Novel method to measure the conversion-losses (C.L.) of microwave and mm-wave mixers

Classic methods to measure the mixer conversion-losses (C.L.) usually need an absolute RF and IF power-measurement at the mixer´s ports. However, absolute power-measurement cannot be achieved with a low uncertainty level for the higher frequencies and mm-waves because of non-available standards and source & load mismatch problems. A new method is proposed (for reciprocal mixers) based on relative-power measurement at IF-port when the RF-port is fed/measured by VNA. Therefore, the C.L. can be evaluated for the mm-wave mixers by using a suitable VNA and its relevant frequency-converters up to 325GHz. The setup is described and preliminary results are presented for a microwave-mixer and a mm-wave one.