User Manual

Architecture
Nortel Networks Confidential
3–2
PE/DCL/DD/0063
411–9001–063
Standard 12.07/EN September 2000
GSM/BSS V12
Subsystem
Contents*
Base Common Function (BCF)
Cabinet or Unit **
• Control and Switching Module (CSWM)
• Data Signalling Concentration board (DSC)
• PCM Interface board (PCMI)
• Synchronization board (SYNC)
• Alarm Collecting board (ALCO)
• Gateway (GTW)
Compact BCF (CBCF) Module ** • Compact PCM Interface board (CPCMI)
• Compact Main Common Function board
(CMCF)
• Remote Control Alarm (RECAL) board
• BCF Interconnection board (BCFICO)
• CBCF Back Panel (CBP)
TRX • Driver and Receiver unit (DRX or e–DRX)
• Power Amplifier (PA)
Coupling system • RF Combiner Module(s) of the following
types:
– Duplexer (D)
– Hybrid Two–way (H2D)
– Hybrid Four–way (H4D)
– Tx Filter(s) (TxF)
– eight–way cavity combiner (CC8)
• Rx Splitter(s)
• LNA Splitter
* The number of boards or modules are not indicated and depend on the
configuration of a site.
** The BTS contains a BCF or a CBCF.
Table 3–1 BTS subsystems
3.1.3.1 FH bus
The FH bus links together all logical DRXs (or e–DRXs)
The FH bus and the transmitters connected to it ensure the function of frequency
hopping and the filling of the BCCH frequency.
The FH bus is a V11 (series) bus. It is one-way and carries the signals according to
the RS485 standard.