Service Manual

GSM-204-323
Cage backplane interface panel harness assembly (CBIA)
31st Oct 01
Technical Description: Horizon macro outdoor
68P02902W02-A
CONTROLLED INTRODUCTION
Tech. 2–13
CBIA backplane
function
The cabinet design enables all possible RF and digital module combinations to
be served by the same backplane. The only module-to-module cabling required
within the radio enclosure are the Tx cables from the transceivers to the Tx
blocks.
The backplane is a multilayered printed circuit board with attached connectors
on front and back. The backplane:
 Routes power and digital signals throughout the cabinet.
 Provides connectors for the harness cables linking to the interface panel.
 Provides connectors for plug in modules.
 Provides power to the SURF harness, when the main cage is inserted into
the cabinet.
 Provides a connector for the door switch cable.
 Provides connectors for three heat sensors in the main cage above the
CTUs.
 Provides a connection (Fan 0) for the TMS fan fail alarm cable.
Attachment of
cage to cabinet
The CBIA is fitted to the cabinet at the factory and is not intended to be
removed in the course of normal maintenance or FRU replacement procedures.