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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.