Gps signal strength requirements, Making additional connections, Warning – Symmetricom XL-GPS User Manual
Page 25
997-01530-01, Rev. C-25, Jan 2008
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GPS Signal Strength Requirements
Refer to
The required gain at the GPS receiver’s ANTENNA connector is greater than 20 dB
and less than 36 dB. A standard 150 foot length of RG-59 coax cable of has a loss of 16-21 dB, which
meets this requirement. Abide by the minimum input gain requirements if using other cable types.
Additionally, if changing the antenna, abide by the 41 dB gain requirement. Other factors, such as
radiation, coverage, VSWR, and input impedance also affect system performance. Symmetricom
recommends using the standard antenna and cable provided with the GPS receiver.
Figure 2: GPS Signal Strength Requirements
Making Additional Connections
Make the following optional connections:
•
ANTENNA:
GPS receiver antenna connector with GPS antenna cable. See “GPS Receiver” on
page 133 for more information.
Warning:
Use a 12-volt capable GPS antenna.
•
NET:
network port with the Cat-5 network cable (supplied) to an Ethernet network. (Needed to
manage the XL-GPS remotely by network, or optionally to distribute NTP time information)
•
SERIAL I/O:
with RS-232 null modem cable (supplied) to the serial port on a PC.
•
For J1, J2, J3, and any other option cards: See also