Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An Overview of Low latency for Wireless Communications: an Evolutionary
  Perspective   Ultra-low latency supported by the fifth generation (5G) give impetus to the
prosperity of many wireless network applications, such as autonomous driving,
robotics, telepresence, virtual reality and so on. Ultra-low latency is not
achieved in a moment, but requires long-term evolution of network structure and
key enabling communication technologies. In this paper, we provide an
evolutionary overview of low latency in mobile communication systems, including
two different evolutionary perspectives: 1) network architecture; 2) physical
layer air interface technologies. We firstly describe in detail the evolution
of communication network architecture from the second generation (2G) to 5G,
highlighting the key points reducing latency. Moreover, we review the evolution
of key enabling technologies in the physical layer from 2G to 5G, which is also
aimed at reducing latency. We also discussed the challenges and future research
directions for low latency in network architecture and physical layer.

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The categories of this paper are: eess
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
11
The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio
6
The categories of this paper are: astro-ph
3
The categories of this paper are: physics
9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
14
The categories of this paper are: math-ph
18
The categories of this paper are: econ
24
The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th