5 CALIBRATION AND CALIBRATION KIT
18.104.22.168 Two-Port Error Model
For a two-port measurement, two signal flow graphs are considered. One of the graphs
describes the case where port 1 is the stimulus source, the other graph describes the case
where port 2 is the stimulus source.
The signal flow graphs of errors effect in a two-port system are represented in figure
Figure 5.2 Two-port error model
§S11a, S21a, S12a, S22a – true values of the DUT parameters;
22m – measured values of the DUT
For normalization the stimulus value is taken equal to 1. All the values used in the
model are complex.
The measurement result in a two-port system is affected by twelve systematic error