Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Learning-Based Downlink Power Allocation in Cell-Free Massive MIMO
  Systems   This paper considers a cell-free massive multiple-input multiple-output
(MIMO) system that consists of a large number of geographically distributed
access points (APs) serving multiple users via coherent joint transmission. The
downlink performance of the system is evaluated, with maximum ratio and
regularized zero-forcing precoding, under two optimization objectives for power
allocation: sum spectral efficiency (SE) maximization and proportional
fairness. We present iterative centralized algorithms for solving these
problems. Aiming at a less computationally complex and also distributed
scalable solution, we train a deep neural network (DNN) to approximate the same
network-wide power allocation. Instead of training our DNN to mimic the actual
optimization procedure, we use a heuristic power allocation, based on
large-scale fading (LSF) parameters, as the pre-processed input to the DNN. We
train the DNN to refine the heuristic scheme, thereby providing higher SE,
using only local information at each AP. Another distributed DNN that exploits
side information assumed to be available at the central processing unit is
designed for improved performance. Further, we develop a clustered DNN model
where the LSF parameters of a small number of APs, forming a cluster within a
relatively large network, are used to jointly approximate the power
coefficients of the cluster.

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The categories of this paper are: cond-mat
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The categories of this paper are: hep-lat
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
30
The categories of this paper are: q-alg
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The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph
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The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: acc-phys
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The categories of this paper are: math-ph
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The categories of this paper are: econ
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-bio