Concepts and features
R&S
®
ZNB/ZNBT
218
User Manual 1173.9163.02 ─ 62
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.
DUT
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.
Offset parameters and de-/embedding
