Tektronix OM4006D, Руководство пользователя

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Operating basics
Table 11: OUI: Analysis Parameters window (cont.)
Parameter Description
Chromatic Dispersion The value of Dpsnm used by the Compensate CD function in
ps/nm. The sign of Dpsnm should be the same as that of the
dispersion compensating
fi ber that it replaces. In other words,
Compensate CD is a dispersion compensator with dispersion
of Dpsnm.
Compensate CD Applies a mathematical model to remove Chromatic Dispersion
(CD). The mathematical model used for the
fi lter is:
H( ω ) = e
i ωβ
2
/2
,
where
PMD Polarization Mode Dispersion (PMD) measurement. (See
page 52,
PMD measurement .)
Use signal description
from of
fl ine fi le
When selected, applies signal description parameters (signal
type, clock frequency, data content) taken from of
fl ine fi le. When
not selected, applies parameters from Analysis Parameters.
This control has no effect when processing live data.
Use front end fi lter from
of fl ine fi le
When selected, applies front end fi lter parameters taken from
of fl ine fi le. When not selected, applies parameters from Analysis
Parameters.
This control has no effect when processing live data.
Use calibration from
of
fl ine fi le
When selected, applies calibration data (hybrid, equalization
calibration) taken from of
fl ine fi le. When not selected, applies
calibration data loaded from disk at OUI startup.
This control has no effect when processing live data.
Use carrier de fi nition
table from of fl ine fi le
When selected, applies multicarrier carrier de fi nition table taken
from of fl ine fi le. When not selected, applies current carrier
de fi nition table in Multicarrier Setup window.
This control has no effect when processing live data.
Data Content For error counting, constellation orientation, and two-stage
phase estimation, the data pattern of each tributary must be
speci
fi ed. Omitting the data speci fi cation or providing incorrect
information about your data pattern will not stop the constellation
or eye displays except that there will be no consistent
identi
fi cation of each tributary since the identi fi cation of I and Q
and X and Y is arbitrary in the case where the data is not known.
Identify your data patterns for each tributary by choosing a
standard PRBS from the drop-down menu, or by assigning
the pattern variable directly. Select a user pattern from the
drop-down menu before assigning the variable directly.
OM4000D Series Coherent Lightwave Signal Analyzer 37