A new calibration method for mixer delay measurements that requires no calibration mixer

Making phase and group delay response measurements on mixers and frequency converters has traditionally been a difficult and complicated process, requiring either modulated-signals (and demodulation), two-tone signals (a special form of modulation) or a system with a reference or reconverting mixer and a calibration or "golden" mixer. This paper presents a method to measure the phase response of a mixer on a VNA calibrating the input and output phase response independently, computing the transfer response directly using a phase reference, and is traceable to national standards. This method, for the first time, eliminates the need for any other mixer, reference or calibration, in the test system.