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Description
553-3001-105
Standard 5.00
June 1999
Digital line interface units
The NT8D02 and QPC578 digital line cards provide voice and data
communication links between a Meridian 1 switch and modular digital
telephones. These lines carry multiplexed PCM voice, data and signaling
information as time compression multiplexed (TCM) loops. Each TCM loop
can be connected to a Nortel Networks “Meridian Modular Digital” telephone
set.
The digital line interface card contains one or more digital line interface units
(Figure 11). Each digital line interface unit contains a digital line interface
circuit (DLIC). The purpose of each digital line interface circuit is to
demultiplex data from the DS-30X Tx channel into integrated voice and data
bitstreams and transmit those bitstreams as Bi-Polar Return to Zero, Alternate
Mark Inversion (BPRZ-AMI) data to the TCM loop. It also does the opposite:
receives BPRZ-AMI bitstreams from the TCM loop and multiplexes the
integrated voice and data bitstream onto the DS-30X Rx channel.
Figure 11
Digital line interface unit block diagram
4-wire
to
2-wire
conversion
Digital
line
interface
circuit
TCM loop
interface
and
protection
Tip
Ring
DS-30X loop
Tx PCM
1 kHz frame
sync
Rx PCM
553-6154
±15 V dc power supply
Содержание NT1R20
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Страница 154: ...Page 130 of 290 NT5D11 Line side T1 Interface Card 553 3001 105 Standard 5 00 June 1999 ...
Страница 216: ...Page 192 of 290 NT5D33 and NTRB34 Line side E1 Interface Cards 553 3001 105 Standard 5 00 June 1999 ...
Страница 264: ...Page 240 of 290 QPC192 Off Premise Extension OPX Analog Line Card 553 3001 105 Standard 5 00 June 1999 ...
Страница 276: ...Page 252 of 290 QPC452 Basic 500 2500 Analog Line Card 553 3001 105 Standard 5 00 June 1999 ...
Страница 302: ...Page 278 of 290 QPC789 16 port Message Waiting Analog Line Card 553 3001 105 Standard 5 00 June 1999 ...
Страница 306: ...Page 282 of 290 List of terms 553 3001 105 Standard 5 00 June 1999 ...
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