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S-4
Specifications
PDH MUX/DEMUX
ANT-20/ANT-20E
2
Receiver section
2.1
Frame systems
Frames which can be evaluated by the 64k/140M PDH MUX/DEMUX chain and
64k/140M PDH DEMUX chain (options BN 3035/90.30 and 3035/90.31)
All timeslots can be selected for all PCM frame structures. These may be speech or data
channels in a primary rate system or the tributary channels in a justified multiplex system.
2.2
Evaluation
2.2.1
Frame bit evaluation
The following bits are evaluated and displayed:
For PCM30/31 CRC systems, one of the bits S
a
4 through S
a
8 can be selected in order to
display pattern sequences of up to 8 bits in length.
The D alarm bits (RDI alarms) are also evaluated and indicated by means of LEDs.
Also see in the ”Specifications” of the mainframe instrument.
2.2.2
CRC evaluations (PCM 30 CRC / PCM 31 CRC)
Errored CRC words are evaluated in the selected channel (CRC word error count).
The equivalent CRC bit error ratio is calculated from the CRC word error ratio.
The number of E bit errors is also converted to the equivalent bit error ratio.
Bit rate kbit/s
Frame conforming to
Notes
2048
ITU-T G.704
PCM 30, PCM 31 systems
2048
ITU-T G.704/G.706
PCM 30 CRC, PCM 31 CRC systems
8448
ITU-T G.742
PCM 120 system
34368
ITU-T G.751
PCM 480 system
139264
ITU-T G.751
PCM 1920 system
Table S-4
Frame systems for individual system bit rates
PCM 1920 (G.751) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .FAS bit nos. 13, 14, 15, 16
PCM 480, 120 (G.751, G.742). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FAS bit nos. 11, 12
PCM 30/31 (G.7049) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . NFAS bit nos. 1 through 8
PCM 30/31 CRC (G.704). . . . . . . . . . . . . . . NFAS bit nos. 2 through 8 (A bit, S
a
4 through S
a
8)