Huawei Airbridge BTS3612A-1900 Technical Manual page 54

Technical Manual
Airbridge BTS3612A CDMA Base Station
In consideration of system security and reliability, the BTS receives signals of the GPS
system or of the GLONASS system through a satellite synchronization antenna &
feeder, to implement radio synchronization. In this way, the whole network can still
operate normally without any adverse effect when the GPS or GLONASS system is not
available.
A satellite synchronization antenna & feeder system is composed of an antenna, the
jumper from antenna to feeder, feeders, a lightning arrester and the jumper from feeder
to cabinet-bottom (the feeders and jumpers can be configured as needed). Figure 4-2
shows the structure.
Antenna
Jumper
Feeder
Jumper
Lightning arrester
Figure 4-2 Structure of satellite synchronization antenna & feeder
Note:
When the length of the feeder is within 100m, use the 1/2" feeder, which can be directly connected to the
antenna and lightning arrester without any jumper.
When the length of the feeder exceeds 100m, use the 7/8" feeder. In this case, a jumper is needed.
Generally, one BTS is configured with one set of satellite synchronization antenna &
feeder. However, if two BCKM boards are configured to further enhance the reliability of
the system, the two BCKMs each should be configured with one set of independent
satellite synchronization antenna & feeder. In Figure 4-2, two satellite synchronization
antenna & feeder interfaces are provided.
The following describes the application of the GPS and the GLONASS in a CDMA BTS.
BTS cabinet
4-5
Chapter 4 Antenna & Feeder Subsystem
System Principle