Calibrating an Arbitrary Test Fixture for a Symmetric Device by Three Measurements

In this paper, a general solution of calibrating a microwave test fixture for a symmetric device is deduced from the cascading network relation, and it exposes the probability and condition of calibrating an arbitrary test fixture for a symmetric device by three measurements, which is less than the times of measurements in the thru-reflect-line (TRL) method. The scattering parameters of the test fixture and the embedded symmetric device can be determined by measurements of a thru, a line, and the symmetric device. Furthermore, the method is analyzed and verified by simulation and measurement. The analysis indicates that the presented method is suitable for determining the calibrated $S$-parameters of a symmetric device under test (DUT).