10-32
IM 701310-01E
Explanation
The DL9000 can perform a telecom test, which consists of a mask test and eye pattern
measurement, and display the results. The mask test detects an error if the source
trace enters any of the four masks (elements) that have been created on a PC. For the
procedure to load mask patterns, see section 13.7.
Source Waveform
Select the source waveform from CH1 to CH4 or from M1 to M4.
Measurement Source Window
Select Main, Z1, or Z2.
Time Range
The selectable range is �5 divisions by taking the center of the waveform area to be 0
divisions. The resolution is 0.01 divisions.
Measurement Items
Select the measurement items from the table below.
• Mask Test
Wave Count
Acquisition error count
Wave Count %
Acquisition error rate (%)
Sample Point Count
Sampling error count/total data count
Sample Point Count %
Sampling error rate (%)
• Eye Pattern Measurement
For definitions of measurement items and their formulas, see
“Telecom Test” in section 2.8.
Crossing %
Level where the rising edge and the falling edge of the eye pattern
intersect, expressed as a percentage with respect to the difference
between Vtop and Vbase.
Eye Height
Height of the eye
Eye Width
Width of the eye
Q Factor
Quality factor of the eye diagram expressed as a ratio of the eye
height with respect to the noise at both the high and low voltage
levels.
Jitter
Magnitude of the time fluctuation of the crossing point
Duty Cycle Distortion %
Time difference between the falling edge intermediate point and
the rising edge intermediate point determined by the intermediate
threshold level, expressed as a percentage with respect to the full bit
width.
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
Average time of the first crossing point
Tcrossing2
Average time of the second crossing point
Vcrossing
Voltage where the rising edge and the falling edge cross
Ext Rate dB
Extinction rate dB
Rise
Rise time from the specified lower threshold level to the upper
threshold level
Fall
Fall time from the specified upper threshold level to the lower
threshold level
Upper and Lower Threshold Levels
Set the threshold levels in percentage or by using physical values. Threshold level
settings are used to measure the eye pattern rise and fall items.
V
You can set the level within �10 divisions. The unit changes depending on the set
conditions.
%
You can set the level from 0 to 100%. The difference between Vtop and Vbase is taken to
be 100%.
10.4 Performing a Telecom Test (Mask Test and Eye Pattern Measurement)
