Reference Manual

Speech and Data Services
Idle pattern is transmitted.
When both 8 kbps subchannels of a common TS resource go into
idle state they are transformed into one 16 kbps idle resource.
Idle pattern is generated as specified in /GSM:08.54/.
TLS on active subchannel is set On:
•
TCH in ACTIVE state including all sub-states and the channel
mode is not "signalling".
Terrestrial link used for traffic.
Terrestrial link supervision is active.
•
TCH in ACTIVE state including all sub-states and the channel
mode is "signalling".
Idle pattern is transmitted.
Terrestrial link supervision is not active.
TLS on active subchannel is set Off:
For all these cases terrestrial link supervision is not active.
•
TCH in ACTIVE state including all sub-states and the channel
mode is not "signalling".
Terrestrial link used for traffic.
•
TCH in ACTIVE state including all sub-states and the channel
mode is "signalling".
Idle pattern is transmitted.
Idle pattern is generated as specified in /GSM:08.54/.
This function supervises the downlink TRAU frames. The
synchronization bits have to be correct and the received frame type
must be expected.
The synchronization pattern for an idle subchannel is generated either in
the TRA or the BTS (loop). The BTS accepts either one of the
synchronization patterns.
If disturbances on the link result in a long duration of synchronization
and/or frame type errors which exceeds the TLS Filtering Time ( a
configured value) then an error condition is considered present.
When an error condition is present and supervision is On this is
reported to BSC via a FAULT_REPORT message.
If the channel is in ACTIVE state and TLS on active subchannel is On
then a CONNECTION_FAILURE_INDICATION message is sent to
the BSC.
18.3.3 Full Rate Speech
Full Rate Speech is either initiated by the Channel Activation function
or the Mode Modify function.
EN/LZT 720 0008 R1A
2001-06-26
181 (421)
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