Nortel Networks DCT1900 - Manual (Page 39)

Technical Product Manual - DCT1900
System Description, Radio Exchange Boards
System-DCT1900/R8/mw 4-1
© 2000-2005
C HAPTER 4
Radio Exchange Boards
4.1 General
The RE can contain the following System Board types:
z Central Processing Unit (CPU REX-BRD0004)
(CPU2 REX-BRD9033 and REX-BRD9034)
z Speech Processing Unit (SPU-S REX-BRD0017)
z Cell Link Unit (CLU REX-BRD0014)
(CLU-S REX-BRD0016)
z Speech Link Unit (SLU REX-BRD0015)
z Digital Trunk Unit (DTU E1,CCS REX-BRD0003)
(DTU E1, CAS REX-BRD0002)
(DTU T1, CAS REX-BRD0021)
(DTU T1, CCS REX-BRD0025)
z Line Termination Unit (LTU REX-BRD0007) (Standalone only)
(LTU2 REXBRD0019A)
z Digital Line Unit (DLU REX-BRD0023) (Standalone only)
The RE consists of up to 4 Modular Cabinets. A Modular Cabinet contains, besides the slots for
the System Boards, a MCCB and if required, a SDB.
4.2 Central Processing Unit - CPU1 (REX-BRD0004 or 2/ROFNB 157 19/2),
CPU2 (REX-BRD9033 or REX-BRD9034)
The Central Processing Unit is responsible for overall control of a DCT1900 system. It contains
two standard I/O ports (RS232) and synchronization ports. One CPU board is required per RE.
The CPU/CPU2 performs the following tasks:
z System initialization
z Call processing
z Intra system mobility management
z System testing and fault recovery
z System statistics information
z PWT air interface synchronization
z Short Message Service (SMS) message broadcast