Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Simultaneous Information and Power Transfer for Broadband Wireless
  Systems   Far-field microwave power transfer (MPT) will free wireless sensors and other
mobile devices from the constraints imposed by finite battery capacities.
Integrating MPT with wireless communications to support simultaneous
information and power transfer (SIPT) allows the same spectrum to be used for
dual purposes without compromising the quality of service. A novel approach is
presented in this paper for realizing SIPT in a broadband system where
orthogonal frequency division multiplexing and transmit beamforming are
deployed to create a set of parallel sub-channels for SIPT, which simplifies
resource allocation. Supported by a proposed reconfigurable mobile
architecture, different system configurations are considered by combining
single-user/multiuser systems, downlink/uplink information transfer, and
variable/fixed coding rates. Optimizing the power control for these
configurations results in a new class of multiuser power-control problems
featuring circuit-power constraints, specifying that the transferred power must
be sufficiently large to support the operation of the receiver circuitry.
Solving these problems gives a set of power-control algorithms that exploit
channel diversity in frequency for simultaneously enhancing the throughput and
the MPT efficiency. For the system configurations with variable coding rates,
the algorithms are variants of water-filling that account for the circuit-power
constraints. The optimal algorithms for those configurations with fixed coding
rates are shown to sequentially allocate mobiles their required power for
decoding in the ascending order until the entire budgeted power is spent. The
required power for a mobile is derived as simple functions of the minimum
signal-to-noise ratio for correct decoding, the circuit power and sub-channel
gains.

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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-th
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The categories of this paper are: q-bio
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The categories of this paper are: astro-ph
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The categories of this paper are: q-fin
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The categories of this paper are: cond-mat
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The categories of this paper are: stat
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The categories of this paper are: physics
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The categories of this paper are: gr-qc
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The categories of this paper are: nlin
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The categories of this paper are: quant-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: patt-sol
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The categories of this paper are: econ
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The categories of this paper are: funct-an
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The categories of this paper are: nucl-th