Agilent Technologies 8753ET User Manual page 363

Calibrating for Increased Measurement Accuracy
Adapter Removal Using ECal (ES Analyzers Only)
Figure 6-26 Adapters Needed
The following requirements must also be met:
• An ECal module for performing a 2-port error correction for each connector type must be available.
• Specified electrical length of adapter A3 within  1/4 wavelength for the measurement frequency range.
For each port, a separate 2-port error correction needs to be performed to create two calibration sets. The
adapter removal algorithm uses the resultant data from the two calibration sets and the nominal electrical
length of the adapter to compute the adapter's actual S-parameters. This data is then used to generate a
separate third calibration set in which the forward and reverse match and tracking terms are as if port 1 and
port 2 could be connected. This is possible because the actual S-parameters of the adapter are measured
with great accuracy, thus allowing the effects of the adapter to be completely removed when the third
calibration set is generated.
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