Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Potential Key Technologies for 6G Mobile Communications   The standard development of 5G wireless communication culminated between 2017
and 2019, followed by the worldwide deployment of 5G networks, which is
expected to result in very high data rate for enhanced mobile broadband,
support ultra-reliable and low-latency services and accommodate massive number
of connections. Research attention is shifting to future generation of wireless
communications, for instance, beyond 5G or 6G. Unlike previous papers, which
discussed the use cases, deployment scenarios, or new network architectures of
6G in depth, this paper focuses on a few potential technologies for 6G wireless
communications, all of which represent certain fundamental breakthrough at the
physical layer-technical hardcore of any new generation of wireless
communications. Some of them, such as holographic radio, terahertz
communication, large intelligent surface, and orbital angular momentum, are of
revolutionary nature and many related studies are still at their scientific
exploration stage. Several technical areas, such as advanced channel coding and
modulation, visible light communication, and advanced duplex, while having been
studied, may find more opportunities in 6G.

24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
11
The categories of this paper are: hep-lat
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph