Tektronix CSA8000B, TDS8000B B-40 CSA8000B & TDS8000B User Manual

Appendix B: Automatic Measurements Reference
B-40 CSA8000B & TDS8000B User Manual
Table B- 7: NRZ Measurements - Amplitude (cont.)
Name Definition
NRZ Extinction Ratio The ratio of the average power levels of the logic 1 level (High) to the logic 0 level (Low) of an
optical NRZ signal. All level determinations are made within the NRZ Eye Aperture.
Where High and Low are the logical 1 and 0 levels.
The Eye Aperture is adjustable and defaults to 20% of the NRZ bit time. 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). 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 measurement results:
HPerform a Dark Level compensation before taking this measurement. See To Perform
Dark-Level and User Wavelength Gain Compensations on page 3--98.
HOptimize the vertical resolution before taking this measurement. See How to Optimize the
Vertical Resolution on page B--70.
NRZ ExtRatio =100 ×ᏋLow
HighᏐ
NRZ Extinction Ratio (%) The ratio of the average power levels of the logic 0 level (Low) to the logic 1 level (High) of an
optical NRZ signal, expressed as a percentage. All level determinations are made within the
NRZ Eye Aperture.
Where High and Low are the logical 1 and 0 levels.
The Eye Aperture is adjustable and defaults to 20% of the NRZ bit time.
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 measurement results:
HPerform a Dark Level compensation before taking this measurement. See To Perform
Dark-Level and Gain User Wavelength Gain Compensations on page 3--98.
HOptimize the vertical resolution before taking this measurement. See To Optimize the
Vertical Resolution on page B--69.
NRZ ExtRatio [%] =100 ×ᏋLow
HighᏐ