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Concepts and Features
R&S
®
ZNB/ZNBT
212
User Manual 1173.9163.02 ─ 55
●
Opening Factor
This is a measure of the effects of amplitude noise on the vertical eye opening.
Accordingly, it is equal to
(("Eye Top" - σ
Top
) - ("Eye Base" + σ
Base
)) / "Eye Amplitude"
●
SNR
Relates the "Eye Amplitude" to the noise level. Accordingly, it is equal to
"Eye Amplitude" / (σ
Top
+ σ
Base
)
Eye diagram results are only available for NRZ modulated signals.
Eye Mask Test
Furthermore, the eye diagram simulation allows to perform tests against a user-defined
eye mask:
Figure 5-16: User-defined Eye Mask
Eye mask tests are only available for NRZ modulated signals.
Rise Time Measurement
From the measured S parameters, the step responses can also be calculated using the
inverse Fourier transform. The rise time is the time the step response takes to rise from
x% to y% (0≤x≤y≤100) of the resulting step size, typically from 10% to 90%.
Optional Extensions and Accessories