XRT75R03D_06 Datasheet, PDF (119/135 Pages) Exar Corporation – EXAR DATA SHEET FORMAT TEMPLATES

XRT75R03D
REV. 1.0.4
THREE CHANNEL E3/DS3/STS-1 LINE
Telcordia GR-253-CORE defines an "87-3 Continuous" Pointer Adjustment pattern, as a repeating sequence
of 90 pointer adjustment events. Within this 90 pointer adjustment event, 87 pointer adjustments are actually
executed. The remaining 3 pointer adjustments are never executed. The spacing between individual pointer
adjustment events (within this scenario) can range from 7.5ms to 10seconds.
Telcordia GR-253-CORE mandates that the Intrinsic Jitter, within the DS3 signal that is de-mapped from a
SONET signal, which is experiencing the "87-3 Continuous" pattern of Pointer Adjustments, must not exceed
1.0UI-pp.
10.5.6 87-3 Add
Figure 53 presents an illustration of the "87-3 Add Pattern" Pointer Adjustment Scenario per Telcordia GR-253-
CORE.
FIGURE 53. ILLUSTRATION OF THE 87-3 ADD POINTER ADJUSTMENT PATTERN
Added Pointer Adjustment
43 Pointer Adjustments
43 Pointer Adjustments
No Pointer
Adjustments
T
t
Telcordia GR-253-CORE defines an "87-3 Add" Pointer Adjustment, as the "87-3 Continuous" Pointer
Adjustment pattern, with an additional pointer adjustment inserted, as shown above in Figure 53.
Telcordia GR-253-CORE mandates that the Intrinsic Jitter, within the DS3 signal that is de-mapped from a
SONET signal, which is experiencing the "87-3 Add" pattern of Pointer Adjustments, must not exceed 1.3UI-
pp.
10.5.7 87-3 Cancel
Figure 54 presents an illustration of the 87-3 Cancel Pattern Pointer Adjustment Scenario per Telcordia GR-
253-CORE.
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