Manual Part 7
RBS 2000Glossary
Local mode When the RU is in Local mode, it is not communicating
with the BSC.
Local/Remote
switch
A switch used by the operator to order the RU to enter
Local or Remote mode.
LOF
Loss Of Frame
Logical Channel
A logical channel represents a specified portion of the
information carrying capacity of a physical channel.
GSM defines two major categories of logical channels:
• TCHs – Traffic CHannels, for speech or user data
• CCHs – Control CHannels, for control signalling
⇒ Physical Channel ⇒ Channel Combination
Logical RU
A unit which can be referred to, but is not a single
physical unit. There are three different kinds of logical
RUs:
• Antennas
• Buses
• Environment
LOS
Loss Of Signal
LVD
Low Voltage Directive
LVF
Low Voltage Filter
MAC
Medium Access Controller
MADT
Mean Accumulated DownTime
magazine
A magazine is a reserved space in the cabinet, which
may hold one or more RUs.
Main RU Contains one or more processors, to which software
can be downloaded from the BSC. A Main RU is either
Central (CMRU) or Distributed (DMRU). A Main RU
may or may not have a direct signalling link to the BSC.
Main RU A main replaceable unit is a replaceable unit that
contains on
e or more processors, to which software can
be downloaded from the BSC.
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