Reference Manual

Glossary
LED Light Emitting Diode
LLB Line Loop Back
LNA Low Noise Amplifier
Local bus The local bus offers communication
between a central main RU (DXU) and
distributed main RUs (TRU and ECU).
Local mode When the RU is in RU mode Local it is
not prepared for BSC communication.
Local/Remote switch Using the Local/Remote switch, an
operator orders 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:
1. Buses
2. Antennas
3. Environment
LOS Loss Of Signal
MAC Medium Access Controller
Magazine A magazine is a reserved space in the
cabinet, which may hold one or more RUs.
Main RU A main replaceable unit is a replaceable
unit that contains one or more processors,
to which software can be downloaded
from the BSC.
MHS Modification Handling System
Ericsson trouble report database
414 (421)
EN/LZT 720 0008 R1A
2001-06-26
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