Reference Manual

Channel Distribution Function
configuration commands consist of a number of connections between
timeslots in the Transport network, the Concentrator and the TRXs.
Configuration includes set-up of new connections and release of
connections no longer required. Connections which are the same in the
old and the new configuration are left undisturbed.
Idle pattern is transmitted on unoccupied timeslots in the transport
network interface. An unoccupied timeslot is a timeslot which has no
channel assigned to it. The idle pattern is 01010100 for a 2 Mbit/s
system and 01111111 for a 1.5 Mbit/s system.
If the timeslot is partly used, an idle pattern will be used for all
unoccupied 16 kbit/s subtimeslots within that timeslot. The subslot idle
pattern is 01 for 2 Mbit/s systems and 11 for 1.5 Mbit/s systems.
Maximum capacity (Transport Network Interface) is 62 (2x31) timeslots
for a 2 Mbit/s system and 48 (2x24) timeslots for a 1.5 Mbit/s system.
This corresponds to two PCM lines.
One signalling channel can be switched to each TRX, the capacity of
this channel is 16, 32 or 64 kbit/s.
Eight 16 kbit/s traffic channels can be switched to each TRX, i.e. one
for each available ATSR.
24 signalling channels can be switched to the concentrator, the capacity
of each channel is 64 kbit/s.
The physical mapping, which is needed to configure the switch, is based
on ICPs. Each ICP represent a 16 kbit/s subrate connection point.
The ICPs in the range 4—255 defines the incoming PCM timeslots
according to the table below. The ICPs for timeslots 25—31 are only
valid for 2 Mbit/s systems.
Table 150
ICP Usage
4-7 PCM-A TS1
8-11 PCM-A TS2
... ... ....
122-127 PCM-A TS 31
132-135 PCM-B TS 1
136-139 PCM-B TS 2
... ... ...
250-255 PCM-B TS 31
The range 256—351 defines the concentrator.
The ranges 512—575 and 640—711 define the TRXs.
Table 151
TRX Signalling Traffic
0 512-515 516-523
1 524-527 528-535
2 536-539 540-547
EN/LZT 720 0008 R1A
2001-06-26
377 (421)
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