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XRT75L00D Datasheet, PDF (74/92 Pages) Exar Corporation – E3/DS3/STS-1 LINE INTERFACE UNIT WITH SONET DESYNCHRONIZER
XRT75L00D
E3/DS3/STS-1 LINE INTERFACE UNIT WITH SONET DESYNCHRONIZER
REV. 1.0.2
TABLE 18: SUMMARY OF "CATEGORY I INTRINSIC JITTER REQUIREMENT PER TELCORDIA GR-253-CORE, FOR DS3
APPLICATIONS
SCENARIO
DESCRIPTION
SCENARIO
NUMBER
TELCORDIA GR-253-CORE
CATEGORY I INTRINSIC
JITTER REQUIREMENTS
COMMENTS
Continuous Add
A5
1.3UI-pp
Includes effects of Jitter from Clock-Gapping, De-Map-
ping and Pointer Adjustments.
Continuous Cancel
A5
1.3UI-pp
Includes effects of Jitter from Clock-Gapping, De-Map-
ping and Pointer Adjustments.
NOTE: All of these intrinsic jitter measurements are to be performed using a band-pass filter of 10Hz to 400kHz.
Each of the scenarios presented in Table 18, are briefly described below.
9.5.1 DS3 De-Mapping Jitter
DS3 De-Mapping Jitter is the amount of Intrinsic Jitter that will be measured within the "Line" or "Facility-side"
DS3 signal, (after it has been de-mapped from a SONET signal) without the occurrence of "Pointer
Adjustments" within the SONET signal.
Telcordia GR-253-CORE requires that the "DS3 De-Mapping" Jitter be less than 0.4UI-pp, when measured
over all possible combinations of DS3 and STS-1 frequency offsets.
9.5.2 Single Pointer Adjustment
Telcordia GR-253-CORE states that if each pointer adjustment (within a continuous stream of pointer
adjustments) is separated from each other by a period of 30 seconds, or more; then they are sufficiently
isolated to be considered "Single-Pointer Adjustments".
Figure 48 presents an illustration of the "Single Pointer Adjustment" Scenario.
FIGURE 48. ILLUSTRATION OF SINGLE POINTER ADJUSTMENT SCENARIO
Pointer Adjustment Events
>30s
Initialization
Cool Down
Measurement Period
Telcordia GR-253-CORE states that the Intrinsic Jitter that is measured (within the DS3 signal) that is
ultimately de-mapped from a SONET signal that is experiencing "Single-Pointer Adjustment" events, must NOT
exceed the value 0.3UI-pp + Ao.
NOTES:
1. Ao is the amount of Intrinsic Jitter that was measured during the "De-Mapping" Jitter portion of this test.
2. Testing must be performed for both Incrementing and Decrementing Pointer Adjustments.
9.5.3 Pointer Burst
Figure 49 presents an illustration of the "Pointer Burst" Pointer Adjustment Scenario per Telcordia GR-253-
CORE.
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