Even-Odd (F/2) Result

Meas. mode:
Jitter
Waveform type:
NRZ
PAM4

Click the Measurement (Meas) toolbar's F/2 to activate The Jitter mode F/2 jitter (J(F/2)) measurements, also known as even-odd jitter (J(even-odd). F/2 occurs as the result of timing data with a half-rate clock. If the clock is asymmetric then even symbols versus odd symbols will differ in length from nominal. F/2 jitter is measured as the absolute value of the difference between the even and odd symbols in seconds as a peak-to-peak value:

J(F/2)) = | (symbol_periodeven − symbol_periododd) / 2 |

The following figure shows an eye diagram in which blue and orange colors identify the portions of an eye that are created with the signal's even or odd symbols. This is one signal; the colors do not represent different scope channels. The eyes, formed by the even and odd symbol periods, are overlayed on top of each other with example symbol periods of 90 ps and 110 ps. In this example, the F/2 jitter measures 10 ps.

If the F/2 jitter measurement is already listed on the Results table, it is moved to the top of the table. The query form of the command returns the measured value. This measurement is only available in Jitter Mode. When measuring a simulated waveform, the pattern length in pattern lock setup must be set to an even number by doubling the pattern length setting in the simulator. On real signals the user must be responsible for assuring that the pattern is consistent with any measurement standard requirements.

More Information

SCPI Command

:MEASure:JITTer:FOVer2