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Very small dimensions for HF (1.5 to 3m rectangle or
diameter)
Can be radomed
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Difficult installations (on roof, small areas, ship,...)
Half-loop capability
to communicate from a moving vehicle.
Discrete stations
(fixed and mobile)
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Low take-off angle propagation andGround wave radiation
(8-shaped pattern)+Near Vertical Incidence Skywave (NVIS)
Directivity: + 2dB
in free space and +5dB or +6 dB on a conductive ground
Gain: - 12/-15 dBi at lowest frequencies to+ 2/+ 5 dBi
at highest frequencies.
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Communications up to 1000km with 125W, without silent
zone in azimuth nor petal nulls
in elevation.
Communications of
the ships along the coasts and over mountains.
One antenna only gives
the equivalent services of a NVIS antenna (like horizontal
dipole) and a vertical whip (at longer ranges).
Achievement of an ALE fully automated mobile station: no more need to change
antennas at halt alongside the classic silent zone of
whips.
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High selectivity in the lowest range.
High reduction of
outband transmissions.
High reduction of
received noise and improvement of the Signal/Noise ratio(typically
6 to 10dB in reception compared to the wider band antennas
like tuned whips or dipoles)
High rejection of
the strong wideband signals like high voltage lines spurious,
indirect effects of lightening, etc...
2 tuned loops are
highly isolated (particularly when they are perpendicular
with one frame in the central axis of the other one).
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Compared to the whip antennas: Better listening comfort,
reduced Bit Error Rate (BER) of data transmissions or
FH synchronisation signals. Extra filters can be avoided
in many applications.
Operational in industrial
zones and areas of frequent lightning.
Simultaneous transmission
and reception on the same narrow site (head of a star
chained network, duplex station, HF-HF relay,...)
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