Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Channel Rank Improvement in Urban Drone Corridors Using Passive
  Intelligent Reflectors   Multiple-input multiple-output (MIMO) techniques can help in scaling the
achievable air-to-ground (A2G) channel capacity while communicating with
drones. However, spatial multiplexing with drones suffers from rank deficient
channels due to the unobstructed line-of-sight (LoS), especially in
millimeter-wave (mmWave) frequencies that use narrow beams. One possible
solution is utilizing low-cost and low-complexity metamaterial-based
intelligent reflecting surfaces (IRS) to enrich the multipath environment,
taking into account that the drones are restricted to fly only within
well-defined drone corridors. A hurdle with this solution is placing the IRSs
optimally. In this study, we propose an approach for IRS placement with a goal
to improve the spatial multiplexing gains, and hence to maximize the average
channel capacity in a predefined drone corridor. Our results at 6 GHz, 28 GHz
and 60 GHz show that the proposed approach increases the average rates for all
frequency bands for a given drone corridor, when compared with the environment
where there are no IRSs present, and IRS-aided channels perform close to each
other at sub-6 and mmWave bands.

37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
28
The categories of this paper are: alg-geom
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
16
The categories of this paper are: stat
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
26
The categories of this paper are: bayes-an