Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Sparse Array of Sub-surface Aided Anti-blockage mmWave Communication
  Systems   Recently, reconfigurable intelligent surfaces (RISs) have drawn intensive
attention to enhance the coverage of millimeter wave (mmWave) communication
systems. However, existing works mainly consider the RIS as a whole uniform
plane, which may be unrealistic to be installed on the facade of buildings when
the RIS is extreme large. To address this problem, in this paper, we propose a
sparse array of sub-surface (SAoS) architecture for RIS, which contains several
rectangle shaped sub-surfaces termed as RIS tiles that can be sparsely
deployed. An approximated ergodic spectral efficiency of the SAoS aided system
is derived and the performance impact of the SAoS design is evaluated. Based on
the approximated ergodic spectral efficiency, we obtain an optimal reflection
coefficient design for each RIS tile. Analytical results show that the received
signal-to-noise ratios can grow quadratically and linearly to the number of RIS
elements under strong and weak LoS scenarios, respectively. Furthermore, we
consider the visible region (VR) phenomenon in the SAoS aided mmWave system and
find that the optimal distance between RIS tiles is supposed to yield a total
SAoS VR nearly covering the whole blind coverage area. The numerical results
verify the tightness of the approximated ergodic spectral efficiency and
demonstrate the great system performance.

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The categories of this paper are: mtrl-th
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The categories of this paper are: math-ph
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The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
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The categories of this paper are: astro-ph
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
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The categories of this paper are: stat
4
The categories of this paper are: cond-mat
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The categories of this paper are: chem-ph
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The categories of this paper are: funct-an
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The categories of this paper are: q-bio
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The categories of this paper are: solv-int
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The categories of this paper are: nucl-ex