2-28
IM 701310-01E
Telecom Test ►For the procedure, see section 10.4
There are two available tests. The mask test is used to analyze the communication
signal. The other test automatically measures the waveform parameters of the eye
pattern.
Measurement is performed on the accumulated waveform when the mode is set to
Count.
In the mask test, a mask pattern created with the software supplied free of charge by
Yokogawa is read into the DL9000, and the waveforms passing through the mask are
counted.
In the eye pattern test, the following items are measured in the eye pattern.
3σcrossing2
3σcrossing1
Eye Width
40%
20%
40%
Vtop
Vbase
3σbase
3σtop
Eye Height
T crossing2
T crossing1
V crossing
Vtop
Vertical histogram top peak average voltage.
Vbase
Vertical histogram bottom peak average voltage.
σ
top
Vertical histogram top peak standard deviation.
σ
base
Vertical histogram bottom peak standard deviation.
Tcrossing1
First crossing point average time value.
Tcrossing2
Second crossing point average time value.
Vcrossing
Voltage at the point of intersection of the rising edge and falling edge.
Crossing %
Level of the point of intersection of the rising edge and falling edge
of the eye pattern as a proportion of the difference between Vtop and
Vbase.
Eye Height
Height of the opening in the eye diagram.
Eye Width
Width of the opening in the eye diagram.
Q Factor
Quality factor for the eye diagram showing the height of the eye
pattern opening, with respect to the noise at both high and low
voltage levels.
Jitter
Magnitude of the fluctuation in the time position of the crossing point.
Duty Cycle Distortion % The percentage of full bit width of time difference between the
intermediate point of the falling edge and the intermediate point of the
rising edge at the intermediate threshold value.
Ext Rate dB
Extinction rate dB.
Rise
Rise time from the specified lower to upper threshold level.
Fall
Fall time from the specified upper to lower threshold level.
2.8 Analyzing and Searching