User Manual
Airbridge cBTS3612 CDMA Base Station
System Description
4 System Function
4-2
Chain networking is a perfect solution to certain requirements and can save the
transmission resources.
The disadvantage of this mode is that signals should pass quite a few network
sections, making the line less reliable. The nodes cascaded should not be more
than 3.
B S C
B T S
B T S
B T S
E 1
E 1
E 1
Figure 4-2
BTS chain networking
III. Tree networking
Tree networking mode applies to the area where network structure, site and
subscriber distribution are complicated, such as the area where users are not evenly
distributed. Tree networking is as shown in Figure 4-3.
In this mode, signals go through many links, so the line reliability is low, and
implementation and maintenance are difficult. In addition, the fault in the upper-level
BTS may affect the normal operation of the lower-level BTSs. Expansion is not easy
and may cause substantial network reconstruction. However, tree networking
requires much less transmission lines than star networking. The cascaded BTSs
should not be more than 3 levels, i.e. the depth of the tree should not exceed 3
layers.
BSC
BTS
BTS
BTS
E1
E1
E1
BTS
BTS
E1
E1
Figure 4-3
BTS tree networking
It is common practice that the above three modes be used together. Proper
application of different modes inproves service quality and saves investment on the
transmission equipment.