R&S ZNB Series User Manual page 218

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R&S ZNB/ZNBT
Fixture Modeling Process
For all supported tools, the fixture modeling proceeds as follows:
1. Perform a calibration to the fixture connectors.
2. Measure one or more PCB test coupons for the related fixture.
The results are independent of a particular DUT. Hence they can be reused for
subsequent measurements using the same test fixture.
3. Measure the total structure, i.e. the DUT with the fixture.
4. Run the selected third-party tool to calculate the fixture deembedding files.
After a final confirmation, the calculated deembedding files (s2p for single-ended
ports, s4p for balanced ports) are used for deembedding the DUT at the respective
logical port(s).
Test Coupons
The test fixture consists of a set of lead-ins.
Figure 4-14: DUT with Test Fixture (balanced)
The fixture modeling tools require test coupons for the lead-ins to the DUT and that are
either representing a Through, an Open or a Short. If the lead-ins "on the left" and "on
the right" side of the DUT ("lead-outs") are not symmetric, different test coupons for the
lead-ins and lead-outs are required.
User Manual 1173.9163.02 ─ 62
DUT
Concepts and features
Offset parameters and de-/embedding
218