IFM Electronic ANT805, Руководство по эксплуатации

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RFID UHF antennas
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Figure: ANT815 / ANT820 / ANT920 mid-range antenna
3.3 Wide-range antennas
For the conventional far-field applications with reading ranges up to 10 m ifm
offers the ANT830 / ANT930 wide-range antennas that are distinguished by a full
width at half maximum of 70°� The circular polarisation usually required for UHF
applications was significantly improved as compared to the antennas available on
the market� The new versions typically attain an axial ratio of 1 dB that is used as
reference for circular polarisation� The value common on the market, if specified at
all, is approx� 3 dB�
The improved circularity leads
to a considerably reduced
dependence of the read
results on the tag's position or
alignment� Great importance
was also placed on the front-
to-back ratio of the antennas
to reduce the influence of
the close environment on
the antenna properties� All
antennas have an extremely
high protection rating which
guarantees their use in any
industrial environment�
Figure: ANT830 / ANT930 wide-range antenna