Menu Descriptions
61247004L1-5A
21
A measure of signal quality for each HDSL loop appears on the bottom right and left of the
screen. Guidelines for interpreting the measure indicators are given in
Predicting performance based upon signal quality varies with each loop. Generally, a noise
margin of 0 or higher supports a bit error rate or better the 10
-7
. ADTRAN defined guidelines
that correspond to the operation of the 3192 HTU-C faceplate LEDs labeled LP1 and LP2 are
listed in
.
Table 13. HDSL Loop Signal Quality
Measure
Signal Quality
Noise Margin
0
Poor
≤
0 dB (
≈
10
–7
BER)
1-3
Marginal
above 10
–7
BER in dB
>4
Excellent
≥
4 dB above 10
–7
BER
Table 14. ADTRAN Noise Margin Guidelines
Margin
LP1/LP2 LED
Loop Quality
Margin = 0
z
Red
Poor Loop Quality
0 < Margin < 4
z
Yellow
Marginal Loop Quality
Margin > 4
z
Green
Good Loop Quality
