Huawei ATN 950B Hardware Description page 79

ATN 950B Multi-service Access Equipment
Hardware Description
Figure 5-14
Figure 5-14 Functional block diagram of the AND3ML1A/AND3ML1B
Transmit Direction
The service signals from the AND1CXPA/AND1CXPB are sent to the service processing
module. The service processing module performs PWE3 decapsulation and PW scheduling for
the service signals, processes the service signals based on the IMA/ATM, CES, and ML-PPP
protocols, performs the E1 framing function, and sends the service signals to the service access
module. The service access module performs encoding and line drive for the signals and outputs
the signals through the backplane-side interfaces.
Receive Direction
The board accesses service signals through the backplane-side interfaces, and then the signals
are sent to the service access module. The service access module performs interference isolation,
lightning-proof, impedance matching, level conversion, signal balancing, decoding, and then
sends the processed signals to the service processing module. The service processing module
performs E1 framing, processes service signals based on the IMA/ATM, CES, and ML-PPP
protocols, implements PWE3 encapsulation and PW scheduling, and sends the signals to the
AND1CXPA/AND1CXPB through the backplane-side interfaces.
Service Access Module
This module performs the following functions:
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Issue 03 (2012-07-23)
shows the functional block diagram of the AND3ML1A/AND3ML1B.
16 x E1
Service access
module
Line clocks
Clock
module
Line clocks
In the receive direction, this module isolates common mode interference, protects circuits
against transient failures, matches the impedance in the receive direction with the internal
impedance, and performs level conversion, balancing, and decoding for the service signals.
Finally, this module sends the processed signals to the service processing module.
In the transmit direction, this module receives the service signals from the service
processing module, encodes the signals, drives the line, and outputs the service signals
through the backplane-side interfaces.
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Service signal Service
processing
module
Management bus
Management
module
3.3V
Power
. .
. .
supply
. .
module
1V
5 Physical Interface Card
Backplane
Service signal
Management bus
-48V/-60V
-48V/-60V
System clocks
CXP
CXP
System
power supply
System
power supply
CXP
CXP
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