Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: UAV-Enabled Radio Access Network: Multi-Mode Communication and
  Trajectory Design   In this paper, we consider an unmanned aerial vehicle (UAV)-enabled radio
access network (RAN) with the UAV acting as an aerial platform to communicate
with a set of ground users (GUs) in a variety of modes of practical interest,
including data collection in the uplink, data transmission in the downlink, and
data relaying between GUs involving both the uplink and downlink. Under this
general framework, two UAV operation scenarios are considered: periodic
operation, where the UAV serves the GUs in a periodic manner by following a
certain trajectory repeatedly, and one-time operation where the UAV serves the
GUs with one single fly and then leaves for another mission. In each scenario,
we aim to minimize the UAV periodic flight duration or mission completion time,
while satisfying the target rate requirement of each GU via a joint UAV
trajectory and communication resource allocation design approach. Iterative
algorithms are proposed to find efficient locally optimal solutions by
utilizing successive convex optimization and block coordinate descent
techniques. Moreover, as the quality of the solutions obtained by the proposed
algorithms critically depends on the initial UAV trajectory adopted, we propose
new methods to design the initial trajectories for both operation scenarios by
leveraging the existing results for solving the classic Traveling Salesman
Problem (TSP) and Pickup-and-Delivery Problem (PDP). Numerical results show
that the proposed trajectory initialization designs lead to significant
performance gains compared to the benchmark initialization based on circular
trajectory.

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The categories of this paper are: astro-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
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The categories of this paper are: stat
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The categories of this paper are: hep-ex
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The categories of this paper are: mtrl-th
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The categories of this paper are: bayes-an
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The categories of this paper are: alg-geom
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The categories of this paper are: q-alg
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The categories of this paper are: comp-gas
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The categories of this paper are: math-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: q-fin
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The categories of this paper are: nlin