TransCore MPRX, System Manual

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MPRX
TransCore Proprietary 2–9
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 partially
reflected by nonconducting materials such as dirt containing high concentrations of
metallic rail dust, wood, ice, asphalt, and concrete. When nonconducting materials in the
system environment become wet, they increase reflection of RF signals.
The antenna mounting location, aiming, and range control adjustment, and use of presence
detectors can reduce interference from RF reflections. When these actions cannot
adequately control reflections, other techniques such as shielding, absorbing, range
sensitivity adjustment, or barriers can also be used. Refer to
“Chapter 9 Troubleshooting
and Maintenance” for information about troubleshooting and maintenance.
Existing Signal Interference at the Site
Interference from RF and electrical sources can degrade system performance and also
must also be considered in the site design. Fluorescent lights, neon signs, nearby radio
stations, or power lines can interfere with the optimal operation of the system.
Interference may degrade both reader and tag performance. Existing sources of
interference at the site should be shielded, removed, or positioned farther from the
antenna. In some cases, changing the operating frequency of the MPRX may provide a
simple solution. Readers in proximity should have at least a 2 MHz frequency separation.
Refer to
“Other MPRXs and Antennas in the Area — AAR-Formatted Tag Operation” on
page 2–7. Strong RF sources of any frequency, in proximity to the tag, can preclude
the tag receiving the reader interrogation. Refer to “Chapter 4 Installing the MPRX” for
information about troubleshooting and maintenance.
Electrical and Communications Requirements
All construction work at the site must be completed before installing the MPRX. Electrical
and communications cables should be installed according to all applicable local and
federal building code requirements. Specific instructions for positioning and installing the
MPRX are discussed in
“Chapter 4 Installing the MPRX”.
Power and Communications Cables
Cable length for power and communications depends on the physical characteristics of the
MPRX installation site.
Table 2 – 3 l ists accessory kits available for cabling options based
on your site’s requirements.