Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Elements of Radio Waves   We present a summary of the basic properties of the radio wave generation,
propagation and reception, with a special attention to the gigahertz bandwidth
region which is of interest for wireless sensor networks. We also present some
measurement results which use the so-called RSSI indicator in order to track
how the field strength varies with position and distance of the transceivers.
We hope the paper may be useful to anyone who looks for a quick review of the
fundamentals of electromagnetic theory with application to antennas.

7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
16
The categories of this paper are: stat
22
The categories of this paper are: chao-dyn
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex
0
The categories of this paper are: hep-ph
13
The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
6
The categories of this paper are: astro-ph
29
The categories of this paper are: funct-an