Periodical Measurement Error With Respect to the Length of Thru in TRL Technique

A Method for Accurately Characterizing Single Overmoded Circular TM01-TE11 Mode Converter

“…As TM01A and TE11B mode generators are asymmetric two-port devices (both mechanically and electrically, as indicated in Fig.4) and its S-parameters cannot be measured directly with VNA, we have to find a way to extract the TM01A and TE11B mode generators' respective Sparameter matrix firstly. The TRL calibration technique [11], [22]- [24] is a classical method for extracting asymmetric fixtures' S-parameters, such as transitions from coaxial port to microstrip, substrate-integrated waveguide (SIW) [25], and so on. In Fig.1, the two TE 11 mode generator fixtures' Sparameters are actually extracted through the TRL calibration process and saved in VNA's calibration file [26], but it is encrypted and cannot be accessed for de-embedding calculation.…”

“…The kernel TRL calibration solution for getting individual fixture's S-parameters is as follows [22]- [24].…”