Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Next Generation Backscatter Communication: Systems, Techniques and
  Applications   The rapid growth of IoT driven by recent advancements in consumer
electronics, 5G communication technologies, and cloud-computing enabled
big-data analytics, has recently attracted tremendous attention from both the
industry and academia. One of the major open challenges for IoT is the limited
network lifetime due to massive IoT devices being powered by batteries with
finite capacities. The low-power and low-complexity backscatter communications
(BackCom), which simply relies on passive reflection and modulation of an
incident radio-frequency (RF) wave, has emerged to be a promising technology
for tackling this challenge. However, the contemporary BackCom has several
major limitations, such as short transmission range, low data rate, and
uni-directional information transmission. The article aims at introducing the
recent advances in the active area of BackCom. Specifically, we provide a
systematic introduction of the next generation BackCom covering basic
principles, systems, techniques besides IoT applications. Lastly, we describe
the IoT application scenarios with the next generation BackCom.

3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
16
The categories of this paper are: stat
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
34
The categories of this paper are: chem-ph
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The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph