ADC AVIDIA SWD4573I1, User Manual

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Chapter 20: Configuring Subscriber Services
Avidia System Configuration and Management User Manual 387
Adding ADSL Line Profiles
You add ADSL line profiles from the ADSL Line Profile Table window.
1 In the Rate Mode box, select the desired rate mode ( Fixed Rate or Adapted Rate at Startup ).
The rate mode defines the form of transmit rate adaptation. Fixed Rate means the loop must
be able to come up at the specified maximum transmit rate ( Step 4 ), or it does not come up
at all. Adapted Rate at Startup means the loop will come up at the highest achievable rate that
is greater than the specified minimum transmit rate ( Step 3 ) but less than the specified
maximum transmit rate ( Step 4 ).
2 In the Upstream and Downstream Target Margin boxes, type the target signal-to-noise margin.
This is the noise margin, in decibels/10, that the modem must achieve with a BER of 10
-7
or better to successfully complete initialization. The typical value for the target margin
is 60. A lower target margin may achieve a higher data rate, but increases noise on the line.
3 If you set the Rate Mode to Adapted Rate at Startup, in the Upstream and Downstream Interleave
Min Tx Rate boxes, type the minimum transmit rate for interleave channels in kbps.
Otherwise, skip this step.
This is the guaranteed minimum transmission rate for all lines to which this profile is
applied.
4 In the Upstream and Downstream Interleave Max Tx Rate boxes, type the maximum transmit
rate for interleave channels in kbps.
This is the highest transmission rate to which the modem can adapt for all lines to which
this profile is applied.
5 In the Upstream and Downstream Max Interleave Depth boxes, type the interleave depth in
milliseconds.
The interleave depth specifies the delay between consecutive bytes. Larger delays result in
improved noise immunity, but increase transmission delay. A depth of 16 milliseconds is
ideal for maximum noise immunity. However, a depth of 4 to 6 milliseconds is
recommended to achieve maximum transmission speeds.
6 Click Add to add the ADSL line profile.