TransCore 05716 Manuel D’Utilisation
Multiprotocol Rail Reader System Guide
2-8
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RF output attenuation
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Range discrimination setting
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Other sources of interference and reflection
The railside antenna must be positioned so that the RF signal travels to and return
from the tags within the designated range and must be placed in an area where it is not
likely to be bumped out of alignment. If the antenna becomes misaligned or some
nearby structure is added or removed, system operation can be seriously affected.
from the tags within the designated range and must be placed in an area where it is not
likely to be bumped out of alignment. If the antenna becomes misaligned or some
nearby structure is added or removed, system operation can be seriously affected.
For instructions on setting the read zone, see
Other MPRRs in the Area
Sites with more than one MPRR in proximity should have them configured with a fre-
quency separation of at least 2 MHz from adjacent readers. If more than one MPRR is
in a side-by-side or multiple track application, the frequencies should be staggered.
MPRR antennas can face each other across a rail track as long as they are multiplexed
and controlled by the same MPRR.
quency separation of at least 2 MHz from adjacent readers. If more than one MPRR is
in a side-by-side or multiple track application, the frequencies should be staggered.
MPRR antennas can face each other across a rail track as long as they are multiplexed
and controlled by the same MPRR.
shows examples of staggered reader fre-
quencies in a site with up to 5 readers.
Reflection, Refraction, and Diffraction of RF
Signals
Signals
RF signals can be reflected, refracted, or diffracted by metal objects, walls, and even
wet pavement or ice. Any of these factors can alter or degrade system performance.
When designing your site plan, you must consider permanent structures and transient
factors in the vicinity that may affect RF signals being generated by the MPRR. Per-
manent structures include buildings, chain link fences, guard shacks, and gates. Tran-
sient factors include passing traffic and local weather conditions, such as rain or snow.
Symptoms of reflection, refraction, and diffraction include reading tags that are out of
the desired read zone or tags being read from another track.
wet pavement or ice. Any of these factors can alter or degrade system performance.
When designing your site plan, you must consider permanent structures and transient
factors in the vicinity that may affect RF signals being generated by the MPRR. Per-
manent structures include buildings, chain link fences, guard shacks, and gates. Tran-
sient factors include passing traffic and local weather conditions, such as rain or snow.
Symptoms of reflection, refraction, and diffraction include reading tags that are out of
the desired read zone or tags being read from another track.
The most common RF reflectors are metallic surfaces. RF signals may also be par-
tially reflected by nonconducting materials such as dirt, wood, ice, asphalt, and con-
crete. When nonconducting materials in the system environment become wet, they
increase reflection of RF signals.
tially reflected by nonconducting materials such as dirt, wood, ice, asphalt, and con-
crete. When nonconducting materials in the system environment become wet, they
increase reflection of RF signals.
Table 2-1 Examples of Staggered Reader Frequencies
Rail Number
Reader Frequency
Rail Number
Reader Frequency
1
911.75
2
913.75
3
915.75
4
917.75
5
919.75