Ross SRG-4400, User Manual

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SRG-4400 User Manual (Iss. 06) GPS Option • 14–3
System Requirements
The SRG-4400 requires an Option Key to enable the GPS sub-system. Additional optional GPS
components are available when the GPS Option is ordered as part of your system.
The system works best with a GPS signal level between -125dBm and -117dBm at the SMB plug
at the rear of the unit. It can achieve cold start with a -147dBm signal.
Recommended Cables
Table 14.1 summarizes the cable types if you do not purchase one of our GPS options that
include the necessary cables.
Cable, Antenna, and Amplifier Combinations
Table 14.2 summarizes the recommended cabling specifications. Refer also to Figure 14.5 and
Figure 14.7 .
Table 14.1 Recommended Cables
Cable
Signal
Attenuation
Outer
Diameter
DC
Resistance
Bending
Radius
Operating
Temperature
RG58 Black PVC
or LBC/LMR195
0.66dB/m @ 1.6GHz 5mm 0.05ohms/m 25mm -40 to +80°C
LBC/LMR400
Black polyethylene
0.18dB/m @ 1.6GHz 10.25mm 0.01ohms/m 50mm -40 to +80°C
Warning
— The cable supplied with the GPS-4400-8M and GPS-4400-35M is type
LMR195FR or equivalent. In the GPS-4400-100M and GPS-4400-200M include the
same cable as found in the GPS-4400-8M plus 100M (or 200M) of LMR400FR. These
cables are not a plenum rated. Before installation, verify that the supplied cable(s)
meet the local regulatory requirements for your facility.
Table 14.2 Possible Combinations
Antenna Cable Amplifier
Extension
Cable
Overall
Gain at RF
Input
Expected
DC Volts at
Antenna
GPS-4400-8M +28dB 8m of RG58 none none +22.72dB 4.99
GPS-4400-35M +28dB 35m of RG58 none none +4.9dB 4.97
GPS-4400-100M +28dB 8m of RG58 none 100m of 4.72dB 4.97
GPS-4400-200M +28dB 8m of RG58 +28dB 200m of 14.72dB 4.93