Service Manual

GSM-205-323
FMUX module
31st Oct 01
Tech. 6–22
Technical Description: Horizon macro indoor
CONTROLLED INTRODUCTION
68P02902W07-B
FMUX module
Overview of
FMUX module
The fibre optic multiplexer (FMUX) module multiplexes and demultiplexes six,
full duplex, transceiver links to one (TX/Rx) pair of fibre optic cables. This
enables up to six transceivers in a single extension cabinet (either
Horizon
macro or M-Cell 6 ) to be linked to the master cabinet.
The FMUX module has two modes of operation:
 Working in conjunction with the MCUF to multiplex transceiver links to/from
a third extension cabinet.
 Operating in the extension cabinet to supply the transceivers in that
cabinet.
To enable a total of four cabinets to be joined together as one BTS site, an
FMUX module is required in the master cabinet to connect the third extension
cabinet. A single cabinet site has no need for an FMUX module, because the
MCUF connects with the cabinet CTUs through the backplane.
Two FMUX modules may be fitted in the digital module shelf, one for the master
MCUF, and one for the slave. An extension cabinet only requires one FMUX to
connect to six transceivers within the cabinet, (plus one for redundancy if
required).
Each FMUX fibre optic link is full duplex 16.384 Mbit/s. The FMUX optical link is
capable of driving up to 1 km.
FMUX module
view
Figure 6-8 shows an FMUX module.
BACKPLANE
CONNECTOR
FIBRE OPTIC INPUT FROM
ANOTHER MCUF/FMUX IN
ANOTHER CABINET AT THE SITE
FIBRE OPTIC OUTPUT TO
ANOTHER MCUF/FMUX IN
ANOTHER CABINET AT THE SITE
Figure 6-8 View of the FMUX module