Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Noncoherent Multiantenna Receivers for Cognitive Backscatter System with
  Multiple RF Sources
28
The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
0
The categories of this paper are: hep-ph
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
17
The categories of this paper are: q-fin
24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
34
The categories of this paper are: chem-ph
4
The categories of this paper are: cond-mat
1
The categories of this paper are: cs
2
The categories of this paper are: math
8
The categories of this paper are: hep-ex