
  Constraint   Non-orthogonal multiple access (NOMA) has received significant attention for
future wireless networks. NOMA outperforms orthogonal schemes, such as OFDMA,
in terms of spectral efficiency and massive connectivity. The joint subcarrier
and power allocation problem in NOMA is NP-hard to solve in general, due to
complex impacts of signal superposition on each user's achievable data rates,
as well as combinatorial constraints on the number of multiplexed users per
sub-carrier to mitigate error propagation. In this family of problems, weighted
sum-rate (WSR) is an important objective function as it can achieve different
tradeoffs between sum-rate performance and user fairness. We propose a novel
approach to solve the WSR maximization problem in multi-carrier NOMA with
cellular power constraint. The problem is divided into two polynomial time
solvable sub-problems. First, the multi-carrier power control (given a fixed
subcarrier allocation) is non-convex. By taking advantage of its separability
property, we design an optimal and low complexity algorithm (MCPC) based on
projected gradient descent. Secondly, the single-carrier user selection is a
non-convex mixed-integer problem that we solve using dynamic programming
(SCUS). This work also aims to give an understanding on how each sub-problem's
particular structure can facilitate the algorithm design. In that respect, the
above MCPC and SCUS are basic building blocks that can be applied in a wide
range of resource allocation problems. Furthermore, we propose an efficient
heuristic to solve the general WSR maximization problem by combining MCPC and
SCUS. Numerical results show that it achieves near-optimal sum-rate with user
fairness, as well as significant performance improvement over OMA.

34
The categories of this paper are: chem-ph
23
The categories of this paper are: solv-int
3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
2
The categories of this paper are: math
9
The categories of this paper are: nlin
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The categories of this paper are: eess
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The categories of this paper are: supr-con
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The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
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The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
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The categories of this paper are: plasm-ph
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The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph