Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: First results from three years of GNSS Interference Monitoring from Low
  Earth Orbit   Observation of terrestrial GNSS interference (jamming and spoofing) from
low-earth orbit (LEO) is a uniquely effective technique for characterizing the
scope, strength, and structure of interference and for estimating transmitter
locations. Such details are useful for situational awareness, interference
deterrence, and for developing interference-hardened GNSS receivers. This paper
presents the results of a three-year study of global interference, with
emphasis on a particularly powerful interference source active in Syria since
2017. It then explores the implications of such interference for GNSS receiver
operation and design.

35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
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The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
4
The categories of this paper are: cond-mat
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The categories of this paper are: dg-ga
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The categories of this paper are: plasm-ph
16
The categories of this paper are: stat
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
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The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
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The categories of this paper are: solv-int
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The categories of this paper are: econ
28
The categories of this paper are: alg-geom
34
The categories of this paper are: chem-ph