Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Wide-scanning Circularly Polarized Reflector-based Modulated Metasurface
  Antenna Enabled by a Broadband Polarizer   A circularly polarized leaky-wave antenna capable of frequency scanning is
proposed in this paper. The main objective is to achieve high gain and
polarization purity without the need for a complex feed network. The antenna
consists of two independent modules: (1) Anisotropic modulated metasurface
antenna (MoMetA) for generating vertically polarized radiation with an
operational scanning range of 19 to 47 degrees in elevation; (2) Wide-band
polarization converter with high angular stability and capable of converting
vertically linear polarization into circular polarization (CP). Aperture field
estimation (AFE) method is used to design the antenna with high accuracy in
predicting far-field pattern without the need for full-wave simulations. The
gain of antenna in the bandwidth of 16 to 21 GHz is obtained better than 18
dBi. Simulation results show that the axial ratio in the maximum gain direction
is lower than 3 dB all over its operational frequency bandwidth, demonstrating
the proper operation of polarizer. In order to verify the simulation results,
one prototype of the antenna is fabricated and its radiation patterns are
measured in an anechoic chamber

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The categories of this paper are: mtrl-th
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The categories of this paper are: ao-sci
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The categories of this paper are: adap-org
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The categories of this paper are: hep-ex
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The categories of this paper are: q-alg
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The categories of this paper are: dg-ga
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The categories of this paper are: acc-phys
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The categories of this paper are: chao-dyn
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The categories of this paper are: nlin
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The categories of this paper are: math-ph
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The categories of this paper are: q-fin
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The categories of this paper are: bayes-an
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The categories of this paper are: comp-gas
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The categories of this paper are: funct-an
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The categories of this paper are: math
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The categories of this paper are: q-bio