A Single-Element CMOS-LRRM VNA Electronic Calibration Technique

This paper presents a single-element CMOS-based electronic calibration (E-Cal) technique for millimeter-wave VNA measurements. The structure employs a CMOS transmission line loaded with a shunt NMOS transistor at its center tap. By taking advantage of the structure symmetry, the standard LRRM calibration flow can be implemented with the transistor biased at different impedance states. The approach is justified using a 65nm CMOS test chip and the measurements of passive DUTs.