beautypg.com

Tektronix CSA8000B User Manual

Page 301

background image

Appendix B: Automatic Measurements Reference

CSA8000B & TDS8000B User Manual

B- 39

Table B- 7: NRZ Measurements - Amplitude (cont.)

Name

Definition

NRZ Crossing %

The height of eye crossing as a percentage of eye height measured in the Eye Aperture.

Where High and Low are the logical 1 and 0 levels, and EyeCross is the level at eye
crossing. See NRZ Eye-Aperture Parameters on page B--65.

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 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 How to Optimize the

Vertical Resolution on page B--70.

NRZ Crossing %

= 100 ×

(Eye Cross

− Low)

(High

− Low)

NRZ Crossing Level

The mean signal level at the eye crossing.

If enabled, measurement gates constrain the measurement region to the area between the Start
Gate (G1) and Stop Gate (G2).

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.

This manual is related to the following products: