Service Manual

GSM-205-323
Overview of digital modules
31st Oct 01
Tech. 6–2
Technical Description: Horizon macro indoor
CONTROLLED INTRODUCTION
68P02902W07-B
MCUF and NIU
redundancy
The digital module shelf can:
 Support two MCUFs at a BTS site, one master and one slave (for
redundancy).
 Enable Master MCUF failure to result in the slave MCUF becoming the
master after reset.
 Enable the OMC-R operator to initiate master/slave MCUF swap.
 Configure CTUs by the master MCUF.
All four NIUs operate from the master MCUF, but each pair of NIUs depend on a
BPSM for power. All NIUs configure to the master MCUF clock.
NOTE
When fitting a replacement redundant MCUF, care must
be taken to ensure firmware compatibility with the master
MCUF. Firmware incompatibility may result in a loss of
communication between the two MCUFs so that the
redundant MCUF is not in a position to take control in the
event of a failure of the master MCUF.
Full size and
half size
modules
Modules are full size and half size, as shown in Table 6-1.
Table 6-1 Full size and half size digital modules
Full size modules Half size modules
Main Control Unit with dual FMUX (MCUF) Network interface unit (NIU)
Alarm module Fibre optic multiplexer (FMUX)
BPSM (µBCU Power Supply
Module)