Tektronix CSA8000B Series, User Manual

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Appendix B: Automatic Measurements Reference
CSA8000B & TDS8000B User Manual
B- 15
Return-to-Zero (RZ) Measurements - Amplitude
Table B--4 describes each RZ measurement in the amplitude category. See Table
on B--5 on page B--29 for timing category measurements; see Table B--6 on page
B--36 for area category measurements.
Table B- 4: RZ Measurements - Amplitude
Name Definition
RZ AC RMS The root mean square amplitude, minus the DC component, of the waveform that is sampled
within the measurement region.
If enabled, measurement gates constrain the measurement region to the area between the Start
Gate (G1) and Stop Gate (G2). See
To Localize a Measurement on page 3--83.
This measurement requires the use of a waveform database. When this measurement is turned
on, it will automatically set the measurement system to use a waveform database if available.
See
Use a Waveform Database on page B--70.
For best results with this measurement:
H
Perform a Dark Level compensation before taking this measurement if the source of the
measured waveform is an optical channel. See
To Perform Dark-Level and User
Wavelength Gain Compensations on page 3--98.
H
Optimize the vertical resolution before taking this measurement. See To Optimize the
Vertical Resolution on page B--69.
RZ Amplitude The difference between the logical 1 level (High) and the logical 0 level (Low) of the RZ signal.
Both High and Low levels are measured within the Eye Aperture.
RZ Amplitude = High – Low
Where High and Low are the logical 1 and 0 levels.
The Eye Aperture is adjustable and defaults to 5% of the RZ pulse width.
See RZ Eye Aperture Parameters on B--62.
If enabled, measurement gates, constrain the measurement region to the area between the
Start Gate (G1) and Stop Gate (G2).
This measurement requires the use of a waveform database. When this measurement is turned
on, it will automatically set the measurement system to use a waveform database if available.
For best results with this measurement:
H
Perform a Dark Level compensation before taking this measurement if the source of the
measured waveform is an optical channel. See
To Perform Dark-Level and User
Wavelength Gain Compensations on page 3--98.
H
Optimize the vertical resolution before taking this measurement. See To Optimize the
Vertical Resolution on page B--69.