PM73121ꢀAAL1gator II
Data Sheet
PMC-Sierra, Inc.
PMC-980620
,VVXHꢀꢁ
AAL1 SAR Processor
8.10.4 SRTS E1 Clock
15
The E1 SRTS clock jitter was measured using a 2 -1 PRBS pattern in unstructured mode.
Two AAL1gator IIs were connected to each other across a point-to-point ATM connection. One
AAL1gator II was used to generate SRTS values, and the other AAL1gator II was used to receive
the values. The source AAL1gator II was connected to a FIREBERD, which used an external
signal generator as its clock source. The clock source was stepped across the entire ± 90 ppm
range and the jitter was measured at the FIREBERD connected to the AAL1gator II at the
receiving end. A jitter spectrum was then taken at the frequency that exhibited the worst jitter.
The total maximum jitter without the jitter attenuator was 0.845 UI. With a jitter attenuator the
maximum jitter was 0.42 UI. See Figure 104 through Figure 107 on page 193 for jitter versus
frequency and the jitter spectrum versus the G.824 mask.
2
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
2047700 2047800 2047900 2048000 2048100 2048200 2048300
Frequency +/- 100 ppm
Figure 104. Maximum E1 SRTS Jitter with no Jitter Attenuator
ꢀꢈꢀ
PMC [ PMC-SIERRA, INC ]
