A Comparative Study of TOSL, TRL, and TRL* Network Analyzer Calibration Techniques, Using Microstrip Test Fixtures

For many packaged devices, both active and passive, the preferred test fixture approach is one of microstrip transmission line design. In order to achieve accurate, and reliable two port s-parameter measurements, an accurate calibration of the fixture up to the DUT reference plane is essential. Modern vector network analyzers allow several options when it comes to performing the necessary systematic error correction or calibration. This paper will present results based on verification of three different calibration techniques, by measurement of well defined microstrip impedance standards under TOSL (Thru, open, short, load), TRL (Thru, reflect, line), and TRL* (Hewlett Packard`s modified TRL for three-sampler RF test sets).