Tektronix CSA8000B, TDS8000B CSA8000B & TDS8000B User Manual B-19

Appendix B: Automatic Measurements Reference

CSA8000B & TDS8000B User Manual B-19

Table B- 4: RZ Measurements - Amplitude (cont.)

Name Definition

RZ Eye Opening Factor RZ Eye Opening Factor is a measure of how noise affects the vertical opening between High

and Low levels of an RZ pulse. The RZ pulse is sampled within the Eye Aperture, where the

High and Low levels are determined as the mean of the histogram of the data distribution in the

upper and lower half of the pulse, respectively. The noise levels are characterized by σhigh and

σlow, the standard deviations from the mean for the High and Low levels.

Where High and Low are the logical 1 and 0 levels, and σhigh and σlow are the standard

deviations. See RZ Eye Aperture Parameters on B--62.

The Eye Aperture is adjustable and defaults to 5% of the RZ pulse width.

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:

HPerform 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.

HOptimize the vertical resolution before taking this measurement. See To Optimize the

Vertical Resolution on page B--69.

RZ Eye Opening Factor =Ꮛ(High −σhigh)−(Low +σlow)

(High −Low)Ꮠ

RZ Gain RZ Gain is a defined as the amplitude gain between two waveforms. The measurement returns

the ratio between the amplitudes measured within the Eye Aperture of each of the waveforms.

Where Ampl1 and Ampl2 are the amplitudes of the two source waveforms.