Fractional Atm Networking; Cascading With Odu3601Cs - Huawei Airbridge BTS3612A-1900 Technical Manual

Technical Manual
Airbridge BTS3612A CDMA Base Station
be allocated to each of the lower-level BTSs. (Note that these BTSs do not share the
same trunk lines.) The lower-level BTS can in turn allocate the trunk links to its own
lower-level BTSs. In this way, a tree network comes into being.

8.5.4 Fractional ATM Networking

I. Application scope
When the transmission resource is rather limited and the BTS capacity is not large,
BTS3612A supports the fractional ATM networking. That is, BTS only uses specific
timeslots in one or more E1/T1 links.
Fractional ATM networking is similar with the tree networking, except that in the
fractional ATM networking mode, only part of the timeslots of E1/T1 links are used.
II. Advantage
In this mode, transmission resource can be fully and flexibly utilized and thus related
cost can be reduced.
III. Disavantage
The capacity of BTS cannot be too large due to the restriction of transmission
resource. If the actual BTS capacity is more than what the transmission resource can
support, the call connected ratio will be affected.
The failure of upper-level BTS may affect the normal operation of lower-level BTS.
Expansion is not easy and may cause substantial network reconstruction.
IV. Implementation
BTS3612A can use the timeslot cross-connection function of QC52BCIM board to
implement the fractional ATM networking without the support of external equipment.
In practice, the timeslot cross-connection should be added to the upper-level BTS,
while the E1/T1 timeslots should be specified for the lower-level BTS by adding the
E1/T1 fractional ATM transmission link to this BTS.

8.5.5 Cascading with ODU3601Cs

I. Application scope
The ODU3601C is an outdoor soft BTS. By connecting ODU3601 to a master
BTS3612A in cascading mode, flexible coverage can be realized, including the indoor
coverage, underground coverage, and coverage of highways and railways.
8-11
System Principle
Chapter 8 BTS Configuration