Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Near-field Wireless Power Transfer for 6G Internet-of-Everything Mobile
  Networks: Opportunities and Challenges   Radiating wireless power transfer (WPT) brings forth the possibility to
cost-efficiently charge wireless devices without requiring a wiring
infrastructure. As such, it is expected to play a key role in the deployment of
limited-battery communicating devices, as part of the 6G enabled
Internet-of-Everything (IoE) vision. To date, radiating WPT technologies are
mainly studied and designed assuming that the devices are located in the
far-field region of the power radiating antenna, resulting in a relatively low
energy transfer efficiency. However, with the transition of 6G systems to
mmWave frequencies combined with the usage of large-scale antennas, future WPT
devices are likely to operate in the radiating near-field (Fresnel) region. In
this article, we provide an overview of the opportunities and challenges which
arise from radiating near-field WPT. In particular, we discuss about the
possibility to realize beam focusing in near-field radiating conditions, and
highlight its possible implications for WPT in future {IoE} networks. Besides,
we overview some of the design challenges and research directions which arise
from this emerging paradigm, including its simultaneous operation with wireless
communications, radiating waveform considerations, hardware aspects, and
operation with typical antenna architectures.

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The categories of this paper are: math
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The categories of this paper are: alg-geom
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The categories of this paper are: gr-qc
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The categories of this paper are: funct-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: supr-con
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The categories of this paper are: nucl-th
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-th
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: q-bio
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The categories of this paper are: q-alg
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The categories of this paper are: mtrl-th
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The categories of this paper are: astro-ph
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The categories of this paper are: econ