Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Online Learning for Position-Aided Millimeter Wave Beam Training   Accurate beam alignment is essential for beam-based millimeter wave
communications. Conventional beam sweeping solutions often have large overhead,
which is unacceptable for mobile applications like vehicle-to-everything.
Learning-based solutions that leverage sensor data like position to identify
good beam directions are one approach to reduce the overhead. Most existing
solutions, though, are supervised-learning where the training data is collected
beforehand. In this paper, we use a multi-armed bandit framework to develop
online learning algorithms for beam pair selection and refinement. The beam
pair selection algorithm learns coarse beam directions in some predefined beam
codebook, e.g., in discrete angles separated by the 3dB beamwidths. The beam
refinement fine-tunes the identified directions to match the peak of the power
angular spectrum at that position. The beam pair selection uses the upper
confidence bound (UCB) with a newly proposed risk-aware feature, while the beam
refinement uses a modified optimistic optimization algorithm. The proposed
algorithms learn to recommend good beam pairs quickly. When using 16x16 arrays
at both the transmitter and receiver, it can achieve on average 1dB gain over
the exhaustive search (over 271x271 beam pairs) on the unrefined codebook
within 100 time-steps with a training budget of only 30 beam pairs.

15
The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
7
The categories of this paper are: hep-th
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
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The categories of this paper are: dg-ga
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The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th