Setting Limit For Constellation; Measurement Example - JDS Uniphase CellAdvisor JD780A Series User Manual

NOTE
The Delay setting is used only when there is a time offset in the signals to be measured.

Setting limit for constellation

Procedure
1.
Press the LIMIT hot key.
2.
Press the Modulation Test Limits soft key to set the limits in the Constellation measurement.
3.
Select the test item(s) and set the limit(s) depending on your selected measurement mode:
To set the limit for
Frequency error
Phase error rms
Phase error peak
Error vector magnitude rms
Error vector magnitude peak
I/Q origin offset of the I and Q error
(magnitude squared) offset from the origin
Carrier to interference (C/I) ratio
4.
Optional. You can enable alarm sound that goes off if the measurement falls outside of the limit.
Toggle the Beep soft key between On and Off to enable or disable the beep sound.
5.
Optional. Go to SAVE/LOAD > Save, and then select Limit to save the limit settings.
See "Using save" on page 31 for more information.

Measurement example

Figure 47 Constellation measurement with GSM signal analyzer
Select
Frequency Error
Phase Error RMS
Phase Error Peak
EVM RMS
EVM Peak
IQ Origin Offset
C/I
Using GSM/GPRS/EDGE Signal Analyzer
JD780A Series Analyzers
Set
High Limit, Low Limit
High Limit, Low Limit
High Limit, Low Limit
High Limit
High Limit
High Limit
Low Limit
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