Terminal Auxiliary Data And Alarm I/O; Operation; Atpc; Fec - Alcatel-Lucent 9500 MXC User Manual

Terminal Auxiliary Data and Alarm I/O

Operation

ATPC

FEC

3DB 23063 ADAA - Rev 004 July 2007
All Terminals support auxiliary data and alarm I/O:
• The data interface supports one 64 kbps synchronous or one 19.2 kbps (1.2 to
19.2 kbps) asynchronous channel.
• The alarm I/O supports two TTL alarm inputs and four Form C relay outputs.
Advanced operational features include:
• ATPC
• FEC
• Adaptive Equalization
• Tx Power Management
Automatic Transmitter Power Control (ATPC) for the 9500 MXC Node and
Terminal is configurable over their full dynamic range in 0.1 dB steps. ATPC is
enabled/disabled through 9500 MXC CT, with the operator able to select a target
fade margin, and low and high transmit power limits.
All RACs and IDUs employ Reed-Solomon FEC encoding (with interleaving).
RAC 3X, RAC 40, IDU ES and IDU 155o also incorporate Viterbi encoding on
selected capacity/modulation options.
Reed-Solomon FEC code is utilized to typically correct up to 8 errored bytes per
250/255 byte block (frame). This improves the receiver 10
approximately 3 dB. Actual block size is dependent on the selected capacity for
the link.
Immunity to burst noise is enhanced by an interleaving function, which spreads
burst errors evenly over the blocks, reducing the number of errors per block, and
improving the ability for the FEC to correct induced errors. The amount of
interleaving performed is dependent on the transmission capacity, to be over 2 or
4 blocks.
Viterbi is most suited to channels where signal corruption is caused by additive
white (gaussian) noise, which is particularly relevant near receive thresholds
9500 MXC User Manual
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threshold by
Vol. II-6-7