S-Parameters De-embedding at Cryogenic Temperature using One Reflect Standard

De-embedding S-parameters measurements at cryogenic temperature with a few amount of cooling cycles is a challenge. This paper presents an extensive investigation of a commercial automatic fixture removal (AFR) applied to cryogenic measurements of both magnitude and phase performance. This method uses a single reflect standard measurement and is adequate for multiport measurements. The procedure is applied to the characterization of a surface mounted balun and can use Open or Short standards. The investigation of the accuracy at cold temperature shows a deviation of 0.07 dB in magnitude and 8° in phase between 0 and 8 GHz. The AFR correction is reproducible with an error of 0.02 dB in magnitude and 0.2° in phase between two calibrations. This typical error is within the range of the intrinsic deviation for repeated measurements with the experimental setup.