User Manual

ArchitectureNortel Networks Confidential 3–35
S8000/S8002/S8006 BTS Reference Manual
Configuration
The DRX is configured by the BSC by means of an OML link on the Abis interface.
Configuration can be broken down into:
a general configuration:
• configuration of the TDMA frame
time slot configurations:
• configuration of radio time slots
• configuration of the frequency hop
Configuration of the TDMA frame provides the DRX with parameters shared by
the whole cell, such as:
cell identity (BSIC)
BCCH frequency
indication of frequency hopping implementation
cell type (normal or extended)
and with parameters specific to the DRX:
the frequency of the TDMA frame if there is no frequency hopping
indication of implentation of diversity in reception
The TDMA frame cannot be dynamically configured. A change of configuration
requires re–start of the downloaded software.
The configuration of the radio time slot specifies the type of logical channel to use
for a time slot.
The configuration of the frequency hopping specifies, for a time slot, the list of
frequencies to use, as well as sequencing. This configuration is optional and only
appears if the frequency hopping was requested in the TDMA frame configuration.
Monitoring
The BSC regularly sends status requests to the DRX to detect any problems on the
OML link.
LAPD break
The LAPD, OML and RSL links are monitored by a timer. If level 2 loss is detected,
the BSC and the AMNU try to reconnect. If connection has not been made by the
end of the time–out, the AMNU is reinitialized.