Appendix B: Automatic Measurements Supported
B-4
CSA7000B Series & TDS7000B Series Instruments User Manual
Table B- 2: Comm measurements and their definition
Name Definition
Ext Rati o The ratio of eye top to base.
Ext Ratio = PTop
m
an
/PBase
m
an
Extinction Ratio % The ratio of eye base to top in %.
Ext Ratio % = 100*(PBase
m
an
/PTop
m
an
)
.
Ext Ratio dB = 10*Log(PTop
m
an
/PBase
m
an
)
Eye Height The eye height in watts or volts.
Eye Height = (PTop
m
an
-- 3*PTop
si
ma
) -- (PBase
m
an
+ 3*PBase
si
ma
)
Eye Width The eye width in seconds.
Eye Width = (TCross2
m
an
-- 3*TCross2
si
ma
) -- (TCross1
mean
+ 3*TCross1
si
ma
)
Crossing % The eye crossing point as a percentage of eye height.
Crossing % = 100*[(PCross1
mean
-- PBase
mean
)/(PTop
mean
-- PBase
mean
)]
Eye Top The top of the eye.
Eye Base The base of the eye.
Jitter Pk- Pk The peak-to-peak value for the edge jitter in the current horizontal units.
Jitter PP = TCross1
Jitter RMS The RMS value of the edge jitter in the current horizontal units.
Jitter RMS = TCross1
sigma
Jitter 6σ 6 x (Jitter RMS)
Noise Pk-Pk The peak-to-peak value of the noise of the top or base of the signal as specified by the
.
Noise Pk--Pk = PTop
pk--pk or
PBase
pk--pk
Noise RMS The RMS value of the noise of the top or base of the signal as specified by t he user.
Noise RMS = PTop
si
ma
PBase
si
ma