Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: End-to-end Throughput Maximization for Underlay Multi-hop Cognitive
  Radio Networks with RF Energy Harvesting   This paper studies a green paradigm for the underlay coexistence of primary
users (PUs) and secondary users (SUs) in energy harvesting cognitive radio
networks (EH-CRNs), wherein battery-free SUs capture both the spectrum and the
energy of PUs to enhance spectrum efficiency and green energy utilization. To
lower the transmit powers of SUs, we employ multi-hop transmission with time
division multiple access, by which SUs first harvest energy from the RF signals
of PUs and then transmit data in the allocated time concurrently with PUs, all
in the licensed spectrum. In this way, the available transmit energy of each SU
mainly depends on the harvested energy before the turn to transmit, namely
energy causality. Meanwhile, the transmit powers of SUs must be strictly
controlled to protect PUs from harmful interference. Thus, subject to the
energy causality constraint and the interference power constraint, we study the
end-to-end throughput maximization problem for optimal time and power
allocation. To solve this nonconvex problem, we first equivalently transform it
into a convex optimization problem and then propose the joint optimal time and
power allocation (JOTPA) algorithm that iteratively solves a series of
feasibility problems until convergence. Extensive simulations evaluate the
performance of EH-CRNs with JOTPA in three typical deployment scenarios and
validate the superiority of JOTPA by making comparisons with two other resource
allocation algorithms.

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The categories of this paper are: physics
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The categories of this paper are: plasm-ph
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The categories of this paper are: nucl-ex
34
The categories of this paper are: chem-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: solv-int
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The categories of this paper are: bayes-an
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The categories of this paper are: adap-org
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The categories of this paper are: chao-dyn
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The categories of this paper are: nlin
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The categories of this paper are: acc-phys
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The categories of this paper are: econ
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The categories of this paper are: hep-ex
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The categories of this paper are: funct-an
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The categories of this paper are: cond-mat
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The categories of this paper are: mtrl-th