Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Joint Optimization for RIS-Assisted Wireless Communications: From
  Physics and Electromagnetic Perspectives   Reconfigurable intelligent surfaces (RISs) are envisioned to be a disruptive
wireless communication technique that is capable of reconfiguring the wireless
propagation environment. In this paper, we study a far-field RIS-assisted
multiple-input single-output (MISO) communication system operating in free
space. To maximize the received power of the receiver from the physics and
electromagnetic nature point of view, an optimization, including beamforming of
the transmitter, phase shifts of the RIS, orientation and position of the RIS
is formulated and solved. After exploiting the property of line-of-sight (LoS),
we derive closed-form solutions of beamforming and phase shifts. For the
non-trivial RIS position optimization problem in arbitrary three-dimensional
space, a dimensional-reducing theory is proved. The simulation results show
that the proposed closed-form beamforming and phase shifts are near-optimal
solutions. Besides, the RIS significantly enhances the performance of the
communication system when it is deployed at the optimal position.

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The categories of this paper are: atom-ph
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The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
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The categories of this paper are: alg-geom
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The categories of this paper are: funct-an