TransCore MPRX, System Manual

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MPRX
TransCore Proprietary 2–7
• Other MPRXs and antennas in the area
• Reflection, refraction, and diffraction of RF signals
• Existing signal interference at the site
The MPRX Read Zone
The MPRX must be able to read the tag data properly within a specified area, called the
read zone, without reading other nearby tags or interfering with other MPRXs at the site.
The following are some of the factors that affect the size and shape of the read zone:
• Mounting method used for the antenna
• Mounting location of the antenna
• Height from the ground and mounting angle of the antenna
• RF output attenuation
• Range discrimination setting
• 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.
For instructions on setting the read zone, refer to
“Fine-Tuning and Verifying the Read
Zone” on page 8–17
Other MPRXs and Antennas in the Area — AAR-Formatted Tag
Operation
For AAR-formatted (continuous wave) tag operation, sites with more than one MPRX in
proximity should be configured with a frequency separation of at least 2 MHz from adjacent
readers. If more than one MPRX is in a multiple track application, the frequencies should
be staggered. MPRX antennas can face each other across a rail track as long as they are
multiplexed and controlled by the same MPRX. For installations where multiple antennas
are controlled by a host processor with multiple MPRXs, or where multiple MPRXs are
used in close proximity, ensure that there is adequate frequency separation between the
antennas. Contact TransCore Technical Support with any questions.
Table 2 – 1 shows
examples of staggered reader frequencies in a site with up to seven readers.