User's Manual

6-74 Configuring, Installing, and Using Carrier Infrastructure
• The base station contains an antenna connector with a 1/4 wave lightning protector. You
do not need to place an external lightning protector in the coaxial cable.
Connecting the antenna to the base station
To attach the antenna to the base station:
1 Mount the antenna according to the manufacturer’s instructions.
2 Connect one end of a short coaxial jumper to the antenna. Connect the other jumper end
to the main coaxial cable.
3 On the base station’s antenna connector, connect one end of a short coaxial jumper.
Connect the other jumper end to the main coaxial cable coming from the antenna.
4 Make sure the coaxial line is properly grounded.
5 Properly seal the co-axial connections with weatherproof components, tape and wrap.
Connecting the GPS equipment to a base station
The GPS equipment provides a time synchronization signal to the base station. This signal is
needed to ascertain the proper timing for time division duplexing (TDD).
The equipment is a smart antenna in a sealed, shielded, self-contained unit that houses a GPS
receiver, GPS antenna, and interface circuitry.
When powered, the GPS provides accurate time, with a time pulse of one pulse per second,
synchronized to Universal Time, Coordinated (UTC) within 150 nanoseconds.
For information about which GPS kit to use when installing and connecting the GPS, refer to
Table 6.4 and Table 6.5.
GPS equipment mounting tips
You must use the NextNet Wireless supplied GPS system to supply a time synchronization
signal to the base stations in a cell. You cannot use a GPS from another manufacturer.
The GPS does not ship with mounting accessories. You can obtain these accessories from
many suppliers around the world, especially distributors of marine products.
Follow these tips when mounting the GPS:
• Mount the GPS unit on a threaded pipe or pole.
• The GPS mounting socket accepts a 1.0000 x 14 straight thread. It is recommended that
the pole/pipe you use be 1.000 inch.
• Secure the pipe or pole to the building or other support structure.
• Ensure at least half of the sky is clearly visible to the unit.
• Expose the unit to the southern portion of the sky. In the northern hemisphere, GPS
satellites move generally from the southwest to the northeast.
• Mount the GPS away from potential interference sources.
Connecting the GPS unit to the base station
One GPS unit can support numerous base stations in the same cell.