Other topics about Advanced Calibration
To perform 8-term error model calibration using an external PC (measuring raw measurement data using the E5072A, calculating error term using external PC and then performing correction with calculated error terms and measured raw data), the procedure described in this section must be followed. When you use this method, the measurement specification is not satisfied.
In most cases, users do NOT need to follow the below procedure as these considerations have already been performed on 8-term error model calibration in E5072A.
When users perform 12-term error model calibration using external computer such as SOLT calibration, users do NOT need to perform the following procedure.
In its default setting, the E5072A applies "system correction" to the measured S-Parameter data. As the "system correction" is applied only to the S-Parameter measurement data and not to the absolute value measurement data, it interferes with 8-term error model calibration when calculating error coefficients on the external computer. You need to turn OFF this state all the time for calibration and measurement.
The system calibration can be turned OFF by:
System > Service Menu > System Correction
The setting of system correction is kept until preset. This state is saved in the state file.
There is a source attenuator offset correction function on E5072A. The default setting of this state is ON, and this state interferes with 8-term error model calibration when calculating error coefficients on external computer. You need to turn OFF this state, all the time for the calibration and the measurement.
The source attenuator offset correction can be turned OFF by:
System > Service Menu > Offset Correction for Source Atten.
The setting of source attenuator offset correction is kept after preset. This state is NOT saved in the state file.
Assume that you perform 2-port TRL calibration on channel1, you need to send following command before calibration. Also, you need to keep this state all the time for calibration and measurement.
SYST:CORR:STAT OFF ' (SCPI) system correction off
SYST:CORR:OFF:SOUR:STAT OFF ' (SCPI) source attenuator offset correction off