Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Low-Power Wide-Area Networks for Sustainable IoT   Low-power wide-area (LPWA) networks are attracting extensive attention
because of their abilities to offer low-cost and massive connectivity to
Internet of Things (IoT) devices distributed over wide geographical areas. This
article provides a brief overview on the existing LPWA technologies and useful
insights to aid the large-scale deployment of LPWA networks. Particularly, we
first review the currently competing candidates of LPWA networks, such as
narrowband IoT (NB-IoT) and long range (LoRa), in terms of technical
fundamentals and large-scale deployment potential. Then we present two
implementation examples on LPWA networks. By analyzing the field-test results,
we identify several challenges that prevent LPWA technologies moving from the
theory to wide-spread practice.

31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
15
The categories of this paper are: nucl-ex
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
4
The categories of this paper are: cond-mat
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
7
The categories of this paper are: hep-th
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg