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7.3 Selecting an Antenna Installation Location
CAUTION
If antenna is not located in the method described below, it may not be possible to receive the
GPS signal correctly.
A
ntenna
Support pole
(
fix to fence etc.
)
Neighbouring
building
Roof of building
15
°
(maximum)
Obstructing object is not
allowed in this area.
The antenna is installed outdoors to receive satellite transmissions. It should be installed in a
location that offers an unobstructed view of the sky with an elevation angle of 15 degrees to
horizontal. This is imperative for operation in high-reliability mode with operation of the
TRAIM function, since it is necessary to received signals from satellites which are widely
spaced. These restrictions can be relaxed for normal mode operation.
Since the alignment of satellites varies during the course of a day, it is necessary to test that the
installation is adequate to allow immediate location estimation and continuous 1PPS output for
an entire one day period.
On sites where installation conditions are not ideal then it may be necessary to conduct a survey
to establish whether reception quality is adequate. This may include situations where the antenna
must be mounted on a wall, or if the visual field is narrow or if the site is close to structures which
reflect electromagnetic waves.