This calculator calculates Z from shunt s21 and related calibration measurements.
The calculator does not do a lot of error checking, if you enter nonsense, it will probably produce nonsense.
Inputs are assumed wrt 50+j0 (Ω).
A shunt impedance Zc is used to find the equivalent source impedance of Port 1 for improved accuracy. Zc is measured using a s11 reflection measurement.
Port 2 input impedance is measured by s11 reflection as Zl.
s21c is an s21 measurement with Zc in shunt from Port 1 to Port 2.
s21u is an s21 measurement with Zu (the unknown) in shunt from Port 1 to Port 2.
© Copyright: Owen Duffy 1995, 2021. All rights reserved. Disclaimer.