68P80801E30-A 5/1/2002
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Gen 3 Site Controller System Manual
Chapter 3 Pre-Installation
Antenna Installation
Antenna Installation
The site controller requires antennas for the
Global Positioning System
(GPS)
receivers.
Antenna Surge Arrestors
All antenna feed lines should terminate with a suitable surge arrestor within
12” inside of the entry window. Each arrestor must connect to the master
ground bar located below the entry plate. It is recommended that the
arrestors be mounted to a mounting bracket to simplify grounding and cable
installation.
GPS Antenna Planning
The site controller obtains precise timing information from the GPS. This
system permits all sites in the area to synchronize to a common timing
reference. The EBTS cannot operate properly without tracking satellites.
The site planner must evaluate the proposed site antenna locations prior to
the installation of the system.
GPS Antenna Evaluation
The GPS receiver, mounted within the controller, must locate and track at
least four satellites during initial power-up. The four satellites are used to
establish a three dimensional fix (latitude, longitude, and altitude) for the
site. This process takes approximately 13 to 25 minutes to complete.
Once the position of the site has been established, the corresponding data is
stored in memory and normal operation resumes.
GPS Tracking Criteria
To allow a system to successfully initialize, a minimum of four satellites
must be tracked.
Once a system is operating and the Base Radios have been keyed, at least
one satellite must be tracked to maintain site synchronization. However, to
maintain maximum reliability, three satellites should be tracked at all times.
Note that the system is capable of maintaining site synchronization for short
periods during the loss of satellite tracking.
The system must be capable of the following: