VeEX VePal TX130M+, Руководство пользователя

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running.
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24.4.2 Results
The on-screen Wander Measurements include:
Current TIE:
Shows the last Time Interval Error (phase error) measured between the reference clock and the test signal.
Max TIE:
Records the maximum TIE value measured since the test was started.
Min TIE:
Records the minimum TIE value measured since the test was started.
MTIE:
Shows the maximum difference between TIE values measured since the test started (Max - Min)
Note: The wander tests will automatically stop if either of the signals used as reference clock or recovered clock (test signal)
have significant levels of impairments, are lost, or disconnected.
The Graph tab shows the wander behavior for the last 200 seconds for a quick visual verification of stability. Press the Stop
button to terminate the test. If Save TIE to USB is set to ON, then remove the USB memory stick from the test set, bring it to a
computer, and open it with the VeEX Wander Analysis PC software, for further MTIE, TDEV, and masks analysis (refer to the
MTIE and TDEV Analysis section).
Both, Wander Analysis and MTIE / TDEV Post Analysis are optional features.
Reference Clock Wander Analysis Setup and Result
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24.5 1PPS Phase Analysis
Phase Measurement is included with the Clock Wander Analysis option . The option shows as 1PPS Phase Analysis in the
Additional Tests Menu.
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24.5.1 Overview
Reference Clocks have to be highly stable and accurate. Since 1PPS represents the Standard Second around the world, it is
required to be accurate in frequency and phase. Wander measurements give a good indication of the 1PPS Clock frequency
stability over time and also provide a good measurement of the 1PPS Clock accuracy. Very small levels of frequency offset can
be identified and measured, based on TIE data.
Phase Error measurement give a very good indication of the 1PPS Clock’s phase accuracy. It indicates how well it is aligned with
the standard second (UTC).
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