TransCore SmartPass AI1611, Системное руководство

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Chapter 2
Preparing the Site
Before installing SmartPass, you need to develop a site plan. Several
factors to consider when developing this site plan include the
following:
•
SmartPass mounting locations
•
Junction box requirements
•
Electrical power requirements
•
Communications requirements
•
Input/output circuit requirements for outside equipment
Warning
All construction work required for installing SmartPass must be completed before
installing SmartPass. Additionally, communications and power cables must be
installed through outdoor-grade, flexible steel conduit. Local building code
requirements should be followed.
Determining the Location to Install SmartPass
The location of SmartPass and the location of the tags must be compatible. Each tag
must be in a direct line of sight to the reader.
You should also consider the following factors when determining a SmartPass
installation location:
•
Reflection, refraction, and diffraction of RF energy
•
Existing interference at the site that may need to be shielded or removed, such as
fluorescent lights, neon signs, nearby radio stations, or power lines
•
Site area layout and traffic flow
•
Location and read zone of other SmartPass units in the area
Reflection, Refraction, and Diffraction of RF
Signals
The RF signal can be reflected, refracted, or diffracted by metal objects, walls, and
even wet pavement or ice. When designing your site, you must take into account any
permanent structures that may reflect RF signals, as well as transient factors.
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